1
|
Santos M, Fidalgo-Pereira R, Torres O, Carvalho O, Henriques B, Özcan M, Souza JCM. The impact of inorganic fillers, organic content, and polymerization mode on the degree of conversion of monomers in resin-matrix cements for restorative dentistry: a scoping review. Clin Oral Investig 2024; 28:454. [PMID: 39066793 PMCID: PMC11283416 DOI: 10.1007/s00784-024-05829-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Accepted: 07/13/2024] [Indexed: 07/30/2024]
Abstract
PURPOSE The main aim of the present study was to carry out a scoping review on the differences in degree of conversion of monomers regarding several types resin cements, indirect restorative materials, and light-curing procedures used in dentistry. METHOD A bibliographic review was performed on PubMed using the following search items: "degree of conversion" OR "filler" AND "resin cement" OR "inorganic cement" AND "organic" OR "radiopacity" OR "refractive" OR "transmittance" OR "type" AND "resin composite." The search involved articles published in English language within the last thirteen years. A research question has been formulated following the PICO approach as follow: "How different is the degree of conversion of monomers comparing several types of resin-matrix cements?". RESULTS Within the 15 selected studies, 8 studies reported a high degree of conversion (DC) of the organic matrix ranging from 70 up to 90% while 7 studies showed lower DC values. Dual-cured resin-matrix cements revealed the highest mean values of DC, flexural strength, and hardness when compared with light- and self-polymerized ones. DC mean values of resin-matrix cements light-cured through a ceramic veneer with 0.4 mm thickness were higher (~ 83%) than those recorded for resin-matrix cements light-cured through a thicker ceramic layer of 1.5 mm (~ 77%). CONCLUSIONS The highest percentage of degree of conversion of monomers was reported for dual-cured resin-matrix cements and therefore both chemical and light-induced pathways promoted an enhanced polymerization of the material. Similar degree of conversion of the same resin-matrix cement were recorded when the prosthetic structure showed a low thickness. On thick prosthetic structures, translucent materials are required to allow the light transmission achieving the resin-matrix cement. CLINICAL RELEVANCE The chemical composition of resin-matrix cements and the light-curing mode can affect the polymerization of the organic matrix. Thus, physical properties of the materials can vary leading to early clinical failures at restorative interfaces. Thus, the analysis of the polymerization pathways of resin-matrix cements is significantly beneficial for the clinical performance of the restorative interfaces.
Collapse
Affiliation(s)
- Marcionilia Santos
- Oral Pathology and Rehabilitation Research Unit (UNIPRO), University Institute of Health Sciences (IUCS), CESPU, 4585-116, Gandra PRD, Portugal
| | - Rita Fidalgo-Pereira
- Center for Interdisciplinary Research in Health (CIIS), Faculty of Dental Medicine (FMD), Universidade Católica Portuguesa (UCP), 3504-505, Viseu, Portugal
| | - Orlanda Torres
- Oral Pathology and Rehabilitation Research Unit (UNIPRO), University Institute of Health Sciences (IUCS), CESPU, 4585-116, Gandra PRD, Portugal
| | - Oscar Carvalho
- Center for MicroElectroMechanical Systems (CMEMS-UMINHO), University of Minho, Campus Azurém, 4800-058, Guimarães, Portugal
- Associate Laboratory (LABBELS), University of Minho, 4710-057, Guimarães, Braga, Portugal
| | - Bruno Henriques
- Center for MicroElectroMechanical Systems (CMEMS-UMINHO), University of Minho, Campus Azurém, 4800-058, Guimarães, Portugal
- Associate Laboratory (LABBELS), University of Minho, 4710-057, Guimarães, Braga, Portugal
- Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina (UFSC), Campus Trindade, Florianópolis, SC, 88040-900, Brazil
| | - Mutlu Özcan
- Clinic for Masticatory Disorders and Dental Biomaterials, Center of Dental Medicine, University of Zurich, 8032, Zurich, Switzerland
| | - Júlio C M Souza
- Center for Interdisciplinary Research in Health (CIIS), Faculty of Dental Medicine (FMD), Universidade Católica Portuguesa (UCP), 3504-505, Viseu, Portugal.
- Center for MicroElectroMechanical Systems (CMEMS-UMINHO), University of Minho, Campus Azurém, 4800-058, Guimarães, Portugal.
- Associate Laboratory (LABBELS), University of Minho, 4710-057, Guimarães, Braga, Portugal.
| |
Collapse
|
2
|
Xu L, Zhang Y, Jin S, Luo S, Chen K, Fang S, Zhong L, Zhang J, He R. Novel lignin α-O-4 derived hydrogen donors in CQ-based photoinitiating systems for dental resins. Sci Rep 2024; 14:16719. [PMID: 39030243 PMCID: PMC11271577 DOI: 10.1038/s41598-024-67377-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Accepted: 07/10/2024] [Indexed: 07/21/2024] Open
Abstract
The purpose of this work is to explore the properties of the lignin-derived amine-free photoinitiating systems (PISs) during the curing process. Four novel hydrogen donors (HD1, HD2, HD3, and HD4) derived from lignin α-O-4 structural were designed and synthesized by simple methods, and their low C-H bond dissociation energies on methylene were determined by molecular orbitals theory. Four experimental groups using CQ (camphorquinone)/HD PIs formulated with Bis-GMA/TEGDMA (70 w%/30 w%) were compared to CQ/EDB (ethyl 4-dimethylamino benzoate) system. The photopolymerization profiles and double bond conversion rate was tracked by FTIR experiments; the color bleaching ability of the samples and color aging test assay were performed using color indexes measurements; The cytotoxicity of the samples was also compared to EDB related systems. All of the experimental groups with new HDs were compared to the control group with EDB by statistical analysis. Compared to CQ/EDB system, new lignin-derived hydrogen donors combined with CQ showed comparable or even better performances in polymerization initiation to form resin samples, under a blue dental LED in air. Excellent color bleaching property was observed with the new HDs. Aging tests and cytotoxicity examination of the resin were performed, indicating the new lignin compounds to be efficient hydrogen donors for amine-free CQ-based photo-initiating system. Novel lignin α-O-4 derived hydrogen donors are promising for further usage in light-curing materials.
Collapse
Affiliation(s)
- Lixia Xu
- Center of Stomatology, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, Zhejiang, China
- The 3rd People's Hospital of Deqing, Huzhou, Zhejiang, China
| | - Ying Zhang
- Center of Stomatology, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, Zhejiang, China
- School of Stomatology, Hangzhou Normal University, Hangzhou, Zhejiang, China
| | - Shuqi Jin
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, Hangzhou, Zhejiang, China
| | - Shuxin Luo
- Center of Stomatology, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, Zhejiang, China
- Zhejiang Provincial Hospital of Chinese Medicine, Hangzhou, Zhejiang, China
| | - Kailun Chen
- Center of Stomatology, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, Zhejiang, China
- School of Stomatology, Hangzhou Normal University, Hangzhou, Zhejiang, China
| | - Sheng Fang
- Center of Stomatology, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, Zhejiang, China
- School of Stomatology, Hangzhou Normal University, Hangzhou, Zhejiang, China
| | - Liangjun Zhong
- Center of Stomatology, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, Zhejiang, China
- School of Stomatology, Hangzhou Normal University, Hangzhou, Zhejiang, China
| | - Jian Zhang
- Center of Stomatology, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, Zhejiang, China
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, Hangzhou, Zhejiang, China
- School of Stomatology, Hangzhou Normal University, Hangzhou, Zhejiang, China
| | - Rui He
- Center of Stomatology, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, Zhejiang, China.
- School of Stomatology, Hangzhou Normal University, Hangzhou, Zhejiang, China.
| |
Collapse
|
3
|
Novta E, Pantelić D, Blažić L, Tóth E, Cvejić Ž, Grujić D, Savić-Šević S, Lainović T. Impact of optical fiber-based photo-activation on dental composite polymerization. J Dent 2024; 145:104998. [PMID: 38636650 DOI: 10.1016/j.jdent.2024.104998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 04/04/2024] [Accepted: 04/16/2024] [Indexed: 04/20/2024] Open
Abstract
OBJECTIVES The study aimed to introduce a novel two-step optical fiber-based photo-activation of dental resin-based composites (RBCs) for reducing polymerization shrinkage stress (PSS). METHODS Proposed protocol design - in the first step, two flexible plastic optical fibers connected to a dental light curing unit (LCU), were used as light guides inserted into the filling to initiate low-irradiance polymerization from within; in the second step, fibers were extracted and remaining voids were filled with RBC, followed by conventional high-irradiance curing to finalize polymerization. Three bulk-fill RBCs were tested (Beautifil-Bulk Restorative, Filtek Bulk-fill Posterior, Tetric PowerFill) using tooth cavity models. Three non-invasive examination techniques were employed: Digital Holographic Interferometry, Infrared Thermography, and Raman spectroscopy for monitoring model deformation, RBC temperature change, and degree of conversion (DC), respectively. A control group (for each examined RBC) underwent conventional photo-activation. RESULTS The experimental protocol significantly reduced model deformation by 15 - 35 %, accompanied by an 18 - 54 % reduction in RBC temperature change, emphasizing the impact of thermal shrinkage on PSS. Real-time measurements of deformation and temperature provided indirect insights into reaction dynamics and illuminated potential mechanisms underlying PSS reduction. After a 24-hour dark-storage period, DC outcomes comparable to conventional curing were observed, affirming the clinical applicability of the method. CONCLUSIONS Protocol involving the use of two 1.5 mm fibers in the first step (300 mW/cm2 x 10 s), followed by a second conventional curing step (1000 mW/cm2 x 10 s), is recommended to achieve the desired PSS reduction, while maintaining adequate DC and ensuring efficient clinical application. CLINICAL SIGNIFICANCE Obtained PSS reduction offers promise in potentially improving the performance of composite restorations. Additionally, leveraging the flexibility of optical fibers improves light guide approach for restorations on posterior teeth. Meanwhile, implementation in clinical practice is easily achievable by coupling the fibers with commercial dental LCUs using the provided plastic adapter.
Collapse
Affiliation(s)
- Evgenije Novta
- University of Novi Sad, Faculty of Medicine, School of Dental Medicine, Hajduk Veljkova 12, Novi Sad, Serbia.
| | - Dejan Pantelić
- University of Belgrade, Institute of Physics, Pregrevica 118, Belgrade, Serbia
| | - Larisa Blažić
- University of Novi Sad, Faculty of Medicine, School of Dental Medicine, Hajduk Veljkova 12, Novi Sad, Serbia; Dental clinic of Vojvodina, Hajduk Veljkova 12, Novi Sad, Serbia
| | - Elvira Tóth
- University of Novi Sad, Faculty of Sciences, Department of Physics, Trg Dositeja Obradovića 3, Novi Sad, Serbia
| | - Željka Cvejić
- University of Novi Sad, Faculty of Sciences, Department of Physics, Trg Dositeja Obradovića 3, Novi Sad, Serbia
| | - Dušan Grujić
- University of Belgrade, Institute of Physics, Pregrevica 118, Belgrade, Serbia
| | | | - Tijana Lainović
- University of Novi Sad, Faculty of Medicine, School of Dental Medicine, Hajduk Veljkova 12, Novi Sad, Serbia
| |
Collapse
|
4
|
Li A, Wei X, Xie Y, Ren Y, Zhu X, Liu M, Liu S. Light exposure and its applications in human health. JOURNAL OF BIOPHOTONICS 2024; 17:e202400023. [PMID: 38576140 DOI: 10.1002/jbio.202400023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 03/13/2024] [Accepted: 03/25/2024] [Indexed: 04/06/2024]
Abstract
Light exposure has been proven to have a significant impact on human health. As a result, researchers are increasingly exploring its potential benefits and drawbacks. With advancements in understanding light and the manufacturing of light sources, modern health lighting has become widely utilized in daily life and plays a critical role in the prevention and treatment of various illnesses. The use of light in healthcare is a global trend, with many countries actively promoting the development and application of relevant scientific research and medical technology. This field has gained worldwide attention and support from scientists and doctors alike. In this review, we examine the application of lighting in human health and recent breakthroughs in light exposure related to pathology, therapeutic strategies, molecular changes, and more. Finally, we also discuss potential future developments and areas of application.
Collapse
Affiliation(s)
- Angze Li
- School of Information Science and Technology, Fudan University, Shanghai, China
- Zhongshan Fudan Joint Innovation Center, Zhongshan, Guangdong Province, China
| | - Xiaoling Wei
- Department of Endodontics, Shanghai Stomatological Hospital, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Craniomaxillofacial Development and Diseases, Shanghai Stomatological Hospital, Fudan University, Shanghai, China
| | - Yajia Xie
- Department of Endodontics, Shanghai Stomatological Hospital, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Craniomaxillofacial Development and Diseases, Shanghai Stomatological Hospital, Fudan University, Shanghai, China
| | - Yi Ren
- School of Information Science and Technology, Fudan University, Shanghai, China
- Zhongshan Fudan Joint Innovation Center, Zhongshan, Guangdong Province, China
| | - Xi Zhu
- Zhongshan Fudan Joint Innovation Center, Zhongshan, Guangdong Province, China
| | - Muqing Liu
- School of Information Science and Technology, Fudan University, Shanghai, China
- Zhongshan Fudan Joint Innovation Center, Zhongshan, Guangdong Province, China
| | - Shangfeng Liu
- Shanghai Key Laboratory of Craniomaxillofacial Development and Diseases, Shanghai Stomatological Hospital, Fudan University, Shanghai, China
| |
Collapse
|
5
|
Pacheco RR, Garcia-Flores AF, Lesseux GG, Lancelotti A, Rettori C, Urbano RR, Giannini M, Rueggeberg FA. Comparison of Blue and Infrared Light Transmission Through Dental Tissues and Restorative Materials. Oper Dent 2024; 49:300-310. [PMID: 38632862 DOI: 10.2341/23-056-l] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/18/2023] [Indexed: 04/19/2024]
Abstract
OBJECTIVES The depth of cure using blue-light photocuring units (BL) is limited by tooth structure and qualities of the restorative material through which the activating wavelength must pass. Recent developments incorporate an infrared (IR) activated upconversion (UC) fluorescence of a lining agent filled with nanocrystals of NaYF4 and doped with YB+3 and Tm+3 that emit both blue and violet light locally at the interface of the liner and restorative resin. The purpose of this study was to evaluate the BL and 975 nm infrared (IR) light power transmission through dental tissues and restorative materials. METHODS AND MATERIALS Power transmissions of the IR laser (975 nm) and a monowave blue-only light-curing unit (Bluephase 16i) through dental tissues (enamel, dentin, and enamel/dentin junction, or DEJ), eight (8) various dental resin composites, and eight (8) dental ceramics, each at four thicknesses (1, 2, 3 and 4 mm) were evaluated (n=5) using a thermopile sensor (PM10, Coherent Inc) connected to a laser power meter (Fieldmate, Coherent Inc). Power transmission values of each light source and restorative material were subjected to analysis of variance and Tukey test at a pre-set alpha of 0.05. RESULTS A linear correlation (r=0.9884) between the supplied current and emitted IR power of the laser diode was found, showing no statistical power reduction with increased distances (collimated beam). For tooth tissues, the highest power transmissions for both light sources were observed using 1.0 mm enamel while the lowest values were found for 2.0 mm dentin and an association of 2.0 mm DEJ and 1.0 mm dentin. The only group where IR demonstrated significantly higher transmission when compared to BL was 1.0 mm enamel. For all resin composites and dental ceramics, increased thickness resulted in a reduction of IR power transmission (except for EverX Posterior fiber-reinforced composite and e.max HT ceramic). IR resulted in higher transmission through all resin composites, except for Tetric EvoCeram White. The highest BL transmission was observed for SDR Flow, at all thicknesses. Higher IR/BL ratios were observed for EverX Posterior, Herculite Ultra, and Lava Ultimate, while the lowest ratio was observed for Tetric EvoCeram White. Reduced translucency shades within the same material resulted in lower power ratio values, especially for BL transmission. Higher IR/BL ratios were observed for e.Max LT, VitaVM7 Base Dentin, and e.max CAD HT, while the lowest values were found for VitaVM7 Enamel and Paradigm C. CONCLUSION IR power transmission through enamel was higher when compared to blue light, while no difference was observed for dentin. The power transmission of IR was higher than BL for resin composites, except for a high value and low chroma shade. Fiber-reinforced resin composite demonstrated the highest IR/BL power transmission ratio. A greater IR/BL ratio was observed for lower translucency ceramics when compared to high translucency.
