Ramasamy Padmanathan, Sabrish Sharanya, Pattabiraman Vinod, Shivamurthy Prashantha Govinakovi, Sagarkar Roshan, Mathew Silju
Department of Orthodontics, Faculty of Dental Sciences, M S Ramaiah University of Applied Sciences, Bengaluru, Karnataka, India.
Consultant Orthodontist, Private Practitioner, Bengaluru, Karnataka, India.
Indian J Dent Res. 2022 Jul-Sep;33(3):277-281. doi: 10.4103/ijdr.ijdr_1201_21.
Mandibular buccal shelf (MBS) offers good quality and quantity of bone for orthodontic bone screw (OBS) insertion. Despite several reports of treated patients, there are numerous variables in selecting the exact placement site for OBS placement in the MBS. There are also anatomical variations in this area which must be considered.
This study aims to measure and compare the MBS bone characteristics for OBS placement using cone beam computed tomography (CBCT) between two different facial types.
Eighty CBCT samples were collected (40 samples of group A horizontal growers and 40 of group B vertical growers). Each CBCT image was reconstructed and oriented with CS 3D CBCT software. The cortical bone thickness, the slope of the MBS, and buccolingual inclination of mandibular second molar were measured and analysed.
Cortical bone thickness among horizontal growers was 5.23 ± 0.58 mm and among vertical growers was 4.85 ± 0.37 mm. The slope of MBS among horizontal growers was 60.83 ± 6.15 degrees and among vertical growers was 66.75 ± 6.27 degrees. In both the parameters there was a statistically significant difference between the groups. There was no significant difference between the groups for the buccolingual inclination of 2 molar.
Increased cortical bone thickness and the flatter slope of MBS at the 2 molar region allows for easier placement of OBS in horizontal growers than in vertical growers.
下颌颊侧骨板（MBS）为正畸骨钉（OBS）植入提供了优质且充足的骨量。尽管有一些关于已治疗患者的报告，但在MBS中选择OBS的确切植入位置时存在众多变量。该区域还存在解剖变异，必须予以考虑。
本研究旨在使用锥形束计算机断层扫描（CBCT）测量和比较两种不同面型患者用于OBS植入的MBS骨特征。
收集了80例CBCT样本（A组水平生长型患者40例，B组垂直生长型患者40例）。使用CS 3D CBCT软件对每个CBCT图像进行重建和定向。测量并分析皮质骨厚度、MBS的斜率以及下颌第二磨牙的颊舌向倾斜度。
水平生长型患者的皮质骨厚度为5.23±0.58毫米，垂直生长型患者为4.85±0.37毫米。水平生长型患者MBS的斜率为60.83±6.15度，垂直生长型患者为66.75±6.27度。在这两个参数上，两组之间存在统计学显著差异。两组下颌第二磨牙的颊舌向倾斜度无显著差异。
与垂直生长型患者相比，水平生长型患者在第二磨牙区域皮质骨厚度增加且MBS斜率更平缓，这使得OBS更容易植入。
