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Haugen HJ, Ma Q, Linskens S, Par M, Mandic VN, Mensikova E, Nogueira LP, Taubock TT, Attin T, Gubler A, Leeuwenburgh S, de Beeck MO, Marovic D. 3D micro-CT and O-PTIR spectroscopy bring new understanding of the influence of filler content in dental resin composites. Dent Mater 2024:S0109-5641(24)00267-7. [PMID: 39277488 DOI: 10.1016/j.dental.2024.09.001] [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: 05/20/2024] [Revised: 08/16/2024] [Accepted: 09/10/2024] [Indexed: 09/17/2024]
Abstract
BACKGROUND Dental resin composites' performance is intricately linked to their polymerisation shrinkage characteristics. This study compares polymerisation shrinkage using advanced 3D micro-computed tomography (micro-CT) and traditional 2D linear assessments. It delves into the crucial role of filler content on shrinkage and the degree of conversion in dental resin composites, providing valuable insights for the field. METHODS Five experimental dental composite materials were prepared with increasing filler contents (55-75 wt%) and analysed using either 3D micro-CT for volumetric shrinkage or a custom-designed linometer for 2D linear shrinkage. The degree of conversion was assessed using Optical Photothermal Infrared (O-PTIR) and Fourier-Transform Infrared (FTIR) spectroscopy. Light transmittance through a 2-mm layer was evaluated using a NIST-calibrated spectrometer. Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray Spectroscopy (EDX) examined surface morphology and elemental distribution. Correlation between the investigated parameters was determined using Spearman correlation analyses. RESULTS The study found significant differences in polymerisation-related properties among different filler content categories, with volumetric shrinkage consistently demonstrating higher mean values than linear shrinkage across most groups. Volumetric shrinkage decreased with increasing curing depth, showing no direct correlation between filler content and shrinkage levels at different curing depths. The results highlighted a strong negative correlation between filler content and degree of conversion, volumetric and linear shrinkage, as well as maximum shrinkage rate. Light transmittance showed a moderate correlation with the filler content and a weak correlation with other tested parameters. CONCLUSIONS This study underscores the importance of considering both volumetric and linear shrinkage in the design and analysis of dental composite materials. The findings advocate optimising filler content to minimise shrinkage and enhance material performance. Integrating micro-CT and O-PTIR techniques offers novel insights into dental composites' polymerisation behaviour, providing a foundation for future research to develop materials with improved clinical outcomes.
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Affiliation(s)
- Håvard J Haugen
- Department of Biomaterials Institute of Clinical Dentistry, University of Oslo, Norway.
| | - Qianli Ma
- Department of Biomaterials Institute of Clinical Dentistry, University of Oslo, Norway
| | - Stefanie Linskens
- Department of Biomaterials Institute of Clinical Dentistry, University of Oslo, Norway; Department of Dentistry - Regenerative Biomaterials, Radboud University Medical Center, Philips van Leydenlaan 25, 6525 EX Nijmegen, the Netherlands
| | - Matej Par
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Croatia
| | - Visnja Negovetic Mandic
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Croatia
| | - Emile Mensikova
- Department of Biomaterials Institute of Clinical Dentistry, University of Oslo, Norway
| | - Liebert P Nogueira
- Oral Research Laboratory, Institute of Clinical Dentistry, University of Oslo, Norway
| | - Tobias T Taubock
- Clinic of Conservative and Preventive Dentistry, Center for Dental Medicine, University of Zurich, 8032 Zurich, Switzerland
| | - Thomas Attin
- Clinic of Conservative and Preventive Dentistry, Center for Dental Medicine, University of Zurich, 8032 Zurich, Switzerland
| | - Andrea Gubler
- Clinic of Conservative and Preventive Dentistry, Center for Dental Medicine, University of Zurich, 8032 Zurich, Switzerland
| | - Sander Leeuwenburgh
- Department of Dentistry - Regenerative Biomaterials, Radboud University Medical Center, Philips van Leydenlaan 25, 6525 EX Nijmegen, the Netherlands
| | | | - Danijela Marovic
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Croatia
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Fidalgo-Pereira R, Carvalho Ó, Catarino SO, Henriques B, Torres O, Braem A, Souza JCM. Effect of inorganic fillers on the light transmission through traditional or flowable resin-matrix composites for restorative dentistry. Clin Oral Investig 2023; 27:5679-5693. [PMID: 37592003 PMCID: PMC10492747 DOI: 10.1007/s00784-023-05189-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 07/28/2023] [Indexed: 08/19/2023]
Abstract
OBJECTIVES The aim of this in vitro study was to evaluate the light transmission through five different resin-matrix composites regarding the inorganic filler content. METHODS Resin-matrix composite disc-shaped specimens were prepared on glass molds. Three traditional resin-matrix composites contained inorganic fillers at 74, 80, and 89 wt. % while two flowable composites revealed 60 and 62.5 wt. % inorganic fillers. Light transmission through the resin-matrix composites was assessed using a spectrophotometer with an integrated monochromator before and after light curing for 10, 20, or 40s. Elastic modulus and nanohardness were evaluated through nanoindentation's tests, while Vicker's hardness was measured by micro-hardness assessment. Chemical analyses were performed by FTIR and EDS, while microstructural analysis was conducted by optical microscopy and scanning electron microscopy. Data were evaluated using two-way ANOVA and Tukey's test (p < 0.05). RESULTS After polymerization, optical transmittance increased for all specimens above 650-nm wavelength irradiation since higher light exposure time leads to increased light transmittance. At 20- or 40-s irradiation, similar light transmittance was recorded for resin composites with 60, 62, 74, or 78-80 wt. % inorganic fillers. The lowest light transmittance was recorded for a resin-matrix composite reinforced with 89 wt. % inorganic fillers. Thus, the size of inorganic fillers ranged from nano- up to micro-scale dimensions and the high content of micro-scale inorganic particles can change the light pathway and decrease the light transmittance through the materials. At 850-nm wavelength, the average ratio between polymerized and non-polymerized specimens increased by 1.6 times for the resin composite with 89 wt. % fillers, while the composites with 60 wt. % fillers revealed an increased ratio by 3.5 times higher than that recorded at 600-nm wavelength. High mean values of elastic modulus, nano-hardness, and micro-hardness were recorded for the resin-matrix composites with the highest inorganic content. CONCLUSIONS A high content of inorganic fillers at 89 wt.% decreased the light transmission through resin-matrix composites. However, certain types of fillers do not interfere on the light transmission, maintaining an optimal polymerization and the physical properties of the resin-matrix composites. CLINICAL SIGNIFICANCE The type and content of inorganic fillers in the chemical composition of resin-matrix composites do affect their polymerization mode. As a consequence, the clinical performance of resin-matrix composites can be compromised, leading to variable physical properties and degradation.
