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Ansarifard E, Taghva M, Mosaddad SA, Akhlaghian M. The impact of various substrates, ceramic shades, and brands on the ultimate color and masking capacity of highly translucent monolithic zirconia: an in vitro study. Odontology 2024:10.1007/s10266-024-00996-0. [PMID: 39222097 DOI: 10.1007/s10266-024-00996-0] [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: 05/01/2024] [Accepted: 08/15/2024] [Indexed: 09/04/2024]
Abstract
This study aimed to examine the impact of substrates, ceramic shades, and brands on the color and masking ability of highly translucent monolithic zirconia (HTMZ) using CIELab and CIEΔE2000 metrics. A total of 156 1-mm thick HTMZ disks in shades A1, A2, and A3 were produced using Dental Direkt and Kerox zirconia brands. Four 3-mm thick substrates (nickel-chromium alloy, non-precious gold alloy (NPG), zirconia shade A2, and resin composite shade A2) were prepared. HTMZ disks were overlaid on these substrates, and color measurements were taken with a spectrophotometer. Color differences (ΔE) were analyzed using CIELab and CIEΔE2000 formulas. The influence of brand, shade, substrate, and their interactions on ΔE values was assessed with a General Linear Model (GLM) and LSD pairwise comparison test. Spearman's correlation test examined the relationship between CIELab and CIEΔE2000 values. Results indicated that ΔEab was significantly influenced by substrate type and shade, while ΔE2000 was also affected by the ceramic brand. Mean color differences across ceramic-substrate groups were within clinically acceptable and perceptible ranges (clinically perceptible: ∆Eab ≥ 1.3 and ∆E2000 ≥ 0.8; clinically acceptable: 0.8 < ∆E2000 ≤ 1.8 and 1.3 < ∆Eab ≤ 2.7), except for NPG, which had ΔE values exceeding the perceptible range (ΔE2000: 1.1 ± 0.11 to 1.8 ± 0.31; ΔEab: 1.61 ± 0.15 to 2.16 ± 0.36). A significant correlation (r = 0.974, P < 0.001) was found between ΔEab and ΔE2000. Various ceramic brands and shades led to notable ΔE variations, yet average color differences within all ceramic-substrate groups remained clinically acceptable. Both ΔEab and ΔE2000 were reliable methods with a strong correlation for measuring color differences.
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Affiliation(s)
- Elham Ansarifard
- Department of Prosthodontics, Biomaterials Research Center, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Masumeh Taghva
- Department of Prosthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Seyed Ali Mosaddad
- Department of Prosthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
- Department of Research Analytics, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, India.
- Student Research Committee, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
- Department of Conservative Dentistry and Bucofacial Prostheses, Faculty of Odontology, University Complutense of Madrid, Madrid, Spain.
| | - Marzieh Akhlaghian
- Department of Prosthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
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Strazzi-Sahyon HB, Hadis MA, Dos Santos PH, Palin WM. The effect of photoinitiator type and filler load on physicochemical and mechanical properties of experimental light-cured resin cements through lithium disilicate ceramics of different shades and thicknesses. Dent Mater 2024; 40:1452-1463. [PMID: 38945741 DOI: 10.1016/j.dental.2024.06.020] [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: 09/23/2023] [Revised: 06/13/2024] [Accepted: 06/14/2024] [Indexed: 07/02/2024]
Abstract
OBJECTIVE This study investigated the influence of photoinitiator types on degree of conversion (DC), rate of polymerization (RP), flexural strength (FS), flexural modulus (FM), and light transmittance (LT) of filled and unfilled light-curable resin cements through different thicknesses and shades of lithium disilicate ceramics. METHODS Lithium disilicate ceramic discs (IPS Emax Press, background [0.0], 0.5, 1.0, 2.0, 3.0, and 4.0 mm, shades A1 and BL3) were prepared. Experimental resin-based cements [TEGDMA/BisGMA (50/50 mass%)] were prepared using either camphorquinone (CQ)/amine (0.44/1.85 mol%) or TPO (0.44 mol%)], and a micro and nanofiller loads of nil (unfilled); 40/10 mass%; and 50/10 mass%). Resin cements (0.2 mm thick) were placed on the lower surface of the ceramic specimens and light-activated for 30 s from the upper surface using a Bluephase Style curing light (exitance at tip: 1236 mW/cm2 ± 1.20). LT and distribution of irradiance through the ceramics were measured using a UV-vis spectrometer and a beam profile camera, respectively (n = 3). The DC and RP were measured in real-time using mid infrared spectroscopy in attenuated total reflectance (ATR) mode (n = 3). FS and FM were measured using a universal testing machine (n = 5). Statistical analyses were performed on LT, DC, RP, FS, and FM data using a general linear model, and supplementary ANOVA and post hoc Tukey multiple comparison test were also performed (α = .05). RESULTS Thicknesses, shades, photoinitiator type, and fillers load significantly influenced the optical and mechanical characteristics of the resin-based materials (p < 0.05). The BL3 shade ceramic provided higher values of DC, RP, FS, FM, and LT compared with the A1 shade (p < 0.05). Increasing ceramic thickness decreased the properties of the resin-based materials (p < 0.05). Generally, TPO improved mechanical properties of the resin cement compared with CQ (p < 0.05). SIGNIFICANCE The luting process of indirect restorations may be improved by using high molar absorptivity, more reactive, and more efficient photoinitiators such as TPO, as opposed to conventional CQ. The use of such initiator may allow the placement of thicker and more opaque indirect restorations.
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Affiliation(s)
- Henrico Badaoui Strazzi-Sahyon
- Department of Dental Materials and Prosthodontics, Araçatuba School of Dentistry, São Paulo State University - UNESP, Araçatuba, SP, Brazil; Department of Prosthodontics and Periodontology, Bauru School of Dentistry, University of São Paulo, USP, Bauru, SP, Brazil; Biomaterials Unit, School of Dentistry, College of Medical and Dental Sciences, University of Birmingham, Birmingham B4 6NN, UK.
| | - Mohammed A Hadis
- Biomaterials Unit, School of Dentistry, College of Medical and Dental Sciences, University of Birmingham, Birmingham B4 6NN, UK
| | - Paulo Henrique Dos Santos
- Department of Dental Materials and Prosthodontics, Araçatuba School of Dentistry, São Paulo State University - UNESP, Araçatuba, SP, Brazil; Dental Research Institute - Restorative Dentistry, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada
| | - William M Palin
- Biomaterials Unit, School of Dentistry, College of Medical and Dental Sciences, University of Birmingham, Birmingham B4 6NN, UK
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Chou YC, Chuang SF, Lin JC, Li CL, Liu BY, Lee CL. Application of near-infrared-to-blue upconversion luminescence for the polymerization of resin cements through zirconia discs. Dent Mater 2024; 40:1208-1215. [PMID: 38851964 DOI: 10.1016/j.dental.2024.06.005] [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: 01/18/2024] [Revised: 06/02/2024] [Accepted: 06/03/2024] [Indexed: 06/10/2024]
Abstract
OBJECTIVES To investigate a near-infrared-to-blue luminescence upconversion curing method for polymerizing resin cements under zirconia discs. METHODS Lava zirconia discs of different thicknesses (0.5-2.0 mm) were manufactured. First, the transmittances of the NIR and two blue lights (BLs) (LED and halogen lights) through these discs were measured. Second, NaYF4:Yb3+/Tm3+ upconversion phosphor (UP) powder was milled into 0.5-μm particle sizes. A light-curable resin cement VariolinkII base was chosen as the control (UP0), and an experimental cement (UP5) was prepared by adding 5 % UPs. These two cements were examined using multiphoton excitation microscopy for particle distribution. UP5 and UP0 were polymerized with or without zirconia shielding then subjected to a microhardness test. A multifold analysis was performed to examine the effects of zirconia thickness, curing protocols (pure BL or combined BL and NIR curing), and cement type. RESULTS The transmittance of NIR was superior to that of BL through zirconia discs of all thicknesses. UP particles were homogeneously distributed in UP5 and emitted blue luminescence under 980-nm NIR excitation. UP5 showed higher microhardness values than UP0 under any curing protocol or zirconia shielding condition. The combination of 20-s BL and 40-s NIR curing yielded the highest microhardness in uncovered UP5. However, combining 40-s BL and 20-s NIR curing surpassed the other groups when the zirconia discs were thicker than 0.5 mm. SIGNIFICANCE NIR exhibits higher transmission through zirconia than BL. UP particles work as strengthen fillers and photosensitizers in cements. NIR upconversion curing could be a new strategy for polymerizing resin cements under thick zirconia restorations.
