Zhou Yucong, Bi Mengning, Yang Huiquan, He Xiaoya, Wang Xuanyu, Chen Zhihua, Ji Fang
Department of Orthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University, School of Medicine, No.639 Zhizaoju Road, Shanghai, 200011, China.
Sci Rep. 2025 Apr 16;15(1):13049. doi: 10.1038/s41598-025-96920-9.
Despite extensive research on maxillary impacted canines, studies specifically investigating maxillary impacted incisors remain limited. This retrospective study aimed to determine the prevalence of impacted teeth among adolescent orthodontic patients, analyze the imaging characteristics of maxillary impacted incisors, and evaluate factors influencing root development. From a cohort of 2163 underage patients who attended the children malocclusion special clinic between August 2022 and July 2024, individuals with impacted teeth were identified and their clinical data were collected. Subsequently, detailed analyses were conducted on impacted maxillary incisors using high-quality Cone-beam computed tomography (CBCT). There were 157 patients with 205 impacted teeth observed, presenting a prevalence rate of 7.26%. Maxillary canines were the most popular impacted teeth (39.51%), followed by maxillary incisors (30.24%). The tooth dilaceration demonstrated a significant relationship with the three-dimensional (3D) locations of tooth. Impacted teeth situated in low impacted depth (P < 0.05) and those with buccal-lingual (P < 0.05) or vertical (P < 0.01) orientations showed reduced susceptibility to root dilaceration. A positive correlation was observed between the Upper Incisor to Palatal Plane Angle (UI-PP) and both the probability (P < 0.05) and earlier occurrence (P < 0.01) of root dilaceration. The root length of impacted tooth was positively correlated with age (P < 0.05). Besides, the average root length of the impacted central incisors was 1.84 mm shorter than the contralateral. The prevalence of impacted teeth in our orthodontic specialist clinics was 7.26%, and 69.76% of impacted teeth were maxillary anteriors. The development of tooth roots was mainly influenced by age and 3D location. These findings enhance clinicians' understanding of impacted maxillary incisor characteristics and factors affecting the root development. The UI-PP proves to be an effective 3D location evaluation indicator. Early intervention is recommended for impacted teeth lacking sufficient space for root development, which could facilitate root development and minimize the risk of root dilaceration.
尽管对上颌阻生尖牙进行了广泛研究，但专门对上颌阻生切牙进行调查的研究仍然有限。这项回顾性研究旨在确定青少年正畸患者中阻生牙的患病率，分析上颌阻生切牙的影像学特征，并评估影响牙根发育的因素。从2022年8月至2024年7月在儿童错牙合专科门诊就诊的2163名未成年患者队列中，识别出有阻生牙的个体并收集其临床数据。随后，使用高质量锥形束计算机断层扫描（CBCT）对上颌阻生切牙进行详细分析。观察到157例患者有205颗阻生牙，患病率为7.26%。上颌尖牙是最常见的阻生牙（39.51%），其次是上颌切牙（30.24%）。牙折曲与牙齿的三维（3D）位置存在显著关系。位于低阻生深度的阻生牙（P < 0.05）以及颊舌向（P < 0.05）或垂直向（P < 0.01）的阻生牙对牙根折曲的易感性降低。上切牙与腭平面角（UI-PP）与牙根折曲的概率（P < 0.05）和更早发生（P < 0.01）均呈正相关。阻生牙的牙根长度与年龄呈正相关（P < 0.05）。此外，阻生中切牙的平均牙根长度比对侧短1.84mm。我们正畸专科门诊中阻生牙的患病率为7.26%，69.76%的阻生牙为上颌前牙。牙根发育主要受年龄和3D位置的影响。这些发现增强了临床医生对上颌阻生切牙特征以及影响牙根发育因素的理解。UI-PP被证明是一种有效的3D位置评估指标。对于缺乏足够牙根发育空间的阻生牙，建议早期干预，这有助于牙根发育并将牙根折曲的风险降至最低。
