IADR Abstract Archives
Accuracy of Ceramic Restorations made with different CAD/CAM milling systems
Objectives: The purpose of this study was to evaluate the marginal fit of CAD/CAM ceramic crown restorations manufactured with the CEREC Bluecam system associated with two different milling units; MC compact (Cerec 3 milling unit) and MC XL.
Methods: Sixteen pre-molar typodont plastic teeth were divided into two groups (n=8) according to the milling unit assigned The control group (G1): Cerec Bluecam/Compact MC milling unit and G2: Cerec Bluecam/MC XL milling unit. All teeth received a full crown preparation respecting the manufacturer’s recommendation for enamel/dentin reduction. Scanning of the preparation and crown design were performed using the Cerec Optispray and Cerec Bluecam acquisition unit. Crowns were designed using the Cerec 4.2 software version and then milled using Vita-Mark II ceramic blocks. After completing the milling step, crowns were cemented to the reference plastic teeth using epoxy glue on the pulpal floor only and finger pressure for 1 min. Upon completion of the cementation step, misfit between the restoration and abutment were measured by microphotography and the silicone replica technique using light body silicon material on Mesial (M) and Distal (D) surfaces of teeth.
Results: Mean and SDs of marginal gaps in micrometers were: G1/M: 94.90 (38.52), G1/D: 88.53 (44.87), G2/M: 85.65 (29.89), G2/D: 95.28 (28.13). Two-way ANOVA indicated no significant differences among different groups (P>0.05); surface area (P>0.05) and the interaction (P>0.05). Overall, G2 had greater margin gaps than G1, however, without statistical difference (P>0.05).
Conclusions: Marginal gap means were in the range of the clinical acceptance levels for both generations of Cerec milling units, regardless the teeth site area.
Methods: Sixteen pre-molar typodont plastic teeth were divided into two groups (n=8) according to the milling unit assigned The control group (G1): Cerec Bluecam/Compact MC milling unit and G2: Cerec Bluecam/MC XL milling unit. All teeth received a full crown preparation respecting the manufacturer’s recommendation for enamel/dentin reduction. Scanning of the preparation and crown design were performed using the Cerec Optispray and Cerec Bluecam acquisition unit. Crowns were designed using the Cerec 4.2 software version and then milled using Vita-Mark II ceramic blocks. After completing the milling step, crowns were cemented to the reference plastic teeth using epoxy glue on the pulpal floor only and finger pressure for 1 min. Upon completion of the cementation step, misfit between the restoration and abutment were measured by microphotography and the silicone replica technique using light body silicon material on Mesial (M) and Distal (D) surfaces of teeth.
Results: Mean and SDs of marginal gaps in micrometers were: G1/M: 94.90 (38.52), G1/D: 88.53 (44.87), G2/M: 85.65 (29.89), G2/D: 95.28 (28.13). Two-way ANOVA indicated no significant differences among different groups (P>0.05); surface area (P>0.05) and the interaction (P>0.05). Overall, G2 had greater margin gaps than G1, however, without statistical difference (P>0.05).
Conclusions: Marginal gap means were in the range of the clinical acceptance levels for both generations of Cerec milling units, regardless the teeth site area.