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Kelma Palacio Gomes Magalhães A, Barros Moreira G, Loíky Sampaio de Souza M, Whitehurst Ary Leitão A, Fernandes Peixoto R, Pontes C, Matthes de Freitas Pontes K. Evaluation of one versus two glaze firings on the color stability and mechanical properties of an extrinsically characterized monolithic CAD-CAM lithium disilicate glass ceramic. J Prosthodont 2023. [PMID: 37947149 DOI: 10.1111/jopr.13792] [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: 01/18/2023] [Accepted: 11/05/2023] [Indexed: 11/12/2023] Open
Abstract
PURPOSE To evaluate the effects of 1 versus 2 glaze firings on the color and mechanical properties of an extrinsically characterized lithium disilicate ceramic after thermal cycling, brushing, or both. MATERIALS AND METHODS Eighty specimens were divided into 2 groups: 1 glaze firing (GL1) and 2 glaze firings (GL2). Each group was subdivided into 4 groups (n = 10), according to the experimental conditions: thermal-cycling, brushing, thermal-cycling + brushing, and immersion in distilled water (control). Color variation, surface roughness, and Vickers microhardness were analyzed before each designated experiment and after the simulated periods of 2.5, 5, and 10 years. Three-way mixed ANOVA was used for all outcomes, followed by 1-way ANOVA, repeated measures 1-way ANOVA, Bonferroni post hoc test, and t-test to check for statistical differences (α = 0.05). RESULTS Thermal cycling generated greater color changes in the GL1 group at 2.5 and 5 years (p < 0.001; p = 0.013). Brushing generated color changes in GL1 at 5 years (p = 0.003) and in GL2 at 10 years (p = 0.017). Regarding surface roughness, the GL1 group suffered alterations in thermal cycling + brushing at 5 years. In the control group, the GL1 group exhibited higher roughness values than GL2 (p < 0.05). Most of the groups experienced an increase in microhardness at 2.5 years (p < 0.05). In the GL1 group, thermal-cycling increased the microhardness at 5 years (p = 0.006); at 5 and 10 years, the GL1 group had a higher microhardness than the GL2 in thermal-cycling + brushing (p < 0.05). CONCLUSION Ceramics with 1 glaze firing showed greater color, roughness, and microhardness changes compared to those submitted to 2 firings.
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Affiliation(s)
| | - Gabriela Barros Moreira
- Department of Restorative Dentistry, School of Dentistry, Federal University of Ceara (UFC), Fortaleza, Ceara, Brazil
| | | | | | - Raniel Fernandes Peixoto
- Department of Restorative Dentistry, School of Dentistry, Federal University of Ceara (UFC), Fortaleza, Ceara, Brazil
| | - Cássio Pontes
- Department of Restorative Dentistry, School of Dentistry, São Leopoldo Mandic College, São Paulo, Campinas, Brazil
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Tavangar MS, Mousavipour E, Ansarifard E. The effect of bleaching on the optical and physical properties of externally stained monolithic zirconia. Clin Exp Dent Res 2021; 7:861-867. [PMID: 34155828 PMCID: PMC8543453 DOI: 10.1002/cre2.433] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 03/21/2021] [Accepted: 03/25/2021] [Indexed: 11/30/2022] Open
Abstract
Objective This study aimed to investigate the effects of bleaching on the color, translucency, surface roughness, and surface hardness of monolithic zirconia with external stainin . Methods In this experimental study, 32 specimens of monolithic zirconia (1 × 1 mm; shade A2) were divided into two groups based on random permuted blocks. Overglaze and staining procedures were performed with a yellow stain or a value stain (GC Stain). Baseline color, translucency, roughness, and surface hardness were measured. The specimens were then randomly bleached with hydrogen peroxide (HP) 40% (20 min, twice with a 1‐week interval in between) as office bleaching or carbamide peroxide (CP) 20% (4 h per day for 14 days) as home bleaching. Finally, the color, translucency, surface roughness, and surface hardness were measured again. Results Bleaching with CP and HP caused a perceptible change in the color of the specimens (ΔE > 2), although this change was within the clinically acceptable range (ΔE < 3.3). HP significantly reduced the surface hardness of the specimens (p = 0.043). Changes in surface roughness of the specimens were neither statistically nor clinically significant (p = 0.19 and p = 0.25 for office and home bleaching, respectively). Conclusion The effects of home and office bleaching on the surface characteristics of monolithic zirconia were almost the same. It is not necessary to exchange or even to polish the surfaces of zirconia restorations after exposure to bleaching agents. Further studies are recommended to confirm the color stability of externally stained monolithic zirconia.