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Affiliation(s)
- Yu-Cheng Chou
- School of Dentistry and Institute of Oral Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Stomatology, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Shu-Fen Chuang
- School of Dentistry and Institute of Oral Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Stomatology, National Cheng Kung University Hospital, Tainan, Taiwan.
| | - Jui-Che Lin
- Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan
| | - Chia-Ling Li
- School of Dentistry and Institute of Oral Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Bang-Yan Liu
- School of Dentistry and Institute of Oral Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Chung-Lin Lee
- Department of Stomatology, National Cheng Kung University Hospital, Tainan, Taiwan
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Yang F, Zhang L, Yang M, Chen J, Xing W. The effect of deviations in sintering temperature on the translucency and color of multi-layered zirconia. BMC Oral Health 2024; 24:471. [PMID: 38637799 PMCID: PMC11027308 DOI: 10.1186/s12903-024-04243-4] [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: 01/16/2024] [Accepted: 04/09/2024] [Indexed: 04/20/2024] Open
Abstract
OBJECT This study aimed to investigate the changes in the translucency and color of four different multi-layered zirconia materials when the sintering temperature were inaccurate. MATERIALS AND METHODS Two hundred zirconia samples (11 × 11 × 1.0 mm) of four multi-layered zirconia, Upcera TT-GT (UG), Upcera TT-ML (UM), Cercon xt ML (CX), and Lava Esthetic (LE), were divided into five subgroups according to the sintering temperature: L1 (5% lower temperature), L2 (2.5% lower temperature), R (recommended sintering temperature), H2 (2.5% higher temperature), H1 (5% higher temperature). After sintering, color coordinates were measured. Then the translucency parameter (TP) values, and the color differences (between the inaccurate sintering temperature and the recommended temperature) of each zirconia specimen were calculated. Statistical analysis was performed by using three-way ANOVA tests, the one-way ANOVA, and Tukey's post hoc test. RESULTS Three-way ANOVA results showed that material type, sintering temperature, specimen section, and their interactions significantly influenced the TP values (except for the interactions of specimen section and sintering temperature) (P < .05). TP values of zirconia specimens were significantly different in the inaccurate sintering temperatures (P < .05), except for the cervical and body sections of UG group (P > .05). Compared with recommended sintering temperature, higher sintering temperature caused higher TP values for CX, but lower for LE. Three-way ANOVA results showed that material type, sintering temperature, and their interactions significantly influenced the ∆E00 values (P < .05). There were no significant differences in ∆E00 values of UM and CX groups at different inaccurate sintering temperatures, and were clinical imperception (except for UM-L1) (∆E00 < 1.25). ∆E00 values of all zirconia specimens showed clinically acceptable (∆E00 < 2.23). CONCLUSION The deviations in sintering temperature significantly influenced the translucency and color of tested multi-layered zirconia. The trends of translucency in the multi-layered zirconia depended on material type and the color changes of all zirconia materials were clinically acceptable at inaccurate sintering temperatures.
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Affiliation(s)
- Fan Yang
- Graduate School of Dalian Medical University, Dalian, China
| | - Luyao Zhang
- Graduate School of Dalian Medical University, Dalian, China
| | - Minghui Yang
- Dental Technology Center, Dalian Stomatological Hospital, Dalian, China
| | - Jianfeng Chen
- Department of Stomatology, The First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Wenzhong Xing
- Department of Prosthodontics, Dalian Stomatological Hospital, Dalian, Liaoning, 116021, PR China.
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Lee H, Young Kim RJ, Seo DG. Shear bond strength of dual-cured resin cements on zirconia: The light-blocking effect of a zirconia crown. J Dent Sci 2024; 19:162-168. [PMID: 38303887 PMCID: PMC10829558 DOI: 10.1016/j.jds.2023.05.011] [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: 03/27/2023] [Revised: 05/08/2023] [Indexed: 02/03/2024] Open
Abstract
Abstract Background/purpose The presence of restorative material between resin cement and the light-curing unit can reduce light transmission. This study aimed to evaluate the effect of the light-blocking effect of zirconia crown on shear bond strength (SBS) between three dual-cured resin cements and the zirconia surface. Materials and methods Sixty zirconia specimens were prepared and divided into three groups according to the type of resin cement [RXU (RelyX Ultimate); SC2 (SmartCem2); MEC (Maxcem Elite Chroma)]. Each group was further divided into two subgroups, with or without a 1-mm-thick zirconia crown (n = 10). The specimens were light-cured from five different directions for 20 s each. All specimens were thermocycled 5000 times and subjected to SBS testing, followed by scanning electron microscope examination. Results The presence of a 1-mm-thick zirconia crown had no significant effect on the SBS in all resin cements. However, the SBS was significantly affected by type of resin cement. RXU showed the highest SBS (8.35 MPa with crown; 8.57 MPa without crown), followed by SC2 (5.48 MPa with crown; 5.57 without crown) and then MEC (3.37 MPa with crown; 4.04 MPa without crown. Fractured surfaces exhibited varying degrees of mixed failure patterns. Conclusion A 1-mm-thick zirconia crown material between the light source and the dual-cured resin cement did not significantly influence the SBS of the resin cements on the zirconia substrates. RXU exhibited the highest SBS regardless of zirconia crown coverage. With sufficient light-curing, dual-cured resin cements can be a good choice for zirconia crown cementation.
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Affiliation(s)
- Hyesoo Lee
- Seoul Kwon Dental Clinic, Seoul, South Korea
| | - Ryan Jin Young Kim
- Department of Dental Sciences, Dental Research Institute, Seoul National University School of Dentistry, Seoul, South Korea
| | - Deog-Gyu Seo
- Department of Conservative Dentistry, Dental Research Institute, Seoul National University School of Dentistry, Seoul, South Korea
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Park SH, Huh YH, Park CJ, Cho LR, Ko KH. Degree of conversion of light-polymerized composite resin in implant prosthesis screw access opening. J Prosthodont 2023; 32:829-837. [PMID: 36575827 DOI: 10.1111/jopr.13637] [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: 07/07/2022] [Revised: 12/14/2022] [Accepted: 12/16/2022] [Indexed: 12/29/2022] Open
Abstract
PURPOSE The mechanical and physical properties of implant screw access opening deteriorate if composite resin is not polymerized properly. Therefore, this study aimed to analyze the effect of using composite resin in implant access opening on the degree of conversion (DC). MATERIALS AND METHODS Two prosthetic materials (Co-Cr and zirconia), two types of composite resin (low and high viscosity), two light-cured resin depths (2 and 3 mm), and two polymerization methods (max-mode 10 s and mid-mode 20 s: 16 and 22 J/cm2 , respectively) were considered (n = 192). The DC of the polymerized composite resin was measured through Fourier-transform infrared spectroscopy. The top and bottom surfaces of the polymerized composite resin body were observed through scanning electron microscopy. Multiple linear regression analysis and analysis of variance were used to identify significant differences in DC (α = 0.05). RESULTS The DC was lower when the low-viscosity composite resin (β = -0.431), light-polymerized resin depth of 2 mm (β = -0.430), zirconia prosthesis (β = -0.191), and mid-mode polymerization method (β = -0.164) were used. The resin type, depth of resin to be light-cured, prosthesis material, and polymerization method had an effect on the DC. CONCLUSIONS Low-viscosity composite resin should be polymerized at a low irradiance and long polymerization time (such that the light-cured resin depth does not exceed 2 mm) to ensure proper composite resin polymerization in implant screw access opening.
