Assistant Professor, Department of Prosthodontics, Faculty of Dentistry, Erciyes University, Kayseri, Turkey.
Professor, Department of Prosthodontics, Faculty of Dentistry, Erciyes University, Kayseri, Turkey.
J Prosthet Dent. 2021 Mar;125(3):500.e1-500.e9. doi: 10.1016/j.prosdent.2020.09.028. Epub 2020 Nov 24.
Whether preparation of an implant abutment decreases the stability of the abutment screw joint is unclear.
The purpose of this in vitro study was to evaluate the effect of the abutment preparation in laboratory conditions on the reverse torque value (RTV) of the abutment screw.
Sixty implants, implant analogs, and abutments obtained from 2 different manufacturers were used in the present study and divided into 2 groups (groups B and N) according to the manufacturer. Each group was then divided into 3 subgroups (n=10) according to the remaining wall thickness (control, 0.4 mm, 0.6 mm). All abutments were tightened to analogs with 15 Ncm, and standardized preparation was made with a custom-designed copy-milling system. All abutments were tightened to the implants with 30 Ncm, and then, the abutment screws were removed and RTVs were recorded. Subgroups were analyzed by using 1-way ANOVA (α=.05), and the independent-sample t test was used to compare groups. Relationships between categorical variables were analyzed by chi-square tests. One abutment screw from each subgroup was randomly selected and analyzed by using a scanning electron microscope.
A statistically significant difference was found between RTVs of different manufacturers (group B=28.2 ±1.2 Ncm, group N=25.9 ±1.4 Ncm; P<.005). In group N, there was a significant difference among subgroups, control (26.7 ±1.4 Ncm), and 0.6-mm wall thickness (24.8 ±0.8 Ncm) (P<.05). A statistically significant relationship was found between preparation and RTV for the NucleOSS only (P<.05) and between manufacturer and RTV (P<.001). Scanning electron microscopy evaluations identified different screw head and thread designs.
The abutment screw joint stability of the BioHorizons implant was not affected by abutment preparation.
目前尚不清楚制备种植体基台是否会降低基台螺丝连接的稳定性。
本体外研究的目的是评估在实验室条件下制备基台对接合螺丝的反扭矩值（RTV）的影响。
本研究使用了来自 2 个不同制造商的 60 个种植体、种植体模拟体和基台，并根据制造商将其分为 2 组（组 B 和组 N）。然后，根据剩余壁厚度（对照组，0.4mm，0.6mm）将每组分为 3 个子组（n=10）。所有基台均用 15Ncm 拧紧到模拟体上，并使用定制设计的复制铣削系统进行标准化制备。所有基台均用 30Ncm 拧紧到种植体上，然后拆卸基台螺丝并记录 RTV 值。使用单向方差分析（α=.05）对亚组进行分析，使用独立样本 t 检验比较组间差异。使用卡方检验分析分类变量之间的关系。从每个子组中随机选择一个基台螺丝，并使用扫描电子显微镜进行分析。
不同制造商的 RTV 值存在显著差异（组 B=28.2±1.2Ncm，组 N=25.9±1.4Ncm；P<.005）。在组 N 中，对照组（26.7±1.4Ncm）和 0.6mm 壁厚组（24.8±0.8Ncm）之间存在显著差异（P<.05）。仅 NucleOSS 存在制备与 RTV 之间的统计学显著关系（P<.05），以及制造商与 RTV 之间的统计学显著关系（P<.001）。扫描电子显微镜评估确定了不同的螺丝头和螺纹设计。
BioHorizons 种植体的基台螺丝连接稳定性不受基台制备的影响。