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Affiliation(s)
- Rita Fidalgo-Pereira
- Center for Interdisciplinary Research in Health (CIIS), Faculty of Dental Medicine (FMD), Universidade Católica Portuguesa (UCP), 3504-505, Viseu, Portugal
- University Institute of Health Sciences (IUCS), CESPU, 4585-116, Gandra PRD, Portugal
| | - Óscar Carvalho
- Center for MicroElectroMechanical Systems (CMEMS-UMINHO), University of Minho, 4800-058, Guimarães, Portugal
- LABBELS Associate Laboratory, University of Minho, Guimarães, 4710-057, Braga, Portugal
| | - Susana O Catarino
- Center for MicroElectroMechanical Systems (CMEMS-UMINHO), University of Minho, 4800-058, Guimarães, Portugal
- LABBELS Associate Laboratory, University of Minho, Guimarães, 4710-057, Braga, Portugal
| | - Bruno Henriques
- Center for MicroElectroMechanical Systems (CMEMS-UMINHO), University of Minho, 4800-058, Guimarães, Portugal
- LABBELS Associate Laboratory, University of Minho, Guimarães, 4710-057, Braga, Portugal
- Ceramic and Composite Materials Research Group (CERMAT), Department of Mechanical Engineering (EMC), Federal University of Santa Catarina (UFSC), SC, 88040-900, Florianopolis, Brazil
| | - Orlanda Torres
- Oral Pathology and Rehabilitation Research Unit (UNIPRO), University Institute of Health Sciences (IUCS), CESPU, 4585-116, Gandra, Portugal
| | - Annabel Braem
- Department of Materials Engineering (MTM), Biomaterials and Tissue Engineering Research Group, KU Leuven, 3000, Leuven, Belgium
| | - Júlio C M Souza
- Center for MicroElectroMechanical Systems (CMEMS-UMINHO), University of Minho, 4800-058, Guimarães, Portugal.
- LABBELS Associate Laboratory, University of Minho, Guimarães, 4710-057, Braga, Portugal.
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Fidalgo-Pereira R, Torres O, Carvalho Ó, Silva FS, Catarino SO, Özcan M, Souza JCM. A Scoping Review on the Polymerization of Resin-Matrix Cements Used in Restorative Dentistry. MATERIALS (BASEL, SWITZERLAND) 2023; 16:1560. [PMID: 36837188 PMCID: PMC9961405 DOI: 10.3390/ma16041560] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 02/08/2023] [Accepted: 02/09/2023] [Indexed: 06/18/2023]
Abstract
In dentistry, clinicians mainly use dual-cured or light-cured resin-matrix cements to achieve a proper polymerization of the organic matrix leading to enhanced physical properties of the cement. However, several parameters can affect the polymerization of resin-matrix cements. The main aim of the present study was to perform a scoping review on the degree of conversion (DC) of the organic matrix, the polymerization, and the light transmittance of different resin-matrix cements used in dentistry. A search was performed on PubMed using a combination of the following key terms: degree of conversion, resin cements, light transmittance, polymerization, light curing, and thickness. Articles in the English language published up to November 2022 were selected. The selected studies' results demonstrated that restorative structures with a thickness higher than 1.5 mm decrease the light irradiance towards the resin-matrix cement. A decrease in light transmission provides a low energy absorption through the resin cement leading to a low DC percentage. On the other hand, the highest DC percentages, ranging between 55 and 75%, have been reported for dual-cured resin-matrix cements, although the polymerization mode and exposure time also influence the DC of monomers. Thus, the polymerization of resin-matrix cements can be optimized taking into account different parameters of light-curing, such as adequate light distance, irradiance, exposure time, equipment, and wavelength. Then, optimum physical properties are achieved that provide a long-term clinical performance of the cemented restorative materials.
