PubMed ID (PMID): 22141231Pages 219-226, Language: English, GermanHmaidouch, Rim / Neumann, Peter / Mueller, Wolf-Dieter
Purpose: To evaluate the influence of two different tooth preparation forms, two luting space settings and two cement types on the marginal and internal adaptation of all-ceramic crown copings produced using Cerec3® CAD/CAM system.
Materials and Methods: Forty working stone dies were made from two metal master casts (1. Tooth 36: with anatomic occlusal reduction, 2. Tooth 36: with flat occlusal reduction). Forty crown copings were milled using Vita In-Ceram 2000 YZ: 20 with an luting space settings of 0 = 100 µm and 20 with -50 = 50 µm. Copings were cemented using two cements (zinc phosphate cement, P21: Panavia21®), then embedded and sectioned bucco-lingually and mesio-distally. Widths of marginal and internal gaps were measured using a light microscope at magnification of 40X. Data were submitted to one-way ANOVA, and statistical significance was set at p < 0.05.
Results: Copings with flat occlusal reduction and luting space settings of 100 µm had a better internal and marginal fit compared with copings with anatomic occlusal reduction and luting space settings of 50 µm, regardless of the cement used. P21 showed a significantly better fit compared with zinc phosphate cement.
Conclusion: The presented Cerec3 CAD/CAM system can provide a marginal and internal adaptation which is comparable to that of conventional cast and conventional allceramic crowns.
Keywords: all-ceramic copings, luting space setting, internal gap, marginal gap