Brunna Mota Ferrairo1, Fernanda Furtado Piras2, Feranda Ferruzzi Lima3,4, Heitor Marques Honório5, Marco Antonio Hungaro Duarte6, Ana Flávia Sanches Borges6, José Henrique Rubo7. 1. Department of Prosthodontics and Periodontics, Bauru School of Dentistry, University of São Paulo, Alameda Doutor Octávio Pinheiro Brisolla, 9-75, Bauru, SP, 17012-901, Brazil. brunna.ferrairo@usp.br. 2. Department of Prosthodontics and Periodontology, Faculty of Dentistry, University of Marília (UNIMAR), Avenida Higino Muzi Filho, 1001, Marília, SP, 17525-902, Brazil. 3. Department of Dentistry, Maringá State University, Maringá, PR, Brazil. 4. Department of Restorative Dentistry and Prosthodontics, Ingá University Center - UNINGÁ, School of Dentistry, Maringá, PR, Brazil. 5. Department of Pediatric Dentistry, Orthodontics and Public Health, Bauru School of Dentistry, University of São Paulo, Alameda Doutor Octávio Pinheiro Brisolla, 9-75, Bauru, SP, 17012-901, Brazil. 6. Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Alameda Doutor Octávio Pinheiro Brisolla, 9-75, Bauru, SP, 17012-901, Brazil. 7. Department of Prosthodontics and Periodontics, Bauru School of Dentistry, University of São Paulo, Alameda Doutor Octávio Pinheiro Brisolla, 9-75, Bauru, SP, 17012-901, Brazil.
Abstract
OBJECTIVES: To evaluate the marginal adaptation and internal space of crowns produced by 4 CAD/CAM systems using microcomputed tomography (μCT) and replica technique (RT). MATERIALS AND METHODS: Monolithic lithium disilicate crowns were milled (Ceramill, Cerec, EDG, and Zirkonzahn) (n = 10). The cement film obtained with low viscosity silicone was scanned by the μCT system and captured by a stereomicroscope, according to RT. Two-way ANOVA followed by Tukey's test were used for statistical analysis (α = 0.05). A uniformity index (UI) was idealized to describe the distribution of crowns' internal space and submitted to the Kruskal-Wallis and Tukey's test (α = 0.05). The correlation between μCT and RT was performed by Pearson's Correlation Coeficient (α = 0.05). RESULTS: Marginal adaptation and internal space were statistically significant different between the experimental groups for the μCT and RT (p < 0.05). The medians of the 4 systems tested were within clinically acceptable range and the mean (± SD) highest marginal discrepancy was recorded in the Ceramill group at 133.0 ± 71.5 μm (μCT) and 90.6 ± 38.5 μm (RT). For internal fit, the UI disclosed a better distribution of the internal space for the Zirkonzahn group (p < 0.001). There was a strong correlation between the methods (p = 0.01 and r = 0.69). CLINICAL RELEVANCE: Because of the variability of the CAD/CAM systems available, evaluating their accuracy is of clinical interest. The 4 systems are capable to produce restorations adaptated within clinically appropriate levels. The μCT and RT are efficient adaptation methodologies.
OBJECTIVES: To evaluate the marginal adaptation and internal space of crowns produced by 4 CAD/CAM systems using microcomputed tomography (μCT) and replica technique (RT). MATERIALS AND METHODS: Monolithic lithium disilicate crowns were milled (Ceramill, Cerec, EDG, and Zirkonzahn) (n = 10). The cement film obtained with low viscosity silicone was scanned by the μCT system and captured by a stereomicroscope, according to RT. Two-way ANOVA followed by Tukey's test were used for statistical analysis (α = 0.05). A uniformity index (UI) was idealized to describe the distribution of crowns' internal space and submitted to the Kruskal-Wallis and Tukey's test (α = 0.05). The correlation between μCT and RT was performed by Pearson's Correlation Coeficient (α = 0.05). RESULTS: Marginal adaptation and internal space were statistically significant different between the experimental groups for the μCT and RT (p < 0.05). The medians of the 4 systems tested were within clinically acceptable range and the mean (± SD) highest marginal discrepancy was recorded in the Ceramill group at 133.0 ± 71.5 μm (μCT) and 90.6 ± 38.5 μm (RT). For internal fit, the UI disclosed a better distribution of the internal space for the Zirkonzahn group (p < 0.001). There was a strong correlation between the methods (p = 0.01 and r = 0.69). CLINICAL RELEVANCE: Because of the variability of the CAD/CAM systems available, evaluating their accuracy is of clinical interest. The 4 systems are capable to produce restorations adaptated within clinically appropriate levels. The μCT and RT are efficient adaptation methodologies.