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Affiliation(s)
- Rita Fidalgo-Pereira
- University Institute of Health Sciences (IUCS), CESPU, 4585-116 Gandra, Portugal
- Center for Interdisciplinary Research in Health (CIIS), Faculty of Dental Medicine (FMD), Universidade Católica Portuguesa (UCP), 3504-505 Viseu, Portugal
| | - Orlanda Torres
- University Institute of Health Sciences (IUCS), CESPU, 4585-116 Gandra, Portugal
| | - Óscar Carvalho
- Center for MicroElectroMechanical Systems (CMEMS-UMINHO), University of Minho, Campus Azurém, 4800-058 Guimarães, Portugal
- LABBELS Associate Laboratory, University of Minho, 4805-017 Guimarães, Portugal
| | - Filipe S. Silva
- Center for MicroElectroMechanical Systems (CMEMS-UMINHO), University of Minho, Campus Azurém, 4800-058 Guimarães, Portugal
- LABBELS Associate Laboratory, University of Minho, 4805-017 Guimarães, Portugal
| | - Susana O. Catarino
- Center for MicroElectroMechanical Systems (CMEMS-UMINHO), University of Minho, Campus Azurém, 4800-058 Guimarães, Portugal
- LABBELS Associate Laboratory, University of Minho, 4805-017 Guimarães, Portugal
| | - Mutlu Özcan
- Division of Dental Biomaterials, Center of Dental Medicine, Clinic of Reconstructive Dentistry, University of Zurich, 8032 Zurich, Switzerland
| | - Júlio C. M. Souza
- University Institute of Health Sciences (IUCS), CESPU, 4585-116 Gandra, Portugal
- Center for MicroElectroMechanical Systems (CMEMS-UMINHO), University of Minho, Campus Azurém, 4800-058 Guimarães, Portugal
- LABBELS Associate Laboratory, University of Minho, 4805-017 Guimarães, Portugal
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Marovic D, Par M, Tauböck TT, Haugen HJ, Negovetic Mandic V, Wüthrich D, Burrer P, Zheng K, Attin T, Tarle Z, Boccaccini AR. Impact of Copper-Doped Mesoporous Bioactive Glass Nanospheres on the Polymerisation Kinetics and Shrinkage Stress of Dental Resin Composites. Int J Mol Sci 2022; 23:ijms23158195. [PMID: 35897771 PMCID: PMC9332616 DOI: 10.3390/ijms23158195] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 07/21/2022] [Accepted: 07/22/2022] [Indexed: 12/24/2022] Open
Abstract
We embedded copper-doped mesoporous bioactive glass nanospheres (Cu-MBGN) with antibacterial and ion-releasing properties into experimental dental composites and investigated the effect of Cu-MBGN on the polymerisation properties. We prepared seven composites with a BisGMA/TEGDMA (60/40) matrix and 65 wt.% total filler content, added Cu-MBGN or a combination of Cu-MBGN and silanised silica to the silanised barium glass base, and examined nine parameters: light transmittance, degree of conversion (DC), maximum polymerisation rate (Rmax), time to reach Rmax, linear shrinkage, shrinkage stress (PSS), maximum PSS rate, time to reach maximum PSS rate, and depth of cure. Cu-MBGN without silica accelerated polymerisation, reduced light transmission, and had the highest DC (58.8 ± 0.9%) and Rmax (9.8 ± 0.2%/s), but lower shrinkage (3 ± 0.05%) and similar PSS (0.89 ± 0.07 MPa) versus the inert reference (0.83 ± 0.13 MPa). Combined Cu-MBGN and silica slowed the Rmax and achieved a similar DC but resulted in higher shrinkage. However, using a combined 5 wt.% Cu-MBGN and silica, the PSS resembled that of the inert reference. The synergistic action of 5 wt.% Cu-MBGN and silanised silica in combination with silanised barium glass resulted in a material with the highest likelihood for dental applications in future.
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Affiliation(s)
- Danijela Marovic
- Department of Endodontics and Restorative Dentistry, University of Zagreb, 10000 Zagreb, Croatia; (V.N.M.); (Z.T.)
- Correspondence: (D.M.); (M.P.); Tel.: +385-14899203 (D.M. & M.P.)
| | - Matej Par
- Department of Endodontics and Restorative Dentistry, University of Zagreb, 10000 Zagreb, Croatia; (V.N.M.); (Z.T.)
- Correspondence: (D.M.); (M.P.); Tel.: +385-14899203 (D.M. & M.P.)
| | - Tobias T. Tauböck
- Department of Conservative and Preventive Dentistry, Centre for Dental Medicine, University of Zurich, 8032 Zurich, Switzerland; (T.T.T.); (D.W.); (P.B.); (T.A.)
| | - Håvard J. Haugen
- Department of Biomaterials, Institute of Clinical Dentistry, University of Oslo, 0317 Oslo, Norway;
| | - Visnja Negovetic Mandic
- Department of Endodontics and Restorative Dentistry, University of Zagreb, 10000 Zagreb, Croatia; (V.N.M.); (Z.T.)
| | - Damian Wüthrich
- Department of Conservative and Preventive Dentistry, Centre for Dental Medicine, University of Zurich, 8032 Zurich, Switzerland; (T.T.T.); (D.W.); (P.B.); (T.A.)
| | - Phoebe Burrer
- Department of Conservative and Preventive Dentistry, Centre for Dental Medicine, University of Zurich, 8032 Zurich, Switzerland; (T.T.T.); (D.W.); (P.B.); (T.A.)
| | - Kai Zheng
- Engineering Research Center of Stomatological Translational Medicine, Nanjing Medical University, Nanjing 210029, China;
| | - Thomas Attin
- Department of Conservative and Preventive Dentistry, Centre for Dental Medicine, University of Zurich, 8032 Zurich, Switzerland; (T.T.T.); (D.W.); (P.B.); (T.A.)
| | - Zrinka Tarle
- Department of Endodontics and Restorative Dentistry, University of Zagreb, 10000 Zagreb, Croatia; (V.N.M.); (Z.T.)
