Homsy F, Bottin M, Özcan M, Majzoub Z
Lebanese University, Faculty of Dental Medicine.
Biesse Dental Srl, Montà, PD, Italy.
Eur J Prosthodont Restor Dent. 2019 Feb 22;27(1):18-25. doi: 10.1922/EJPRD_01828Homsy08.
The impact of material on the adaptation of lithium disilicate inlays is poorly documented. This in vitro study aims at comparing the fit accuracy of pressed and milled inlays obtained from conventional impression and laboratory-based computer-aided design and computer-aided manufacturing.
A typodont molar was prepared for a mesio-occlusal ceramic inlay. The stone die generated from one conventional impression was scanned once using a laboratory scanner and the same design was used to produce 15 pressed lithium disilicate inlays from milled wax patterns (group CIDW), and 15 inlays from lithium disilicate blanks (group CICAD) with a 5-axis milling machine. Marginal and internal discrepancies were measured using the replica technique. Mixed-model ANOVA was applied to assess differences according to material and gap location at P⟨0.05.
Material and discrepancy location had a significant effect on fit measurements. Group CIDW showed significantly smaller marginal (37.4 μm) and internal (69.2 μm) discrepancies than group CICAD (59.6 μm and 93.7 μm respectively). Marginal discrepancies were significantly smaller than internal discrepancies within both groups.
Pressed inlays generated from conventional impression and milled wax patterns yielded better fit accuracy than milled inlays obtained from conventional impression and subtractive manufacturing.
材料对二硅酸锂嵌体适配性的影响鲜有文献记载。本体外研究旨在比较通过传统印模以及基于实验室的计算机辅助设计与计算机辅助制造获得的压制嵌体和铣削嵌体的适配精度。
为一颗模型磨牙制备近中咬合面陶瓷嵌体。使用实验室扫描仪对由一次传统印模制作的石膏模型扫描一次，采用相同设计，用5轴铣床从铣削蜡型制作15个压制二硅酸锂嵌体（CIDW组），并从二硅酸锂坯料制作15个嵌体（CICAD组）。使用复制技术测量边缘和内部差异。应用混合模型方差分析，以评估在P<0.05时根据材料和间隙位置的差异。
材料和差异位置对适配测量有显著影响。CIDW组的边缘差异（37.4μm）和内部差异（69.2μm）明显小于CICAD组（分别为59.6μm和93.7μm）。两组内边缘差异均明显小于内部差异。
由传统印模和铣削蜡型制作的压制嵌体比由传统印模和减材制造获得的铣削嵌体具有更好的适配精度。