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Affiliation(s)
- Se-Hyun Park
- College of Dentistry, Gangneung-Wonju National University, Gangneung, Republic of Korea
| | - Yoon-Hyuk Huh
- Department of Prosthodontics and Research Institute of Oral Science, College of Dentistry, Gangneung-Wonju National University, Gangneung, Republic of Korea
| | - Chan-Jin Park
- Department of Prosthodontics and Research Institute of Oral Science, College of Dentistry, Gangneung-Wonju National University, Gangneung, Republic of Korea
| | - Lee-Ra Cho
- Department of Prosthodontics and Research Institute of Oral Science, College of Dentistry, Gangneung-Wonju National University, Gangneung, Republic of Korea
| | - Kyung-Ho Ko
- Department of Prosthodontics and Research Institute of Oral Science, College of Dentistry, Gangneung-Wonju National University, Gangneung, Republic of Korea
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Queiroz ME, Maluly-Proni AT, Tsutsumi MSC, Dallazen E, de Castro-Hoshino LV, de Souza M, Baesso ML, Dos Santos PH. Influence of thickness and degree of opacity of lithium disilicate on the degree of conversion and bond strength of resin cements. J Mech Behav Biomed Mater 2023; 143:105934. [PMID: 37257313 DOI: 10.1016/j.jmbbm.2023.105934] [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: 03/30/2023] [Revised: 05/21/2023] [Accepted: 05/21/2023] [Indexed: 06/02/2023]
Abstract
The aim of this study was to evaluate the influence of various opacities and thicknesses of lithium disilicate on the degree of conversion (DC) of two resin cements and on their bond strength (BS) to the ceramic. Two hundred and forty ceramic samples of lithium disilicate with high translucency (HT), low translucency (LT), and medium opacity (MO) were obtained from IPS e. max CAD in five different thicknesses. Light-cured and dual-cured resin cements were used for DC (n = 9) and BS (n = 8). Cement samples were light-cured under ceramic samples and analyzed using a Raman confocal spectrometer to determine the DC. For BS, resin cement cylinders were fabricated using ceramic samples which were thsen subjected to a microshear bond strength test. The mean values were provided for statistical analysis. The increase in thickness resulted in a decrease in DC for both cements under all experimental conditions, but only affected the BS of the light-cured cement for the MO ceramic. Comparing the opacities, the most translucent ceramics with particular thicknesses exhibited higher DC values than the less translucent ceramics. The LT and MO ceramics with certain thicknesses exhibited the highest BS values than the HT. The dual-cured cement generally showed highest values in both analyses than the light-cured cement. A thicker and more opaque ceramic material can reduce the DC of the cement. The BS decreases with the increasing thickness of the more-opaque ceramics.
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Affiliation(s)
- Mariana Elias Queiroz
- Department of Dental Materials and Prosthodontics, Araçatuba School of Dentistry, São Paulo State University - UNESP, Araçatuba, SP, Brazil
| | - Ana Teresa Maluly-Proni
- Department of Preventive and Restorative Dentistry, Araçatuba School of Dentistry, São Paulo State University - UNESP, Araçatuba, SP, Brazil
| | - Mariana Sati Cantalejo Tsutsumi
- Department of Preventive and Restorative Dentistry, Araçatuba School of Dentistry, São Paulo State University - UNESP, Araçatuba, SP, Brazil
| | - Eduardo Dallazen
- Department of Diagnosis and Surgery, Araçatuba School of Dentistry, São Paulo State University - UNESP, Araçatuba, SP, Brazil
| | | | - Monique de Souza
- Department of Physics, State University of Maringá - UEM, Maringá, PR, Brazil
| | | | - Paulo Henrique Dos Santos
- Department of Dental Materials and Prosthodontics, Araçatuba School of Dentistry, São Paulo State University - UNESP, Araçatuba, SP, Brazil; Dental Research Institute, University of Toronto, Faculty of Dentistry - UofT, Toronto, ON, Canada.
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Elraggal A, Aboushelib M, Abdel Raheem IM, Afifi RR. Effect of surface treatments on biaxial flexural strength, fatigue resistance, and fracture toughness of high versus low translucency zirconia. BMC Oral Health 2022; 22:412. [PMID: 36123676 PMCID: PMC9487058 DOI: 10.1186/s12903-022-02431-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Accepted: 09/05/2022] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Mechanical surface treatments can deteriorate the mechanical properties of zirconia. This study evaluated and compared the biaxial flexural strength, fracture toughness, and fatigue resistance of high translucency (HT) to low translucency (LT) zirconia after various mechanical surface treatments. METHODS Four hundred eighty zirconia discs were prepared by milling and sintering two HT (Katana and BruxZir) and LT (Cercon and Lava) zirconia blocks at targeted dimensions of 12 mm diameter × 1.2 mm thickness. Sintered zirconia discs received one of the following surface treatments: low-pressure airborne particle abrasion (APA) using 50 µm alumina particles, grinding using 400 grit silicon carbide paper, while as-sintered specimens served as control. Internal structure and surface roughness were evaluated by scanning electron microscope (SEM) and a non-contact laser profilometer, respectively. Half of the discs were tested for initial biaxial flexural strength, while the rest was subjected to 106 cyclic fatigue loadings, followed by measuring the residual biaxial flexural strength. Fractured surfaces were examined for critical size defects (c) using SEM to calculate the fracture toughness (KIC). The effect of surface treatments, zirconia type, and cyclic fatigue on the biaxial flexural strength was statistically analyzed using three-way analysis of variance (ANOVA) and Tukey HSD post hoc tests (α = 0.05). Weibull analysis was done to evaluate the reliability of the flexural strength for different materials. RESULTS The initial biaxial flexural strength of LT zirconia was significantly higher (p < 0.001) than that of HT zirconia in all groups. While low APA significantly increased the biaxial flexural strength of LT zirconia, no significant change was observed for HT zirconia except for Katana. Surface grinding and cyclic fatigue significantly reduced the flexural strength of all groups. High translucency zirconia reported higher fracture toughness, yet with lower Weibull moduli, compared to LT zirconia. CONCLUSION LT zirconia has higher biaxial flexural strength, yet with lower fracture toughness and fatigue resistance, compared to HT zirconia. Low-pressure APA has significantly increased the biaxial flexural strength in all zirconia groups except BruxZir. Grinding was deteriorating to biaxial flexural strength and fracture toughness in all zirconia types. Cyclic fatigue has significantly decreased the biaxial flexural strength and reliability of HT and LT zirconia.
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Affiliation(s)
- Alaaeldin Elraggal
- Conservative Dentistry Department, Faculty of Dentistry, Alexandria University, Alexandria, Egypt.
| | - Moustafa Aboushelib
- grid.7155.60000 0001 2260 6941Dental Biomaterials Department, Faculty of Dentistry, Alexandria University, Alexandria, Egypt
| | - Islam M. Abdel Raheem
- grid.7155.60000 0001 2260 6941Conservative Dentistry Department, Faculty of Dentistry, Alexandria University, Alexandria, Egypt
| | - Rania R. Afifi
- grid.7155.60000 0001 2260 6941Conservative Dentistry Department, Faculty of Dentistry, Alexandria University, Alexandria, Egypt
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Alkurt M, Duymus ZY, Yildiz Ş. How home bleaching agents affect the color and translucency of CAD/CAM monolithic zirconia materials. Dent Mater J 2022; 41:511-519. [PMID: 35584933 DOI: 10.4012/dmj.2021-002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
To assess the effect of 10% carbamide peroxide (CP) and 6% hydrogen peroxide (HP) home bleaching agents on the translucency and color of monolithic zirconia. Ninety disc specimens were fabricated (diameter, 10 mm) from multi-layered (ML), ultra translucent multi-layered (UTML), and super translucent multi-layered (STML) zirconia blocks at three thicknesses (0.4,1,1.5 mm) (n=5). The samples were divided into two subgroups, which were treated with 6% HP (45 min per day) or 10% CP (8 h per day) for 14 days. The color of specimens was measured before bleaching (T0) and after bleaching on the third (T3), seventh (T7), and 14th (T14) day. Color (∆E) and translucency (TP) changes were calculated. The thickness varieties used in the samples and the bleaching agent types used created statistically significant differences only in TP and ∆E00, respectively (p<0.05). Bleaching agents can affect TP and ∆E. Patients who have zirconia restorations should be careful when using home bleaching agents.