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Affiliation(s)
- Maryam S Tavangar
- Operative Dentistry Department, Dental Faculty, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Elaheh Mousavipour
- Students' Research Committee, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Elham Ansarifard
- Department of Prosthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.,Nanobiology and Nanomedicine Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
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Abstract
Aim: To investigate the effect of toothbrushing on different stained Computerd Aided Design/Computer Aided Manufacturing CAD/CAM ceramics. Materials and Methods: Fifty specimens (high translucency zirconia, YZHT; zirconia-reinforced lithium silicate, ZLS; feldspathic, FDL; hybrid ceramic, HC; all from Vita Zahnfabrik) were divided into five groups according to their staining technique. ZLS allowed the composition of two groups: ZLS1 with crystallization and staining together; ZLS2, with the stain firing after the crystallization. YZHT received a stain firing after the sintering process, and FDL received stain firing directly. The HC was stained with acrylic staining, and was light-cured on its surface. The specimens were brushed in total for 150,000 cycles at 2.45 N with 180 strokes/min. Surface measurements to obtain Rz were performed after 50,000, 100,000 and 150,000 cycles, with five evaluation lines (5 mm) per specimen orthogonal to the brushing direction, covering brushed and unbrushed areas. The wear was analyzed using two-way ANOVA and Tukey tests (α = 5%). Scanning electron microscopy (SEM) was performed to access the surface profile. The wear was affected by material (p < 0.001) and time (p = 0.139). Superior wear (µm) was observed for HC (6.6 ± 4.4; 6.8 ± 4.0; 9.2 ± 3.5) compared to ZLS2 (1.0 ± 0.3; 1.2 ± 2.2; 1.3 ± 0.3), YZHT (1.0 ± 0.1; 1.2 ± 0.3; 1.2 ± 0.3), ZLS1 (0.9 ± 0.1; 1.1 ± 0.5; 1.2 ± 0.3) and FDL (0.9 ± 0.1; 0.9 ± 0.1; 1.0 ± 0.2) after 5, 10 and 15 years of simulation, respectively. SEM showed different wear patters for HC with the removal of the glaze layer. HC showed a higher staining wear rate compared to the glass-based and polycrystalline ceramics after 15 years. The extrinsic characterization of feldspathic ceramic showed its superior longevity compared to the evaluated high-translucency zirconia, zirconia-reinforced lithium silicate, and hybrid ceramic.
