Al-Alawi Hassan, Al-Nazhan Saad, Al-Maflehi Nassr, Aldosimani Mazen A, Zahid Mohammed Nabil, Shihabi Ghadeer N
Dental Department, Ministry of Health Endodontist, Huraymala General Hospital, Riyadh, Saudi Arabia.
Department of Restorative Dentistry-Endodontics, College of Dentistry, Riyadh Elm University, Riyadh, Saudi Arabia.
Restor Dent Endod. 2019 Nov 14;45(1):e1. doi: 10.5395/rde.2020.45.e1. eCollection 2020 Feb.
The purpose of this study was to determine the incidence of radix molaris (RM) (entomolaris and paramolaris) in the mandibular first permanent molars of a sample Saudi Arabian subpopulation using cone-beam computed tomography (CBCT).
A total of 884 CBCT images of 427 male and 457 female Saudi citizens (age 16 to 70 years) were collected from the radiology department archives of 4 dental centers. A total of 450 CBCT images of 741 mature mandibular first molars that met the inclusion criteria were reviewed. The images were viewed at high resolution by 3 examiners and were analyzed with Planmeca Romexis software (version 5.2).
Thirty-three (4.5%) mandibular first permanent molars had RM, mostly on the distal side. The incidence of radix entomolaris (EM) was 4.3%, while that of radix paramolaris was 0.3%. The RM roots had one canal and occurred more unilaterally. No significant difference in root configuration was found between males and females ( > 0.05). Types I and III EM root canal configurations were most common, while type B was the only RP configuration observed.
The incidence of RM in the mandibular first molars of this Saudi subpopulation was 4.5%. Identification of the supernumerary root can avoid missing the canal associated with the root during root canal treatment.
本研究的目的是使用锥形束计算机断层扫描（CBCT）确定沙特阿拉伯一个亚人群样本的下颌第一恒磨牙中磨牙根（RM）（远中磨牙根和副磨牙根）的发生率。
从4个牙科中心的放射科档案中收集了427名男性和457名女性沙特公民（年龄16至70岁）的884张CBCT图像。对符合纳入标准的741颗成熟下颌第一磨牙的450张CBCT图像进行了回顾。由3名检查人员以高分辨率查看图像，并使用Planmeca Romexis软件（版本5.2）进行分析。
33颗（4.5%）下颌第一恒磨牙有RM，大多位于远中侧。远中磨牙根（EM）的发生率为4.3%，而副磨牙根的发生率为0.3%。RM根有一个根管，且多为单侧出现。男性和女性在牙根形态上未发现显著差异（>0.05）。I型和III型EM根管形态最为常见，而B型是观察到的唯一RP形态。
该沙特亚人群下颌第一磨牙中RM的发生率为4.5%。识别额外牙根可避免在根管治疗过程中遗漏与该牙根相关的根管。
