Kosumarl Werinpimol, Patanaporn Virush, Jotikasthira Dhirawat, Janhom Apirum
Dental Division, Suan Phueng Hospital, Ratchaburi, Thailand.
Department of Orthodontics and Pediatric Dentistry, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand.
Imaging Sci Dent. 2017 Sep;47(3):157-164. doi: 10.5624/isd.2017.47.3.157. Epub 2017 Sep 21.
This study determined and compared the distances from the maxillary root apices of posterior teeth to the floor of the maxillary sinus, or maxillary sinus distances (MSDs), and the distances from the mandibular root apices of the posterior teeth to the mandibular canal, or mandibular canal distances (MCDs), in Thai subjects with skeletal open bite and skeletal normal bite.
Pretreatment cone-beam computed tomography (CBCT) images were obtained from 30 Thai orthodontic patients (15 patients with skeletal normal bite and 15 with skeletal open bite) whose ages ranged from 14 to 28 years. The CBCT images of the patients were processed and measured using the Romexis Viewer program. The MSDs and MCDs from the root apices of the maxillary and mandibular second premolar, first molar, and second molar to the maxillary sinus floor or the mandibular canal were measured perpendicularly to the occlusal plane. The Student t test was used for comparisons between the 2 groups.
The greatest mean MSDs were from the root apex of the second premolars in both groups, whereas the least mean MSDs were from the mesiobuccal root apex of the second molars. The greatest mean MCDs were from the mesial root apex of the first molars, whereas the least mean MCDs were from the distal root apex of the second molars.
There were no differences in the mean MSDs or the mean MCDs between the skeletal normal bite group and the skeletal open bite group.
本研究测定并比较了泰国骨骼性开颌和骨骼正常咬合受试者后牙上颌根尖至上颌窦底的距离,即上颌窦距离(MSD),以及后牙下颌根尖至下颌管的距离,即下颌管距离(MCD)。
从30名年龄在14至28岁的泰国正畸患者(15名骨骼正常咬合患者和15名骨骼性开颌患者)获取治疗前锥形束计算机断层扫描(CBCT)图像。使用Romexis Viewer程序对患者的CBCT图像进行处理和测量。垂直于咬合平面测量上颌和下颌第二前磨牙、第一磨牙及第二磨牙根尖至上颌窦底或下颌管的MSD和MCD。采用独立样本t检验对两组进行比较。
两组中最大平均MSD均来自第二前磨牙根尖,而最小平均MSD来自第二磨牙近中颊根尖。最大平均MCD来自第一磨牙近中根尖,而最小平均MCD来自第二磨牙远中根尖。
骨骼正常咬合组与骨骼性开颌组之间的平均MSD或平均MCD无差异。