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Affiliation(s)
- Murat Alkurt
- Department of Prosthodontics, Faculty of Dentistry, Recep Tayyip Erdogan University
| | - Zeynep Yesil Duymus
- Department of Prosthodontics, Faculty of Dentistry, Recep Tayyip Erdogan University.,Department of Prosthodontics, Faculty of Dentistry, Atatürk University
| | - Şeyma Yildiz
- Department of Prosthodontics, Faculty of Dentistry, Recep Tayyip Erdogan University
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Go YR, Kim KM, Park SH. Influence of inhomogeneity of the polymerization light beam on the microhardness of resin cement under a CAD-CAM block. J Prosthet Dent 2022; 127:802.e1-802.e10. [PMID: 35272842 DOI: 10.1016/j.prosdent.2022.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 02/03/2022] [Accepted: 02/03/2022] [Indexed: 11/30/2022]
Abstract
STATEMENT OF PROBLEM The beam profile of a light polymerization unit shows an inhomogeneous distribution. Therefore, the light passing through indirect restorations may be inhomogeneous and affect the polymerization of the resin cement. PURPOSE The purpose of this in vitro study was to investigate the effects of the inhomogeneous distribution of irradiance passing through a computer-aided design and computer-aided manufacturing (CAD-CAM) block on the microhardness of resin cement. MATERIAL AND METHODS IPS e.max CAD (A3 LT, A3 HT), Celtra Duo (A3 LT), LAVA Ultimate (A3 LT), and Vita Enamic (A3 T) blocks were tested and cut into 1.0-, 1.5-, 2.0-, and 4.0-mm thicknesses (N=100). The resin cements were Variolink N base (light-polymerized) and RelyX U200 (dual-polymerized). The light transmission, irradiance, and beam profile of each block were measured. For microhardness measurement, 5 points (-4 mm, -2 mm, 0 mm, +2 mm, and +4 mm) that coincided with the distance from the center to the periphery of the tip were marked on the specimen's surface. At each point, microhardness was measured 24 hours after polymerization. Repeated measured 1-way ANOVA with the LSD test was performed to analyze the effect of measuring points on the microhardness (α=.05). RESULTS The microhardness of the resin cements decreased with an increase of the CAD-CAM block thickness (P<.05). Resin cements under a 1-mm CAD-CAM block showed relatively uniform microhardness, whereas those under 2-mm and 4-mm blocks showed inhomogeneous microhardness (P<.05). CONCLUSIONS Inhomogeneous light transmission from a light polymerization unit through CAD-CAM blocks resulted in the nonuniform microhardness of resin cement.
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Affiliation(s)
- Yu-Ra Go
- Post graduate student, Department of Conservative of Dentistry, College of Dentistry, Yonsei University, Seoul, Republic of Korea; Resident, Department of Conservative Dentistry, Veterans Health Service Medical Center, Seoul, Republic of Korea
| | - Kwang-Man Kim
- Professor, Department and research Institute of Dental Biomaterials & Bioengineering, BK21 Project, College of Dentistry, Yonsei University, Seoul, Republic of Korea
| | - Sung-Ho Park
- Professor, Department of Conservative of Dentistry and Oral Science Research Center, Yonsei University College of Dentistry, Seoul, Republic of Korea.
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Alqutaibi AY, Ghulam O, Krsoum M, Binmahmoud S, Taher H, Elmalky W, Zafar MS. Revolution of Current Dental Zirconia: A Comprehensive Review. Molecules 2022; 27:1699. [PMID: 35268800 PMCID: PMC8911694 DOI: 10.3390/molecules27051699] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 02/16/2022] [Accepted: 03/02/2022] [Indexed: 01/27/2023] Open
Abstract
The aim of this article is to comprehensively review the revolution of dental zirconia (Zir), including its types, properties, applications, and cementation procedures. A comprehensive search of PubMed and Embase was conducted. The search was limited to manuscripts published in English. The final search was conducted in October 2021. Newly developed monolithic Zir ceramics have substantially enhanced esthetics and translucency. However, this material must be further studied in vitro and in vivo to determine its long-term ability to maintain its exceptional properties. According to the literature, monolithic translucent Zir has had promising results and a high survival rate. Thus, the utilization of this material is indicated when strength and esthetics are needed. Both the materials and methods used for cementation of monolithic Zir have significantly improved, encouraging dentists to use this material, especially when a conservative approach is required. Zir restorations showed promising outcomes, particularly for monolithic Zir crowns supported with implant and fixed dental prostheses.
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Affiliation(s)
- Ahmed Yaseen Alqutaibi
- Department of Prosthodontics, College of Dentistry, Taibah University, Al Madinah 41311, Saudi Arabia;
- Department of Prosthodontics, College of Dentistry, Ibb University, Ibb 70270, Yemen
| | - Omar Ghulam
- Dental Department, Prince Mohammad bin Abdulaziz Hospital (Ministry of National Guard-Health Affairs), Madinah 42324, Saudi Arabia; (O.G.); (M.K.); (H.T.)
| | - Majid Krsoum
- Dental Department, Prince Mohammad bin Abdulaziz Hospital (Ministry of National Guard-Health Affairs), Madinah 42324, Saudi Arabia; (O.G.); (M.K.); (H.T.)
| | - Suhail Binmahmoud
- Dental Department, Prince Sultan Armed Forces Hospital, Madinah 42375, Saudi Arabia;
| | - Hasan Taher
- Dental Department, Prince Mohammad bin Abdulaziz Hospital (Ministry of National Guard-Health Affairs), Madinah 42324, Saudi Arabia; (O.G.); (M.K.); (H.T.)
| | - Wael Elmalky
- Department of Restorative Dentistry, College of Dentistry, Taibah University, Al Madinah 41311, Saudi Arabia;
| | - Muhammad Sohail Zafar
- Department of Restorative Dentistry, College of Dentistry, Taibah University, Al Madinah 41311, Saudi Arabia;
- Department of Dental Materials, Islamic International Dental College, Riphah International University, Islamabad 44000, Pakistan
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Jung J, Roh BD, Kim JH, Shin Y. Masking of High-Translucency Zirconia for Various Cores. Oper Dent 2021; 46:54-62. [PMID: 33351930 DOI: 10.2341/19-238-l] [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: 11/26/2019] [Indexed: 11/23/2022]
Abstract
CLINICAL RELEVANCE Various core materials with different shades affect the final color of high-translucency monolithic zirconia restorations. The blue core shows the greatest color difference in final zirconia restorations followed by metal, A3 dentin-shade resin core, and white core. SUMMARY The purpose of this study was to evaluate the masking ability of high-translucency monolithic zirconia for various core materials. A computer-aided design-computer-aided manufacturing system was used to design a zirconia disc with a diameter of 10 mm and a thickness of 1.0 mm. Four groups of cores (n=15 each) were fabricated with blue-colored dual-cure resin, white-colored dual-cure resin, A3 dentin-shade composite resin, and titanium block with 10-mm diameter and 5-mm thickness.Dual-cure, self-adhesive resin cement discs with a thickness of 25.0 ± 0.02 μm were fabricated. The color was measured using a handheld spectrophotometer. Color measurements of all specimens were performed on a white background. To assess the masking ability of zirconia, the difference between the values measured with zirconia on a white background and the values measured with zirconia on each of the four types of core material as a background with the cement specimens interposed (zirconia + cement + core) was determined. To enhance the optical connection between the specimens, distilled water was applied between each layer during each measurement.The results showed that the value of ΔE was highest for the blue core followed by metal, A3 dentin-shade resin core, and white-resin core. No significant differences were observed between the metal core and the A3 dentin-shade resin core or between the A3 dentin-shade resin core and the white core. The blue core had the significantly highest ΔE value based on Tukey's honest significant difference test.Different core materials affect the final color of high-translucency monolithic zirconia restorations. Thus, our study showed that the final color of high-translucency monolithic zirconia restorations could be affected by the type of core material used.
