Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, Plattenstrasse 11, CH-8032 Zurich, Switzerland.
Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, Plattenstrasse 11, CH-8032 Zurich, Switzerland.
J Dent. 2022 Jun;121:104121. doi: 10.1016/j.jdent.2022.104121. Epub 2022 Apr 5.
To test the failure load and failure mode of a novel implant-crown interface specifically designed for the fabrication of fully personalized, abutment-free monolithic zirconia CAD-CAM crowns compared to conventional implant-abutment interfaces involving prefabricated or centrally manufactured abutments for zirconia CAD-CAM crowns.
Implants (N=48) were divided into groups (n=12) according to different implant-abutment interface designs: (1) internal implant connection with personalized, abutment-free CAD-CAM crowns (Abut-Free-Zr), (2) internal conical connection with customized, centrally manufactured zirconia CAD-CAM abutments (Cen-Abut-Zr), (3) prefabricated titanium base abutments from manufacturer 1 (Ti-Base-1), (4) additional prefabricated titanium base abutments from manufacturer 2 (Ti-Base-2). All specimens were restored with a screw-retained monolithic zirconia CAD-CAM molar crown and subjected to thermomechanical aging (1.200.000 cycles, 49 N, 1.67 Hz, 30° angulation, thermocycling 5-50°C). Static load until failure was applied in a universal testing machine. Failure modes were analyzed descriptively under digital microscope. Mean failure load values were statistically analyzed at a significance level of p<0.05.
All specimens survived thermomechanical aging. The mean failure loads varied between 1332 N (Abut-Free-Zr) and 1601 N (Ti-Base-2), difference being significant between these groups (p<0.05). No differences between the other groups were seen. The predominant failure mode per group was crown fracture above implant connection (Abut-Free-Zr, 75%), abutment fracture below implant neck (Cen-Abut-Zr, 83%), crown fracture leaving an intact abutment (Ti-Base-1/Ti-Base-2 100%).
Implant-crown interface with fully personalized, abutment-free monolithic CAD-CAM zirconia crowns exhibited similar failure loads as conventional implant-abutment interfaces (except group Ti-Base-2) involving CAD-CAM crowns with prefabricated or centrally manufactured abutment.
The new implant connection simplifies the digital workflow for all-ceramic implant reconstructions. The specific design of the implant-crown interface allows the fabrication of fully personalized, abutment-free zirconia implant crowns both in-house and in-laboratory without the need of a prefabricated abutment or central manufacturing.
测试一种专门设计的新型种植体-冠界面的失效负荷和失效模式，该界面专门用于制造全个性化、无基台的整体氧化锆 CAD-CAM 冠，与涉及预制或中央制造氧化锆 CAD-CAM 冠的传统种植体-基台接口进行对比。
根据不同的种植体-基台界面设计，将种植体（N=48）分为四组（n=12）：（1）具有个性化、无基台 CAD-CAM 冠的内部种植体连接（Abut-Free-Zr），（2）具有定制、中央制造氧化锆 CAD-CAM 基台的内部锥形连接（Cen-Abut-Zr），（3）来自制造商 1 的预制钛基台（Ti-Base-1），（4）来自制造商 2 的附加预制钛基台（Ti-Base-2）。所有标本均用螺丝固位的整体氧化锆 CAD-CAM 磨牙冠修复，并进行热机械老化（1200000 次循环，49 N，1.67 Hz，30°角度，5-50°C 热循环）。在万能试验机上施加静态失效负荷。在数字显微镜下对失效模式进行描述性分析。在显著水平 p<0.05 下对平均失效负荷值进行统计分析。
所有标本均通过热机械老化。平均失效负荷值在 1332 N（Abut-Free-Zr）和 1601 N（Ti-Base-2）之间变化，这些组之间的差异具有统计学意义（p<0.05）。其他组之间未见差异。每组的主要失效模式均为种植体连接上方的冠部断裂（Abut-Free-Zr，75%），种植体颈部下方的基台断裂（Cen-Abut-Zr，83%），冠部断裂但基台完整（Ti-Base-1/Ti-Base-2 100%）。
具有全个性化、无基台整体 CAD-CAM 氧化锆冠的种植体-冠界面的失效负荷与涉及预制或中央制造基台的 CAD-CAM 冠的传统种植体-基台界面（除组 Ti-Base-2 外）相似。
新型种植体连接简化了所有陶瓷种植体修复的数字化工作流程。种植体-冠界面的特殊设计允许在内部和实验室中制造全个性化、无基台的氧化锆种植体冠，而无需预制基台或中央制造。