Collapse
Affiliation(s)
- R R Pacheco
- *Rafael Rocha Pacheco, DDS, MSc, PhD, Department of Restorative Sciences, The Dental College of Georgia at Augusta University, Augusta, GA, USA
| | - A F Garcia-Flores
- Ali Francisco Garcia-Flores, MSc, PhD, State University of Campinas, São Paulo, Brazil
| | - G G Lesseux
- Guilherme Gorgen Lesseux, MSc, PhD, State University of Campinas, São Paulo, Brazil
| | - Acra Lancelotti
- Ailla Carla Rocha Acosta Lancelotti, DDS, MSc, PhD, State University of Campinas, São Paulo, Brazil
| | - C Rettori
- Carlos Rettori, MSc, PhD, State University of Campinas, São Paulo, Brazil
| | - R R Urbano
- Ricardo Rodrigues Urbano, MSc, PhD, State University of Campinas, São Paulo, Brazil
| | - M Giannini
- Marcelo Giannini, DDS, MSc, PhD, State University of Campinas, São Paulo, Brazil
| | - F A Rueggeberg
- Frederick Allen Rueggeberg, DDS, MS, Department of Restorative Sciences, The Dental College of Georgia at Augusta University, Augusta, GA, USA
| |
Collapse
|
6
|
Wang P, Ge M, Luo X, Zhai Y, Meckbach N, Strehmel V, Li S, Chen Z, Strehmel B. Confinement of Sustainable Carbon Dots Results in Long Afterglow Emitters and Photocatalyst for Radical Photopolymerization. Angew Chem Int Ed Engl 2024:e202402915. [PMID: 38569128 DOI: 10.1002/anie.202402915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 03/19/2024] [Accepted: 03/20/2024] [Indexed: 04/05/2024]
Abstract
Sustainable carbon dots based on cellulose, particularly carboxymethyl cellulose carbon dots (CMCCDs), were confined in an inorganic network resulting in CMCCDs@SiO2. This resulted in a material exhibiting long afterglow covering a time frame of several seconds also under air. Temperature-dependent emission spectra gave information on thermally activated delayed fluorescence (TADF) and room temperature phosphorescence (RTP) while photocurrent experiments provided a deeper understanding of charge availability in the dark period, and therefore, its availability on the photocatalyst surface. The photo-ATRP initiator, ethyl α-bromophenylacetate (EBPA), quenched the emission from the millisecond to the nanosecond time frame indicating participation of the triplet state in photoinduced electron transfer (PET). Both free radical and controlled radical polymerization based on photo-ATRP protocol worked successfully. Metal-free photo-ATRP resulted in chain extendable macroinitiators based on a reductive mechanism with either MMA or in combination with styrene. Addition of 9 ppm Cu2+ resulted in Mw/Mn of 1.4 while an increase to 72 ppm improved uniformity of the polymers; that is Mw/Mn=1.03. Complementary experiments with kerria laca carbon dots confined materials, namely KCDs@SiO2, provided similar results. Deposition of Cu2+ (9 ppm) on the photocatalyst surface explains better uniformity of the polymers formed in the ATRP protocol.
Collapse
Affiliation(s)
- Ping Wang
- Northeast Forestry University, Key Laboratory of Bio-based Material Science and Technology of Ministry of Education, Hexing Road 26, 150040, Harbin, China
- Niederrhein University of Applied Sciences, Department of Chemistry, Institute for Coatings and Surface Chemistry, Adlerstr. 1, D-47798, Krefeld, Germany
| | - Min Ge
- Northeast Forestry University, Key Laboratory of Bio-based Material Science and Technology of Ministry of Education, Hexing Road 26, 150040, Harbin, China
| | - Xiongfei Luo
- Northeast Forestry University, Key Laboratory of Bio-based Material Science and Technology of Ministry of Education, Hexing Road 26, 150040, Harbin, China
- Niederrhein University of Applied Sciences, Department of Chemistry, Institute for Coatings and Surface Chemistry, Adlerstr. 1, D-47798, Krefeld, Germany
- Northeast Forestry University, College of Chemistry, Chemical Engineering and Resource Utilization, Hexing Road 26, 150040, Harbin, China
| | - Yingxiang Zhai
- Northeast Forestry University, Key Laboratory of Bio-based Material Science and Technology of Ministry of Education, Hexing Road 26, 150040, Harbin, China
| | - Nicolai Meckbach
- Niederrhein University of Applied Sciences, Department of Chemistry, Institute for Coatings and Surface Chemistry, Adlerstr. 1, D-47798, Krefeld, Germany
| | - Veronika Strehmel
- Niederrhein University of Applied Sciences, Department of Chemistry, Institute for Coatings and Surface Chemistry, Adlerstr. 1, D-47798, Krefeld, Germany
| | - Shujun Li
- Northeast Forestry University, Key Laboratory of Bio-based Material Science and Technology of Ministry of Education, Hexing Road 26, 150040, Harbin, China
| | - Zhijun Chen
- Northeast Forestry University, Key Laboratory of Bio-based Material Science and Technology of Ministry of Education, Hexing Road 26, 150040, Harbin, China
- Heilongjiang International Joint Lab of Advanced Biomass Materials, Northeast Forestry University, Hexing Road 26, 150040, Harbin, China
| | - Bernd Strehmel
- Niederrhein University of Applied Sciences, Department of Chemistry, Institute for Coatings and Surface Chemistry, Adlerstr. 1, D-47798, Krefeld, Germany
| |
Collapse
|
7
|
Braga SSL, Price RB, Juckes SM, Sullivan B, Soares CJ. Effect of the violet light from polywave light-polymerizing units on two resin cements that use different photoinitiators. J Prosthet Dent 2024; 131:744-751. [PMID: 35369979 DOI: 10.1016/j.prosdent.2022.02.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 02/19/2022] [Accepted: 02/21/2022] [Indexed: 11/18/2022]
Abstract
STATEMENT OF PROBLEM Some light-emitting diode polymerization lights have been promoted as multiple peak or polywave lights that use multiple light-emitting diodes to produce both violet and blue light. However, whether the addition of violet light is required to light-activate resin cements that use bis(4-methoxybenzoyl)diethylgermane (Ivocerin) as the photoinitiator is unclear. PURPOSE This in vitro study evaluated the effect of violet, blue, or a combination of violet and blue light through ceramic on the degree of conversion of 2 resin cements that use either camphorquinone or Ivocerin as the photoinitiator. MATERIAL AND METHODS A Bluephase Style polywave light-emitting diode polymerizing unit delivering 6.4 J/cm2 of violet and blue light was used. This comprised 1.4 J/cm2 of violet (385 to 420 nm) and 5.0 J/cm2 of blue light (420 to 515 nm). The light-emitting diode emitters in a second modified Bluephase Style were connected directly to a power supply so that either just violet (1.4 J/cm2) or just blue (5.0 J/cm2) light was emitted. RelyX Veneer and Variolink Esthetic LC resin cements were either directly light-activated or through 0.5 or 1.5 mm of lithium disilicate ceramic (IPS e.max CAD). The degree of conversion was monitored by using Fourier-transform infrared spectroscopy. Data were subject to a 3-way analysis of variance followed by the Tukey honest significant difference multiple comparison tests (α=.05). RESULTS All factors had a significant effect (P<.001). Increasing the ceramic thickness decreased the degree of conversion only for RelyX Veneer cement (P<.001). The effect of the thickness of ceramic was most noticeable when just violet light was delivered to RelyX Veneer. A significant reduction (P<.001) was found in the degree of conversion of RelyX Veneer when just violet light was delivered. Variolink Esthetic LC had significantly higher degree of conversion values than RelyX Veneer, irrespective of the light type used (P<.001). CONCLUSIONS A multiple-peak light is not required to photopolymerize a resin cement that uses either camphorquinone or Ivocerin as its photoinitiator. Adding the violet light produced no significant increase in the degree of conversion of the Variolink Esthetic LC cement.
Collapse
Affiliation(s)
- Stella Sueli Lourenço Braga
- Doctoral student, Department of Operative Dentistry and Dental Materials, Dental School, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil
| | - Richard Bengt Price
- Professor, Department of Dental Clinical Sciences, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Stefan Mikhail Juckes
- Research Assistant, Department of Dental Clinical Sciences, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Braden Sullivan
- Research Assistant, Department of Dental Clinical Sciences, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Carlos José Soares
- Professor and Chair, Department of Operative Dentistry and Dental Materials, Dental School, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil.
| |
Collapse
|
8
|
Nabil M, Hasan MM, Shebl EAE. Effect of antioxidant on tooth sensitivity after bleaching. J ESTHET RESTOR DENT 2024; 36:429-436. [PMID: 38130089 DOI: 10.1111/jerd.13190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 12/10/2023] [Accepted: 12/11/2023] [Indexed: 12/23/2023]
Abstract
OBJECTIVES This study aimed to investigate the effect of antioxidant (sodium ascorbate) on tooth sensitivity after two in-office bleaching techniques (light-activated and chemical bleaching). MATERIALS AND METHODS Ten patients aged 18-25 were bleached in four groups according to bleaching materials and/or antioxidant used. Group A: Maxillary right quadrant received light-activated bleaching with antioxidant. Group B: Maxillary left quadrant received light-activated bleaching without antioxidant. Group C: Mandibular right quadrant received chemical bleaching without antioxidant. Group D: Mandibular left quadrant received chemical bleaching with antioxidant. The tooth sensitivity was recorded using Numerical Rating Scale (NRS) and Schiff Scale (SS) immediately after treatment, 1 day, 1 week, 2 weeks, and 1 month follow-up periods. RESULTS Group B exhibited higher sensitivity values than Group A. This difference was statistically significant on the first day after treatment (p = 0.027* in NRS and p = 0.046* in SS). Furthermore, antioxidant incorporation in Group D led to a reduction in teeth sensitivity values compared to Group C. This disparity was highly significant on the first day after treatment (p = 0.001* in NRS and p < 0.001** in SS). CONCLUSIONS The antioxidant (10% sodium ascorbate) reduces the intensity of tooth sensitivity at the different follow-up periods, especially after 1 day from bleaching. CLINICAL SIGNIFICANCE Using 10% sodium ascorbate after bleaching is advisable to reduce post-operative tooth sensitivity.
Collapse
Affiliation(s)
- Mohamed Nabil
- Department of Restorative Dentistry, Faculty of Dentistry, Sinai University, Ismailia, Egypt
| | - Mostafa Mohamed Hasan
- Department of Restorative Dentistry, Faculty of Dentistry, Tanta University, Tanta, Egypt
| | - Eman Abd Elghany Shebl
- Department of Restorative Dentistry, Faculty of Dentistry, Tanta University, Tanta, Egypt
| |
Collapse
|
9
|
Comisi JC, Maucoski C, Beller JP, Dennis KS, Price RB. A Blinded Comparative Study of Four Commercially Available LEDs and a Laser Light Curing Device. Eur J Dent 2023; 17:1065-1074. [PMID: 36574780 PMCID: PMC10756821 DOI: 10.1055/s-0042-1757908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
OBJECTIVE This study determined the effectiveness of five light-curing units (LCUs; four light-emitting diode [LED] and one laser) used on different settings to photo-activate four conventional resin-based composites (RBCs). MATERIALS AND METHODS A total of 108 RBC specimens were photo-activated in a white Delrin mold representing a mesial-occlusal-distal (MOD) class II restoration in a molar tooth. The proximal boxes were 5 mm deep, and the mesial-distal length was 12 mm. Immediately after photo-curing, the RBC specimens were immersed in a solvent to remove the uncured materials, after which they were photographed and deidentified. A Research Electronic Data Capture survey was created using these images and sent to respondents who blindly assessed the ability of the various LCUs to photo-cure the MOD restorations. RESULTS There were significant differences in how the five curing lights had cured RBCs. One-way analysis of variance (ANOVA), pairwise t-test, Welch's one-way ANOVA, and Kruskal-Wallis rank test in the blinded survey data showed significant differences between the LED curing lights used for two 10-second cures and the laser curing light used for 1 second, and LED lights at lower settings. CONCLUSION There was a significant difference in how the curing lights could photo-cure the RBCs used in this study. The laser curing light used for 1 second produced the worst results in all four RBCs.
Collapse
Affiliation(s)
- John C. Comisi
- Department of Oral Rehabilitation, James B. Edwards College of Dental Medicine, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Cristiane Maucoski
- Department of Dental Clinical Sciences, Faculty of Dentistry, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Jonathan P. Beller
- Department of Oral Rehabilitation, James B. Edwards College of Dental Medicine, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Kyle S. Dennis
- Department of Oral Rehabilitation, James B. Edwards College of Dental Medicine, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Richard B. Price
- Department of Dental Clinical Sciences, Faculty of Dentistry, Dalhousie University, Halifax, Nova Scotia, Canada
| |
Collapse
|
10
|
Michailidou S, Dionysopoulos D, Papadopoulos C, Naka O, Andriotis E, Fatouros D, Tolidis K. Effect of a Diode Laser (445 nm) on Polymerization Efficiency of a Preheated Resin Composite Used for Luting of Indirect Composite Restorations. Oper Dent 2023; 48:513-523. [PMID: 37503655 DOI: 10.2341/22-065-l] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/20/2023] [Indexed: 07/29/2023]
Abstract
PURPOSE The aim of this study was to evaluate the polymerization efficiency of a preheated resin composite used as a luting agent for indirect restorations light-cured by a blue diode laser (445 nm). METHODS Bronze molds were used to prepare cylindrical specimens of a laboratory composite (Ceramage) with dimensions 2, 3, and 4 mm in height and 8 mm in diameter. The molds had additional height of 120 μm for the placement of the preheated resin composite. A nanohybrid resin composite (Enamel Plus HRi) was preheated at 55°C to use as a luting agent. Photopolymerization was followed for 20 seconds using three light sources: a diode laser emitting at 445 nm (SiroLaser Blue) and two light-emitting diode (LED) units (Bluephase Style and Valo). Degree of conversion (DC) of the preheated resin composite was evaluated using Fourier transform infrared spectroscopy. RESULTS The results indicated that the main effects of the analysis were significant for both material thickness (p<0.001) and polymerization method (p<0.001). The preheated resin composite was not polymerized under 4-mm-thick specimens, independent of the light-curing unit. For 2-mm material thickness, there was no difference among the three light-curing units (p=0.383), while 3-mm Bluephase Style presented very low DC. CONCLUSIONS Diode laser (445 nm) achieved better polymerization efficiency at the same fluence compared to the LED unit at 3-mm depth, implying a better mechanical behavior and potential improved adhesion of the luting material to dentin.