| | - Aldo R. Boccaccini
- Department of Materials Science and Engineering, Institute of Biomaterials, University of Erlangen-Nuremberg, 91058 Erlangen, Germany;
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Dorozhkin SV. Synthetic amorphous calcium phosphates (ACPs): preparation, structure, properties, and biomedical applications. Biomater Sci 2021; 9:7748-7798. [PMID: 34755730 DOI: 10.1039/d1bm01239h] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Amorphous calcium phosphates (ACPs) represent a metastable amorphous state of other calcium orthophosphates (abbreviated as CaPO4) possessing variable compositional but rather identical glass-like physical properties, in which there are neither translational nor orientational long-range orders of the atomic positions. In nature, ACPs of a biological origin are found in the calcified tissues of mammals, some parts of primitive organisms, as well as in the mammalian milk. Manmade ACPs can be synthesized in a laboratory by various methods including wet-chemical precipitation, in which they are the first solid phases, precipitated after a rapid mixing of aqueous solutions containing dissolved ions of Ca2+ and PO43- in sufficient amounts. Due to the amorphous nature, all types of synthetic ACPs appear to be thermodynamically unstable and, unless stored in dry conditions or doped by stabilizers, they tend to transform spontaneously to crystalline CaPO4, mainly to ones with an apatitic structure. This intrinsic metastability of the ACPs is of a great biological relevance. In particular, the initiating role that metastable ACPs play in matrix vesicle biomineralization raises their importance from a mere laboratory curiosity to that of a reasonable key intermediate in skeletal calcifications. In addition, synthetic ACPs appear to be very promising biomaterials both for manufacturing artificial bone grafts and for dental applications. In this review, the current knowledge on the occurrence, structural design, chemical composition, preparation, properties, and biomedical applications of the synthetic ACPs have been summarized.
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Farooq I, Ali S, Al-Saleh S, AlHamdan EM, AlRefeai MH, Abduljabbar T, Vohra F. Synergistic Effect of Bioactive Inorganic Fillers in Enhancing Properties of Dentin Adhesives-A Review. Polymers (Basel) 2021; 13:polym13132169. [PMID: 34209016 PMCID: PMC8271823 DOI: 10.3390/polym13132169] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 06/23/2021] [Accepted: 06/25/2021] [Indexed: 02/07/2023] Open
Abstract
Dentin adhesives (DAs) play a critical role in the clinical success of dental resin composite (DRC) restorations. A strong bond between the adhesive and dentin improves the longevity of the restoration, but it is strongly dependent on the various properties of DAs. The current review was aimed at summarizing the information present in the literature regarding the improvement of the properties of DAs noticed after the addition of bioactive inorganic fillers. From our search, we were able to find evidence of multiple bioactive inorganic fillers (bioactive glass, hydroxyapatite, amorphous calcium phosphate, graphene oxide, calcium chloride, zinc chloride, silica, and niobium pentoxide) in the literature that have been used to improve the different properties of DAs. These improvements can be seen in the form of improved hardness, higher modulus of elasticity, enhanced bond, flexural, and ultimate tensile strength, improved fracture toughness, reduced nanoleakage, remineralization of the adhesive-dentin interface, improved resin tag formation, greater radiopacity, antibacterial effect, and improved DC (observed for some fillers). Most of the studies dealing with the subject area are in vitro. Future in situ and in vivo studies are recommended to positively attest to the results of laboratory findings.
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Affiliation(s)
- Imran Farooq
- Faculty of Dentistry, University of Toronto, Toronto, ON M5G 1G6, Canada
- Correspondence:
| | - Saqib Ali
- Department of Biomedical Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam 31441, Saudi Arabia;
| | - Samar Al-Saleh
- Prosthetic Dental Science, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia; (S.A.-S.); (E.M.A.); (T.A.); (F.V.)
| | - Eman M. AlHamdan
- Prosthetic Dental Science, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia; (S.A.-S.); (E.M.A.); (T.A.); (F.V.)
| | - Mohammad H. AlRefeai
- Operative Division, Department of Restorative Dentistry, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia;
| | - Tariq Abduljabbar
- Prosthetic Dental Science, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia; (S.A.-S.); (E.M.A.); (T.A.); (F.V.)
| | - Fahim Vohra
- Prosthetic Dental Science, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia; (S.A.-S.); (E.M.A.); (T.A.); (F.V.)
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Bastos NA, Bitencourt SB, Martins EA, De Souza GM. Review of nano-technology applications in resin-based restorative materials. J ESTHET RESTOR DENT 2020; 33:567-582. [PMID: 33368974 DOI: 10.1111/jerd.12699] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 12/09/2020] [Accepted: 12/14/2020] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Nanotechnology has progressed significantly and particles as small as 3 nm are being employed in resin-based restorative materials to improve clinical performance. The goal of this review is to report the progress of nanotechnology in Restorative Dentistry by reviewing the advantages, limitations, and applications of resin-based restorative materials with nanoparticles. MATERIALS AND METHODS A literature review was conducted using PubMed/Medline, Scopus and Embase databases. In vitro, in vivo and in situ research studies published in English between 1999 and 2020, and which focused on the analysis of resin-based restorative materials containing nanoparticles were included. RESULTS A total of 140 studies were included in this review. Studies reported the effect of incorporating different types of nanoparticles on adhesive systems or resin composites. Mechanical, physical, and anti-bacterial properties were described. The clinical performance of resin-based restorative materials with nanoparticles was also reported. CONCLUSIONS The high surface area of nanoparticles exponentially increases the bioactivity of materials using bioactive nanofillers. However, the tendency of nanoparticles to agglomerate, the chemical instability of the developed materials and the decline of rheological properties when high ratios of nanoparticles are employed are some of the obstacles to overcome in the near future. CLINICAL SIGNIFICANCE In spite of the recent advancements of nanotechnology in resin-based restorative materials, some challenges need to be overcome before new nano-based restorative materials are considered permanent solutions to clinical problems.