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The influence of zirconia veneer thickness on the degree of conversion of resin-matrix cements: an integrative review. Clin Oral Investig 2021; 25:3395-3408. [PMID: 33783593 DOI: 10.1007/s00784-021-03904-w] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 03/19/2021] [Indexed: 10/21/2022]
Abstract
OBJECTIVE The main aim of this study was to conduct an integrative review on the influence of the zirconia veneer thickness on the degree of conversion of resin-matrix cements. MATERIALS AND METHOD An electronic search was performed on PubMed using a combination of the following search items: zirconia, thickness, veneer, degree of conversion, resin cement, light curing, and polymerization. Articles published in the English language, up to July 2020, were included regarding the influence of ceramic veneer thickness on the degree of conversion of resin-matrix cements. Randomized controlled trials and prospective cohort studies were also evaluated. RESULTS Of the 21 selected studies, 9 investigated the light-curing effect, while five other articles evaluated the ceramic translucency. Three studies evaluated the degree of conversion of the resin-matrix cement while four articles assessed the veneer thickness. Results revealed a significant decrease of light transmission through the zirconia with a thickness ranging from 0.1 up to 1.5 mm. However, the ultra-thin thickness around 0.1 and 0.3 mm allowed a full polymerization of the dual-curing resin-matrix cement resulting in the integrity of the interface properties. The light-curing process of resin-matrix cements is also affected by the shade, chemical composition, and microstructure of zirconia and resin cement. Optimal conditions of light-curing are required to reach the threshold intensity of light and energy for polymerization of resin-matrix cements. CONCLUSIONS The increase in zirconia veneer thickness negatively affects the degree of conversion of resin-matrix cements. Also, shade and microstructure are key factor to improve the light curing of resin cements. CLINICAL RELEVANCE Clinicians should consider the zirconia thickness on resin-based cementation since a higher veneer thickness can negatively affect the light irradiation intensity towards the dual-curing resin-matrix cement. Thus, the degree of conversion of the resin-matrix cement can decrease leading to a low chemical stability (e.g., color instability) and poor mechanical properties.
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Bonding crowns and bridges with resin cement: An American Dental Association Clinical Evaluators Panel survey. J Am Dent Assoc 2020; 151:796-797.e2. [PMID: 32979959 DOI: 10.1016/j.adaj.2020.07.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
BACKGROUND Bonding crowns and bridges with resin cement can improve retention and reinforcement of the restoration. However, there is variation in the steps taken by different practitioners to achieve this goal. METHODS The authors developed a survey on bonding dental crowns and bridges with resin cement and distributed it electronically to the American Dental Association Clinical Evaluators (ACE) Panel on May 22, 2020. The survey remained open for 2 weeks. Descriptive data analysis was conducted using SAS Version 9.4. RESULTS A total of 326 panelists responded to the survey, and 86% of respondents who place crowns or bridges use resin cements for bonding. When placing a lithium disilicate restoration, an almost equal proportion of respondents etch it with hydrofluoric acid in their office or asked the laboratory to do it for them, and more than two-thirds use a silane primer before bonding. For zirconia restorations, 70% reported their restorations are sandblasted in the laboratory, and 39% use a primer containing 10-methacryloyloxydecyl dihydrogen phosphate. One-half of respondents clean their lithium disilicate or zirconia restorations with a cleaning solution. Resin cements used with a primer in the etch-and-rinse mode are the most widely used. The technique used to cure and clean excess resin cement varies among respondents. CONCLUSIONS The types of resin cements used, tooth preparation, crown or bridge preparation, and bonding technique vary among this sample. PRACTICAL IMPLICATIONS Although many dentists bond crowns and bridges on the basis of best practices, improvement in the process may be achieved by dentists communicating with their laboratory to confirm the steps performed there, ensuring an effective cleaning technique is used after try-in and verifying that the correct primer is used with their chosen restorative material.
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Dai S, Chen C, Tang M, Chen Y, Yang L, He F, Chen B, Xie H. Choice of resin cement shades for a high-translucency zirconia product to mask dark, discolored or metal substrates. J Adv Prosthodont 2019; 11:286-296. [PMID: 31754419 PMCID: PMC6856310 DOI: 10.4047/jap.2019.11.5.286] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Revised: 10/04/2019] [Accepted: 10/29/2019] [Indexed: 11/08/2022] Open
Abstract
PURPOSE The aim was to study the masking ability of high-translucency monolithic zirconia and provide guidance in selecting resin luting cements in order to mask discolored substrates. MATERIALS AND METHODS 160 high-translucency zirconia specimens were divided into 32 groups depending on their thickness and shades. Using five shades of try-in paste, the specimens were luted onto the sub strates (Co-Cr, precious-metal, opaque porcelain-sintered Co-Cr, opaque porcelain-sintered precious-metal, and 5M3-shade zirconia). All CIELAB color parameters were measured and statistically analyzed. RESULTS Zirconia shade and thickness and try-in paste shade affected CIELAB color parameters (P=.000) in different substrates groups, and there were interactions among these factors (P=.000). All five try-in paste shades can be chosen to achieve ΔE values of zirconia with 1.2 - 1.5 mm for masking dark-tooth-like 5M3-shade and zirconia with 1.5 mm for masking precious-metal groups < 2.6. Only suitable try-in paste shades were used, can ΔE values that less than 2.6 be achieved when applied translucent monolithic zirconia with 0.7-1.0 mm for masking dark-tooth-like 5M3-shade and zirconia with 0.7 - 1.2 mm for masking precious-metal groups. CONCLUSION Choosing suitable resin cement shades is necessary for high-translucency monolithic zirconia to achieve ideal masking ability (ΔE < 2.6) on the dark-tooth.
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Affiliation(s)
- Shiqi Dai
- Jiangsu Key Laboratory of Oral Diseases; Department of Prosthodontics, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China
| | - Chen Chen
- Jiangsu Key Laboratory of Oral Diseases; Department of Endodontics, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China
| | - Mo Tang
- Jiangsu Key Laboratory of Oral Diseases; Department of Prosthodontics, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China
| | - Ying Chen
- Jiangsu Key Laboratory of Oral Diseases; Department of Prosthodontics, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China
| | - Lu Yang
- Jiangsu Key Laboratory of Oral Diseases; Department of Prosthodontics, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China
| | - Feng He
- Jiangsu Key Laboratory of Oral Diseases; Department of Prosthodontics, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China
| | - Bingzhuo Chen
- Jiangsu Key Laboratory of Oral Diseases; Department of Prosthodontics, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China
| | - Haifeng Xie
- Jiangsu Key Laboratory of Oral Diseases; Department of Prosthodontics, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China
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Clinical factors affecting the translucency of monolithic Y-TZP ceramics. Odontology 2019; 108:526-531. [DOI: 10.1007/s10266-019-00446-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 08/05/2019] [Indexed: 10/26/2022]
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Mendonça LMD, Ramalho IS, Lima LASN, Pires LA, Pegoraro TA, Pegoraro LF. Influence of the composition and shades of ceramics on light transmission and degree of conversion of dual-cured resin cements. J Appl Oral Sci 2019; 27:e20180351. [PMID: 31365707 PMCID: PMC6690711 DOI: 10.1590/1678-7757-2018-0351] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 02/01/2019] [Indexed: 12/22/2022] Open
Abstract
Objective Since the transmittance of ceramics can influence the degree of conversion (DC) of resin cements, ceramics composition and shade should be considered in the selection of resin cement. This in vitro study aimed to evaluate the effect of the transmittance of different composition, opacities and shades of ceramics on the degree of conversion of two dual-cured resin cements. Methodology Sixty discs were prepared from low translucency (LT) and medium opacity (MO) lithium disilicate ceramic, and zirconia ceramic (Z). Each group was subdivided into 5 subgroups (n=4) in shades A2, A3.5, B2, C2 and D3. The transmittance measurement was performed in a spectrophotometer. The Variolink II and Rely X U200 resin cements were photoactivated by LED (1400 mW/cm2) for 40 s through the ceramic discs and without the discs (control group). The DC was measured with infrared FTIR spectroscopy, immediately after light activation. Data were analyzed with Kruskall-Wallis and one-way ANOVA, following post-hoc comparisons by Tukey test and Pearson’s correlation test (P<0.05). Results LT ceramic exhibited higher transmittance values compared to MO and Z ceramics. LTA2 and LTB2 showed statistically higher transmittance values compared to MOA2, MOA3.5 and ZA3.5. For Variolink II, the ceramic interposition did not influence the DC, since there were no statistical differences between groups with ceramic interposition and the control group. For Rely X U200 cement, the interposition of some ceramics types/shades (LTA3.5, MOA2, MOA3.5 and ZA3.5) significantly decreased the DC values compared to control group. A positive correlation was found between the ceramic transmittance and DC values of both tested cements. Conclusions. The transmittance and DC values of the cements were influenced by composition and shades of the ceramics. The higher the transmittance of ceramics, the higher the DC values for both cements.