Collapse
Affiliation(s)
- S Michailidou
- Stefania Michailidou, DDS, Department of Operative Dentistry, Faculty of Dentistry, School of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - D Dionysopoulos
- *Dimitrios Dionysopoulos, PhD, MSc, DDS, Department of Operative Dentistry, Faculty of Dentistry, School of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - C Papadopoulos
- Constantinos Papadopoulos, PhD, MSc, PhD, Department of Operative Dentistry, Faculty of Dentistry, School of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - O Naka
- Olga Naka, PhD, MClinDent, DDS, Department of Prosthodontics, Faculty of Dentistry, School of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - E Andriotis
- Eleftherios Andriotis, PhD, MSc, MEng, Department of Pharmaceutical Technology, Faculty of Pharmacy, School of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - D Fatouros
- Dimitrios Fatouros, PhD, MSc, BSc, Department of Pharmaceutical Technology, Faculty of Pharmacy, School of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - K Tolidis
- Kosmas Tolidis, PhD, MSc, DDS, Department of Operative Dentistry, Faculty of Dentistry, School of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| |
Collapse
|
11
|
Lima RBW, Melo AMDS, Dias JDN, Barbosa LMM, Santos JVDN, Souza GMD, Andrade AKM, Assunção IVD, Borges BCD. Are polywave light-emitting diodes more effective than monowave ones in the photoactivation of resin-based materials containing alternative photoinitiators? A systematic review. J Mech Behav Biomed Mater 2023; 143:105905. [PMID: 37201225 DOI: 10.1016/j.jmbbm.2023.105905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 05/05/2023] [Accepted: 05/08/2023] [Indexed: 05/20/2023]
Abstract
OBJECTIVE This systematic review aimed to analyze if using polywave light-emitting diodes (LED) to photoactivate resin-based materials (resin composites, adhesive systems, and resin cements) containing alternative photoinitiators provide better physicochemical properties than monowave ones. MATERIAL AND METHODS Inclusion criteria were in vitro studies that evaluated the degree of conversion, microhardness and flexural strength in resin-based materials containing alternative photoinitiators and light-activated with mono and polywave LEDs. Exclusion criteria were studies that evaluated the physicochemical properties of composites through any material interposed between the LED and the resin composite and studies that exclusively compared different modes and/or light activation times. Selection of studies, data extraction, and risk-of-bias analysis was performed. Data from selected studies were qualitatively analyzed. A systematic search was performed in June 2021 using PubMed/Medline, Embase, Scopus, and ISI Web of Science databases and grey literature without language restriction. RESULTS A total of 18 studies were included in the qualitative analysis. Nine studies used diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide (TPO) as an alternative photoinitiator for resin composite. Polywave LED improved the degree of conversion of resin composite compared to monowave in 9 of the included studies. Polywave LED improved the microhardness of resin composite compared to monowave in 7 of the included studies. Polywave LED improved the degree of conversion for 11 studies and microhardness of resin composite compared to monowave for 7 included studies. No differences in the flexural strength medium between poly and monowave LEDs were observed. The evidence was graded as low quality due to the high risk of bias for 11 studies. CONCLUSION The existing studies, with their limitations, revealed that the polywave light-emitting diode maximizes activation, resulting in a higher degree of double-bond conversion and microhardness of resin composites containing alternative photoinitiators. However, the flexural strength of these materials is not influenced by the type of light activation device.
Collapse
|
12
|
Maucoski C, Price RB, Arrais CAG. Temperature changes and hardness of resin-based composites light-cured with laser diode or light-emitting diode curing lights. Odontology 2023; 111:387-400. [PMID: 36184680 DOI: 10.1007/s10266-022-00745-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 09/13/2022] [Indexed: 11/25/2022]
Abstract
The temperature and Vickers Hardness (VH) at the top and bottom surfaces of three resin-based composites (RBCs) were measured when light-cured using five light-curing units (LCUs). The spectrum, power, and energy delivered to the top of the RBCs and transmitted through the RBCs were measured. Starting at 32℃, the temperature rise produced by the Monet Laser (ML-1 s and 3 s), Valo Grand (VG-3 s and 10 s), DeepCure (DC-10 s), PowerCure, (PC-3 s and 10 s) and PinkWave (PW-10 s) were measured at the bottom of specimens 2 mm deep × 6 mm wide made of Filtek Universal A2, Tetric Evoceram A2 and an experimental RBC codenamed Transcend UB. The VH values measured at the top and bottom of these RBCs were analyzed using ANOVA and Scheffe's post hoc test (p < 0.05) to determine the effects of the LCUs on the RBCs. The transmitted power from the ML was reduced by 77.4% through 2 mm of Filtek Universal, whereas light from PW decreased by only 36.8% through Transcend. The highest temperature increases from the LCU combined with the exothermic reaction occurred for Transcend, and overall, no significant differences were detected between Filtek Universal and Tetric Evoceram (p = 0.9756). Transcend achieved the highest VH values at the top and bottom surfaces. The PinkWave used for 10 s produced the largest temperature increase (20.2℃) in Transcend. The Monet used for 1 s produced the smallest increase (7.8℃) and the lowest bottom:top VH ratios.
Collapse
Affiliation(s)
- Cristiane Maucoski
- Department of Dental Clinical Sciences, Dalhousie University, Halifax, NS, B3H 4R2, Canada.
- Department of Restorative Dentistry, The State University of Ponta Grossa, 4748 General Carlos Cavalcanti Av., Ponta Grossa, Parana, 84051-130, Brazil.
| | - Richard Bengt Price
- Department of Dental Clinical Sciences, Dalhousie University, Halifax, NS, B3H 4R2, Canada
| | - Cesar Augusto Galvão Arrais
- Department of Restorative Dentistry, The State University of Ponta Grossa, 4748 General Carlos Cavalcanti Av., Ponta Grossa, Parana, 84051-130, Brazil
| |
Collapse
|
13
|
Lempel E, Szebeni D, Őri Z, Kiss T, Szalma J, Lovász BV, Kunsági-Máté S, Böddi K. The effect of high-irradiance rapid polymerization on degree of conversion, monomer elution, polymerization shrinkage and porosity of bulk-fill resin composites. Dent Mater 2023; 39:442-453. [PMID: 36918332 DOI: 10.1016/j.dental.2023.03.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 02/17/2023] [Accepted: 03/03/2023] [Indexed: 03/13/2023]
Abstract
OBJECTIVE The purpose was to compare the degree of conversion (DC), monomer elution (ME), polymerization shrinkage (PS) and porosity of two addition-fragmentation chain transfer (AFCT) modified resin-based composites (RBC) light-cured with rapid- (RP), turbo- (TP) or conventional polymerization (CP) settings. METHODS Cylindrical samples (6-mm wide, 4-mm thick) were prepared from Tetric PowerFill (TPF) and Filtek One Bulk (FOB). Four groups were established according to the polymerization settings: 3s-RP, 5s-TP, 10s-CP and 20s-CP. Samples in 1 mm thickness with 20s-CP settings served as controls. The DC at the top and bottom surfaces was measured with micro-Raman spectroscopy. ME was detected with high-performance liquid chromatography. PS and porosity were analyzed by micro-computed tomography. ANOVA and Tukey's post-hoc test, multivariate analysis and partial eta-squared statistics were used to analyze the data (p < 0.05). RESULTS FOB showed higher DC values (61.5-77.5 %) at the top compared to TPF (43.5-67.8 %). At the bottom TPF samples achieved higher DCs (39.9-58.5 %) than FOB (18.21-66.18 %). Extending the curing time increased DC (except the top of FOB) and decreased ME. BisGMA release was the highest among the detected monomers from both RBCs. The amount was three-fold more from TPF. The factor Material and Exposure significantly influenced DC and ME. PS (1.8-2.5 %) did not differ among the groups and RBCs except for the lowest value of TPF cured with the 3s_RP setting (p = 0.03). FOB showed 4.5-fold lower porosity (p < 0.001). Significantly higher pore volume was detected after polymerization in 3s_RP (p < 0.001). SIGNIFICANCE High-irradiance rapid 3-s curing of AFCT modified RBCs resulted in inferior results for some important material properties. A longer exposure time is recommended in a clinical situation.
Collapse
Affiliation(s)
- Edina Lempel
- Department of Restorative Dentistry and Periodontology, University of Pécs Medical School, Tüzér Street 1, Pécs 7623, Hungary.
| | - Donát Szebeni
- Department of Restorative Dentistry and Periodontology, University of Pécs Medical School, Tüzér Street 1, Pécs 7623, Hungary
| | - Zsuzsanna Őri
- János Szentágothai Research Center, Ifjúság Street 12, Pécs 7624, Hungary; Department of General and Physical Chemistry, University of Pécs, Ifjúság Street 6, Pécs 7624, Hungary
| | - Tamás Kiss
- János Szentágothai Research Center, Ifjúság Street 12, Pécs 7624, Hungary
| | - József Szalma
- Department of Oral and Maxillofacial Surgery, University of Pécs Medical School, Tüzér Street 1, Pécs 7623, Hungary
| | - Bálint Viktor Lovász
- Department of Oral and Maxillofacial Surgery, University of Pécs Medical School, Tüzér Street 1, Pécs 7623, Hungary
| | - Sándor Kunsági-Máté
- János Szentágothai Research Center, Ifjúság Street 12, Pécs 7624, Hungary; Department of Organic and Medicinal Chemistry, University of Pécs, Faculty of Pharmacy, Honvéd Street 1, Pécs 7624, Hungary
| | - Katalin Böddi
- Department of Biochemistry and Medical Chemistry, University of Pécs Medical School, Szigeti Street 12, Pécs 7624, Hungary
| |
Collapse
|
14
|
Luo S, Jin S, Xu L, Liao Y, He R, Zhang J, Zhong L. Lignin-derived new hydrogen donors for photoinitiating systems in dental materials. J Dent 2023; 132:104477. [PMID: 36914066 DOI: 10.1016/j.jdent.2023.104477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 03/01/2023] [Accepted: 03/04/2023] [Indexed: 03/14/2023] Open
Abstract
OBJECTIVES The aim of this study is to develop amine free photo-initiating system (PIs) for the photopolymerization of dental methacrylate resins, using seven new hydrogen donors HDA-HDG derived from β-O-4 lignin model. METHODS Seven experimental CQ/HD PIs were formulated with Bis-GMA/TEGDMA (70 w%/30 w%). CQ/EDB system was chosen as the comparison group. FTIR-ATR was used to monitor the polymerization kinetics and double bond conversion. Bleaching property and color stability were evaluated using a spectrophotometer. Molecular orbitals calculations were used to demonstrate C-H bond dissociation energies of the novel HDs. Depth of cure of the HD based systems were compared to the EDB based one. Cytotoxicity was also studied by CCK8 assay using tissue of mouse fibroblasts (L929 cells). RESULTS Compared to CQ/EDB system, the new CQ/HD systems show comparable or better photopolymerization performances (1 mm-thick samples). Comparable or even better bleaching properties were also obtained with the new amine-free systems. Comparing to EDB, all HDs exhibited significantly lower C-H bond dissociation energies by molecular orbitals calculations. Groups with new HD showed higher depth of cure. OD and RGR values were similar to that of the CQ/EDB group, ensuring the feasibility of the new HDs in dental materials. CLINICAL SIGNIFICANCE The new CQ/HD PI systems could be potentially useful in dental materials, presenting improvements in restorations' esthetic and biocompatibility.
Collapse
Affiliation(s)
- Shuxin Luo
- College of Stomatology, Hangzhou Normal University, Hangzhou 310000, China
| | - Shuqi Jin
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of, Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, Hangzhou 311121, China
| | - Lixia Xu
- College of Stomatology, Hangzhou Normal University, Hangzhou 310000, China
| | - Yilei Liao
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of, Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, Hangzhou 311121, China
| | - Rui He
- College of Stomatology, Hangzhou Normal University, Hangzhou 310000, China,; Center of Stomatology, Affiliated Hospital of Hangzhou Normal University, 310000, Hangzhou, China
| | - Jian Zhang
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of, Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, Hangzhou 311121, China; Center of Stomatology, Affiliated Hospital of Hangzhou Normal University, 310000, Hangzhou, China.
| | - Liangjun Zhong
- College of Stomatology, Hangzhou Normal University, Hangzhou 310000, China,; Center of Stomatology, Affiliated Hospital of Hangzhou Normal University, 310000, Hangzhou, China.
| |
Collapse
|
15
|
López-Torres J, Hernández-Caba K, Cervantes-Ganoza L, Ladera-Castañeda M, Martínez-Campos R, Solís-Dante F, Briceño-Vergel G, Cayo-Rojas C. Microleakage of Class II Bulk-Fill Resin Composite Restorations Cured with Light-Emitting Diode versus Quartz Tungsten-Halogen Light: An In Vitro Study in Human Teeth. Biomedicines 2023; 11:biomedicines11020556. [PMID: 36831092 PMCID: PMC9953121 DOI: 10.3390/biomedicines11020556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 01/28/2023] [Accepted: 02/08/2023] [Indexed: 02/17/2023] Open
Abstract
Background: Resin composites undergo a certain degree of shrinkage when light-cured with different light sources available on the market, resulting in microleakage of dental restorations. The aim of the present study was to assess microleakage of class II restorations with bulk-fill resin composites cured with LED (light-emitting diode) and QTH (quartz tungsten-halogen light) units, both in cervical and occlusal areas of cavity preparations. Materials and Methods: In the present in vitro experimental study, a total of 30 human molar teeth were used, in which 60 class II cavities were prepared (mesial and distal) and restored with Filtek bulk fill resin composite. Restorations were equally distributed in 3 groups according to type of curing light: A, QTH (Litex 680A Dentamerica®); B, LED (Bluephase N® 3rd generation); and C, LED (Valo® 3rd generation). Each group was further subdivided into subgroups 1 and 2 according to IV-A or IV-B resin composite color. Restored teeth were subjected to 20,000 thermal cycles between 5° and 55 °C, then immersed in 1M silver nitrate solution for 24 h. Subsequently, the teeth were sectioned mesiodistally to obtain samples for observation under stereomicroscope in order to determine microleakage degree. Kruskal-Wallis H and Mann-Whitney U statistical tests were applied with a significance level of 5% (p < 0.05). Results: No statistically significant differences were found in the degree of microleakage of bulk-fill resin composites light-cured with LED and QTH units for both occlusal (p > 0.05) and cervical areas (p > 0.05). Additionally, no significant differences were found when comparing microleakage between occlusal and cervical areas (p > 0.05), regardless of lamp type. In addition, significant differences in microleakage degree were found between bulk-fill resins with IV-A and IV-B shades when they were light-cured with QTH at cervical level (p = 0.023). However, there were no significant differences when comparing these bulk-fill resin composite shades at occlusal level with LED (p > 0.05) and QTH (p > 0.05) units. Conclusions: Class II restorations with bulk-fill resin composite in IV-A and IV-B shades light-cured with third generation LED lamp and QTH showed no significant differences in microleakage when compared in both occlusal and cervical areas. On the other hand, significantly more microleakage was found at the cervical level when a darker shade of resin composite was used and light-cured with the QTH unit.