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Affiliation(s)
- Natalia Almeida Bastos
- Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil
| | - Sandro Basso Bitencourt
- Department of Dental Materials and Prosthodontics, Sao Paulo State University (UNESP), Araçatuba, Brazil
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Niobium silicate particles as bioactive fillers for composite resins. Dent Mater 2020; 36:1578-1585. [DOI: 10.1016/j.dental.2020.09.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 05/31/2020] [Accepted: 09/10/2020] [Indexed: 12/16/2022]
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Balbinot GS, Leitune VCB, Ogliari FA, Collares FM. Niobium silicate particles promote in vitro mineral deposition on dental adhesive resins. J Dent 2020; 101:103449. [PMID: 32777240 DOI: 10.1016/j.jdent.2020.103449] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 07/28/2020] [Accepted: 08/04/2020] [Indexed: 12/15/2022] Open
Abstract
OBJECTIVE This study aims to analyze the addition of niobium silicate particles to dental adhesive resins and evaluate its physicomechanical and biological properties. METHODS The SiNb particles were produced by the sol-gel route and presented a mean particle size of 2.1 μm and a specific surface area of 616,96m2/g. An experimental adhesive resin was formulated with 66 wt% Bisphenol A-Glycidyl Methacrylate and 33 wt% Hydroxyethyl methacrylate with diphenyl(2,4,6-trimethyl benzoyl)phosphine oxide as the photoinitiator. The SiNb particles were incorporated into the adhesive resins in 1 wt% (SiNb1%) and 2 wt% (SiNb2%) concentration. A control group (SiNb0%) without the addition of particles was used. The developed adhesives were evaluated by their polymerization kinetics, refractive index, softening in solvent, cytotoxicity, mineral deposition, ultimate tensile strength, and micro shear bond strength. RESULTS The refractive index range was increased by the addition of niobium silicate particles. No statistically significant difference was found between groups in the degree of conversion,.softening in solvent analysis, cytotoxicity and ultimate tensile strength. The deposition of minerals increased after immersion of specimens in SBF after 14 days on the SiNb2%. The SiNb2% group showed high micro shear bond strength values, reaching 33.87 MPa. CONCLUSION In the present study, the addition of 2 wt% of niobium silicate into dental adhesive resins promoted the mineral deposition with increased bond strength without affecting other material properties. CLINICAL SIGNIFICANCE Bioactive fillers must maintain the physical-chemical properties of dental adhesives, guaranteeing their clinical performance. Niobium silicate particles could promote the remineralization of dentin hard tissues without compromising the physico-mechanical properties on these materials.
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Affiliation(s)
- G S Balbinot
- Department of Dental Materials, School of Dentistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
| | - V C B Leitune
- Yller Biomaterials SA- Straumann Group, Pelotas, RS, Brazil.
| | - F A Ogliari
- Yller Biomaterials SA- Straumann Group, Pelotas, RS, Brazil.
| | - F M Collares
- Department of Dental Materials, School of Dentistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
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Balbinot EDCA, Pereira MFCC, Skupien JA, Balbinot CEA, da Rocha G, Vieira S. Analysis of transmittance and degree of conversion of composite resins. Microsc Res Tech 2019; 82:1953-1961. [PMID: 31411354 DOI: 10.1002/jemt.23364] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 07/09/2019] [Accepted: 08/01/2019] [Indexed: 11/05/2022]
Abstract
The objective of this study was to evaluate and correlate light transmittance (T), initial degree of conversion (IDC), and degree of conversion after 24 hr (DC24) for 22 composite resins (CR) for enamel and dentin use. The transmittance (n = 10) was measured with a spectrometer at a wavelength of 468.14 nm. The degree of conversion (DC; n = 5) was measured with Fourier Transform Near-Infrared Spectroscopy before polymerization, immediately after photoactivation, and 24 hr after photoactivation. Both sets of values are provided as percentages. ANOVA and Games-Howell (α = 5%) tests showed that Filtek Supreme Ultra gave the highest T values of all enamel CRs, while Esthet-X HD presented the lowest. Meanwhile, Venus diamond gave the highest values of all dentin CRs, while Esthet-X HD gave the lowest. For IDC and DC24, ANOVA showed differences between individual CRs and the two CR types (p < .0001). Despite the limitations of this study, it can be concluded that there was no correlation between T and either IDC or DC24 (p > .05); however, IDC and DC24 were strongly correlated (p < .05) by Pearson's correlation. That being said, as a higher DC reflects better mechanical properties, certain conclusions can be drawn about overall performance. The best IDC values were observed for the Opallis enamel resin and the Opallis and Premise dentin resins. Meanwhile, the best DC24 values were observed for the Opallis, Charisma, and Premise enamel resins and the Opallis and Premise dentin resins. Degree of conversion and light transmittance showed differences between composite resin types (enamel and dentin) and brands. It is important to know at the moment of composite choice taking into account mechanical and optical properties.