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Miranda JS, Barcellos ASP, MartinelliLobo CM, Caneppele TMF, Amaral M, Kimpara ET. Effect of staining and repeated firing on the surface and optical properties of lithium disilicate. J ESTHET RESTOR DENT 2019; 32:113-118. [PMID: 31854512 DOI: 10.1111/jerd.12558] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 12/03/2019] [Accepted: 12/10/2019] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Evaluate the effect of staining and repeated firings on color, translucency and surface proprieties of CAD/CAM lithium disilicate (LD). MATERIAL AND METHODS One hundred eighty LD discs were made (ISO 6872) and distributed in different groups (n = 20): control (CO)-no treatment; single-step characterization (SC)-crystallization and staining fired together; and double step characterization (DC)-crystallization and then staining. The samples were submitted to two, four, or six firings, resulting in nine groups: COII, COIV, COVI, SCII, SCIV, SCVI, DCII, DCIV, and DCVI. The color and translucency were measured by a reflectance spectrophotometer. Surface roughness (Ra) and Vickers nano-hardness were also measured. ANOVA and Tukey statistical tests were used (α = .05). RESULTS Only CO and DC demonstrated significant color alterations (ΔE00 > 1.8). SC and DC did not show changes in translucency by the number of firings (P > .05); however, for CO (P = .02) these values increased. Nano-hardness was similar in all groups (P > .05). Ra values indicated differences due to the type of characterization (SC presented the highest values) and number of firings (CO and DC groups) (P < .01). CONCLUSION SC promoted color, translucency, and roughness stability after repeated firings. CLINICAL SIGNIFICANCE The single characterization technic in CAD/CAM lithium disilicate presents good color, translucency, and hardness stability, which promote predictable results to monolithic restoration.
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Affiliation(s)
- Jean S Miranda
- Department of Dental Materials and Prosthodontics, São José dos Campos Dental School, Institute of Science and Technology, UNESP-Paulista State University, São José dos Campos, Brazil
| | - Aline S P Barcellos
- Department of Dental Materials and Prosthodontics, São José dos Campos Dental School, Institute of Science and Technology, UNESP-Paulista State University, São José dos Campos, Brazil
| | - Carolina M MartinelliLobo
- Department of Dental Materials and Prosthodontics, São José dos Campos Dental School, Institute of Science and Technology, UNESP-Paulista State University, São José dos Campos, Brazil
| | - Taciana M F Caneppele
- Department of Restorative Dentistry, São José dos Campos Dental School, Institute of Science and Technology, UNESP-Paulista State University, São José dos Campos, Brazil
| | - Marina Amaral
- Department of Dentistry, University of Taubaté, Taubaté, Brazil
| | - Estevão T Kimpara
- Department of Dental Materials and Prosthodontics, São José dos Campos Dental School, Institute of Science and Technology, UNESP-Paulista State University, São José dos Campos, Brazil
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OLIVEIRA CBD, GANDINI JÚNIOR LG, SANTOS-PINTO A. Efeito da escovação e das bebidas na rugosidade superficial de bráquetes cerâmicos. REVISTA DE ODONTOLOGIA DA UNESP 2018. [DOI: 10.1590/1807-2577.07418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Resumo Introdução Quando introduzidos no meio bucal, os bráquetes cerâmicos podem sofrer alterações em sua estrutura provocadas pelo processo de degradação química e mecânica do material. Objetivo Este estudo avaliou a rugosidade superficial de bráquetes cerâmicos e se eles sofreram alteração com a escovação dentária e a imersão em bebidas com diferentes pH. Material e método Foram testados sete bráquetes cerâmicos de incisivo central superior direito de quatro marcas comerciais (duas marcas de bráquete monocristalino e duas de policristalino). Os bráquetes foram imersos em soluções de café, vinho tinto, Coca-Cola, chá preto e saliva artificial durante 21 dias. Outros sete bráquetes de cada marca comercial foram imersos nas mesmas soluções e no mesmo tempo, porém com intervalos de escovação diários realizados por uma máquina de escovação. A rugosidade (Ra) foi obtida por meio de um rugosímetro (Surftest SJ-400, Mitutoyo®) antes e após 24 horas, 7, 14 e 21 dias. Os dados foram avaliados pela análise de perfis multivariados, análise de variância (ANOVA) e teste de comparação múltipla de médias. Resultado Os resultados da rugosidade e de sua alteração após 21 dias foram: média Ra do Allure = 0,277 μm (alteração = 0,002 μm), Inspire Ice = 0,262 μm (alteração = 0,013 μm), Radiance = 0,177 μm (alteração = 0,009 μm) e Transcend = 0,367 μm (alteração = 0,019 μm). Conclusão A rugosidade superficial dos bráquetes cerâmicos aumentou após 21 dias de imersão nas soluções, sendo o tempo de imersão um fator significante. No entanto, essa alteração da rugosidade no tempo é semelhante nos bráquetes monocristalinos e policristalinos, assim como nas diferentes soluções. A escovação dentária não produziu alteração na rugosidade superficial de bráquetes cerâmicos.