Collapse
Affiliation(s)
- Jenny López-Torres
- School of Stomatology, Universidad Privada San Juan Bautista, Lima 15067, Peru
| | - Karen Hernández-Caba
- Research Team “Salud Pública—Salud Integral”, Faculty of Dentistry and Postgraduate School, Universidad Nacional Federico Villarreal, Lima 15001, Peru
| | | | - Marysela Ladera-Castañeda
- Research Team “Salud Pública—Salud Integral”, Faculty of Dentistry and Postgraduate School, Universidad Nacional Federico Villarreal, Lima 15001, Peru
| | - Reynaldo Martínez-Campos
- Oral Rehabilitation Department, School of Stomatology, Universidad Científica del Sur, Lima 15067, Peru
| | | | | | - César Cayo-Rojas
- School of Stomatology, Universidad Privada San Juan Bautista, Lima 15067, Peru
- Correspondence:
| |
Collapse
|
16
|
Effect of the Combination of Restorative Material and the Etching Protocol in Enamel Microleakage in Class II Cavities after Thermocycling. BIOMED RESEARCH INTERNATIONAL 2023; 2023:1354738. [PMID: 36820225 PMCID: PMC9938782 DOI: 10.1155/2023/1354738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 01/31/2023] [Accepted: 02/01/2023] [Indexed: 02/12/2023]
Abstract
This study is aimed at evaluating the marginal microleakage of bulk-fill class II restorations after thermocycling. Thirty-two human third molars received class II cavities prepared on mesial and distal faces. The cavities were bonded according to the adhesive protocol (total or self-etching). The cavities were then restored with composite and divided into 8 groups based on the composite combination: layering technique with Filtek Z350XT (G1 and G5), first layer with Filtek Z350 XT Flowable Restorative and then Filtek Z350XT (G2 and G6), bulk-fill technique with Filtek One Bulk Fill (G3 and G7), and first layer with Filtek One Bulk Fill Flow and Filtek Z350 XT (G4 and G8). The restorations were then subjected to thermocycling (2000 cycles, 5°C and 55°C, dwell time of 30 s). After aging, the restored teeth were immersed in methylene blue for 48 hours. The restorations (n = 32) were sectioned in the middle (two sections). The microleakage results were analyzed by two-way ANOVA followed by Tukey's post hoc test (α = 0.05). The groups did not differ statistically from each other in terms of marginal microleakage (p = 0.295). It can be concluded that there is no difference in the percentage of microleakage between conventional and bulk-fill resins on both consistencies, as well as there is also no statistically significant difference when the adhesive system is used in a conventional or self-etching mode.
Collapse
|
17
|
PEEK for Oral Applications: Recent Advances in Mechanical and Adhesive Properties. Polymers (Basel) 2023; 15:polym15020386. [PMID: 36679266 PMCID: PMC9864167 DOI: 10.3390/polym15020386] [Citation(s) in RCA: 25] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 01/06/2023] [Accepted: 01/07/2023] [Indexed: 01/15/2023] Open
Abstract
Polyetheretherketone (PEEK) is a thermoplastic material widely used in engineering applications due to its good biomechanical properties and high temperature stability. Compared to traditional metal and ceramic dental materials, PEEK dental implants exhibit less stress shielding, thus better matching the mechanical properties of bone. As a promising medical material, PEEK can be used as implant abutments, removable and fixed prostheses, and maxillofacial prostheses. It can be blended with materials such as fibers and ceramics to improve its mechanical strength for better clinical dental applications. Compared to conventional pressed and CAD/CAM milling fabrication, 3D-printed PEEK exhibits excellent flexural and tensile strength and parameters such as printing temperature and speed can affect its mechanical properties. However, the bioinert nature of PEEK can make adhesive bonding difficult. The bond strength can be improved by roughening or introducing functional groups on the PEEK surface by sandblasting, acid etching, plasma treatment, laser treatment, and adhesive systems. This paper provides a comprehensive overview of the research progress on the mechanical properties of PEEK for dental applications in the context of specific applications, composites, and their preparation processes. In addition, the research on the adhesive properties of PEEK over the past few years is highlighted. Thus, this review aims to build a conceptual and practical toolkit for the study of the mechanical and adhesive properties of PEEK materials. More importantly, it provides a rationale and a general new basis for the application of PEEK in the dental field.
Collapse
|
18
|
Rossegger E, Li Y, Frommwald H, Schlögl S. Vat photopolymerization 3D printing with light-responsive thiol-norbornene photopolymers. MONATSHEFTE FUR CHEMIE 2022. [DOI: 10.1007/s00706-022-03016-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
19
|
Ilie N. Resin-Based Bulk-Fill Composites: Tried and Tested, New Trends, and Evaluation Compared to Human Dentin. MATERIALS (BASEL, SWITZERLAND) 2022; 15:8095. [PMID: 36431581 PMCID: PMC9694352 DOI: 10.3390/ma15228095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 11/10/2022] [Accepted: 11/14/2022] [Indexed: 06/16/2023]
Abstract
A more-and-more-accepted alternative to the time-consuming and technique-sensitive, classic, incremental-layering technique of resin-based composites (RBCs) is their placement in large increments. The so-called bulk-fill RBCs had to be modified for a higher polymerization depth and already have a 20-year history behind them. From the initial simple mechanisms of increasing the depth of cure by increasing their translucency, bulk-fill RBCs have evolved into complex materials with novel polymerization mechanisms and bioactive properties. However, since the materials are intended to replace the tooth structure, they must be comparable in mechanical behavior to the substance they replace. The study compares already established bulk-fill RBCs with newer, less-studied materials and establishes their relationship to dentin with regard to basic material properties such as hardness and indentation modulus. Instrumented indentation testing enables a direct comparison of tooth and material substrates and provides clinically relevant information. The results underline the strong dependence of the measured properties on the amount of filler in contrast to the small influence of the material classes into which they are classified. The main difference of RBCs compared to dentin is a comparable hardness but a much lower indentation modulus, emphasizing further development potential.
Collapse
Affiliation(s)
- Nicoleta Ilie
- Department of Conservative Dentistry and Periodontology, University Hospital, Ludwig Maximilian University of Munich, Goethestr. 70, 80336 Munich, Germany
| |
Collapse
|
20
|
Steffen T, Par M, Attin T, Tauböck TT. Effect of Fast High-Irradiance Photo-Polymerization of Resin Composites on the Dentin Bond Strength. MATERIALS (BASEL, SWITZERLAND) 2022; 15:7467. [PMID: 36363058 PMCID: PMC9655088 DOI: 10.3390/ma15217467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 10/20/2022] [Accepted: 10/21/2022] [Indexed: 06/16/2023]
Abstract
This study investigated the influence of conventional (10 s at 1160 mW/cm2) and fast high-irradiance (3 s at 2850 mW/cm2) light curing on the micro-tensile bond strength (μTBS) of bulk-fill resin composites bonded to human dentin. Sixty-four extracted human molars were ground to dentin and randomly assigned into eight groups (n = 8 per group). After application of a three-step adhesive system (Optibond FL), four different bulk-fill composites (two sculptable and two flowable composites) were placed. Of these, one sculptable (Tetric PowerFill) and one flowable (Tetric PowerFlow) composite were specifically developed for fast high-irradiance light curing. Each composite was polymerized with the conventional or the fast high-irradiance light-curing protocol. The specimens were cut into dentin-composite sticks, μTBS was determined and failure modes were analyzed. Statistical analysis was performed using t-test for independent observations and one-way ANOVA. A statistical difference between the curing protocols was only found for Tetric PowerFlow, where the conventional protocol (23.8 ± 4.2 MPa) led to significantly higher values than the fast high-irradiance light-curing protocol (18.7 ± 3.7 MPa). All other composite materials showed statistically similar values for both polymerization protocols. In conclusion, the use of fast high-irradiation light curing has no negative influence on the μTBS of the investigated high-viscosity bulk-fill composites. However, it may reduce the dentin bond strength of flowable bulk-fill composite.
Collapse
Affiliation(s)
- Tobias Steffen
- Clinic of Conservative and Preventive Dentistry, Center for Dental Medicine, University of Zurich, 8032 Zurich, Switzerland
| | - Matej Par
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Gunduliceva 5, 10000 Zagreb, Croatia
| | - Thomas Attin
- Clinic of Conservative and Preventive Dentistry, Center for Dental Medicine, University of Zurich, 8032 Zurich, Switzerland
| | - Tobias T. Tauböck
- Clinic of Conservative and Preventive Dentistry, Center for Dental Medicine, University of Zurich, 8032 Zurich, Switzerland
| |
Collapse
|
21
|
Francis N, Rajan RR, Kumar V, Varughese A, Karuveetil V, Sapna CM. Effect of irradiance from curing units on the microhardness of composite - a systematic review. Evid Based Dent 2022:10.1038/s41432-022-0824-z. [PMID: 36253517 DOI: 10.1038/s41432-022-0824-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 02/07/2022] [Indexed: 11/08/2022]
Abstract
Purpose The systematic review aims to evaluate the effect of light irradiance from light-curing units on microhardness of composite.Materials and methods The protocol was registered in PROSPERO following which primary search was carried out via MedLine, Scopus and Cochrane Library. A customised tool was used to assess the risk of bias. Among the 303 records retrieved from the databases, only ten articles qualified for qualitative synthesis after meeting all the requirements of the eligibility criteria. Covidence software was used to record the decisions. The studies published until 31 March 2021 were taken up for the review. The articles showed a low-to-moderate risk of bias.Results From a total of 303 articles, ten articles were reviewed for full text. Ten in vitro studies were included for qualitative analysis. There was heterogeneity in sample size, curing time and outcome measured. Therefore, meta-analysis was not performed. Out of ten studies, seven studies reported higher microhardness value for higher intensity than lower intensity of light.Conclusion Despite the fact that the findings of the evaluated studies are quite variable, significant scientific evidence revealed that high light intensity can enhance the hardness of resin composites.
Collapse
Affiliation(s)
- Neenu Francis
- Department of Conservative Dentistry and Endodontics, Amrita School of Dentistry, Amrita Vishwa Vidyapeetham, Kochi 682041, India.
| | - Rakesh R Rajan
- Department of Conservative Dentistry and Endodontics, Amrita School of Dentistry, Amrita Vishwa Vidyapeetham, Kochi 682041, India
| | - Vijay Kumar
- Department of Public Health Dentistry, Amrita School of Dentistry, Amrita Vishwa Vidyapeetham, Kochi 682041, India
| | - Anju Varughese
- Department of Conservative Dentistry and Endodontics, Amrita School of Dentistry, Amrita Vishwa Vidyapeetham, Kochi 682041, India
| | - Vineetha Karuveetil
- Department of Public Health Dentistry, Amrita School of Dentistry, Amrita Vishwa Vidyapeetham, Kochi 682041, India
| | - C M Sapna
- Department of Conservative Dentistry and Endodontics, Amrita School of Dentistry, Amrita Vishwa Vidyapeetham, Kochi 682041, India
| |
Collapse
|
22
|
Abstract
This article focuses on the current understanding and concerns over the blue-light hazard when using dental light-curing units. It also provides information and safety protocols to guide the practitioner in making important decisions regarding dental personnel's health and the quality of dental restorations.
Collapse
Affiliation(s)
- Dayane Oliveira
- Center for Dental Biomaterials, Department of Restorative Dental Sciences, University of Florida - College of Dentistry, 1395 Center Drive D9-6, Gainesville, FL 32610, USA
| | - Mateus Garcia Rocha
- Center for Dental Biomaterials, Department of Restorative Dental Sciences, University of Florida - College of Dentistry, 1395 Center Drive D9-6, Gainesville, FL 32610, USA.
| |
Collapse
|
23
|
Vermudt A, Kuga MC, Besegato JF, de Oliveira ECG, Leandrin TP, Só MVR, Moraes JCS, Pereira JR. Effect of Curing Modes on the Mechanical Properties of Commercial Dental Resin-Based Composites: Comparison between Different LEDs and Microwave Units. Polymers (Basel) 2022; 14:polym14194020. [PMID: 36235967 PMCID: PMC9571923 DOI: 10.3390/polym14194020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 09/09/2022] [Accepted: 09/11/2022] [Indexed: 11/16/2022] Open
Abstract
Resin-based composites (RBCs) have transformed restorative dentistry and its procedures. However, the characteristics of RBCs have been modified over the years to enhance the physical and chemical properties of the materials. This context raises the need for studies that evaluate whether the properties of the RBCs that are commercially available are clinically adequate with different curing modes. This study aimed to evaluate the mechanical behavior of commercial RBCs after undergoing different curing modes. Twenty-three RBCs of different classes were evaluated. For curing the specimens, a microwave (BMS45, Brastemp) (for 3 min at 450 W) and three LED units were used: an Emitter A Fit (Schuster (second generation)) (light-curing for 15 s with an irradiance of 1250 mW/cm2), VALO (Ultradent (third generation)) (light-curing for 15 s with an irradiance of 1100 mW/cm2), and Emitter Now Duo (Schuster (second generation)) (light-curing for 15 s with an irradiance of 1100 mW/cm2). A total of 670 RBC specimens of 8 mm in diameter and 1 mm in depth were obtained. Afterward, a biaxial flexure strength test was performed until the failure of the specimens, using a universal testing machine set at a speed of 0.5 mm/min. The same specimens were subjected to infrared spectroscopy for evaluating the degree of conversion. Tukey’s test was used for multiple comparisons at a significance level of 5%. The light-curing mode did not affect the flexure strength of the RBCs (p > 0.05), but the type and shade of RBCs did so (p < 0.05). In conclusion, the type of RBC directly interferes with the mechanical behavior of the material. However, the curing modes within the same RBC did not change the mechanical properties.