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Affiliation(s)
| | | | | | | | | | - Sergio Vieira
- School of Life Sciences, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil
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Par M, Gamulin O, Spanovic N, Bjelovucic R, Tarle Z. The effect of excitation laser power in Raman spectroscopic measurements of the degree of conversion of resin composites. Dent Mater 2019; 35:1227-1237. [PMID: 31155150 DOI: 10.1016/j.dental.2019.05.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 05/10/2019] [Accepted: 05/16/2019] [Indexed: 12/24/2022]
Abstract
OBJECTIVES To evaluate the effect of excitation laser power in Raman spectrometry by comparing the spectra and the degree of conversion (DC) values obtained using excitation powers between 300 and 1000mW. METHODS Five commercial and three experimental resin composites were light cured at 1200mW/cm2 for 10-20s from a commercial blue-violet LED dental curing unit. Raman spectra were collected from composite specimens within 9min after light-curing. The excitation laser (1064nm) was focused on the spot of 0.4mm in diameter. The following powers were used for specimen excitation (mW): 300, 400, 600, 800, and 1000. From Raman spectra, the DC values were calculated and compared among different laser powers. Also, vector-normalized Raman spectra collected using the lowest excitation power (300mW) were compared to those collected using the maximum excitation power (1000mW). RESULTS Varying the excitation laser power between 300 and 1000mW resulted in statistically significant differences in both the DC values and the intensity of particular spectral features. The effect of varying laser power on Raman spectra and obtained DC values was material-dependent. The DC values measured within an individual material using different laser powers varied between 3.2 and 7.2% (absolute DC difference). The spectral bands affected by variations in laser power were assigned to symmetric and asymmetric stretching of -CH2 (2900-3100cm-1), symmetric stretching of aliphatic CC (1640cm-1) and scissoring of C-H (1458cm-1). SIGNIFICANCE The DC can be artificially elevated through increasing excitation laser power. This effect should be considered in Raman spectroscopic evaluations of DC in specimens during ongoing post-cure polymerization.
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Affiliation(s)
- Matej Par
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Gunduliceva 5, Zagreb, Croatia.
| | - Ozren Gamulin
- Department of Physics and Biophysics, School of Medicine, University of Zagreb, Salata 3b, Zagreb, Croatia; Center of Excellence for Advanced Materials and Sensing Devices, Research Unit New Functional Materials, Bijenicka cesta 54, Zagreb, Croatia.
| | | | | | - Zrinka Tarle
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Gunduliceva 5, Zagreb, Croatia.
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Wavelength-dependent light transmittance in resin composites: practical implications for curing units with different emission spectra. Clin Oral Investig 2019; 23:4399-4409. [PMID: 30972599 DOI: 10.1007/s00784-019-02896-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 04/03/2019] [Indexed: 12/20/2022]
Abstract
OBJECTIVES To evaluate light transmittance as a function of wavelength for eight composite materials and compare the transmittance for blue light produced from two curing units with different emission spectra. MATERIALS AND METHODS Light transmittance through 2- and 4-mm-thick composite specimens was recorded in real time during 30 s of curing using a broad-spectrum (peaks at 405 and 450 nm) and a narrow-spectrum (peak at 441 nm) LED-curing unit. The spectral resolution of 0.25 nm and temporal resolution of 0.05 s resulted in a large amount of light transmittance data, which was averaged over particular spectral ranges, for the whole measurement period. Statistical analysis was performed using Welch ANOVA with Games-Howell post hoc test, t test, and Pearson correlation analysis. The level of significance was 0.05 and n = 5 specimens per experimental group were prepared. RESULTS Light transmittance varied as a function of wavelength and time, revealing significantly different patterns among the tested materials. Light transmittance for different parts of curing unit spectra increased in the following order of emission peaks (nm): 405 < 441 < 450. Of particular interest was the difference in transmittance between 441 and 450 nm, as these peaks are relevant for the photoactivation of camphorquinone-containing composites. A high variability in light transmittance among materials was identified, ranging from statistically similar values for both peaks up to a fourfold higher transmittance for the peak at 450 nm. CONCLUSION Each material showed a unique pattern of wavelength-dependent light transmittance, leading to highly material-dependent differences in blue light transmittance between two curing units. CLINICAL RELEVANCE Minor differences in blue light emission of contemporary narrow-peak curing units may have a significant effect on the amount of light which reaches the composite layer bottom.
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Par M, Spanovic N, Bjelovucic R, Marovic D, Schmalz G, Gamulin O, Tarle Z. Long-term water sorption and solubility of experimental bioactive composites based on amorphous calcium phosphate and bioactive glass. Dent Mater J 2019; 38:555-564. [PMID: 30713282 DOI: 10.4012/dmj.2018-145] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The aim of this study was to evaluate water sorption and solubility of two series of experimental composites containing amorphous calcium phosphate (ACP) or bioactive glass (BG). Water sorption and solubility were measured for up to 287 days. The surface precipitation of calcium phosphates was evaluated by scanning electron microscopy. The ACP-series showed higher water sorption (223-568 µg/mm3) than the BG-series (40-232 µg/mm3). In contrast, the ACP-series had generally lower solubility (37-106 µg/mm3) than the BG-series (1-506 µg/mm3). The constant specimen mass for the ACP-series was attained after 14 days of water immersion, while the mass decrease due to long-term solubility in the BG-series lasted beyond 287 days. Calcium phosphates precipitated in composites with the BG filler loading of 10 wt% or more, as well as in all of the ACP-containing composites. The experimental composite series showed water sorption and solubility considerably higher than commercial materials.
