Moslemion M, Payaminia L, Jalali H, Alikhasi M
Department of Prosthodontics, Faculty of Dentistry, Zanjan University of Medical Sciences, Zanjan, Iran.
Department of Prosthodontics, School of Dentistry, Bushehr University of Medical Sciences, Bushehr, Iran.
Eur J Prosthodont Restor Dent. 2020 Feb 27;28(1):18-27. doi: 10.1922/EJPRD_1962Moslemion10.
Reports concerning the accuracy of intraoral digital impression systems are limited. This study aimed to assess the effects of scan body types and shapes on digital impression accuracy and scanning time in all-on-four restorations.
This in vitro study was conducted with two acrylic maxillary models. Two implant systems with different connection types (internal trilobe and external hexagon connection) were inserted according to the all-on-four design. Scanning was performed using Doowon, NT-Trading, and DESS scan bodies. Changes in implants' positions (ΔR) and angulation (ΔA), and the implants' distance from the reference pin (ΔD) compared with the actual model were determined. Scanning times were also measured and compared.
The effects of implant connections and scan bodies on ΔR and ΔA were significant (p ⟨0.05). Implant angulation could also affect ΔA (p=0.019). ΔD was only affected by scan body (p ⟨0.001). The three scan bodies were significantly different in terms of scanning time (p=0.001).
The results showed that scan body type and shape, and implant connection and angulation could affect digital impression accuracy in all-on-four restorations. For both internal and external connections, the NT-Trading and DESS scan bodies had the shortest and longest scanning times, respectively.
关于口腔内数字印模系统准确性的报告有限。本研究旨在评估扫描体类型和形状对全口四颗种植修复中数字印模准确性和扫描时间的影响。
本体外研究使用了两个丙烯酸上颌模型。根据全口四颗种植设计植入两种具有不同连接类型（内部三叶形和外部六边形连接）的种植系统。使用斗源、NT-Trading和DESS扫描体进行扫描。确定与实际模型相比种植体位置的变化（ΔR）、角度的变化（ΔA）以及种植体与参考针的距离（ΔD）。还测量并比较了扫描时间。
种植体连接和扫描体对ΔR和ΔA的影响具有统计学意义（p＜0.05）。种植体角度也会影响ΔA（p = 0.019）。ΔD仅受扫描体影响（p＜0.001）。三种扫描体在扫描时间方面存在显著差异（p = 0.001）。
结果表明，扫描体类型和形状、种植体连接和角度会影响全口四颗种植修复中的数字印模准确性。对于内部和外部连接，NT-Trading和DESS扫描体的扫描时间分别最短和最长。
