Kim Min Keun, Ham Min Ji, Kim Won Rae, Kim Hyung Giun, Kwon Kwang Jun, Kim Seong Gon, Park Young Wook
Department of Oral and Maxillofacial Surgery, College of Dentistry, Gangneung-Wonju National University, Gangneung, 25457, Republic of Korea.
Functional Materials and Components R&D Group, Korea Institute of Industrial Technology, Gangneung, 25440, Republic of Korea.
Maxillofac Plast Reconstr Surg. 2023 Jan 26;45(1):8. doi: 10.1186/s40902-023-00375-9.
This study aimed to analyze the accuracy of the output of three-dimensional (3D) customized surgical guides and titanium implants in a rabbit model, and of mandibulectomy, reconstructive surgery, and surgical outcome; additionally, the correlation between surgical accuracy and surgical outcomes, including the differences in surgical outcome according to surgical accuracy, was analyzed.
The output of implants was accurately implemented within the error range (- 0.03-0.03 mm), and the surgical accuracy varied depending on the measured area (range - 0.4-1.1 mm). Regarding surgical outcomes, angle between the mandibular lower borders showed the most sensitive results and distance between the lingual cusps of the first molars represented the most accurate outcomes. A significant correlation was noted between surgical accuracy in the anteroposterior length of the upper borders pre- and postoperatively and the angle between the mandibular lower borders (regression coefficient = 0.491, p = 0.028). In the group wherein surgery was performed more accurately, the angle between the mandibular lower borders was reproduced more accurately (p = 0.021). A selective laser melting machine accurately printed the implants as designed. Considering the positive correlation among surgical accuracy in the mandibular upper borders, angle between the mandibular lower borders, and more accurately reproduced angle between the mandibular lower borders, the angle between the mandibular lower borders is considered a good indicator for evaluating the outcomes of reconstructive surgery.
To reduce errors in surgical outcomes, it is necessary to devise a positioner for the surgical guide and design a 3D surgical guide to constantly maintain the direction of bone resection. A fixed area considering the concept of three-point fixation should be selected for stable positioning of the implant; in some cases, bilateral cortical bone fixation should be considered. The angle between the mandibular lower borders is a sensitive indicator for evaluating the outcomes of reconstructive surgery.
本研究旨在分析三维（3D）定制手术导板和钛植入物在兔模型中的输出精度，以及下颌骨切除术、重建手术和手术结果的精度；此外，还分析了手术精度与手术结果之间的相关性，包括根据手术精度的手术结果差异。
植入物的输出在误差范围内（-0.03 - 0.03毫米）准确实现，手术精度因测量区域而异（范围为-0.4 - 1.1毫米）。关于手术结果，下颌下缘之间的角度显示出最敏感的结果，第一磨牙舌尖之间的距离代表最准确的结果。术前和术后上缘前后长度的手术精度与下颌下缘之间的角度之间存在显著相关性（回归系数 = 0.491，p = 0.028）。在手术执行更精确的组中，下颌下缘之间的角度再现得更准确（p = 0.021）。选择性激光熔化机按设计准确打印植入物。考虑到下颌上缘的手术精度、下颌下缘之间的角度以及下颌下缘之间更准确再现的角度之间的正相关，下颌下缘之间的角度被认为是评估重建手术结果的良好指标。
为减少手术结果中的误差，有必要设计手术导板的定位器并设计3D手术导板以持续保持骨切除方向。应选择考虑三点固定概念的固定区域以稳定植入物定位；在某些情况下，应考虑双侧皮质骨固定。下颌下缘之间的角度是评估重建手术结果的敏感指标。
