Effect of surface treatments and universal adhesive on bond strength of silica-containing CAD/CAM blocks

학위논문(박사) -- 서울대학교 대학원 : 치과대학 치의과학과, 2024. 8. 임범순.실리카를 함유한 CAD/CAM용 블록에 대한 접착강도는 블록의 구성 성분과 미세구조, 표면처리 및 적용한 접착제의 특성 등에 영향을 받을 수 있다. 본 연구에서는 다양한 조성의 실리케이트계 블록을 샌드블라스 팅 또는 불산 (HF)으로 처리한 후 universal adhesive로 접착한 컴포짓 트 레진의 전단접착강도를 측정하였으며, 추가로 실란 (silane) 프라이머 적용에 따른 접착강도 변화를 평가하였다. 실리카 함유 블록으로 하이브리드 컴포짓트 세라믹 블록 2 종 (VTE, AMH), 백류석-강화형 글라스-세라믹 블록 1 종 (EMP) 및 리듐-다이실 리케이트 글라스-세라믹 3 종 (EMX, AMM 및 RSS) 등 모두 다양한 유 형의 블록 6 종을 선택하였고, 임상에서 사용하는 universal adhesive 제 품 5 종 (ABU, PBU, SBU, EZU 및 HBU)을 선정하여 블록의 표면처리 가 접착강도에 주는 영향을 평가하였다. 실리케이트계 블록 표면을 매끈 하게 연마한 후 일부는 불산 (4.5 % HF, 60초)으로 처리하고, 일부는 알 루미나로 샌드블라스팅-처리 (50 μm alumina)한 후 표면거칠기, 젖음성 및 미세구조 등을 CLSM (Confocal Laser Scanning Microscope), Contact Angle Analyzer 및 FE-SEM (Field Emission Scanning Electron Micro- scope)으로 분석하였고, universal adhesive로 컴포짓트 레진 (지름 2 mm)을 접착시켜 37℃ 수조에서 24시간 보관한 다음 만능시험기를 이용 하여 1.0 mm/min의 하중속도로 전단접착강도를 측정하였다. 표면거칠기, 젖음성 및 접착강도 측정값들은 Tukey-multiple comparison test (α = 0.05)로 통계 분석하여 다음의 결과를 얻었다. 1. 하이브리드 컴포짓트 세라믹의 경우에는 샌드블라스팅 또는 HF-처리 에 따른 접착력의 유의한 차이가 없었고 (p>0.05), universal adhesive 로 접착하는 경우 실란 프라이머의 추가 적용에 따라 접착력의 유의 한 증가는 관찰되지 않았다. 2. 백류석-강화형 글라스-세라믹에서는 샌드블라스팅-처리 시 universal adhesive를 적용하더라도 적절한 접착력을 얻기 위하여 실란 프라이 머를 반드시 추가로 적용하는 것이 필요하였다. 반면, HF-처리한 경 우에는 EZU universal adhesive는 실란 프라이머의 추가적용에 따라 접착력이 많이 증가 했지만, 나머지 universal adhesive는 접착력이 조금 증가하면서 유의미한 증가는 관찰되지 않았다. 3. 리듐-다이실리케이트 글라스-세라믹 경우에서도 백류석-강화형 글라 스-세라믹과 유사하게 샌드블라스팅-처리 보다 HF-처리가 접착에 유리하였으며, 샌드블라스팅-처리시 universal adhesive를 적용하더라 도 반드시 실란 프라이머를 추가로 적용하는 것이 필요하였다. 반면, HF-처리한 경우에는 실란 프라이머를 적용하지 않았을 때, PBU와 EZU universal adhesive는 매우 낮은 접착력을 보였지만, 실란 프라 이머를 적용시 모든 universal adhesive에서 유의미한 접착력의 증가 가 관찰되었다. 그중 ABU와 HBU universal adhesive는 실란 프라이 머 추가 적용에 따라 접착력이 조금 증가했지만, 다른 universal adhesive는 접착력이 크게 증가하는 것으로 관찰되어 적용한 universal adhesive에 따른 차이를 보였다.The bond strength to the silica-containing CAD/CAM blocks may be affected by their compositions and microstructures, surface treatments, and the properties of the applied adhesive. In this study, the shear bond strength to the silicate blocks with various universal adhesives after sandblasting or HF-treatment was measured, and the effects of the additional silane application after surface treatments are also evaluated. Six silica-containing blocks [two hybrid composite ceramic (VTE, AMH), one leucite-reinforced glass ceramic (EMP), and three lithium- disilicate glass-ceramic (EMX, AMM, and RSS)] and five universal adhesives (ABU, PBU, SBU, EZU, and HBU) currently used in dental clinics were selected. After polishing the surface of the silicate blocks, the specimens were divided into two groups. The first groups were sandblasted (50 μm alumina) and the second groups were HF- treated (4.5 % HF, 60 sec), and the surface roughness, contact angle, and microstructure were analyzed by CLSM (Confocal Laser Scanning Microscope), Contact Angle Analyzer, and FE-SEM (Field Emission Scanning Electron Microscope). Composite resin (2 mm in diameter) was bonded with universal adhesive to silicate blocks (with/without additional silane primer) and stored in a 37 ℃ water bath for 24 hours, and the shear bond strength was measured using a universal testing machine. The measured values were statistically analyzed using the Tukey-multiple comparison test (α = 0.05), and the following results were obtained. 1. For hybrid composite ceramics, there were no significant differences in shear bond strength between sandblasting and HF-treatments (p > 0.05), no significant increases in bond strength were observed with additional application of silane primer when bonding with universal adhesive. 2. For leucite-reinforced glass-ceramic, even when using the universal adhesive for bonding, it was necessary to apply an additional silane primer to achieve adequate adhesion for sandblasted blocks. On the contrary, in the HF-treated blocks, bond strength was significantly increased for EZU universal adhesive with the additional application of silane primer, while for the others, there was no significant increase observed in bond strength with the additional application of silane primer. 3. For lithium-disilicate glass-ceramics, similar to the leucite-reinforced glass ceramics, the HF-treatment favored adhesion over the sandblasting. For the sandblasted blocks, even with the application of a universal adhesive, it was necessary to apply an additional silane primer. On the other hand, for the HF-treated blocks, PBU and EZU universal adhesive showed little adhesive strength without the additional application of silane primer. However, with the additional application of silane primer, a significant increase in adhesion was observed in all five universal adhesives, which varied depending on the applied universal adhesive; ABU, HBU universal adhesive showed a little increase in the shear bond strength, while the other universal adhesives showed a big increase in the shear bond strength with the additional application of silane primer. For hybrid composite ceramics, additional silane primer application may not be necessary when bonding with a universal adhesive regardless of surface treatment methods, whereas for leucite-reinforced glass-caramic and lithium-disilicate glass-ceramics, HF-treatment may be more favorable for adhesion than sandblasting, and additional silane primer application appears to be necessary to sandblasted blocks.표면처리와 universal adhesive가 실리카 함유 CAD/CAM 블록의 접착력에 주는 영향 서울대학교 대학원 치의과학과 치과생체재료과학 전공 (지도교수 : 임 범 순) 박 치 용 목 차 Ⅰ. 서 론 Ⅱ. 연구 재료 및 방법 Ⅲ. 연구 결과 Ⅳ. 총괄 및 고찰 Ⅴ. 결 론 참고 문헌 영문 초록박

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