Collapse
Affiliation(s)
- Alef Vermudt
- Postgraduate Program in Health Sciences, University of Southern Santa Catarina–Unisul, 787 José Acácio Moreira Tubarão Street, Tubarão 88704-900, Brazil
| | - Milton Carlos Kuga
- Department of Restorative Dentistry, School of Dentistry, Araraquara, São Paulo State University (UNESP), 1680 Humaitá Street, Araraquara 14801-903, Brazil
| | - João Felipe Besegato
- Department of Restorative Dentistry, School of Dentistry, Araraquara, São Paulo State University (UNESP), 1680 Humaitá Street, Araraquara 14801-903, Brazil
| | - Eliane Cristina Gulin de Oliveira
- Department of Restorative Dentistry, School of Dentistry, Araraquara, São Paulo State University (UNESP), 1680 Humaitá Street, Araraquara 14801-903, Brazil
| | - Thaís Piragine Leandrin
- Department of Restorative Dentistry, School of Dentistry, Araraquara, São Paulo State University (UNESP), 1680 Humaitá Street, Araraquara 14801-903, Brazil
| | - Marcus Vinicius Reis Só
- Department of Endodontics, School of Dentistry, University Federal of Rio Grande do Sul (UFRGS), Farroupilha, Porto Alegre 90010-150, Brazil
| | - João Carlos Silos Moraes
- Department of Physics and Chemistry, School of Natural Sciences and Engineering, Ilha Solteira, São Paulo State University (UNESP), 56 Brasil Avenue, Ilha Solteira 15385-000, Brazil
| | - Jefferson Ricardo Pereira
- Postgraduate Program in Health Sciences, University of Southern Santa Catarina–Unisul, 787 José Acácio Moreira Tubarão Street, Tubarão 88704-900, Brazil
- Correspondence: ; Tel.: +55-48-998564235
| |
Collapse
|
24
|
Kwaśny M, Polkowski J, Bombalska A. A Study on the Photopolymerization Kinetics of Selected Dental Resins Using Fourier Infrared Spectroscopy (FTIR). MATERIALS (BASEL, SWITZERLAND) 2022; 15:5850. [PMID: 36079232 PMCID: PMC9457181 DOI: 10.3390/ma15175850] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 08/19/2022] [Accepted: 08/21/2022] [Indexed: 06/15/2023]
Abstract
The aim of the presented study was a comparative analysis of the polymerization kinetics of dental resin-based composites currently used in dentistry in different environmental conditions (irradiance, activation time, layer thickness). The photopolymerization kinetics of eleven dental resins were investigated using a Woodpecker LED source. The DC was measured by FTIR in transmission mode and attenuated total reflection (ATR) from 5 s to 7 days. In the transmission mode, the spectra from parallel optical layers (about 0.2 mm thick) of samples placed between the KBr crystals were recorded. In the reflection mode, an ATR attachment with a diamond window was used. The DC calculation method was applied based on the application of a monomer absorption band at 1638 cm-1 (stretching vibration double bond C=C of the vinyl group) without using a reference band. The data were analyzed by performing an ANOVA test comparison between sample groups at the significance level α = 0.05. For all tested materials, the polymerization kinetics consist of three stages. The fastest stage occurs during the irradiation, and the achieved DC value is 70-75% of the maximum value 5 s after the irradiation. Another 15-20% DC increase at a moderate speed takes about 15-20 min. There is also a very slow further increase in DC of 5-10% within 5 days after irradiation. For 8 out of the 11 tested fillings, the optimal photopolymerization conditions are as follows: a power density of 400 or 1000 mW/cm2; an exposure time of 10 s; and a thickness of the irradiated resin layer of up to 2 mm. The influence of various conditions and factors on the reaction kinetics is dominant only in the early, rapid phase of the conversion. After longer times, the DC values gradually level out under different light conditions. The DC of the dental resins are dependent on the irradiance, light source, filler type, time after irradiance, and monomer thickness.
Collapse
Affiliation(s)
- Mirosław Kwaśny
- Institute of Optoelectronics, Military University of Technology, S. Kaliskiego 2 Str., 00-908 Warsaw, Poland
| | - Jakub Polkowski
- Faculty of Mechanical Engineering, Military University of Technology, S. Kaliskiego 2 Str., 00-908 Warsaw, Poland
| | - Aneta Bombalska
- Institute of Optoelectronics, Military University of Technology, S. Kaliskiego 2 Str., 00-908 Warsaw, Poland
| |
Collapse
|
25
|
Maucoski C, Price RB, Arrais CA, Sullivan B. Power output from 12 brands of contemporary LED light-curing units measured using 2 brands of radiometers. PLoS One 2022; 17:e0267359. [PMID: 35802759 PMCID: PMC9269870 DOI: 10.1371/journal.pone.0267359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 04/06/2022] [Indexed: 11/18/2022] Open
Abstract
Background Given the increasing use of photo-activated resins in dentistry, dentists and researchers need a user-friendly dental radiometer to measure the power output from dental light-curing units (LCUs). Objective Our goal was to measure the accuracy of two brands of dental radiometers in reporting the power (mW) from twelve brands of contemporary LCUs compared to a ‘gold standard’ (GS) reference value obtained from an integrating sphere attached to a fiberoptic spectroradiometer. Methods The power output was measured from two units of 12 brands of LCUs, five times on the ‘‘GS” system, five times on two Bluephase Meter II dental radiometers, and five times on two Mini Gig hand-held spectroradiometers. The emission spectrum was also recorded using the ‘GS’ integrating sphere. The power values reported by each meter were subjected to t-tests to compare the two examples of each LCU, and 3-way ANOVA followed by Bonferroni’s post-hoc tests. Regression analyses were also performed to determine the relationship between the data from the hand-held radiometers and the ‘GS’ integrating sphere. Results There was a large difference in the power values (mW) and the emission spectra from the 12 brands of LCUs on their standard-settings (p<0.001). Except for one LCU (Dental Spark @ 15.1%), the differences between the two LCUs of the same brand were less than 5.3% when measured using the ‘GS’ integrating sphere. Regression analyses showed a highly significant agreement between the power values reported from the two brands of radiometers and the ‘GS’ integrating sphere (R2 > 98%). Conclusion We concluded that the power values reported from both brands of dental radiometers we tested were accurate, provided that the light source did not emit wavelengths of light that were beyond the radiometer’s detection limit.
Collapse
Affiliation(s)
- Cristiane Maucoski
- Department of Restorative Dentistry, State University of Ponta Grossa, Ponta Grossa, Parana, Brazil
| | - Richard B. Price
- Department of Dental Clinical Sciences, Dalhousie University, Halifax, Nova Scotia, Canada
- * E-mail:
| | - Cesar A. Arrais
- Department of Restorative Dentistry, State University of Ponta Grossa, Ponta Grossa, Parana, Brazil
| | - Braden Sullivan
- Department of Dental Clinical Sciences, Dalhousie University, Halifax, Nova Scotia, Canada
| |
Collapse
|
26
|
Homogeneity of dental curing unit beam profile and its effect on microhardness of dental composites with varying thicknesses. Dent Mater 2022; 38:e231-e243. [PMID: 35717231 DOI: 10.1016/j.dental.2022.06.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Revised: 05/14/2022] [Accepted: 06/05/2022] [Indexed: 11/21/2022]
Abstract
OBJECTIVES The dental curing unit (DCU) has been reported to emit inhomogeneous light. However, there are no studies on which elements could affect the inhomogeneity of DCUs. This study aimed to analyze the effect of attenuating factors such as the aperture of the lens or neutral density (ND) filters on the DCU's beam profile and evaluate the effect of DCU's inhomogeneous beam profile on the microhardness distribution on composite resin specimens with different thicknesses. METHODS Radiant emittance and spectrum of eight DCUs were investigated with and without ND filters using different optical density (OD) values. Beam profiles of eight DCUs were photographed while increasing the OD values of the ND filter. The change in the beam profile while changing the f-number of the aperture and the OD value of the ND filters were recorded. The Vickers microhardness of Filtek Z350XT and SDR cured by Bluephase Style 20i with 1, 2, 3, and 4 mm specimens of nine points on each surface was measured. RESULTS Irradiance and spectrum of DCUs uniformly decreased after attenuation by the ND filters. The beam profile of the DCUs blurred when the f-number of the aperture was higher. The microhardness of Filtek Z350XT showed differences between the central and peripheral areas, and between the points under violet LED and the center on the bottom surface of the 4 mm specimen. The microhardness of the SDR did not show any differences. SIGNIFICANCE The inhomogeneity of the beam profile can be affected by attenuation conditions. DCU's inhomogeneous beam profile may have different effects on the composites depending on the thicknesses and types of composite resin used.
Collapse
|
27
|
Braga S, Schettini A, Carvalho E, Shimokawa C, Price RB, Soares CJ. Effect of the Sample Preparation and Light-curing Unit on the Microhardness and Degree of Conversion of Bulk-fill Resin-based Composite Restorations. Oper Dent 2022; 47:163-172. [PMID: 35604828 DOI: 10.2341/20-043-l] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/16/2020] [Indexed: 11/23/2022]
Abstract
OBJECTIVE To evaluate the effect of the sample preparation and light-curing units (LCUs) on the Knoop hardness (KH, N/mm2) and degree of conversion (DC, %) of bulk-fill resin-based composite restorations. METHODS Two molds were made using human molar teeth embedded in acrylic resin. One was a conventional tooth mold where the molar received a mesio-occluso-distal (MOD) preparation. In the other, the tooth was sectioned in three slices (buccal, middle, and lingual). The center slice received a MOD preparation similar to the conventional mold. Both tooth molds were placed in the second mandibular molar position in a Dentoform with a 44-mm interincisal opening. Restorations were made using Opus Bulk Fill (FGM) high viscosity bulk-fill resin-based composite (RBC) and light cured using two different lights: VALO Cordless (Ultradent) and Bluephase G2 (Ivoclar Vivadent). The RBC was placed in one increment that was light-cured for a total of 80 seconds (40 seconds at the occluso-mesial and occluso-distal locations). The RBC specimens were then prepared as follows: EmbPol - tooth mold specimen was embedded in polystyrene resin and polished before testing; Pol - tooth mold specimen was not embedded, but was polished before testing; NotPol - sectioned tooth mold, specimen not embedded nor polished before testing. The KH was measured in different depths and regions of the specimens, and the DC was measured using Raman spectroscopy. RESULTS The results were analyzed using a 2-way analysis of variance (ANOVA) or repeated measures followed by the Tukey posthoc test (α=0.05). The preparation method (p<0.001), depth of restoration (p<0.001), and the interaction between method and depth (p=0.003) all influenced the KH values. Preparation method (p<0.001), tooth region (p<0.001), and the interaction between method and tooth region (p=0.002) all influenced DC values. The KH values were reduced significantly from the top to the bottom of the restorations and also at the proximal box when compared with the occlusal region. This outcome was most significant in the proximal boxes. The NotPol method was the most effective method to detect the effect of differences in KH or DC within the restoration. A lower DC and KH were found at the gingival regions of the proximal boxes of the restorations. When the KH and DC values were compared, there were no significant differences between the LCUs (KH p=0.4 and DC p=0.317). CONCLUSION Preparation methods that embedded the samples in polystyrene resin and polished the specimens reduced the differences between the KH and DC values obtained by different preparation techniques. The NotPol method was better able to detect differences produced by light activation in deeper areas.
Collapse
Affiliation(s)
- Ssl Braga
- Stella Sueli Lourenço Braga, DDS, MSc, PhD, Department of Operative Dentistry and Dental Materials, Dental School, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil
| | - Act Schettini
- Ana Cecília Teodoro Schettini, DDS, Department of Operative Dentistry and Dental Materials, Dental School, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil
| | - Elo Carvalho
- Everton Luiz Oliveira Carvalho, DDS, Department of Operative Dentistry and Dental Materials, Dental School, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil
| | - Cak Shimokawa
- Carlos Alberto Kenji Shimokawa, DDS, MSc, PhD, professor, Department of Restorative Dentistry, Dental School, University of São Paulo, São Paulo, São Paulo, Brazil
| | - R B Price
- Richard Bengt Price, DDS, MSc, PhD, professor, Department of Dental Clinical Sciences, Dalhousie University, Halifax, Nova Scotia, Canada
| | - C J Soares
- *Carlos José Soares, DDS, MSc, PhD, Professor and Chair at Department of Operative Dentistry and Dental Materials, Dental School, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil
| |
Collapse
|
28
|
Depth of cure of 10 resin-based composites light-activated using a laser diode, multi-peak, and single-peak light-emitting diode curing lights. J Dent 2022; 122:104141. [PMID: 35483497 DOI: 10.1016/j.jdent.2022.104141] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 04/19/2022] [Accepted: 04/21/2022] [Indexed: 11/20/2022] Open
Abstract
OBJECTIVES To evaluate the depth of cure (DOC) of ten contemporary resin-based composites (RBCs), light-cured using different LCUs and exposure times. METHODS The power, radiant emittance, irradiance, radiant exposure (RE), and beam profiles from a laser (M, Monet), a multi-peak (V, Valo Grand), and single-peak (S, SmartLite Pro) LCU were measured. The DOC was measured using a 6-mm diameter metal mold and a solvent dissolution method to remove the uncured RBC. The length of the remaining RBC was divided by 2. The exposure times were: 1s and 3s for M, 10s and 20s for V, and 10s and 20s for S. Data were analyzed using: Bland-Altman distribution, Pearson's Correlation, and an artificial neural network (ANN) to establish the relative importance of the factors on the DOC (α=0.05; β=0.2). RESULTS Significant differences were found in the DOC of the different LCUs and composites. The laser LCU emitted the highest power, radiant emittance, and irradiance. However, this LCU used for 1 s delivered the lowest RE and produced the shortest DOC in all ten RBCs. The ANN demonstrated that the RE is the most critical factor for the DOC. Bland-Altman comparisons showed that the DOCs achieved with the laser LCU used for 1s were between 17 - 34 % shorter than the other conditions. CONCLUSIONS Although the laser LCU cured all 10 RBCs when used for 1s, it produced the shallowest DOC, and some RBCs did not achieve the minimum DOC threshold. The RE and not the irradiance was the most important factor in determining the DOC of RBCs. CLINICAL SIGNIFICANCE Despite delivering high power and irradiance, the laser used for l s delivered a lower radiant exposure than the conventional LCUs used for 10 s. This resulted in a shorter DOC.
