Memon Sarwat, Fida Mubassar
Section of Dentistry, Department of Surgery, The Aga Khan University Hospital, Karachi.
J Coll Physicians Surg Pak. 2014 Aug;24(8):597-9.
Transposition is a dental anomaly characterized by the exchange of position between two adjacent teeth, especially in relation to their roots, or development and eruption of a tooth in a position normally occupied by a nonadjacent tooth. Transposition of the maxillary canine and first premolar has a low prevalence in the population and it primarily affects maxillary canines and premolars. The aetiology of the transposition remains unclear, although it has been associated with genetic factors. It may also be related to a combination of localised factors such as malformation of adjacent teeth, tooth agenesis, retention of the deciduous canine and a history of local trauma. If uncorrected, the results are often both functionally and esthetically unsatisfactory. This case report presents treatment of a female patient with complete bilateral transposition of maxillary canine and premolar. The patient was treated orthodontically with non-extraction fixed mechanotherapy by simulation of maxillary first premolar as canine bilaterally.
牙齿易位是一种牙颌面畸形,其特征是相邻两颗牙齿的位置发生交换,特别是牙根的位置,或者一颗牙齿在通常由非相邻牙齿占据的位置上发育和萌出。上颌尖牙和第一前磨牙易位在人群中的患病率较低,主要影响上颌尖牙和前磨牙。虽然牙齿易位与遗传因素有关,但其病因仍不清楚。它也可能与局部因素的组合有关,如相邻牙齿畸形、牙齿缺失、乳牙滞留和局部创伤史。如果不进行矫正,其结果在功能和美观上往往都不尽人意。本病例报告介绍了一名女性患者上颌尖牙和前磨牙完全双侧易位的治疗情况。通过双侧模拟上颌第一前磨牙为尖牙,采用非拔牙固定机械疗法对该患者进行正畸治疗。