Influence of contemporary CAD-CAM milling systems on the fit and adaptation of partially stabilized Zirconia fixed partial dentures

摘要

Objective: To evaluate marginal fit and internal adaptation of three-unit Zr frameworks fabricated from four Zr CAD/CAM milling systems. Methods: Fixed partial denture models were replicated (40 stone models) using Polyvinyl Siloxane impression material (PVS) and type IV stone for Zr framework fabrication. FPDs were milled with four CAD/CAM systems, Group-II: LAVA? Zirconia milled by LAVA?, Group-2: Vita In-Ceram YZ milled by Cerec?, Group-3: Zirconia milled by GM1000 and Group-4: Zirconia milled by DWX-50N. Twelve marginal gap measurements per framework were performed at pre-established points, with a metallurgical microscope (Zeiss, Germany) at 500X magnification. Eight measurements of cement space per section were performed for adaptation. Data was analyzed using ANOVA and Tukey post hoc test. Results: Zirconia FPD frameworks exhibited gaps ranging from 16 to 50.1 μm for marginal fit and 26.8 to 102.5 μm for internal adaptation. Group-3 [20.8 (8.3) μm & 50.3 (11.4) μm] and Group-4 [16.0 (4.0) μm & 40.2 (8.8) μm] specimens showed significantly lower marginal fit and internal adaptation gaps compared to Group-I [50.1 (13.4) μm & 100.5 (16.7) μm] and Group-2 [38.9 (8.2) μm & 102.5 (13.4) μm] specimens respectively. Conclusions: Different CAD-CAM systems for fabrication of Zr FPD frameworks displayed a significant influence on marginal fit and internal adaptation of restorations. doi: https://doi.org/10.12669/pjms.37.1.3490 How to cite this:Al-Aali KA, Alhamdan RS, Maawadh AM, Vohra F, Abduljabbar T. Influence of contemporary CAD-CAM milling systems on the fit and adaptation of partially stabilized Zirconia fixed partial dentures. Pak J Med Sci. 2021;37(1):45-51.??doi: https://doi.org/10.12669/pjms.37.1.3490 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.