Collapse
|
29
|
Mei W, Liu Q, Zhou H, Wang J. Preparation and UV curing properties of oxazolidinone-based acrylate derivatives. REACT FUNCT POLYM 2022. [DOI: 10.1016/j.reactfunctpolym.2022.105250] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
30
|
Bayarsaikhan E, Gu H, Hwangbo NK, Lim JH, Shim JS, Lee KW, Kim JE. Influence of different postcuring parameters on mechanical properties and biocompatibility of 3D printed crown and bridge resin for temporary restorations. J Mech Behav Biomed Mater 2022; 128:105127. [PMID: 35182913 DOI: 10.1016/j.jmbbm.2022.105127] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 02/08/2022] [Accepted: 02/08/2022] [Indexed: 11/25/2022]
Abstract
This study analyzed the flexural properties, Vickers hardness, degree of conversion (DC), and cell viability of 3D printed crown and bridge resin postcured using various types of postcuring equipment (PCE). 3D printed specimens were postcured for various times using different types of 3D printing PCE [for 5, 15, and 30 min using LC 3D Print Box (LC), Form Cure (FC), Cure M (CM), and Veltz 3D (VE) devices] and the VALO handheld light-curing (VA) device for 20, 40, and 60 s. Neither the flexural strength (132.27-145.79 MPa) nor the flexural modulus (1.52-1.83 GPa) differed significantly when postcuring for 30 min using the LC, FC, CM, or VE device, or for 20, 40, or 60 s of postcuring using the VA device (p > 0.05). The Vickers hardness was highest after 30 min of postcuring for all groups, and varied significantly with the postcuring time in the LC (p < 0.001) and CM (p < 0.001) groups. DC was significantly higher for the 5-min CM group (84.97 ± 4.02%) than for the GS, 30-min FC, 5-min VE, and 20-s VA groups. Cell viability of the postcured resin specimens was 56.46-92.29%, and varied significantly in the CM and VE groups according to the postcuring time (p < 0.05). Confocal laser scanning microscopy observations showed well-developed cell morphology and numerous cell-cell contacts in all groups except the GS group. This study found that the use of different types of PCE did not significantly affect the flexural properties of 3D printed crown and bridge resin, whereas there were significant variations in DC, Vickers hardness, and cell viability.
Collapse
Affiliation(s)
- Enkhjargal Bayarsaikhan
- Department of Prosthodontics, College of Dentistry, Yonsei University, Seoul, Republic of Korea
| | - Hanna Gu
- Department of Prosthodontics, College of Dentistry, Yonsei University, Seoul, Republic of Korea
| | - Na-Kyung Hwangbo
- Department of Orofacial and Oral Medicine, College of Dentistry, Yonsei University, Seoul, Republic of Korea
| | - Jung-Hwa Lim
- Department of Prosthodontics, College of Dentistry, Yonsei University, Seoul, Republic of Korea
| | - June-Sung Shim
- Department of Prosthodontics, College of Dentistry, Yonsei University, Seoul, Republic of Korea
| | - Keun-Woo Lee
- Dental Hospital, VHS Medical Center, Seoul, Republic of Korea
| | - Jong-Eun Kim
- Department of Prosthodontics, College of Dentistry, Yonsei University, Seoul, Republic of Korea.
| |
Collapse
|
31
|
Alavi FN, Darabi F, Salari A, Dehghan A. Effect of Light-Curing Unit Type and Bulk-Fill Composite Resins with Different Photoinitiators on Marginal Gaps of Class II Restorations. PESQUISA BRASILEIRA EM ODONTOPEDIATRIA E CLÍNICA INTEGRADA 2022. [DOI: 10.1590/pboci.2022.041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Affiliation(s)
| | | | | | - Arefeh Dehghan
- International branch of Guilan University of Medical Sciences, Iran
| |
Collapse
|
32
|
FRANK L, VIEIRA JUNIOR WF, BASTING RT, TURSSI CP, AMARAL FLBD, FRANÇA FMG. Effect of acid challenge and photoactivation distance on microhardness and roughness of flow bulk-fill composite resins. REVISTA DE ODONTOLOGIA DA UNESP 2022. [DOI: 10.1590/1807-2577.03222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Abstract Introduction composite resins are indicated to the reconstruction of proximal walls and the evaluation of properties of flow bulk-fill composite resins exposed to acid challenge is necessary. Objective to evaluate the microhardness and roughness at different depths of photoactivation of bulk-fill flow composites (Filtek Bulk Fill Flow; SureFil SDR Flow; Tetric N Ceram Bulk fill) and conventional composite resin (control, Filtek Z350 XT) subjected to acid challenge. Material and method forty composites brick shaped specimens (3x3x4 mm) were made using a polyacetal matrix. To simulate pH challenges, the samples were immersed in a demineralizing solution. Each sample had Knoop microhardness (KHN) and roughness (Ra) evaluated at three depths (superficial, medium, and cervical), considering the lateral surface of the sample. Data were submitted to Kruskal-Wallis, Friedman's and Dunn's tests with a significance level of 5%. Result comparing the composites among themselves, in superficial (p=0.693), medium (p=0.053) and cervical (p=0.176) regions, there was no difference in the KHN values. There were also no differences in roughness between the composites in superficial (p=0.356), medium (p=0.734) and cervical (p=0.207) regions. Only the Filtek Z350 XT (p=0.027) showed less difference in KHN in the middle region caused by acid challenge. Changes in roughness showed that the greatest difference was at the cervical region for Bulk Fill Flow SDR (p=0.014) and Tetric N-Ceram Bulk Fill (p = 0.003) with an increase after acid challenge. Conclusion after acid challenge, bulk-fill flow composites showed alterations similar to those presented by the conventional nanoparticulate resin composite.
Collapse
Affiliation(s)
- Luana FRANK
- Instituto de Pesquisas São Leopoldo Mandic, Brasil
| | | | | | | | | | | |
Collapse
|
33
|
Awad MM, Alradan M, Alshalan N, Alqahtani A, Alhalabi F, Salem MA, Rabah A, Alrahlah A. Placement of Posterior Composite Restorations: A Cross-Sectional Study of Dental Practitioners in Al-Kharj, Saudi Arabia. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph182312408. [PMID: 34886134 PMCID: PMC8656557 DOI: 10.3390/ijerph182312408] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 11/18/2021] [Accepted: 11/22/2021] [Indexed: 11/16/2022]
Abstract
Dental practitioner-related factors can affect the quality of composite restorations. This study aimed to investigate the clinical techniques used by dental practitioners (DPs) while placing direct posterior composite restorations. Methods: A questionnaire survey that sought information related to the placement of posterior composite restorations was delivered to 161 DPs working in the Al-Kharj area, Saudi Arabia. The collected data were statistically analyzed using Pearson’s Chi-square test and Fisher’s exact test considering the DP’s working sector and the answered questions. Results: A total of 123 DPs completed the survey (76.4% response rate). There was a statistically significant difference between DPs working in the private sector and those working in the governmental sector in 7 out of 17 questionnaire items namely: preparing a minimum depth of 2 mm, (p = 0.001); mechanical means of retention, (p = 0.003); operative field isolation, (p = 0.004); adhesive strategy, (p < 0.001); light-curing unit used, (p = 0.013); the use of radiometer, (p = 0.023), and dental matrix selection, (p < 0.001). Conclusion: The clinical techniques applied by DPs working in the private sector in Al-Kharj, Saudi Arabia when placing posterior composite restorations, including the specifications of cavity preparation, operative field isolation, and selection of the dental matrix system, may be substandard compared to those applied by DPs working in the governmental sector.
Collapse
Affiliation(s)
- Mohamed M. Awad
- Department of Conservative Dental Sciences, College of Dentistry, Prince Sattam Bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia; (F.A.); (M.A.S.)
- Correspondence: or (M.M.A.); (A.A.)
| | - Mansour Alradan
- College of Dentistry, Prince Sattam Bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia; (M.A.); (N.A.); (A.A.)
| | - Nawaf Alshalan
- College of Dentistry, Prince Sattam Bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia; (M.A.); (N.A.); (A.A.)
| | - Ali Alqahtani
- College of Dentistry, Prince Sattam Bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia; (M.A.); (N.A.); (A.A.)
| | - Feras Alhalabi
- Department of Conservative Dental Sciences, College of Dentistry, Prince Sattam Bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia; (F.A.); (M.A.S.)
| | - Mohammed Ali Salem
- Department of Conservative Dental Sciences, College of Dentistry, Prince Sattam Bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia; (F.A.); (M.A.S.)
| | - Ahmed Rabah
- Department of Prosthetic Dental Sciences, College of Dentistry, Prince Sattam Bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia;
| | - Ali Alrahlah
- Department of Restorative Dental Science, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia
- Engineer Abdullah Bugshan Research Chair for Dental and Oral Rehabilitation, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia
- Correspondence: or (M.M.A.); (A.A.)
| |
Collapse
|
34
|
De Angelis F, Vadini M, Capogreco M, D’Arcangelo C, D’Amario M. Effect of Light-Sources and Thicknesses of Composite Onlays on Micro-Hardness of Luting Composites. MATERIALS 2021; 14:ma14226849. [PMID: 34832251 PMCID: PMC8618162 DOI: 10.3390/ma14226849] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 11/10/2021] [Accepted: 11/11/2021] [Indexed: 11/18/2022]
Abstract
The aim of this study was to compare three different light-curing-units (LCUs) and determine their effectiveness in the adhesive cementation of indirect composite restorations when a light-curing resin cement is used. Two resin composites were selected: Enamel Plus HRI (Micerium) and AURA (SDI). Three thicknesses (3 mm, 4 mm and 5 mm) were produced and applied as overlays and underlays for each resin composite. A standardized composite layer was placed between underlay and overlay surfaces. Light curing of the resin-based luting composites was attained through the overlay filters using LCUs for different exposure times. All specimens were allocated to experimental groups according to the overlay thickness, curing unit and curing time. Vickers Hardness (VH) notches were carried out on each specimen. Data were statistically evaluated. The curing unit, curing time and overlay thickness were significant factors capable of influencing VH values. The results showed significantly decreased VH values with increasing specimen thickness (p < 0.05). Significant differences in VH values were found amongst the LCUs for the various exposure times (p < 0.05). According to the results, a time of cure shorter than 80 s (with a conventional quartz–tungsten–halogen LCU) or shorter than 40 s (with a high-power light-emitting diode (LED) LCU) is not recommended. The only subgroup achieving clinically acceptable VH values after a short 20 s curing time included the 3 mm-thick overlays made out of the AURA composite, when the high-power LED LCU unit was used (VH 51.0). Composite thickness has an intense effect on polymerization. In clinical practice, light-cured resin cements may result in insufficient polymerization for high thickness and inadequate times. High-intensity curing lights can attain the sufficient polymerization of resin cements through overlays in a significantly shorter time than conventional halogen light.
Collapse
Affiliation(s)
- Francesco De Angelis
- Unit of Restorative Dentistry and Endodontics, Department of Medical, Oral and Biotechnological Sciences, Dental School, “G. D’Annunzio” University of Chieti, 66100 Chieti, Italy; (F.D.A.); (C.D.)
| | - Mirco Vadini
- Unit of Restorative Dentistry and Endodontics, Department of Medical, Oral and Biotechnological Sciences, Dental School, “G. D’Annunzio” University of Chieti, 66100 Chieti, Italy; (F.D.A.); (C.D.)
- Correspondence:
| | - Mario Capogreco
- Unit of Restorative Dentistry, Endodontics and Oral Pathology, Dental Clinic, Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy; (M.C.); (M.D.)
| | - Camillo D’Arcangelo
- Unit of Restorative Dentistry and Endodontics, Department of Medical, Oral and Biotechnological Sciences, Dental School, “G. D’Annunzio” University of Chieti, 66100 Chieti, Italy; (F.D.A.); (C.D.)
| | - Maurizio D’Amario
- Unit of Restorative Dentistry, Endodontics and Oral Pathology, Dental Clinic, Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy; (M.C.); (M.D.)
| |
Collapse
|
35
|
Ilie N, Diegelmann J. Impact of ultra-fast (3 s) light-cure on cell toxicity and viscoelastic behavior in a dental resin-based composite with RAFT-mediated polymerization. J Mech Behav Biomed Mater 2021; 124:104810. [PMID: 34500355 DOI: 10.1016/j.jmbbm.2021.104810] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 08/31/2021] [Accepted: 09/02/2021] [Indexed: 11/17/2022]
Abstract
OBJECTIVE The aim of the study was to determine the effects of ultra-fast (3 s) light-curing on the viscoelastic behaviour at clinically relevant frequencies, and cell toxicity, in a resin-based composite (RBC) with reversible addition-fragmentation-chain transfer (RAFT) mediated polymerization. METHODS Three different protocols were used to cure cylindrical samples (height = 4 mm, ϴ = 5 mm), including ultra-fast (3s) cure with high radiant emittance, 10 s and 20 s cure with moderate radiant emittance. The properties of the light curing device were evaluated in all curing protocols by spectrophotometry up to an exposure distance of 10 mm. The light transmission through the samples was determined in real-time with the same spectrophotometer. Absorbance was calculated as a function of wavelength. The quasi-static (indentation hardness/HIT, indentation modulus/EIT) and viscoelastic (storage modulus/E', loss modulus/E″, loss factor/tan δ) material behavior was determined in an instrumented indentation test with a DMA (Dynamic Mechanical Analysis) module for 10 frequencies (0.5-5 Hz) by profiling the center of the samples in 330 μm steps from top to bottom. Cellular toxicity on human gingival fibroblast (HGF-1) was assessed using a WST-1 colorimetric assay after incubation time of up to 3 months. One and multiple-way analysis of variance (ANOVA) with Tukey honestly significant difference (HSD) post-hoc tests (α = 0.05) were applied. RESULTS The irradiance transmitted through a 4 mm high sample was less than 7% of the incident irradiance, and the absorbance was similar for all curing protocols, showing a decrease with wavelength. Similar quasi-static and viscoelastic parameters were observed regardless of the curing protocol. HIT increased slightly and EIT, E', E″ and tan δ decreased with frequency. Occasionally, slightly higher confidence intervals were observed for the ultra-fast curing group, which were related to a potential accumulation of stress. The curing protocol had no effect on cell viability (p = 0.326) but the eluate age (p < 0.001, ηP2 = 0.879) did. None of the groups showed cell toxicity at any point in time with respect to the corresponding negative control. CONCLUSIONS The ultra-fast curing with high irradiance induced no cell toxicity and an equivalent viscoelastic behavior as with conventional curing protocols in a RAFT-modified RBC.
Collapse
Affiliation(s)
- Nicoleta Ilie
- Department of Conservative Dentistry and Periodontology, University Hospital, LMU, Germany.
| | - Julia Diegelmann
- Department of Conservative Dentistry and Periodontology, University Hospital, LMU, Germany
| |
Collapse
|
36
|
Rocha MG, Oliveira D, Felix C, Roulet JF, Sinhoreti MAC, Correr AB. Beam Profiling of Dental Light Curing Units Using Different Camera-Based Systems. Eur J Dent 2021; 16:64-79. [PMID: 34450677 PMCID: PMC8890939 DOI: 10.1055/s-0041-1731628] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Objective
This study aimed to perform the beam profile of dental light-curing units (LCUs) using mirrorless and smartphone cameras and correlate it to a camera-based laser beam profiling system.
Materials and Methods
Three LCUs were evaluated (Radii Plus; Bluephase G2; and VALO Cordless). The spectral power of the LCUs was measured by using a spectrophotometer. The light emitted from the LCUs was projected onto a glass diffuser, and the images were recorded by using a mirrorless camera (NEX-F3), a smartphone (iPhone) and a camera-based beam profiler. Bandpass optical-filters were used, and for each LCU, the total spectral power output was integrated to calibrate the images. Statistical analysis was performed by digital image correlation (pixel by pixel) using Pearson’s correlation (α = 0.05; β = 0.2).
