CAD/CAM용 신소재 컴포짓트 블럭의 마모도 평가

Abstract

CAD/CAM generated dental restorations meet standardized manufacturing processes with uniform material quality, reproducibility of restorations and reduction in production costs. CAD/CAM systems in dentistry have rapidly gained importance and popularity, then various types of composite block were introduced as novel material. The purpose of this study were to evaluate the wear resistance of dental novel composite blocks for CAD/CAM. Five composite resin blocks (Lava Ultimate, Block HC, Cerasmart, KZR-CAD HR, Polyglass) and one composite ceramic block (Vita Enamic) for CAD/CAM were tested. Wear was simulated with an OHSU oral wear simulator, which simultaneously incorporates the wear mechanism of attrition and abrasion in three-body wear mode. Composite specimens were subjected to 50,000 cycles of wear against a steatite antagonist. Mixture of poppy seeds (2 g) and PMMA beads (1 g) in DW (10㎖) was used for 3-body abrasive medium. After wear simulation, average wear depths for abrasion wear and attrition wear were measured with the use of a 3D profilometer. Ten specimens were tested each group. Composite blocks showed excellent abrasion wear resistance (1.74-3.45 ㎛) except for Polyglass. Cerasmart showed the lowest attrition wear (5.85 ㎛), there were no significantly difference in attrition wear (12.28-14.07 ㎛) for the other four composite blocks (p>0.05). Composite ceramic block showed the similar wear behavior to composite resin blocks. Correlation between fraction of ceramic and wear resistance was very low (R2 = 0.1684).