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Yuan JCC, Barão VAR, Wee AG, Alfaro MF, Afshari FS, Sukotjo C. Effect of brushing and thermocycling on the shade and surface roughness of CAD-CAM ceramic restorations. J Prosthet Dent 2017; 119:1000-1006. [PMID: 28965682 DOI: 10.1016/j.prosdent.2017.06.001] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 06/01/2017] [Accepted: 06/01/2017] [Indexed: 11/16/2022]
Abstract
STATEMENT OF PROBLEM The effects of toothbrushing (B) and thermocycling (TC) on the surface texture of different materials with various fabrication processes have been investigated. However, studies of computer-aided design and computer-aided manufacturing (CAD-CAM) ceramic restorations are limited. PURPOSE The purpose of this in vitro study was to evaluate the effect of B and TC on the color stability and surface roughness of extrinsically characterized and glazed CAD-CAM ceramic restorations. MATERIAL AND METHODS Lithium disilicate CAD ceramic (n=90) and zirconia ceramic (n=90) were studied. All specimens were crystallized/sintered, characterized, and glazed following the manufacturer's recommendation. The specimens were divided into 9 different groups: B, TC, and a combination of B plus TC (B+TC). Brushing was performed at 50 000, 100 000, and 150 000 cycles, simulating an oral environment of 5, 10, and 15 years. Thermocycling was performed at 6000, 12 000, and 18 000 cycles, simulating an oral environment of 5, 10, and 15 years. Brushing plus TC was performed with the combination of the 50 000 cycles of B, then 6000 cycles of TC, and 10 000 cycles of B, then 12 000 cycles of TC, and 15 000 cycles of B, then 18 000 cycles of TC. The color and surface roughness of each specimen were measured before and after all interventions with simulated cycles. Color differences (ΔE) and surface roughness (ΔRa) data were analyzed using 2-way ANOVA, followed by the least significant difference test (α=.05). The correlation between ΔE and ΔRa was statistically analyzed using the Pearson correlation analysis. RESULTS Within the lithium disilicate CAD groups, intervention did not result in any significant differences in color change (P>.05). Within the zirconia groups, a 15-year clinical simulation revealed significantly higher ΔE values than a simulated 5-year exposure (P=.017). Increased simulated cycles showed significantly higher Ra values for all groups. Within the zirconia groups, B revealed significantly smoother surfaces than TC (P<.001) and B+TC interventions (P<.001). For the zirconia, simulating B+TC for15 years revealed significantly higher Ra values than the groups of B+TC for 5 years (P<.001) and B+TC for 10 years (P=.003). No correlation (lithium disilicate CAD, r=.079; P=.462; zirconia, r=.001; P=.989) was found between the color change and surface roughness. CONCLUSIONS For both lithium disilicate CAD and zirconia, color changes were below the selected clinical perceptible threshold (ΔE=2.6) after all intervention and simulated cycles. All mean surface roughness measurements were below 0.2 μm. Generally, the surface of both lithium disilicate CAD and zirconia became rougher. No correlation was found between color difference and surface roughness for either material.