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Affiliation(s)
- Matej Par
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb
| | | | | | - Danijela Marovic
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb
| | - Gottfried Schmalz
- Department of Operative Dentistry and Periodontology, University Hospital Regensburg, University of Regensburg.,Department of Periodontology, Dental School University of Bern
| | - Ozren Gamulin
- Department of Physics and Biophysics, School of Medicine, University of Zagreb.,Center of Excellence for Advanced Materials and Sensing Devices, Research Unit New Functional Materials
| | - Zrinka Tarle
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb
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Par M, Repusic I, Skenderovic H, Sever EK, Marovic D, Tarle Z. Real-time Light Transmittance Monitoring for Determining Polymerization Completeness of Conventional and Bulk Fill Dental Composites. Oper Dent 2018; 43:E19-E31. [PMID: 29284096 DOI: 10.2341/17-041-l] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVES To monitor the real-time changes in light transmittance during composite curing and to use transmittance data to determine the curing times required for a complete polymerization. METHODS Three conventional and three bulk fill composites were cured with two light-emitting diode curing units at layer thicknesses of 2 mm and 4 mm. The real-time light transmittance data were collected by a UV-Vis spectrometer in the wavelength range of 350-550 nm, plotted against time (t) and fitted to an exponential function f(t), whose first derivative ΔT(t) = df(t)/dt represented the rate of transmittance change. As the changing transmittance reflects structural changes that occur during polymerization, ΔT(t) > 0 was considered to indicate an ongoing polymerization, whereas ΔT(t) values approaching zero suggested a complete polymerization. This principle was used to determine times required for a complete polymerization (tcomplete) for each material/thickness/curing unit combination. RESULTS Light transmittance was significantly influenced by the material type, sample thickness, and curing unit, amounting to 2.9%-27.0% for the bulk fill and 0.7%-16.7% for the conventional composites. The values of tcomplete amounted to 15.3-23.3 seconds for the bulk fill composites at 2 mm, 20.2-33.3 seconds for the conventional composites at 2 mm, 26.9-42.1 seconds for the bulk fill composites at 4 mm, and 40.1-59.8 seconds for the conventional composites at 4 mm. Additionally, an exponential relationship was discovered between the light transmittance and tcomplete. CONCLUSIONS Some of the tcomplete values considerably exceeded the curing times recommended by the manufacturers.
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Par M, Tarle Z, Hickel R, Ilie N. Real-time curing characteristics of experimental resin composites containing amorphous calcium phosphate. Eur J Oral Sci 2018; 126:426-432. [PMID: 30113752 DOI: 10.1111/eos.12566] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/16/2018] [Indexed: 11/28/2022]
Abstract
The real-time polymerization of light-curable experimental resin composites filled with amorphous calcium phosphate (ACP) was monitored. Experimental composites were based on a 2,2-bis[4-(2-ethoxy-3-methacryloyloxy propoxy)phenyl]propane (Bis-EMA)/triethyleneglycol dimethacrylate (TEGDMA)/2-hydroxyethyl methacrylate (HEMA) resin photoactivated by a camphorquinone/tertiary amine system. Four ACP composites were prepared, containing 40 wt% ACP and 0/10 wt% reinforcing fillers (barium glass and silica). Additionally, two control composites were prepared which contained only reinforcing fillers (40-50 wt%). The degree of conversion (DC) was monitored in real time using a Fourier-transform infrared (FTIR) spectrometer with an attenuated total reflectance accessory. During the light curing (1,219 mW cm-2 ) for either 20 or 40 s, infrared spectra were collected from the bottom of 2-mm-thick composite specimens at the rate of two spectra per second over 5 min. When cured for 40 s, the ACP composites attained a high DC (89.1%-92.4%), while the DC of control composites was significantly lower (53.5%-68.4%). All materials showed a lower DC for the shorter curing time (20 s) and various extents of 5-min postcure polymerization: 12.9%-21.5% for the ACP composites and 2.7%-5.2% for the control composites. The control composites reached the maximum reaction rate much earlier (4.1-4.3 s) and at lower DC (9.9%-10.4%) than did the ACP composites (17.4-22.0 s and 43.5%-49.3%, respectively).
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Affiliation(s)
- Matej Par
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Zagreb, Croatia
| | - Zrinka Tarle
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Zagreb, Croatia
| | - Reinhard Hickel
- Department of Restorative Dentistry, Periodontology and Pedodontics, Ludwig-Maximilians-University of Munich, Munich, Germany
| | - Nicoleta Ilie
- Department of Restorative Dentistry, Periodontology and Pedodontics, Ludwig-Maximilians-University of Munich, Munich, Germany
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Par M, Tarle Z, Hickel R, Ilie N. Polymerization kinetics of experimental bioactive composites containing bioactive glass. J Dent 2018; 76:83-88. [PMID: 29935997 DOI: 10.1016/j.jdent.2018.06.012] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 05/14/2018] [Accepted: 06/20/2018] [Indexed: 10/28/2022] Open
Abstract
OBJECTIVES To investigate the polymerization kinetics and the degree of conversion (DC) of experimental resin composites with varying amount of bioactive glass 45S5 (BG). METHODS Experimental resin composites based on a photo-curable Bis-GMA/TEGDMA resin system were prepared. The composite series contained 0, 5, 10, 20, and 40 wt% of BG and reinforcing fillers up to the total filler amount of 70 wt%. Composite specimens were light cured with 1219 mW/cm2 for 20 or 40 s and their DC was monitored during 5 min at the data collection rate of 2 s-1 using attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). RESULTS The 5-min DC values for experimental composites were in the range of 42.4-55.9% and 47.3-57.9% for curing times of 20 and 40 s, respectively. The differences in the 5-min DC between curing times of 20 s or 40 s became more pronounced in materials with higher BG amount. Within both curing times, a decreasing trend of the 5-min DC values was observed with the increasing percentage of BG fillers. The maximum polymerization rate also decreased consistently with the increasing BG amount. CONCLUSIONS Unsilanized BG fillers showed a dose-dependent inhibitory effect on polymerization rate and the DC. Extending the curing time from 20 to 40 s showed a limited potential to improve the DC of composites with higher BG amount. SIGNIFICANCE The observed inhibitory effect of BG fillers on the polymerization of resin composites may have a negative influence on mechanical properties and biocompatibility.
