Rafael B Junqueira1, Rodrigo F Carvalho2, Felipe A G F Yamamoto3, Solange M Almeida4, Francielle S Verner5. 1. Division of Endodontics, Department of Dentistry, Federal University of Juiz de Fora, Campus GV (UFJF-GV), Governador Valadares, Minas Gerais, Brazil. 2. Division of Prosthodontics, Department of Dentistry, Federal University of Juiz de Fora, Campus GV (UFJF-GV), Governador Valadares, Minas Gerais, Brazil. 3. Hospital Maternidade Therezinha de Jesus-HMTJ/JF and Suprema - Faculdade Ciências Médicas e da Saúde Juiz de Fora (SUPREMA), Juiz de Fora, Minas Gerais, Brazil. 4. Division of Oral Radiology, Department of Oral Diagnosis, Piracicaba Dental School, State University of Campinas (UNICAMP), Piracicaba, São Paulo, Brazil. 5. Division of Oral Diagnosis, Department of Dentistry, Federal University of Juiz de Fora, Campus GV (UFJF-GV), Governador Valadares, Minas Gerais, Brazil.
Abstract
PURPOSE: To evaluate the radiopacity of luting cements submitted to different aging procedures. MATERIALS AND METHODS: Twenty discs (1 × 4 mm) of each of the following cements were prepared: zinc phosphate, RelyX Luting 2, Variolink 2, AllCem, RelyX U200, Multilink, Panavia F2.0, and RelyX ARC. Then, they were randomly divided into two groups (n = 10/group), according to the aging procedure: thermal cycling group and water storage group. Before and after aging procedures, specimens were x-rayed with an aluminum step-wedge (11 steps, 1 mm thick each) and three dental slices (1 mm thick). The radiopacity was evaluated by means of optical density, which was measured using ImageJ software. The values were converted into millimeters of aluminum with a logistic regression calibration curve. The data were analyzed by one-way ANOVA and Tukey post-hoc test (α = 0.05). RESULTS: In the thermal cycling group, RelyX Luting 2, RelyX U200, and Panavia F2.0 showed a statistically significant reduction in radiopacity (p < 0.05). In the water storage group, all cements showed a significant reduction in radiopacity (p < 0.05), and RelyX Luting 2 and Panavia F2.0 performed below the desired ISO 4049 standard. CONCLUSIONS: The radiopacity of luting cements can decrease after aging, especially after 1-year water storage.
PURPOSE: To evaluate the radiopacity of luting cements submitted to different aging procedures. MATERIALS AND METHODS: Twenty discs (1 × 4 mm) of each of the following cements were prepared: zinc phosphate, RelyX Luting 2, Variolink 2, AllCem, RelyX U200, Multilink, Panavia F2.0, and RelyX ARC. Then, they were randomly divided into two groups (n = 10/group), according to the aging procedure: thermal cycling group and water storage group. Before and after aging procedures, specimens were x-rayed with an aluminum step-wedge (11 steps, 1 mm thick each) and three dental slices (1 mm thick). The radiopacity was evaluated by means of optical density, which was measured using ImageJ software. The values were converted into millimeters of aluminum with a logistic regression calibration curve. The data were analyzed by one-way ANOVA and Tukey post-hoc test (α = 0.05). RESULTS: In the thermal cycling group, RelyX Luting 2, RelyX U200, and Panavia F2.0 showed a statistically significant reduction in radiopacity (p < 0.05). In the water storage group, all cements showed a significant reduction in radiopacity (p < 0.05), and RelyX Luting 2 and Panavia F2.0 performed below the desired ISO 4049 standard. CONCLUSIONS: The radiopacity of luting cements can decrease after aging, especially after 1-year water storage.