Rasaie Vanya, Abduo Jaafar, Falahchai Mehran
Department of Prosthodontics, Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran.
Department of Prosthodontics, Melbourne Dental School, Melbourne University, Melbourne, Australia.
Eur J Dent. 2022 Jul;16(3):488-499. doi: 10.1055/s-0041-1740298. Epub 2022 Feb 21.
The purpose of this systematic review was to evaluate the clinical and laboratory outcomes of angled screw channel (ASC) restorations and to summarize the influencing factors. An electronic search of the English language literature was performed in four databases and enriched by manual searches. Retrieved studies were screened against the predefined exclusion and inclusion criteria. Eight clinical and seven laboratory studies were eligible for the analysis. The risk of bias for included observational studies was performed using the Newcastle-Ottawa quality assessment scale. Laboratory studies quality assessment method was adapted from previous published systematic reviews. Two clinical studies focused on technical outcomes and the rest reported the biological outcomes of the ASC restorations. Out of the seven laboratory studies, two studies investigated the fracture resistance of ASC restorations, four studies evaluated the reverse torque value of the nonaxially tightened screws, and one study evaluated both variables. The present review revealed that while the performance of ASC restorations is promising in short-term clinical studies, the evidence of their long-term reliability is still lacking. The laboratory studies indicated comparable fracture resistance results of the ASC restorations with the straight screw channel restorations. In addition, factors, such as initial torque value, configuration of the screw driver, screw design, abutment system, and the angulation of screw channel, were shown to influence the screw resistance to loosening.
本系统评价的目的是评估斜向螺钉通道（ASC）修复体的临床和实验室结果，并总结影响因素。在四个数据库中对英文文献进行了电子检索，并通过手工检索加以补充。根据预先定义的排除和纳入标准对检索到的研究进行筛选。八项临床研究和七项实验室研究符合分析要求。使用纽卡斯尔-渥太华质量评估量表对纳入的观察性研究的偏倚风险进行评估。实验室研究质量评估方法改编自先前发表的系统评价。两项临床研究关注技术结果，其余研究报告了ASC修复体的生物学结果。在七项实验室研究中，两项研究调查了ASC修复体的抗折性，四项研究评估了非轴向拧紧螺钉的反向扭矩值，一项研究评估了这两个变量。本评价表明，虽然ASC修复体在短期临床研究中的表现很有前景，但仍缺乏其长期可靠性的证据。实验室研究表明，ASC修复体与直螺钉通道修复体的抗折性结果相当。此外，初始扭矩值、螺丝刀配置、螺钉设计、基台系统和螺钉通道角度等因素被证明会影响螺钉的抗松动性。
