Zhao Si Ming, Wang Xiao Yan
Department of Cariology and Endodontology, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices & Beijing Key Laboratory of Digital Stomatology & NHC Research Center of Engineering and Technology for Computerized Dentistry & NMPA Key Laboratory for Dental Materials, Beijing 100081, China.
Beijing Da Xue Xue Bao Yi Xue Ban. 2023 Dec 18;55(6):1105-1110. doi: 10.19723/j.issn.1671-167X.2023.06.023.
To investigate the influence of 135° and 90° cavity design on quality of margin and marginal adaptation and microleakage of all-ceramic computer aided design/computer aided manufacturing (CAD/CAM) inlays.
One hundred extracted human molars were prepared by criteria of buccal occlusal (BO) inlay. On the buccal, the mesial margin was prepared as 135° bevel while the distal margin was prepared as butt-joint. All-ceramic restorations were made in the Sirona CEREC AC CAD/CAM system with VitaBlocs Mark Ⅱ, Upcera UP.CAD, IPS e.max CAD, Upcera Hyramic and Lava Ultimate. The gaps between each inlay's mesial margin-abutment and distal margin-abutment were recorded under an optical microscope. Each inlay was adhered to the abutment and aged by thermal cycling for 10 000 times. Each specimen was cut into 3 slices after staining. Dye penetration was evaluated under an optical microscope for mesial and distal margins.
Mean marginal integrity rate, mean marginal gap value and mean depth of microleakage of 135° margin of Group Upcera Hyramic and Lava Ultimate were significantly better than those of Group VitaBlocs Mark Ⅱ, Upcera UP.CAD and IPS e.max CAD( < 0.05). Mean marginal gap value, mean depth of microleakage and scale of mean depth of microleakage of 90° margin of Group Upcera Hyramic and Lava Ultimate were significantly better than those of Group Upcera UP.CAD and IPS e.max CAD ( < 0.05) while mean marginal integrity rate was not significantly different (>0.05). Mean marginal integrity rate of 90° margin was significantly better than that of 135° margin in each group ( < 0.05) while mean depth of microleakage between different margins was not significantly different in each group (>0.05). Mean marginal gap value of 90° margin of Group VitaBlocs Mark Ⅱ and IPS e.max CAD was significantly better than that of 135° margin ( < 0.05) while there was not significant difference in other 3 groups between 90° and 135° margin (>0.05). Scale of mean depth of microleakage of 135° margin of Group Upcera Hyramic and Lava Ultimate was significant better than that of 90° margin ( < 0.05) while there was not significantly different in other 3 groups between 90° and 135° margin (>0.05).
The mesial and distal margins of abutement of all-ceramic inlay should be prepared as butt-joint.
探讨135°和90°洞型设计对全瓷计算机辅助设计/计算机辅助制造（CAD/CAM）嵌体边缘质量、边缘适合性及微渗漏的影响。
按照颊面咬合（BO）嵌体标准对100颗拔除的人磨牙进行预备。在颊面，近中边缘预备成135°斜面，远中边缘预备成对接。使用VitaBlocs Mark Ⅱ、Upcera UP.CAD、IPS e.max CAD、Upcera Hyramic和Lava Ultimate在Sirona CEREC AC CAD/CAM系统中制作全瓷修复体。在光学显微镜下记录每个嵌体近中边缘-基牙和远中边缘-基牙之间的间隙。将每个嵌体粘结到基牙上，并通过热循环老化10000次。染色后将每个标本切成3片。在光学显微镜下评估近中边缘和远中边缘的染料渗透情况。
Upcera Hyramic组和Lava Ultimate组135°边缘的平均边缘完整性率、平均边缘间隙值和平均微渗漏深度显著优于VitaBlocs Mark Ⅱ组、Upcera UP.CAD组和IPS e.max CAD组（P<0.05）。Upcera Hyramic组和Lava Ultimate组90°边缘的平均边缘间隙值、平均微渗漏深度和平均微渗漏深度范围显著优于Upcera UP.CAD组和IPS e.max CAD组（P<0.05），而平均边缘完整性率无显著差异（P>0.05）。每组中90°边缘的平均边缘完整性率显著优于135°边缘（P<0.05），而每组中不同边缘之间的平均微渗漏深度无显著差异（P>0.05）。VitaBlocs Mark Ⅱ组和IPS e.max CAD组90°边缘的平均边缘间隙值显著优于135°边缘（P<0.05），而其他3组90°和135°边缘之间无显著差异（P>0.05）。Upcera Hyramic组和Lava Ultimate组135°边缘的平均微渗漏深度范围显著优于90°边缘（P<0.05），而其他3组90°和135°边缘之间无显著差异（P>0.05）。
全瓷嵌体基牙的近中边缘和远中边缘应预备成对接形式。
