Abdulghani Ehab A, Alhammadi Maged Sultan, Al-Sosowa Abeer A, Almashraqi Abeer A, Sharhan Hasan M, Al-Fakeh Hanan, Cao BaoCheng
Department of Orthodontics and Dentofacial Orthopedics, College of Dentistry, Lanzhou University, Lanzhou, China.
Division of Orthodonticsand Dentofacial Orthopedics, Department of Preventive Dental Sciences, College of Dentistry, Jazan University, Jazan, Saudi Arabia.
Clin Oral Investig. 2022 Jul;26(7):4905-4915. doi: 10.1007/s00784-022-04458-1. Epub 2022 Mar 20.
Posterior teeth intrusion is one of the best treatment options for treatment of skeletal open bite in adults; the surrounding anatomical landmarks are one of the restraining factors. This study aimed to assess the vertical relationship between the maxillary posterior teeth (MPT) and the maxillary sinus floor (MSF) in different facial growth patterns in the Chinese adult population.
Cone beam computed tomography images of 298 patients, 145 males and 153 females aged between 20 and 45 years, were analyzed. Based on Jarabak ratio and the mandibular plane inclination, the sample was categorized into 94 hyperdivergent, 102 hypodivergent, and 102 normodivergent facial patterns subjects. The vertical relationship between the root-apex distances were classified as favorable, indicating no contact (type 1), or unfavorable, indicating roots in contact (type 2) for the posterior teeth intrusion. The relationship in the unfavorable group was subdivided into three subgroups (T2C, T2LC, and T2P). Comparative statistical tests were done related to age, gender, tooth side, and type of multiplanar view (sagittal and coronal). The significant level was set to be P < 0.05.
There was a statistically significant difference in the mean distance between both genders in the hyperdivergent group (P < 0.001). The measured distance increased with age in all tooth roots (P < 0.001). In both sagittal and coronal views, the most frequent root scores were type 1 and type 2p (54.2%, 27.5%) and (55.1%, 21.4%), respectively. The hyperdivergent group demonstrated a higher prevalence of type 2P (31.6% and 25.5%), whereas the hypodivergent group showed a lower prevalence (25.1% and 19.2%); furthermore, the second molar's mesiobuccal root in hyperdivergent patients showed the closest distance to the maxillary sinus in sagittal and coronal views, 0.3 ± 3.7 and 0.4 ± 3.1 mm, respectively.
Maxillary molars of hyperdivergent patients have the highest possible risk of root resorption due to the possible risk of cortical bone encroachment, while hypodivergent patients have the least possible risk.
Analysis of apex-sinus distances can be of great help for safe posterior teeth intrusion and providing correct and adequate treatment.
后牙压低是治疗成人骨性开颌的最佳治疗选择之一；周围的解剖标志是限制因素之一。本研究旨在评估中国成年人群不同面部生长型中上颌后牙（MPT）与上颌窦底（MSF）之间的垂直关系。
分析了298例年龄在20至45岁之间的患者的锥形束计算机断层扫描图像，其中男性145例，女性153例。根据贾拉巴克比率和下颌平面倾斜度，将样本分为94例高角型、102例低角型和102例均角型面部模式受试者。后牙压低时，根尖距离的垂直关系分为有利（即无接触，1型）或不利（即牙根接触，2型）。不利组的关系再细分为三个亚组（T2C、T2LC和T2P）。进行了与年龄、性别、牙位侧别和多平面视图类型（矢状面和冠状面）相关的比较统计检验。显著性水平设定为P<0.05。
高角型组中，两性之间的平均距离存在统计学显著差异（P<0.001）。所有牙根的测量距离均随年龄增加（P<0.001）。在矢状面和冠状面视图中，最常见的牙根评分分别为1型和2p型（54.2%，27.5%）和（55.1%，21.4%）。高角型组2P型的患病率较高（31.6%和25.5%），而低角型组的患病率较低（25.1%和19.2%）；此外，在矢状面和冠状面视图中，高角型患者的第二磨牙近中颊根与上颌窦的距离最近，分别为0.3±3.7和0.4±3.1mm。
由于存在皮质骨侵犯的可能风险，高角型患者的上颌磨牙牙根吸收风险最高，而低角型患者的风险最低。
根尖-窦距离分析有助于安全地压低后牙并提供正确且充分的治疗。
