Marginal fit of CAD CAM all ceramic inlays - preliminary study

Aim of the study. Marginal fit of the all ceramic chair side CAD CAM inlays evaluation. Materials and methods. Inlay class II standardized preparations were performed on twelve natural teeth (molars) which were adapted and fixed on a typodont. Scanning of the cavities was done (Planmeca FIT) and the milling of the inlays was realized (Planmeca Mill 40). Light body silicone (Fit Checker II, GC, Tokyo, Japan) was injected on the preparations of the typodont model, and then each of the Empress CAD inlays were seated on the abutments under finger pressure, reproducing the clinical situation of the luting process. The marginal gap between the all ceramic inlays and the cavities was measured using microscopic photos of the silicone fit checker between the inlays and the cavities in 12 points/restoration. A calibration scale and imaging computer software (Image J) were used for the measurements. Results The values measured for the occlusal cavity (marginal occlusal) were ranged between 19.026 mu and 139.669 mu and the values for the vertical cavity (marginal cervical) ranged between 69.256 it and 295.091. Marginal openings below 100 mu-120 mu are clinically acceptable so there where some problems regarding the cervical fit. Conclusion Within the limits of this study there were some cases with poor cervical marginal fit. Extensive studies could be useful for more accurate evaluations.