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Affiliation(s)
- Judy Chia-Chun Yuan
- Associate Professor and Predoctoral Implant Program Director, Department of Restorative Dentistry, University of Illinois at Chicago, College of Dentistry, Chicago, Ill.
| | - Valentim Adelino Ricardo Barão
- Assistant Professor, Department of Prosthodontics and Periodontology, Piracicaba Dental School, University of Campinas, San Paolo, Brazil
| | - Alvin G Wee
- Section Head, Maxillofacial Prosthodontics, Veteran's Affairs Nebraska Western Iowa Health Care System, Omaha, Neb, and Special Associate Professor, Department of Prosthodontics, Creighton University School of Dentistry, Omaha, Neb
| | - Maria F Alfaro
- Former Assistant Director of Digital Oral Health Science and Technology, Department of Restorative Dentistry, University of Illinois at Chicago, College of Dentistry, Chicago, Ill; Prosthodontics resident, Department of Biological and Materials Sciences and Division of Prosthodontics, University of Michigan School of Dentistry, Ann Arbor, Mich
| | - Fatemeh S Afshari
- Clinical Associate Professor, Department of Restorative Dentistry, University of Illinois at Chicago, College of Dentistry, Chicago, Ill
| | - Cortino Sukotjo
- Associate Professor, Department of Restorative Dentistry, University of Illinois at Chicago, College of Dentistry, Chicago, Ill
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Garza LA, Thompson G, Cho SH, Berzins DW. Effect of toothbrushing on shade and surface roughness of extrinsically stained pressable ceramics. J Prosthet Dent 2015; 115:489-94. [PMID: 26589442 DOI: 10.1016/j.prosdent.2015.09.013] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 09/28/2015] [Accepted: 09/30/2015] [Indexed: 11/27/2022]
Abstract
STATEMENT OF PROBLEM The effect of toothbrushing on extrinsically stained pressable ceramic materials is unknown. PURPOSE The purpose of this in vitro study was to investigate the effects of toothbrushing on the shade and surface roughness of extrinsically stained, pressable ceramics. MATERIAL AND METHODS Two materials, leucite-based (IPS Empress Esthetic [EE]; Ivoclar Vivadent AG) and lithium disilicate-based ceramic (IPS e.max Press [EP]; Ivoclar Vivadent AG), were studied. For each material, 24 disk-shaped specimens, 10 mm (diameter)×3 mm (height) were fabricated. Three different methods (n=8) of applying extrinsic stains were performed on each material: glazed only (G, control group); stained then glazed (SG); and stained and glazed together (T). The specimens were brushed with a multistation brushing machine under a load of 1.96 N at a rate of 90 strokes per minute with a soft and straight toothbrush (Oral-B #35) and a 1:1 toothpaste and distilled water slurry. Shade and roughness were measured at baseline and at 72, 144, 216, and 288 hours, which is equivalent to 3, 6, 9, and 12 years of simulated toothbrushing for 2 minutes twice a day. A repeated measures ANOVA with staining technique as a fixed factor was used to evaluate shade and roughness (α=.05). RESULTS For EE groups, no significant change was found after 12 years of simulated toothbrushing regarding shade and surface roughness, irrespective of staining techniques (P>.05). However, EP groups demonstrated a significant shade change and an increase in surface roughness after 12 years of simulated toothbrushing. Shade change was found to depend on the method of applying stain. For the EP-SG technique, a significant shade change was observed only at the 9- to 12-year interval (P=.047). However, the EP-T technique demonstrated a significant difference in shade between baseline and 3 years (P=.005) and in the 6- to 9-year interval (P=.005). Surface roughness was only significantly affected at baseline and 3 years for the EP-T group (P=.005). CONCLUSIONS For the shade and surface roughness of the EE groups, no statistically significant difference was found after 12 years of toothbrushing, irrespective of the staining technique. The shade and surface roughness of the EP groups were significantly statistically affected by toothbrushing time; only shade changes were found to depend on technique.