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Affiliation(s)
| | - Ilana Santos Ramalho
- Universidade de São Paulo, Faculdade de Odontologia de Bauru, Departmento de Prótese e Periodontia, Bauru, São Paulo, Brasil
| | | | - Laís Alcântara Pires
- Universidade de São Paulo, Faculdade de Odontologia de Bauru, Departmento de Prótese e Periodontia, Bauru, São Paulo, Brasil
| | - Thiago Amadei Pegoraro
- Universidade do Sagrado Coração, Faculdade de Odontologia, Departamento de Prótese, Bauru, São Paulo, Brasil
| | - Luiz Fernando Pegoraro
- Universidade de São Paulo, Faculdade de Odontologia de Bauru, Departmento de Prótese e Periodontia, Bauru, São Paulo, Brasil
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KURODA S, SHINYA A, GOMI H. Effect of frame design on the fracture strength of a zirconia crown and porcelain-faced crown. Dent Mater J 2019; 38:323-328. [DOI: 10.4012/dmj.2017-218] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Soichi KURODA
- Department of Crown and Bridge, The Nippon Dental University, School of Life Dentistry at Tokyo
| | - Akikazu SHINYA
- Department of Crown and Bridge, The Nippon Dental University, School of Life Dentistry at Tokyo
- Department of Prosthetic Dentistry and Biomaterials Science, Institute of Dentistry, University of Turku
| | - Harunori GOMI
- Department of Crown and Bridge, The Nippon Dental University, School of Life Dentistry at Tokyo
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Duran İ, Kaleli N, Ural Ç, Kavut İ. Evaluation of the light transmission of chairside polymer infiltrated hybrid ceramics in different shades and thicknesses. J Appl Biomater Funct Mater 2019; 17:2280800018807109. [PMID: 30803292 DOI: 10.1177/2280800018807109] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND: This in vitro study aimed to evaluate the amount of polymerizing light passing through hybrid ceramic specimens in different shades and thicknesses. METHODS: Rectangular-shaped feldspathic ceramic computer aided design and computer aided manufacturing (CAD-CAM) blocks and translucent and high translucent polymer infiltrated hybrid ceramic CAD-CAM blocks in four different shades (1M1, 1M2, 2M2, and 3M2) were sectioned in four different thicknesses (0.8, 1.5, 2, and 3 mm), and a total of 48 groups ( n = 10) were obtained. Feldspathic ceramic specimens served as the control group. The light transmission of each ceramic specimen was measured three times by using a light-emitting diode and a radiometer. Data were statistically analyzed by using univariate analysis of variance (ANOVA) followed by one-way ANOVA, Tukey honest significant difference, and Tamhane T2 tests (α = 0.05). RESULTS: Translucent polymer infiltrated hybrid ceramic specimens exhibited significantly ( p < 0.001) lower light transmission values than high translucent polymer infiltrated hybrid ceramic and feldspathic ceramic specimens, whereas feldspathic ceramic specimens exhibited significantly ( p < 0.001) higher light transmission than translucent and high translucent polymer infiltrated hybrid ceramic specimens. The amount of light transmission significantly ( p < 0.05) decreased when the shade value decreased and the thickness increased. CONCLUSIONS: Polymer infiltrated hybrid ceramic specimens showed lower light transmission values than feldspathic ceramic specimens, and the amount of light transmission was affected by the ceramic shade and thickness.
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Affiliation(s)
- İbrahim Duran
- Department of Prosthodontics, Faculty of Dentistry, Ondokuz Mayıs University, Samsun, Turkey
| | - Necati Kaleli
- Department of Prosthodontics, Faculty of Dentistry, Ondokuz Mayıs University, Samsun, Turkey
| | - Çağrı Ural
- Department of Prosthodontics, Faculty of Dentistry, Ondokuz Mayıs University, Samsun, Turkey
| | - İdris Kavut
- Department of Prosthodontics, Faculty of Dentistry, Ondokuz Mayıs University, Samsun, Turkey
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Liebermann A, Freitas Rafael C, Colle Kauling AE, Edelhoff D, Ueda K, Seiffert A, Maziero Volpato CA, Güth JF. Transmittance of visible and blue light through zirconia. Dent Mater J 2018; 37:812-817. [PMID: 29998937 DOI: 10.4012/dmj.2016-287] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [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 the transmittance of visible light (VL) (λ: 400-700 nm) and blue light (BL) (λ: 360-540 nm) through six CAD/CAM zirconia blanks (ZiB) in comparison to a lithium disilicate ceramic (LS2). Disks of the zirconia materials Bruxzir (BX), Cercon (CE), Lava Frame (LF), Lava Plus (LP), Prettau (PT), Zenostar (ZS) and LS2 (EM) were manufactured and the transmittance was measured in a spectrophotometer. ZS, followed by CE, PT, LP, LF, and BX showed the lowest transmittance of VL and BL. The highest transmittance was shown by EM. The transmittance of BL was lower than that of VL in all groups. EM ceramics showed higher transmittance than all zirconia materials and the thickness of zirconia materials influenced the transmittance values. Knowledge about VL and BL transmittance would help clinicians to individually tailor the selection of material to the specific indication and to make the right choice regarding the luting procedure and light curing duration.
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Affiliation(s)
- Anja Liebermann
- Department of Prosthetic Dentistry, Dental School, Ludwig-Maximilians Universität
| | - Caroline Freitas Rafael
- Department of Prosthetic Dentistry, Dental School, Ludwig-Maximilians Universität.,Department of Dentistry, Federal University of Santa Catarina
| | | | - Daniel Edelhoff
- Department of Prosthetic Dentistry, Dental School, Ludwig-Maximilians Universität
| | - Kazuhiko Ueda
- Comprehensive Dental Care, Oral Implant Center, Niigata Hospital, The Nippon Dental University
| | - Andreas Seiffert
- Department of Prosthetic Dentistry, Dental School, Ludwig-Maximilians Universität
| | | | - Jan-Frederik Güth
- Department of Prosthetic Dentistry, Dental School, Ludwig-Maximilians Universität
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Influence of polymerization time on properties of dual-curing cements in combination with high translucency monolithic zirconia. J Prosthodont Res 2018; 62:468-472. [PMID: 29983378 DOI: 10.1016/j.jpor.2018.06.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 06/05/2018] [Accepted: 06/10/2018] [Indexed: 11/27/2022]
Abstract
PURPOSE The aim of this in vitro study was to assess conversion degree (DC), micro-hardness (MH) and bond strength of two dual-curing resin cements employed under translucent monolithic zirconia irradiated with different time protocols. METHODS 84 square shaped samples of 1mm thickness were prepared from high translucency zirconia blocks and divided into two groups (n=24) according to the cement employed: (1) Rely-X Ultimate; (2) Panavia SA. Each group was further divided into 3 subgroups (n=8) according to the irradiation time: (a) no light; (b) 20s; (c) 120s. Light curing was performed 60s after the sample was placed on the diamond support of a FT-IR spectrophotometer with a high power multiLED lamp. Final DC% were calculated after 10min. After 24h, Vickers Test on the cement layer was performed. The same protocol was used to lute composite cylinders in order to evaluate microshear bond-strength test. ANOVA and Bonferroni tests were performed to find differences between MH and bond-strength to zirconia, while for DC% the Scheirer-Ray-Hare two-way test was used. RESULTS The two cements reached higher DC% in subgroup (b) and (c). As concern MH, statistics showed an increase in curing time was able to improve MH significantly. Bond-strength was not affected by irradiation time only for Panavia SA. CONCLUSIONS The first null hypothesis has to be rejected since DC% and MH of the dual-cements tested were influenced by the curing time. The second null hypothesis is partially rejected since the bond strength was influenced by the curing time only for Rely-X Ultimate.
