Alnasser Abdullah H, Wadhwani Chandur P K, Alsarraf Esra Y, Kattadiyil Mathew T, Lozada Jaime
Fellow, Advanced Digital Prosthodontics and Implant Dentistry Program, Loma Linda University, Loma Linda, Calif; Teaching Assistant, Department of Prosthodontics, School of Dentistry, Prince Sattam bin Abdulaziz University, Al-Kharj, Saudi Arabia.
Adjunct Assistant Professor, Advanced Education Program in Prosthodontics, Loma Linda University, Loma Linda, Calif.
J Prosthet Dent. 2024 Dec;132(6):1310.e1-1310.e8. doi: 10.1016/j.prosdent.2023.05.018. Epub 2023 Jul 8.
STATEMENT OF PROBLEM: Implant abutment screw loosening is the most common prosthetic complication of implant-supported single crowns. However, few studies have objectively evaluated the effectiveness of different tightening protocols on reverse tightening values (RTVs).
The purpose of this in vitro study was to determine the optimal tightening protocol for implant abutment screws with different screw materials.
Sixty implants from 2 implant systems (Keystone and Nobel Biocare) with different definitive screw materials were selected. One group used diamond-like carbon (DLC) coated screws (DLC Group), and the other used titanium nitride (TiN) screws (TiN Group). Each group consisted of 30 implants. The implants in each group were distributed randomly into 3 subgroups (n=10). The implants from both manufacturers were mounted in resin blocks by following a clinical component connection protocol: a cover screw was placed, then an impression coping, and finally an original manufacturer prefabricated abutment. The abutment screws were tightened to the manufacturer's recommended tightening value using 3 different protocols: tighten the screw once (1T); tighten the abutment screw to the recommended tightening value, wait 10 minutes, and then retighten (2T); and tighten the abutment screw to the recommended tightening value, countertighten, tighten, countertighten, and then tighten (3TC). RTVs were measured after 3 hours. The Shapiro-Wilk test was performed to test for normal distribution of the data. The Kruskal-Wallis test was applied to each system's group that was not normally distributed (P<.05). Where differences existed, a post hoc analysis using the Dwass-Steel-Critchlow-Flinger (DSCF) pairwise comparisons test was conducted.
No significant differences were found among the 3 different tightening groups in the TiN group (P>.05). However, significant differences were found among the 3 different tightening protocols in the DLC group (P<.05).
Abutment screw systems from different manufacturers behave differently with respect to how they are tightened. For the TiN screw group, statistically similar RTVs were found for the 3 tightening protocols. The most efficient tightening protocol for the DLC-coated screw was the 3TC-DLC.
种植体基台螺丝松动是种植支持单冠修复中最常见的修复并发症。然而，很少有研究客观评估不同拧紧方案对反向拧紧值（RTV）的有效性。
本体外研究的目的是确定不同螺丝材料的种植体基台螺丝的最佳拧紧方案。
从2种种植系统（Keystone和Nobel Biocare）中选择60颗具有不同最终螺丝材料的种植体。一组使用类金刚石碳（DLC）涂层螺丝（DLC组），另一组使用氮化钛（TiN）螺丝（TiN组）。每组由30颗种植体组成。每组中的种植体随机分为3个亚组（n = 10）。按照临床部件连接方案将两个制造商的种植体安装在树脂块中：先放置覆盖螺丝，然后放置印模帽，最后放置原始制造商预制的基台。使用3种不同方案将基台螺丝拧紧至制造商推荐的拧紧值：一次性拧紧螺丝（1T）；将基台螺丝拧紧至推荐拧紧值，等待10分钟，然后重新拧紧（2T）；将基台螺丝拧紧至推荐拧紧值，反向拧紧、拧紧、反向拧紧，然后再拧紧（3TC）。3小时后测量RTV。进行Shapiro-Wilk检验以测试数据的正态分布。对每个系统中不呈正态分布的组应用Kruskal-Wallis检验（P <.05）。若存在差异，则使用德瓦斯-斯蒂尔-克里奇洛-弗林格（DSCF）成对比较检验进行事后分析。
TiN组中3种不同拧紧组之间未发现显著差异（P >.05）。然而，DLC组中3种不同拧紧方案之间发现了显著差异（P <.05）。
不同制造商的基台螺丝系统在拧紧方式上表现不同。对于TiN螺丝组，3种拧紧方案的RTV在统计学上相似。DLC涂层螺丝最有效的拧紧方案是3TC-DLC。