Results
The beam profile images showed nonuniform radiant emittance and spectral emission distributions across all the LCUs light tip. A strong correlation was found among cameras (Pearson’s r = 0.91 ± 0.03 with 95% confidence interval [CI]: 0.88–0.94 for the NEX-F3 and Pearson’s r = 0.88 ± 0.04 with 95% CI: 0.84–0.92 for the iPhone).
Conclusion
The standard Ophir beam profile system presented the most accurate distribution, but the mirrorless and smartphone cameras presented a strong correlation in the irradiance distribution of the beam profile images. Alternative cameras can be used to perform light beam profile of dental LCUs, but caution is needed as the type of sensor, image bit depth, and image processing are important to obtain accurate results.
Collapse
Affiliation(s)
- Mateus Garcia Rocha
- Department of Restorative Dental Sciences, Operative Dentistry Division, College of Dentistry, University of Florida, Florida, United States
| | - Dayane Oliveira
- Department of Restorative Dental Sciences, Operative Dentistry Division, College of Dentistry, University of Florida, Florida, United States
| | | | - Jean-François Roulet
- Department of Restorative Dental Sciences, Operative Dentistry Division, College of Dentistry, University of Florida, Florida, United States
| | - Mário Alexandre Coelho Sinhoreti
- Department of Restorative Dentistry, Dental Biomaterials Division, Piracicaba Dental School, State University of Campinas, Sao Paulo, Brazil
| | - Américo Bortolazzo Correr
- Department of Restorative Dentistry, Dental Biomaterials Division, Piracicaba Dental School, State University of Campinas, Sao Paulo, Brazil
| |
Collapse
|
37
|
Zarpellon DC, Runnacles P, Maucoski C, Gross DJ, Coelho U, Rueggeberg FA, Arrais C. In Vivo Pulp Temperature Changes During Class V Cavity Preparation and Resin Composite Restoration in Premolars. Oper Dent 2021; 46:374-384. [PMID: 34370040 DOI: 10.2341/20-098-c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/13/2020] [Indexed: 11/23/2022]
Abstract
OBJECTIVE This in vivo study evaluated the influence of the sequence of all restorative steps during Class V preparation and restoration in human premolars on pulp temperature (PT). METHODS AND MATERIALS Intact premolars with orthodontic extraction indication of 13 volunteers received infiltrative anesthesia and isolation with rubber dam. An occlusal preparation was made with a high-speed diamond bur under air-water spray until the pulp was minimally exposed, then a thermocouple probe was inserted within the pulp. A deep, 2.0-mm depth Class V preparation was made using a high-speed diamond bur under air-water spray. Three restorative techniques were performed (n=7): Filtek Z250 placed in two increments (10-second exposure, shade:A2, 3M ESPE, St. Paul, MN, USA), Filtek Z350 XT (40-second exposure, shade:A3D, 3M ESPE) and Tetric N Ceram Bulk Fill (10-second exposure, shade:IVA, Ivoclar Vivadent, Schaan, Liechtenstein), both placed in a single layer. Bonding layer and resin composite were exposed to light from the same Polywave LCU (Bluephase 20i, Ivoclar Vivadent). The peak PT and the difference between peak PT and baseline (ΔT) values were subjected to two-way, repeated measures analysis of variance (ANOVA), followed by the Bonferroni post-hoc test (α=0.05). RESULTS Cavity preparation and etch & rinse procedures decreased the PT values (p<0.001). The 40-second exposure of Filtek Z350 caused the highest peak PT values (38.7±0.8°C) and the highest ΔT values (3.4±0.8°C), while Tetric N Ceram Bulk Fill showed the lowest values (-1.6±1.3°C; p=0.009). CONCLUSION None of the evaluated procedures resulted in a PT rise near to values that could offer any risk of thermal damage to the pulp.
Collapse
|
38
|
Altaie A, Hadis MA, Wilson V, German MJ, Nattress BR, Wood D, Palin WM. An Evaluation of the Efficacy of LED Light Curing Units in Primary and Secondary Dental Settings in the United Kingdom. Oper Dent 2021; 46:271-282. [PMID: 34370026 DOI: 10.2341/20-092-lit] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/13/2020] [Indexed: 11/23/2022]
Abstract
OBJECTIVE This study aimed to evaluate the irradiance and the quality of LED light curing units (LCUs) in primary and secondary clinics in the UK and to assess the effect of damage, contamination, use of protective sleeves, and distance of light tips to target on the irradiance and performance of LCUs. METHODS The irradiance levels (mW/cm2) of 26 LED LCUs from general dental practices and 207 LED LCUs from two dental hospitals were measured using a digital radiometer (Blue Phase II, Ivoclar, Vivadent, Amherst, NY). Ten LED light guide tips (Satelec Mini, Acteon, Merignac, France) were selected to evaluate the effect of chipping, contamination (tip debris), and use of protective sleeves and tips to sensor distance on irradiance (mW/cm2) using a MARC Resin Calibrator (Blue Light Analytics, Halifax, Canada). Homogeneity of the light output was evaluated using a laser beam profiler (SP620; Ophir-Spiricon, North Longan, UT, USA). Statistical analysis was conducted using a one-way analysis of variance (ANOVA) with post hoc Tukey test (α=0.05) and linear regression with stepwise correlation tests. RESULTS Thirty-three percent of the LCUs delivered irradiance output less than 500 mW/cm2. The condition of the light curing tips was poor, with 16% contaminated with resin debris, 26% damaged, and 10% both contaminated and damaged. The irradiance output was significantly reduced in contaminated (62%) and chipped (50%) light curing tips and when using protective sleeves (24%) (p<0.05). Irradiance was also reduced when increasing the distance with 25% and 34% reduction at 7 mm and 10 mm, respectively (p<0.05). CONCLUSION There remains a lack of awareness of the need for regular monitoring and maintenance of dental LCUs. Damaged and contaminated light curing tips, use of protective sleeves, and increasing the distance from the restoration significantly reduced the irradiance output and the performance of the LCUs.
Collapse
|
39
|
Rummani G, Ide K, Hosaka K, Tichy A, Abdou A, Otsuki M, Nakajima M. Regional ultimate tensile strength and water sorption/solubility of bulk-fill and conventional resin composites: The effect of long-term water storage. Dent Mater J 2021; 40:1394-1402. [PMID: 34305051 DOI: 10.4012/dmj.2021-101] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The effect of long-term water storage on the regional ultimate tensile strength (UTS), water sorption (Wsp) and water solubility (Wsl) of conventional and bulk-fill resin composites at various depths was investigated. Composite specimens light-cured from one side were sectioned into beams corresponding to different depths (1-5 mm) and stored in water for 24 h, 1 week, 1 month, 6 months or 1 year. UTS increased during the first week and then gradually decreased over time, especially in deeper regions. Bulk-fill composites initially exhibited similar UTS at all depths, whereas the UTS of conventional composites at 1 mm and 5 mm differed significantly at all time points. Wsp and Wsl increased with depth and storage time, markedly at 3-5 mm after 1 month for conventional composites and after 6 months for bulk-fill composites. The signs of degradation at depths beyond 3 mm suggested that even bulk-fill composites have suboptimal properties in layers more than 3 mm in thickness.
Collapse
Affiliation(s)
- Ghassan Rummani
- Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Kurumi Ide
- Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Keiichi Hosaka
- Department of Regenerative Dental Medicine, Tokushima University Graduate School of Biomedical Sciences
| | - Antonin Tichy
- Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University.,Institute of Dental Medicine, First Faculty of Medicine of the Charles University and General University Hospital in Prague
| | - Ahmed Abdou
- Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University.,Biomaterials Department, Faculty of Dentistry, Modern University for Technology and Information
| | - Masayuki Otsuki
- Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Masatoshi Nakajima
- Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| |
Collapse
|
40
|
Knowledge and Attitude of Dental Clinicians towards Light-Curing Units: A Cross-Sectional Study. Int J Dent 2021; 2021:5578274. [PMID: 34234828 PMCID: PMC8219411 DOI: 10.1155/2021/5578274] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 06/05/2021] [Indexed: 11/18/2022] Open
Abstract
Objectives Light curing is crucial when applying composite resin restorations. Complete polymerization of the resin depends on delivering adequate light energy to it. Dental clinicians may be unaware of the importance of proper light-curing techniques. This study aimed at evaluating and comparing the level of knowledge of general practitioners (GPs) and specialists (SPs) regarding light-curing units. Materials and Methods An electronic survey was conducted online among GPs and SPs of various specialties, working in the governmental sector in Riyadh, Saudi Arabia. Collected data were analyzed for statistical significance. Results 310 dentists were included in the study. Nearly half of the GPs (45.9%) and more than half of SPs (56.8%) use light-emitting diode (LED) type light-curing units (LCUs). 36.9% of GPs and 29.6% of SPs were unsure about the type of LCUs they use in their dental clinics. 10.8% of GPs and 8.5% of SPs knew the proper term of the power output of LCU. 52.2% of the GPs and 55.7% of SPs were wrong about advancements in technology of LED LCUs. Regarding the use of radiometer, 48.2% of SPs and 35.1% of GPs had responded wrongly, and 37.7% of SPs and 52.3% of GPs were not familiar with the device, showing a statistical significance (p=0.040). There was no statistical significance observed in the responses pertaining to their years of experience, expected for two questions. Conclusion Both GPs and SPs displayed inadequate knowledge regarding the use of LCUs. Further educational programs are recommended to spread awareness about the handling of LCUs among dental clinicians.
Collapse
|
41
|
Kojic DD, El-Mowafy O, Price R, El-Badrawy W. The Ability of Dental Practitioners to Light-Cure Simulated Restorations. Oper Dent 2021; 46:160-172. [PMID: 34111286 DOI: 10.2341/19-147-c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/29/2020] [Indexed: 11/23/2022]
Abstract
CLINICAL RELEVANCE Using a patient simulator, dental professionals were tested to determine their ability to light-polymerize simulated restorations in their dental practice. After receiving specific instructions and training using the simulator, their ability to deliver sufficient light to polymerize restorations was significantly and substantially improved. SUMMARY Objectives: To determine the ability of dental professionals to deliver a radiant exposure of at least six J/cm2 in 10 seconds to simulated restorations.Methods and Materials: The study initially examined 113 light-emitting-diode (LED) light polymerization units (LPUs) used in dental offices to determine if they could deliver at least 6 J/cm2 radiant exposure (RE) in 10s. This assessment was completed by using a laboratory-grade light measuring device (checkMARC, BlueLight Analytics, Halifax, NS, Canada). The participating dental professionals whose LPUs could deliver 6 J/cm2 then used their own LPU to light-cure simulated anterior and posterior restorations in the MARC Patient Simulator (BlueLight Analytics). They then received specific instructions and were retested using the same LPUs. Data were statistically analyzed with a series of one-way analysis of variance (ANOVA), two-way ANOVA, paired-samples t-tests, Fisher post hoc multiple comparison tests, and McNemar tests with a preset alpha of 0.05 (SPSS Inc).Results: Ten (8.8%) LPUs could not deliver the required RE to the checkMARC in 10s and were eliminated from the study. For the anterior restoration, most dental practitioners (87.3%) could deliver at least 6 J/cm2 before instructions. After receiving additional light-curing instructions, only two (1.9%) participants were unable to deliver 6 J/cm2 to the anterior location. At the posterior location, only 55.3% (57) participants could deliver at least 6 J/cm2 before the instructions. After receiving these instructions, an additional 32 participants delivered at least 6 J/cm2. Overall, after receiving instructions on how to use the LPU correctly, the participants improved the amount of RE they delivered to anterior and posterior restorations by 22.5% and 30%, respectively.Conclusion: This study revealed that at the baseline, 44.7% of participating dental professionals failed to deliver 6 J/cm2 in 10s to the posterior simulated restoration when using their own LPU.
Collapse
|
42
|
Utilizing Light Cure Units: A Concise Narrative Review. Polymers (Basel) 2021; 13:polym13101596. [PMID: 34063428 PMCID: PMC8157231 DOI: 10.3390/polym13101596] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 05/11/2021] [Accepted: 05/11/2021] [Indexed: 01/19/2023] Open
Abstract
The use of photo-curable resin composite restorations is an essential treatment modality in modern dental practice. The success and longevity of these restorations depend on achieving predictable and effective polymerization. Understanding the dynamics of the polymerization and the effect of light cure units (LCUs) on this process is paramount. The goal of this concise narrative review is to provide a simplified presentation of basic principles of composite chemistry, polymerization reactions, and photo-curing with relevant terminologies. Clinical guidelines for choosing and maintaining LCUs, as well as safety precautions and factors under the control of the clinician are listed. Finally, clinical recommendations of LCUs’ usage and monitoring are included to aid practitioners in achieving predictable polymerization during the placement of direct resin composite restorations.
Collapse
|
43
|
Rocha MG, Roulet JF, Sinhoreti MAC, Correr AB, Oliveira D. Light Transmittance and Depth of Cure of a Bulk Fill Composite Based on the Exposure Reciprocity Law. Braz Dent J 2021; 32:78-84. [PMID: 33914006 DOI: 10.1590/0103-6440202103842] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 11/30/2020] [Indexed: 11/22/2022] Open
Abstract
The objective of this study was to evaluate the effect of the exposure reciprocity law of a multi-wave light-emitting diode (LED) on the light transmittance (LT), depth of cure (DOC) and degree of conversion in-depth (DC) of a bulk fill composite. A bulk fill composite (EvoCeram® bulk fill, Ivoclar Vivadent) was photoactivated using the multi-wave LED (VALO™ Cordless, Ultradent). The LED was previously characterized using a spectrophotometer to standardize the time of exposure when using the Standard or Xtra-Power modes with the same radiant exposure of 20J/cm2. LT was evaluated through samples of the bulk fill composite every millimeter till 4 mm in-depth. DOC was evaluated according to the ISO 4049. DC of the central longitudinal cross-section from each sample of the DOC test was mapped using FT-NIR microscopy. Data were statistically analyzed according to the experimental design (α=0.05; ß=0.2). The radiant exposure in the violet wavelength range for Standard and Xtra-Power was 4.5 and 5.0 J/cm2, respectively; for the blue wavelength range the radiant exposure for Standard and Xtra-Power was 15.5 and 15.0 J/cm2, respectively. There was no statistical difference in the DOC using Standard or Xtra-Power light-curing modes, but the DOC was lower than the claimed by the manufacturer (4 mm). The DC was not significantly affected by the light-curing mode up to 4 mm in depth (p>0.05). According to exposure reciprocity law, the reduction in exposure time using the same radiant exposure did not affect the depth of cure of the bulk fill composite.
