Paris M, Trunde F, Bossard D, Farges J C, Coudert J L
Service de Consultations et de Traitements Dentaires, Hospices Civils, place Déperet, Lyon.
J Radiol. 2010 Jun;91(6):707-11. doi: 10.1016/s0221-0363(10)70101-3.
The etiology of unerupted teeth often is difficult to establish. It may relate to abnormal orientation of the tooth bud, an anatomical obstacle, pathology of the dental sac or ankylosis. The ankylosis process and diagnosis are analyzed in this clinical series. Ankylosis and its underlying physiological process are abundantly described in the literature. Nonetheless, diagnosis remains difficult to achieve. Clinical evaluation and complementary radiographic techniques such as dental radiographs and orthopantomogram are considered by some authors as poorly reliable. These clinical examinations based on a series of subjective criteria cannot be performed on unerupted teeth. In a series of patients with unerupted or retained teeth of undetermined etiology or with traction failure, 15 were diagnosed with ankylosis. The diagnosis of ankylosis could not be achieved based on clinical or radiographic evaluation and required CT imaging. Source images along with tridimensional reconstructed images were evaluated using the MVS software (Hospices Civils of Lyon). The radicular volume involved by ankylosis could be measured and its exact location on the tooth could be demonstrated. This imaging technique with tridimensional reconstruction provided positive diagnosis of ankylosis.
阻生牙的病因通常很难确定。它可能与牙胚的异常定位、解剖学障碍、牙囊病变或牙根粘连有关。本临床系列分析了牙根粘连的过程及诊断。牙根粘连及其潜在的生理过程在文献中有大量描述。尽管如此，诊断仍然很难实现。一些作者认为，临床评估以及牙科X光片和曲面断层片等辅助影像学技术的可靠性较差。这些基于一系列主观标准的临床检查无法用于阻生牙。在一系列病因不明的阻生牙或滞留牙患者或牵引失败的患者中，有15例被诊断为牙根粘连。牙根粘连的诊断无法基于临床或影像学评估得出，需要CT成像。使用MVS软件（里昂市立医院）对源图像以及三维重建图像进行评估。可以测量牙根粘连所涉及的牙根体积，并能显示其在牙齿上的确切位置。这种三维重建成像技术为牙根粘连提供了阳性诊断。