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Tosiriwatanapong T, Singhatanadgit W. Zirconia-Based Biomaterials for Hard Tissue Reconstruction. ACTA ACUST UNITED AC 2018. [DOI: 10.1177/1179061x18767886] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Implantable biomaterials are increasingly important in the practice of modern medicine, including fixative, replacement, and regeneration therapies, for reconstruction of hard tissues in patients with pathologic osseous and dental conditions. A number of newly developed advanced biomaterials have been introduced as promising candidates for tissue reconstruction. Among these, zirconia-based biomaterials have gained attention as a biomaterial for hard tissue reconstruction due to superior mechanical properties and good chemical and biological compatibilities. This review summarizes the types of zirconia, advantages of zirconia-based biomaterials for hard tissue reconstruction including bone and dental tissues, responses of tissue and cells to zirconia, and surface modifications for enhanced bioactivity of zirconia. Current and future applications of zirconia-based biomaterials for bone and dental reconstruction, ie, medical implanted devices, dental prostheses, and biocompatible osteogenic scaffolds, are also discussed.
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Sen N, Sermet IB, Cinar S. Effect of coloring and sintering on the translucency and biaxial strength of monolithic zirconia. J Prosthet Dent 2018; 119:308.e1-308.e7. [DOI: 10.1016/j.prosdent.2017.08.013] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 08/24/2017] [Accepted: 08/25/2017] [Indexed: 10/18/2022]
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Ilie N. Impact of light transmittance mode on polymerisation kinetics in bulk-fill resin-based composites. J Dent 2017; 63:51-59. [DOI: 10.1016/j.jdent.2017.05.017] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 05/24/2017] [Accepted: 05/24/2017] [Indexed: 11/29/2022] Open
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ZIMMERMANN M, EGLI G, ZARUBA M, MEHL A. Influence of material thickness on fractural strength of CAD/CAM fabricated ceramic crowns. Dent Mater J 2017; 36:778-783. [DOI: 10.4012/dmj.2016-296] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Moritz ZIMMERMANN
- Department of Computerized Restorative Dentistry, Center of Dental Medicine, University of Zurich
| | - Gustav EGLI
- Department of Computerized Restorative Dentistry, Center of Dental Medicine, University of Zurich
| | - Markus ZARUBA
- Department of Computerized Restorative Dentistry, Center of Dental Medicine, University of Zurich
| | - Albert MEHL
- Department of Computerized Restorative Dentistry, Center of Dental Medicine, University of Zurich
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Stawarczyk B, Awad D, Ilie N. Blue-Light Transmittance of Esthetic Monolithic CAD/CAM Materials With Respect to Their Composition, Thickness, and Curing Conditions. Oper Dent 2016; 41:531-540. [DOI: 10.2341/15-252-l] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
SUMMARY
Determining the amount of blue light (360-540nm) passing through nine monolithic computer-aided design/computer-aided manufacturing (CAD/CAM) materials depends on material thickness, initial irradiance, and the distance between the curing unit and the specimen's surface. A total of 180 specimens of two thicknesses (1 mm and 2 mm, n=10/subgroup) were fabricated from TelioCAD, VITA CAD-Temp (VCT), experimental nanocomposite, LAVA Ultimate (LU), VITA ENAMIC (VE), VITA MarkII (VM), IPS EmpressCAD (IEC), IPS e.maxCAD (IEM), and CELTRA DUO (CD). The irradiance passing through the CAD/CAM materials and thicknesses was measured using a light-emitting-diode curing unit with standard-power, high-power, and plasma modes by means of a USB4000 spectrometer. The curing unit was placed directly on the specimen's surface at 2- and 4-mm distances from the specimen's surface. Data were analyzed using a multivariate analysis and one-way analysis of variance with the post hoc Scheffé test (p<0.05). The highest transmitted irradiance was measured for VM and LU, followed by VCT and IEC, while the lowest values showed VE, followed by IEM and CD. The highest transmitted irradiance was recorded by exposing the material to the plasma mode, followed by the high- and standard-power modes. The measured irradiance was decreased by increasing the specimen's thickness from 1 to 2 mm. Fewer differences were measured when the curing unit was placed at 0 or 2 mm from the specimen's surface, and the irradiance passing through the specimens was lower at a distance of 4 mm.
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Affiliation(s)
- B Stawarczyk
- Bogna Stawarczyk, PD Dr. Dipl. Ing. (FH), MSc, Department of Prosthodontics, Dental School, Ludwig-Maximilians University, Munich, Germany
| | - D Awad
- Daniel Awad, Dr. Dent. Med., Department of Operative/Restorative Dentistry, Periodontology, and Pedodontics, Ludwig-Maximilians University, Munich, Germany
| | - N Ilie
- Nicoleta Ilie, Prof. Dr. Dipl. Ing., Department of Operative/Restorative Dentistry, Periodontology, and Pedodontics, Ludwig-Maximilians University, Munich, Germany
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Ilie N. Transmitted irradiance through ceramics: effect on the mechanical properties of a luting resin cement. Clin Oral Investig 2016; 21:1183-1190. [PMID: 27352903 DOI: 10.1007/s00784-016-1891-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 06/15/2016] [Indexed: 11/24/2022]
Abstract
OBJECTIVES The study aims to characterise the curing behaviour of a light-curing luting composite (Variolink® Aesthetic LC, Ivoclar Vivadent) polymerised at different exposure times (10 s, 20 s) through different ceramics (IPS Empress CAD and IPS e.max CAD, Ivoclar Vivadent) and ceramic thicknesses (no ceramic, 0.5, 1, 1.5 and 2 mm). MATERIAL AND METHOD Curing units' (Bluephase Style, Ivoclar Vivadent) variation in irradiance delivered up to 10-mm exposure distance as well as the incident and transmitted irradiance and radiant exposure up to 6-mm ceramic thickness were assessed on a laboratory-grade spectrometer. A total of 216 (18 groups, n = 12) thin and flat luting composite specimens of 500-μm thickness were prepared and stored after curing in a saturated vapour atmosphere for 24 h at 37 °C. Micro-mechanical properties (Vickers hardness, HV and indentation modulus, YHU) were determined by means of an automatic micro-hardness indenter. RESULTS Within the study design, the radiant exposure received by the luting composite varied from 2.56 to 24.75 J/cm2, showing a high impact on the measured properties. Comparing the effect of the parameters exposure time, ceramic thickness and type, the highest influence on the micro-mechanical parameters was identified for exposure time, while this influence was stronger on HV (p < 0.001, η P2 = 0.452) than on YHU (p < 0.001, η P2 = 0.178). The influence of ceramic type was significant but low (η P2 = 0.161 on HV and 0.113 on YHU), while the influence of ceramic thickness was the lowest (η P2 = 0.04 and 0.05, respectively). CONCLUSIONS Slightly higher irradiance values were transmitted through Empress CAD up to a ceramic thickness of 3 mm (p < 0.001), while being comparable with e.max for thicker slices. Differences in translucency between ceramics were reflected in the micro-mechanical properties of the luting composite. CLINICAL RELEVANCE The radiant exposure reaching the luting composite is determined by the incident irradiance, exposure time, ceramic type and ceramic thickness. At the analysed incident irradiance, exposure time was the most consistent parameter affecting the micro-mechanical properties of the luting composite, and this effect was strongly reflected in the more translucent ceramic Empress CAD. Within the curing conditions, an exposure time of 20 s is recommended.
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Affiliation(s)
- Nicoleta Ilie
- Department of Operative/Restorative Dentistry, Periodontology and Pedodontics, Ludwig-Maximilians University of Munich, Goethestr. 70, 80336, Munich, Germany.