Collapse
Affiliation(s)
- Mateus Garcia Rocha
- Department of Restorative Dental Sciences, Operative Dentistry Division, College of Dentistry, University of Florida, Gainesville, FL, USA
| | - Jean-François Roulet
- Department of Restorative Dental Sciences, Operative Dentistry Division, College of Dentistry, University of Florida, Gainesville, FL, USA
| | - Mario Alexandre Coelho Sinhoreti
- Department of Restorative Dentistry, Dental Materials Division, Piracicaba Dental School, UNICAMP - Universidade Estadual de Campinas, Piracicaba, SP, Brazil
| | - Américo Bortolazzo Correr
- Department of Restorative Dentistry, Dental Materials Division, Piracicaba Dental School, UNICAMP - Universidade Estadual de Campinas, Piracicaba, SP, Brazil
| | - Dayane Oliveira
- Department of Restorative Dental Sciences, Operative Dentistry Division, College of Dentistry, University of Florida, Gainesville, FL, USA
| |
Collapse
|
44
|
Ramos RQ, Moraes RR, Lopes GC. Effect of LED Light-Curing Spectral Emission Profile on Light-Cured Resin Cement Degree of Conversion. Oper Dent 2021; 46:63-74. [PMID: 33351938 DOI: 10.2341/19-234-l] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/27/2019] [Indexed: 11/23/2022]
Abstract
CLINICAL RELEVANCE The use of multipeak LED light-curing guarantees efficiency on light activation of Ivocerin-containing light-cured resin cement. SUMMARY
Collapse
|
45
|
Arana AFM, Justus B, DÁvila-SÁnchez A, Sugahara MDO, Coelho U, Farago PV, Arrais C. Influence of radiant exposure values from two third generation LED curing units on polymerization profile and microhardness of orthodontic composite under ceramic and metallic brackets. Dental Press J Orthod 2021; 26:e2119150. [PMID: 33729290 PMCID: PMC8018747 DOI: 10.1590/2177-6709.26.1.e2119150.oar] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 12/30/2019] [Indexed: 11/21/2022] Open
Abstract
INTRODUCTION Third generation of LED light curing units might be used in short exposure periods for orthodontic brackets bonding. OBJECTIVE This study evaluated the effect of the different radiant exposure (RE) values: Manufacturers' instructions (MI), ½ MI, 1/4 MI and Turbo mode. Two third-generation LED curing units were used: VALO® and Bluephase 20i® . The degree of conversion (DC) and Vickers hardness (VHN) of an orthodontic composite (OC) (Transbond XT) under metallic (MB) or ceramic brackets (CB) were measured. METHODS OC was applied to the bracket base, which was then placed over an attenuated total reflectance (ATR) table coupled to an infrared light spectroscope, or to a glass surface for the VHN analysis. The specimens were light-cured and DC values were calculated. The VHN was obtained in a microhardness tester. The data were analyzed with 2-way ANOVA followed by Tukey's post-hoc test (pre-set α=0.05). Linear regression analysis evaluated the relationship between RE values and dependent variables. RESULTS CB allowed higher DC and VHN values than MB (p< 0.001). No significant difference was noted among groups when CB were used. For MB, MI groups showed the highest DC and VHN values. A significant, but weak relationship was found between delivered RE values and dependent variables. CONCLUSIONS The decrease in RE values from third generation LED CU did not jeopardize the DC values when CB were used, but can compromise DC and VHN values when MB are used.
Collapse
Affiliation(s)
| | - Barbara Justus
- Universidade Estadual de Ponta Grossa, Departamento de Ciências Farmacêuticas (Ponta Grossa/PR, Brazil)
| | | | | | - Ulisses Coelho
- Universidade Estadual de Ponta Grossa, Departamento de Odontologia (Ponta Grossa/PR, Brazil)
| | - Paulo Vitor Farago
- Universidade Estadual de Ponta Grossa, Departamento de Ciências Farmacêuticas (Ponta Grossa/PR, Brazil)
| | - Cesar Arrais
- Universidade Estadual de Ponta Grossa, Departamento de Odontologia (Ponta Grossa/PR, Brazil)
| |
Collapse
|
46
|
Luca BI, Ilie N. Estimation of the tolerance threshold for the irradiance of modern LED curing units when simulating clinically relevant polymerization conditions. Dent Mater J 2021; 40:750-757. [PMID: 33678801 DOI: 10.4012/dmj.2020-261] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The study aims to characterize various LED light curing units (LED-LCU) in order to determine the tolerance threshold for varying the polymerization conditions. Two violet-blue and two blue LED-LCUs were analyzed by using a laboratory-grade spectrophotometer system. Fifty-five curing conditions were simulated in each LED-LCU by varying the position (centered and with an offset of 3-mm to the left, right, lower and upper direction) and the exposure distance (0 mm to 10 mm in 1-mm steps). Irradiance decreased with increasing exposure distance, while the effect of the LCU position was significant and LCU-specific. Only one LED-LCU enables the irradiance threshold of 1,000 mW/cm2 to be achieved in all positions up to an exposure distance of 4 mm. LCUs with a more homogeneous light beam profile more easily tolerate deviations from the ideal curing conditions. The study enables dentists to identify the limits of modern LED-LCUs and to estimate potential deviations from ideal curing conditions for clinically relevant situations.
Collapse
Affiliation(s)
- Bianca-Ioana Luca
- Department of Conservative Dentistry and Periodontology, University Hospital
| | - Nicoleta Ilie
- Department of Conservative Dentistry and Periodontology, University Hospital
| |
Collapse
|
47
|
Olmos-Olmos G, Teutle-Coyotecatl B, Román-Mendez CD, Carrasco-Gutiérrez R, González-Torres M, Contreras-Bulnes R, Rodríguez-Vilchis LE, de Los Angeles Moyaho-Bernal M. The influence of light-curing time on fluoride release, surface topography, and bacterial adhesion in resin-modified glass ionomer cements: AFM and SEM in vitro study. Microsc Res Tech 2021; 84:1628-1637. [PMID: 33580609 DOI: 10.1002/jemt.23723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 12/29/2020] [Accepted: 01/23/2021] [Indexed: 11/06/2022]
Abstract
Reinforced glass ionomer cements have been widely used in pediatric dentistry to prevent dental caries. However, the influence of biomaterial light-curing and its anti-cariogenic effects remain unclear. This study evaluates the influence of the light-curing time on fluoride release, surface topography, and bacterial adhesion in two types of resin-modified glass ionomer cements (RMGICs). One hundred disks were made, and samples were divided into two groups (n = 50 per group), according to each dental material (Vitremer™ and Ketac™ N100), and also divided into different light-cured times (10, 20, 30, 40, and 60 s). They were placed in phosphate-buffered saline solution (PBS) to measure the fluoride release. Subsequently, an independent sample of RMGICs per group was examined using atomic force microscopy (AFM). Four disks per group were incubated in a brain heart infusion (BHI) medium that was inoculated with Streptococcus mutans GS5 to evaluate the bacterial adhesion by 3-4, [5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide cell viability assay (MTT assay). The fluoride release was related to the light-curing time and gradually decreased as the light-curing time increased in both materials. Surface topography in Vitremer™ presents more irregular surfaces than Ketac™ N100. For S. mutans adhesion, the smallest number of cells per milliliter (cell/ml) was found at 40 s for Vitremer™ and at 30 s for Ketac™ N100. Thus, the shorter light-curing times allowed for major fluoride release in both materials. However, the RMGICs showed different patterns of bacterial adhesion according to the brand and light-curing time.
Collapse
Affiliation(s)
- Gabriela Olmos-Olmos
- Benemérita Universidad Autónoma de Puebla, Facultad de Estomatología, Academia de Odontología Pediátrica, Puebla, México
| | - Bernardo Teutle-Coyotecatl
- Universidad Autónoma del Estado de México, Facultad de Odontología, Centro de Investigación y Estudios Avanzados en Odontología (CIEAO), Toluca, Estado de México, Mexico
| | - Cristian D Román-Mendez
- Benemérita Universidad Autónoma de Puebla, Facultad de Estomatología, Laboratorio de Microbiología Oral, Puebla, México
| | - Rosendo Carrasco-Gutiérrez
- Benemérita Universidad Autónoma de Puebla, Facultad de Estomatología, Academia de Odontología Pediátrica, Puebla, México
| | - Maykel González-Torres
- Conacyt-Laboratorio de Biotecnología, Instituto Nacional de Rehabilitación "Luis Guillermo Ibarra", Ciudad de Mexico, Mexico
| | - Rosalía Contreras-Bulnes
- Universidad Autónoma del Estado de México, Facultad de Odontología, Centro de Investigación y Estudios Avanzados en Odontología (CIEAO), Toluca, Estado de México, Mexico
| | - Laura E Rodríguez-Vilchis
- Universidad Autónoma del Estado de México, Facultad de Odontología, Centro de Investigación y Estudios Avanzados en Odontología (CIEAO), Toluca, Estado de México, Mexico
| | | |
Collapse
|
48
|
Pang Y, Shiraishi A, Keil D, Popov S, Strehmel V, Jiao H, Gutmann JS, Zou Y, Strehmel B. NIR-Sensitized Cationic and Hybrid Radical/Cationic Polymerization and Crosslinking. Angew Chem Int Ed Engl 2021; 60:1465-1473. [PMID: 32964609 PMCID: PMC7839698 DOI: 10.1002/anie.202010746] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Indexed: 12/21/2022]
Abstract
NIR‐sensitized cationic polymerization proceeded with good efficiency, as was demonstrated with epoxides, vinyl ether, and oxetane. A heptacyanine functioned as sensitizer while iodonium salt served as coinitiator. The anion adopts a special function in a series selected from fluorinated phosphates (a: [PF6]−, b: [PF3(C2F5)3]−, c: [PF3(n‐C4F9)3]−), aluminates (d: [Al(O‐t‐C4F9)4]−, e: [Al(O(C3F6)CH3)4]−), and methide [C(O‐SO2CF3)3]− (f). Vinyl ether showed the best cationic polymerization efficiency followed by oxetanes and oxiranes. DFT calculations provided a rough pattern regarding the electrostatic potential of each anion where d showed a better reactivity than e and b. Formation of interpenetrating polymer networks (IPNs) using trimethylpropane triacrylate and epoxides proceeded in the case of NIR‐sensitized polymerization where anion d served as counter ion in the initiator system. No IPN was formed by UV‐LED initiation using the same monomers but thioxanthone/iodonium salt as photoinitiator. Exposure was carried out with new NIR‐LED devices emitting at either 805 or 870 nm.
Collapse
Affiliation(s)
- Yulian Pang
- Department of Chemistry, Institute for Coatings and Surface Chemistry, Niederrhein University of Applied Sciences, Adlerstr. 1, 47798, Krefeld, Germany.,College of Chemistry, Beijing Normal University, No. 19, Xinjiekouwai St. Haidian District, Beijing, 100875, P. R. China
| | - Atsushi Shiraishi
- San-Apro Ltd., 1-40, Goryo-Ohara, Nishikyoku, Kyoto, 615-8245, Japan
| | - Dietmar Keil
- FEW Chemicals GmbH, Technikumstraße 1, 06766, Bitterfeld-Wolfen, Germany
| | - Sergey Popov
- Spectrum Info Ltd., Murmanskaya 5, 02094, Kyiv, Ukraine
| | - Veronika Strehmel
- Department of Chemistry, Institute for Coatings and Surface Chemistry, Niederrhein University of Applied Sciences, Adlerstr. 1, 47798, Krefeld, Germany
| | - Hongjun Jiao
- Hubei Gurun Technology Co., LTD., Jingmen Chemical Recycling Industrial Park, 448000, Jingmen, Hubei Province, P. R. China
| | - Jochen S Gutmann
- Department of Physical Chemistry and Center of Nanointegration (CENIDE), University of Duisburg-Essen, Universitätsstr. 7, 45141, Essen, Germany
| | - Yingquan Zou
- College of Chemistry, Beijing Normal University, No. 19, Xinjiekouwai St. Haidian District, Beijing, 100875, P. R. China
| | - Bernd Strehmel
- Department of Chemistry, Institute for Coatings and Surface Chemistry, Niederrhein University of Applied Sciences, Adlerstr. 1, 47798, Krefeld, Germany
| |
Collapse
|
49
|
Pang Y, Shiraishi A, Keil D, Popov S, Strehmel V, Jiao H, Gutmann JS, Zou Y, Strehmel B. NIR‐sensibilisierte kationische und hybride radikalische/kationische Polymerisation und Vernetzung. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202010746] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Yulian Pang
- Fachbereich Chemie Institut für Lacke und Oberflächenchemie Hochschule Niederrhein Adlerstraße 1 47798 Krefeld Deutschland
- College of Chemistry Beijing Normal University No. 19, Xinjiekouwai St. Haidian District Beijing 100875 VR China
| | | | - Dietmar Keil
- FEW Chemicals GmbH Technikumstraße 1 06766 Bitterfeld-Wolfen Deutschland
| | - Sergey Popov
- Spectrum Info Ltd. Murmanskaya 5 02094 Kyiv Ukraine
| | - Veronika Strehmel
- Fachbereich Chemie Institut für Lacke und Oberflächenchemie Hochschule Niederrhein Adlerstraße 1 47798 Krefeld Deutschland
| | - Hongjun Jiao
- Hubei Gurun Technology Co., LTD. Jingmen Chemical Recycling Industrial Park 448000 Jingmen Hubei Province VR China
| | - Jochen S. Gutmann
- Institut für Physikalische Chemie und Center for Nanointegration Duisburg-Essen (CENIDE) Universität Duisburg-Essen Universitätsstraße 7 45141 Essen Deutschland
| | - Yingquan Zou
- College of Chemistry Beijing Normal University No. 19, Xinjiekouwai St. Haidian District Beijing 100875 VR China
| | - Bernd Strehmel
- Fachbereich Chemie Institut für Lacke und Oberflächenchemie Hochschule Niederrhein Adlerstraße 1 47798 Krefeld Deutschland
| |
Collapse
|
50
|
Durable Oral Biofilm Resistance of 3D-Printed Dental Base Polymers Containing Zwitterionic Materials. Int J Mol Sci 2021; 22:ijms22010417. [PMID: 33401545 PMCID: PMC7795277 DOI: 10.3390/ijms22010417] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 12/21/2020] [Accepted: 12/30/2020] [Indexed: 12/28/2022] Open
Abstract
Poly(methyl methacralyate) (PMMA) has long been used in dentistry as a base polymer for dentures, and it is recently being used for the 3D printing of dental materials. Despite its many advantages, its susceptibility to microbial colonization remains to be overcome. In this study, the interface between 3D-printed PMMA specimens and oral salivary biofilm was studied following the addition of zwitterionic materials, 2-methacryloyloxyethyl phosphorylcholine (MPC) or sulfobetaine methacrylate (SB). A significant reduction in bacterial and biofilm adhesions was observed following the addition of MPC or SB, owing to their protein-repellent properties, and there were no significant differences between the two test materials. Although the mechanical properties of the tested materials were degraded, the statistical value of the reduction was minimal and all the properties fulfilled the requirements set by the International Standard, ISO 20795-2. Additionally, both the test materials maintained their resistance to biofilm when subjected to hydrothermal fatigue, with no further deterioration of the mechanical properties. Thus, novel 3D-printable PMMA incorporated with MPC or SB shows durable oral salivary biofilm resistance with maintenance of the physical and mechanical properties.
Collapse
|