不同基台设计和无基台种植体连接方式的整体式氧化锆螺丝固位固定义齿的承载能力

Load-bearing capacity of screw-retained fixed dental prostheses made of monolithic zirconia on different abutment designs and abutment-free implant connection.

作者信息

Schäfer Tobias, Mätzener Kiren J, Jung Ronald E, Özcan Mutlu, Hjerppe Jenni

机构信息

Doctoral Student, Clinic of Reconstructive Dentistry, Center for Dental Medicine, University of Zurich, Plattenstrasse 11, Zurich 8032, Switzerland.

Dental Technician, Clinic of Masticatory Disorders and Dental Biomaterials, Center for Dental Medicine, University of Zurich, Plattenstrasse 11, Zurich 8032, Switzerland.

出版信息

J Dent. 2025 Feb;153:105561. doi: 10.1016/j.jdent.2025.105561. Epub 2025 Jan 6.

DOI:10.1016/j.jdent.2025.105561

PMID:39778736

Abstract

OBJECTIVES

A new abutment-free implant connection allows for direct screwing of FDPs on implants to avoid complications caused by cement rests or screw loosening, which may affect to screw torque and load distribution. The objective of this study was to test the initial (Fi) and final failure (Ff) loads and torque changes of abutment-free monolithic zirconia CAD-CAM fixed dental prostheses (FDPs) compared to titanium FDPs on different abutment designs.

METHODS

Three-unit screw-retained FDPs (n = 50) on two implants (n = 100) were divided into groups (n = 10) based on the implant-abutment connection and material of the supra-structure: (1) abutment-free monolithic CAD-CAM zirconia FDP (Abut-free-Zr), (2) abutment-free veneered titanium FDPs (Abut-free-Ti), (3) monolithic zirconia FDPs with titanium base abutments (Zr-Ti-Base), (4) monolithic zirconia FDPs on multi-unit abutments (Zr-MU), (5) veneered titanium FDP on multi-unit abutments (Ti-MU). All specimens were subjected to thermo-mechanical aging (1'200'000 Cycles, 49 N, 1.67 Hz, 5º to 50º C, dwelling time 120 s). Torque of the screws was measured, and static loading was performed. Data were tested using ANOVA and Tukey's tests (p < 0.05).

RESULTS

After thermo-mechanical aging, all screws showed reduced torque, Ti-MU significantly more reduction compared to Abut-Free-Ti (p = 0.0021). Titanium groups showed significantly lower Fi (N) values (171.4-230 vs 1272-1358,) due to veneering porcelain fractures (p = 0.0001) and significantly higher Ff (N) (2922 -3029 N vs. 1272-1358) values than zirconia groups (p < 0.0001).

CONCLUSIONS

Three-unit abutment-free monolithic zirconia FPDs showed similar failure loads compared to other zirconia groups, while the titanium groups exhibited superior final failure loads. Different abutment designs did not seem to affect the failure loads.

CLINICAL SIGNIFICANCE

The specific design of the novel implant interface allows for the fabrication of implant supported FDPs with personalized design directly on implant level without abutments. The monolithic zirconia FDPs on abutment-free implant connection can be used with good confidence since they exhibit similar mechanical stability as monolithic zirconia FDPs on titanium-base or multi-unit abutments.

摘要

目的

一种新型无基台种植体连接方式允许将固定义齿（FDPs）直接拧在种植体上，以避免由粘结剂残留或螺钉松动引起的并发症，这些并发症可能会影响螺钉扭矩和负荷分布。本研究的目的是测试与不同基台设计的钛制固定义齿相比，无基台整体式氧化锆计算机辅助设计与制造（CAD-CAM）固定义齿（FDPs）的初始（Fi）和最终破坏（Ff）负荷以及扭矩变化。

方法

将两颗种植体（n = 100）上的三单位螺钉固位固定义齿（n = 50）根据种植体-基台连接和上部结构材料分为几组（n = 10）：（1）无基台整体式CAD-CAM氧化锆固定义齿（无基台-锆），（2）无基台烤瓷熔附钛固定义齿（无基台-钛），（3）带有钛基台的整体式氧化锆固定义齿（锆-钛基），（4）多单位基台上的整体式氧化锆固定义齿（锆-多单位），（5）多单位基台上的烤瓷熔附钛固定义齿（钛-多单位）。所有标本均进行热机械老化（1200000次循环，49 N，1.67 Hz，5℃至50℃，停留时间120 s）。测量螺钉扭矩并进行静态加载。数据采用方差分析和Tukey检验（p < 0.05）。

结果

热机械老化后，所有螺钉的扭矩均降低，钛-多单位组与无基台-钛组相比扭矩降低更显著（p = 0.0021）。由于烤瓷层骨折，钛组的初始负荷（N）值显著较低（171.4 - 230 vs 1272 - 1358）（p = 0.0001），且最终破坏负荷（N）值显著高于氧化锆组（2922 - 3029 N vs. 1272 - 1358）（p < 0.0001）。