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Malkondu Ö, Tinastepe N, Akan E, Kazazoğlu E. An overview of monolithic zirconia in dentistry. BIOTECHNOL BIOTEC EQ 2016. [DOI: 10.1080/13102818.2016.1177470] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Affiliation(s)
- Özlem Malkondu
- Faculty of Dentistry, Department of Prosthodontics, Yeditepe University, Istanbul, Turkey
| | - Neslihan Tinastepe
- Faculty of Dentistry, Department of Prosthodontics, Yeditepe University, Istanbul, Turkey
| | - Ender Akan
- Faculty of Dentistry, Department of Prosthodontics, İzmir Katip Çelebi University, Izmir, Turkey
| | - Ender Kazazoğlu
- Faculty of Dentistry, Department of Prosthodontics, İzmir Katip Çelebi University, Izmir, Turkey
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Transmission of light in the visible spectrum (400–700 nm) and blue spectrum (360–540 nm) through CAD/CAM polymers. Clin Oral Investig 2016; 20:2501-2506. [DOI: 10.1007/s00784-016-1755-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Accepted: 02/12/2016] [Indexed: 11/26/2022]
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Stawarczyk B, Frevert K, Ender A, Roos M, Sener B, Wimmer T. Comparison of four monolithic zirconia materials with conventional ones: Contrast ratio, grain size, four-point flexural strength and two-body wear. J Mech Behav Biomed Mater 2015; 59:128-138. [PMID: 26751707 DOI: 10.1016/j.jmbbm.2015.11.040] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 11/17/2015] [Accepted: 11/23/2015] [Indexed: 12/28/2022]
Abstract
OBJECTIVES To test the mechanical and optical properties of monolithic zirconia in comparison to conventional zirconia. MATERIALS AND METHODS Specimens were prepared from: monolithic zirconia: Zenostar (ZS), DD Bio ZX(2) hochtransluzent (DD), Ceramill Zolid (CZ), InCoris TZI (IC) and a conventional zirconia Ceramill ZI (CZI). Contrast ratio (N=75/n=15) was measured according to ISO 2471:2008. Grain sizes (N=75/n=15) were investigated with scanning electron microscope. Four-point flexural strength (N=225/n=15/zirconia and aging regime) was measured initially, after aging in autoclave or chewing simulator (ISO 13356:2008). Two-body wear of polished and glazed/veneered specimens (N=108/n=12) was analyzed in a chewing simulator using human teeth as antagonists. Data were analyzed using 2-/1-way ANOVA with post-hoc Scheffé, Kruskal-Wallis-H, Mann-Whitney-U, Spearman-Rho, Weibull statistics and linear mixed models (p<0.05). RESULTS The lowest contrast ratio values were found for ZS and IC and CZ. IC showed the largest grain size followed by DD and CZI. The smallest grain size was observed for ZS followed by CZ. There was no correlation between grain size and contrast ratio. The aging regime showed no impact on flexural strength. All non-aged and autoclave-aged specimens showed lower flexural strengths than the control group CZI. Within groups aged in chewing simulator, ZS showed significantly lower flexural strength than CZI. CZI showed higher material and antagonist wear than monolithic polished and glazed groups. Glazed specimens showed higher material and antagonist loss compared to polished ones. There was no correlation between roughness and wear. CONCLUSIONS Monolithic zirconia showed higher optical, but lower mechanical properties than conventional zirconia.
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Affiliation(s)
- Bogna Stawarczyk
- Department of Prosthodontics, Dental School, Ludwig-Maximilians-University of Munich, Germany.
| | - Kathrin Frevert
- Department of Prosthodontics, Dental School, Ludwig-Maximilians-University of Munich, Germany
| | - Andreas Ender
- Clinic of Preventive Dentistry, Periodontology and Cariology, Center of Dental Medicine, University of Zurich, Switzerland
| | - Malgorzata Roos
- Department of Biostatistics, Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Switzerland
| | - Beatrice Sener
- Clinic of Preventive Dentistry, Periodontology and Cariology, Center of Dental Medicine, University of Zurich, Switzerland
| | - Timea Wimmer
- Department of Prosthodontics, Dental School, Ludwig-Maximilians-University of Munich, Germany
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Translucency of Dental Ceramic, Post and Bracket. MATERIALS 2015; 8:7241-7249. [PMID: 28793634 PMCID: PMC5458893 DOI: 10.3390/ma8115379] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 10/21/2015] [Indexed: 11/16/2022]
Abstract
Translucency of dental ceramics, esthetic posts and orthodontic brackets was reviewed. Translucency parameter (TP) and contrast ratio (CR) are generally used for translucency evaluation. For the evaluation of translucency, two criteria such as the translucency of human teeth (TP = 15-19, 1 mm thick) and the visual perceptibility threshold for the translucency difference (∆CR > 0.07 or ∆TP > 2) were used. In ceramics, translucency differences were in the perceptible range depending on the type of material and the thickness. However, variations caused by the difference in the required thickness for each layer by the material and also by the measurement protocols should be considered. As to the translucency of esthetic posts, a significant difference was found among the post systems. Translucency was influenced by the bracket composition and brand, and the differences by the brand were visually perceptible.
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Ueda K, Güth JF, Erdelt K, Stimmelmayr M, Kappert H, Beuer F. Light transmittance by a multi-coloured zirconia material. Dent Mater J 2015; 34:310-4. [PMID: 25904173 DOI: 10.4012/dmj.2014-238] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Full-contour zirconia restorations are gaining in popularity. Highly translucent zirconia materials and multi-coloured zirconia blocks might help to overcome the aesthetic drawbacks of traditional zirconia. This study evaluated the transmittance of visible light (400-700 nm) through the four different layers (Enamel Layer EL, Transition Layer 1 TL1, Transition Layer 2 TL2, Body Layer BL) of a multi-coloured zirconia block (KATANA™ Zirconia Multi-Layered Disc (ML)) using a spectrophotometer. Forty specimens (thickness of 1±0.05 mm) from each layer were examined and statistically evaluated at a confidence-level of 5%. Light transmittance was expressed as a percentage of the through-passing light. The following mean values (SD) were found: EL 32.8% (1.5), TL1 31.2% (1.3), TL2 25.4% (1.3) and BL 21.7% (1.1). Significant differences were found between all groups (ANOVA, Student-Newman-Keuls). This multi-coloured zirconia block showed four layers with different light transmittance capabilities. It might therefore be useful for enhancing the aesthetic appearance of full-contour zirconia restorations made from this material.
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Affiliation(s)
- Kazuhiko Ueda
- Comprehensive Dental Care, Oral Implant Center, Niigata Hospital, Nippon Dental University
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Quantification of the amount of light passing through zirconia: the effect of material shade, thickness, and curing conditions. Br Dent J 2014. [DOI: 10.1038/sj.bdj.2014.829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Johnston WM. Review of translucency determinations and applications to dental materials. J ESTHET RESTOR DENT 2014; 26:217-23. [PMID: 24975048 DOI: 10.1111/jerd.12112] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
STATEMENT OF PROBLEM There are several ways to measure the translucency of materials, as various basic colorimetric concepts have been used to describe the translucency of natural and esthetic dental materials. There are currently no guidelines regarding which method to use to describe the translucency of these materials. PURPOSES OF STUDY Two initial purposes of this study are to review the initial developments of the major translucency measurement methods first in the color science literature and then in the dentistry literature, and to review in the dentistry literature the recent uses of the various translucency measurement methods in light of the objectives of the presented research. MATERIAL AND METHODS A major color science textbook was reviewed to obtain the background information and selected references regarding the original methods of opacity measurement and the original references regarding the development and use of a translucency parameter were also reviewed. Then the recent dentistry literature was reviewed to describe the uses of the various methods of opacity or translucency determinations for various dental materials. RESULTS The three major methods of translucency measurement were found to be contrast ratio, transmittance, and translucency parameter, with the contrast ratio and transmittance methods each having the possibility of being either luminous or spectral. Translucency measurements were mainly used to describe dental resin composites and dental ceramic materials, but prosthetic elastomers, fiber posts, orthodontic brackets, natural tooth dentine and enamel, and combinations of materials were also studied using at least one of these methods. CONCLUSIONS The more-developed use of models that relate the thickness of the translucent materials to the translucency measurement of interest is encouraged. Also, care must be taken when comparing previously generated translucency measurements with any newly generated data because technical details of the thickness and the backings used in previous research must be matched or adjustments must be made to make any newly generated data comparable with published values. CLINICAL SIGNIFICANCE The method of specifying the translucency of esthetic dental materials may be based on clinical appearance requirements of the patient, on technical demands of optimizing the setting of underlying material, or on both. The method or methods used to describe translucency may provide clinically relevant information in order for the clinician to select the optimum material to satisfy these requirements.
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Affiliation(s)
- William M Johnston
- Division of General Dentistry and Materials Science, College of Dentistry, The Ohio State University, Columbus, OH, USA
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