레진 나노 세라믹 계열 하이브리드 블록의 마모도 및 색 안정성 평가 = Evaluation of Wear and Color Stability of Resin Nanoceramic Hybrid Blocks

다국어 초록 (Multilingual Abstract)

The use of CAD/CAM restorative materials has increased with the development of digital dentistry. Resin nanoceramic hybrid blocks have been introduced to combine the esthetic properties of ceramics with the resilience and machinability of resin-based materials. However, their long-term clinical performance may be influenced by wear under repeated masticatory loading and optical changes in staining environments. Therefore, this in vitro study evaluated the wear resistance, color stability, and translucency changes of three commercially available resin nanoceramic hybrid blocks.
Three resin nanoceramic hybrid blocks were used: Mazic Duro(Vericom Co., Ltd., Chuncheon, Korea), NT Mill(Denbio Co., Ltd., Gwangju, Korea), Shofu Block HC(Shofu Inc., Kyoto, Japan). For the wear test, cylindrical specimens were subjected to 120,000, 240,000, or 500,000 chewing cycles using a chewing simulator under dry conditions with a metal antagonist. Volumetric wear loss was calculated by scanning the specimens before and after chewing simulation and performing digital subtraction. For the color stability test, disc-shaped specimens were immersed in distilled water, coffee solution, and red wine for up to 4 weeks. Color measurements were performed at baseline, 1 day, 1 week, 2 weeks, and 4 weeks using a spectrophotometer. Color difference was calculated as ΔE*, and translucency changes were evaluated using the translucency parameter (TP) and the change in translucency parameter (ΔTP). The data were statistically analyzed to evaluate the effects of material, chewing cycle, immersion solution, and time.
In the wear test, no significant difference in wear volume was observed among the three materials, whereas wear increased significantly with repeated chewing cycles. These findings indicate that the tested resin nanoceramic hybrid blocks showed comparable wear resistance under the experimental conditions, and that wear was more strongly influenced by repeated loading than by material type.
In the color stability test, ΔE* values increased over time and were higher in the coffee and wine groups than in the distilled water groups. Translucency changes differed depending on the immersion solution and material-solution combination. In particular, the wine group showed a tendency toward decreased translucency, and NT Mill exhibited relatively greater color change and translucency reduction under wine immersion.
Within the limitations of this in vitro study, the three resin nanoceramic hybrid blocks showed comparable wear resistance, while their optical stability varied depending on the staining environment and material-solution combination. These results suggest that resin nanoceramic hybrid blocks may be clinically applicable in terms of wear resistance; however, esthetic requirements, dietary habits, and long-term maintenance should be considered when selecting these materials for clinical use.

목차 (Table of Contents)

• Ⅰ. 서론 1
• Ⅱ. 연구 대상 및 방법 3
• Ⅲ. 연구 결과 12
• Ⅳ. 고찰 24
• Ⅴ. 결론 29
• VI. 참고 문헌 30