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Affiliation(s)
- Matej Par
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Gunduliceva 5, Zagreb, Croatia.
| | - Zrinka Tarle
- Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Gunduliceva 5, Zagreb, Croatia.
| | - Reinhard Hickel
- Department of Restorative Dentistry, Periodontology and Pedodontics, Ludwig-Maximilians-University of Munich, Goethestr. 70, Munich, Germany.
| | - Nicoleta Ilie
- Department of Restorative Dentistry, Periodontology and Pedodontics, Ludwig-Maximilians-University of Munich, Goethestr. 70, Munich, Germany.
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Curing potential of experimental resin composites with systematically varying amount of bioactive glass: Degree of conversion, light transmittance and depth of cure. J Dent 2018; 75:113-120. [PMID: 29908899 DOI: 10.1016/j.jdent.2018.06.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 05/11/2018] [Accepted: 06/14/2018] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVES The aim of this work was to investigate the curing potential of an experimental resin composite series with the systematically varying amount of bioactive glass 45S5 by evaluating the degree of conversion, light transmittance and depth of cure. METHODS Resin composites based on a Bis-GMA/TEGDMA resin with a total filler load of 70 wt% and a variable amount of bioactive glass (0-40 wt%) were prepared. The photoinitiator system was camphorquinone and ethyl-4-(dimethylamino) benzoate. The degree of conversion and light transmittance were measured by Raman spectroscopy and UV-vis spectroscopy, respectively. The depth of cure was evaluated according to the classical ISO 4049 test. RESULTS The initial introduction of bioactive glass into the experimental series diminished the light transmittance while the further increase in the bioactive glass amount up to 40 wt% caused minor variations with no clear trend. The curing potential of the experimental composites was similar to or better than that of commercial resin composites. However, unsilanized bioactive glass fillers demonstrated the tendency to diminish both the maximum attainable conversion and the curing efficiency at depth. CONCLUSIONS Experimental composite materials containing bioactive glass showed a clinically acceptable degree of conversion and depth of cure. The degree of conversion and depth of cure were diminished by bioactive glass fillers in a dose-dependent manner, although light transmittance was similar among all of the experimental composites containing 5-40 wt% of bioactive glass. CLINICAL SIGNIFICANCE Reduced curing potential caused by the bioactive glass has possible consequences on mechanical properties and biocompatibility.
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Marović D, Šariri K, Demoli N, Ristić M, Hiller KA, Škrtić D, Rosentritt M, Schmalz G, Tarle Z. Remineralizing amorphous calcium phosphate based composite resins: the influence of inert fillers on monomer conversion, polymerization shrinkage, and microhardness. Croat Med J 2017; 57:465-473. [PMID: 27815937 PMCID: PMC5141456 DOI: 10.3325/cmj.2016.57.465] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Aim To determine if the addition of inert fillers to a bioactive dental restorative composite material affects its degree of conversion (DC), polymerization shrinkage (PS), and microhardness (HV). Methods Three amorphous calcium phosphate (ACP)-based composite resins: without added fillers (0-ACP), with 10% of barium-glass fillers (Ba-ACP), and with 10% of silica fillers (Si-ACP), as well as commercial control (Ceram•X, Dentsply DeTrey) were tested in laboratory conditions. The amount of ACP (40%) and the composition of the resin mixture (based on ethoxylated bisphenol A dimethacrylate) was the same for all ACP materials. Fourier transform infrared spectroscopy was used to determine the DC (n = 40), 20 min and 72 h after polymerization. Linear PS and Vickers microhardness (n = 40) were also evaluated. The results were analyzed by paired samples t test, ANOVA, and one-way repeated measures ANOVA with Student-Newman-Keuls or Tukey’s post-hoc test (P = 0.05). Results The addition of barium fillers significantly increased the DC (20 min) (75.84 ± 0.62%) in comparison to 0-ACP (73.92 ± 3.08%), but the addition of silica fillers lowered the DC (71.00 ± 0.57%). Ceram•X had the lowest DC (54.93 ± 1.00%) and linear PS (1.01 ± 0.24%) but the highest HV (20.73 ± 2.09). PS was significantly reduced (P < 0.010) in both Ba-ACP (1.13 ± 0.25%) and Si-ACP (1.17 ± 0.19%) compared to 0-ACP (1.43 ± 0.21%). HV was significantly higher in Si-ACP (12.82 ± 1.30) than in 0-ACP (10.54 ± 0.86) and Ba-ACP (10.75 ± 0.62) (P < 0.010). Conclusion Incorporation of inert fillers to bioactive remineralizing composites enhanced their physical-mechanical performance in laboratory conditions. Both added fillers reduced the PS while maintaining high levels of the DC. Silica fillers additionally moderately improved the HV of ACP composites.
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Affiliation(s)
- Danijela Marović
- Danijela Marović, Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Gundulićeva 5, 10 000 Zagreb, Croatia,
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