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Affiliation(s)
- Lessly A Garza
- Resident, Graduate Prosthodontics, Marquette University School of Dentistry, Milwaukee, Wis
| | - Geoffrey Thompson
- Assistant Professor and Program Director, Postgraduate Program in Prosthodontics, Marquette University School of Dentistry, Milwaukee, Wis
| | - Seok-Hwan Cho
- Assistant Professor and Director, Predoctoral Prosthodontics and Biomaterials, Department of General Dental Sciences, Marquette University School of Dentistry, Milwaukee, Wis.
| | - David W Berzins
- Associate Professor and Director, Department of General Dental Sciences, Graduate Dental Biomaterials, Marquette University School of Dentistry, Milwaukee, Wis
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Cho MS, Lee YK, Lim BS, Lim YJ. Changes in optical properties of enamel porcelain after repeated external staining. J Prosthet Dent 2006; 95:437-43. [PMID: 16765156 DOI: 10.1016/j.prosdent.2006.04.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
STATEMENT OF PROBLEM After staining a porcelain restoration, increasing the lightness (value) and decreasing the chroma of a restoration is not practically easy to accomplish. PURPOSE The purpose of this study was to determine the color change of enamel porcelain after repeated external staining procedures over the enamel porcelain surface. Changes in translucency and differences in surface roughness were also measured. MATERIAL AND METHODS Enamel porcelain (VITA OMEGA 900 Metal Ceramics) disks (1 x 12 mm) of 1 shade (EN2) were prepared, and 1 of 4 types of external stains (VITA Akzent stains) was applied over the specimens and fired. Firing was repeated 3 times after application of the same stains. Color of the specimens before and after stainings was measured with a reflection spectrophotometer. Two-factor repeated-measures analysis of variance with the fixed factors of the stain type and number of staining cycles for the changes in CIE L(*), CIE a(*), CIE b(*), color (DeltaE(*)(ab)), and chroma (DeltaC(*)(ab)) after repeated staining was performed (alpha=.05). Chroma change was calculated as DeltaC(*)(a)=(Deltaa *(2) +Deltab *(2))(1/2). Changes in translucency (translucency parameter and masking effect) and difference in surface roughness (Ra) after the third staining cycle were also determined. RESULTS Color change after the first staining cycle was perceptible (DeltaE(*)(ab) >2) for 2 of 4 types of stains and was perceptible for all 4 types of stains investigated after the third staining cycle (DeltaE(*)(ab) = 2.36-11.04). Lightness generally increased, and chroma also increased after staining but varied by the type of stains and number of staining cycles. Translucency generally decreased after repeated staining. Surface roughness varied by the type of stain (P < .001). CONCLUSION Color difference and lightness increased significantly after repeated staining cycles, but chroma change was small after repeated staining cycles. Therefore, repeated staining may be a method to increase the lightness of enamel porcelain.
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Affiliation(s)
- Moon-Sang Cho
- Department of Dental Biomaterial Science, Dental Research Institute, College of Dentistry, Seoul National University, Korea
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Abstract
The degradation of dental ceramics generally occurs because of mechanical forces or chemical attack. The possible physiological side-effects of ceramics are their tendency to abrade opposing dental structures, the emission of radiation from radioactive components, the roughening of their surfaces by chemical attack with a corresponding increase in plaque retention, and the release of potentially unsafe concentrations of elements as a result of abrasion and dissolution. The chemical durability of dental ceramics is excellent. With the exception of the excessive exposure to acidulated fluoride, ammonium bifluoride, or hydrofluoric acid, there is little risk of surface degradation of virtually all current dental ceramics. Extensive exposure to acidulated fluoride is a possible problem for individuals with head and/or neck cancer who have received large doses of radiation. Such fluoride treatment is necessary to minimize tooth demineralization when saliva flow rates have been reduced because of radiation exposure to salivary glands. Porcelain surface stains are also lost occasionally when abraded by prophylaxis pastes and/or acidulated fluoride. In each case, the solutes are usually not ingested. Further research that uses standardized testing procedures is needed on the chemical durability of dental ceramics. Accelerated durability tests are desirable to minimize the time required for such measurements. The influence of chemical durability on surface roughness and the subsequent effect of roughness on wear of the ceramic restorations as well as of opposing structures should also be explored on a standardized basis.
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Affiliation(s)
- K J Anusavice
- College of Dentistry, University of Florida, Gainesville 32610
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