M A Momin1, K Matsumoto, K Ejima, R Asaumi, T Kawai, Y Arai, K Honda, T Yosue. 1. Department of Oral and Maxillofacial Radiology, The Nippon Dental University School of Life Dentistry at Tokyo, 1-9-20, Fujimi, Chiyoda-ku, Tokyo 102-8159, Japan. drmomin.orad@hotmail.com
Abstract
PURPOSE: To determine the width and morphology of the mandible in the impacted third molar region, and to identify the location of the mandibular canal prior to planning impacted third molar operations. METHODS: Cone beam computed tomography (CBCT) data of 87 mandibular third molars from 62 Japanese patients were analyzed in this study. The width of the lingual cortical bone and apex-canal distance were measured from cross-sectional images in which the cortical bone was thinnest at the lingual side in the third molar region. Images were used for measuring the space (distance between the inner border of the lingual cortical bone and outer surface of the third molar root), apex-canal distance (distance from the root of the third molar tooth to the superior border of the inferior alveolar canal) and the cortical bone (width between the inner and outer borders of the lingual cortical bone). RESULTS: The means of the space, apex-canal distance and lingual cortical width were 0.31, 1.99, and 0.68 mm, respectively. Impacted third molar teeth (types A-C) were observed at the following frequencies: type A (angular) 37 %; type B (horizontal), 42 %; type C (vertical), 21 %. The morphology of the mandible at the third molar region (types D-F) was observed as: type D (round), 49 %; type E (lingual extended), 18 %; and type F (lingual concave), 32 %. CONCLUSIONS: The width and morphology of the mandible with impacted teeth and the location of the mandibular canal at the third molar region could be clearly determined using cross-sectional CBCT images.
PURPOSE: To determine the width and morphology of the mandible in the impacted third molar region, and to identify the location of the mandibular canal prior to planning impacted third molar operations. METHODS: Cone beam computed tomography (CBCT) data of 87 mandibular third molars from 62 Japanese patients were analyzed in this study. The width of the lingual cortical bone and apex-canal distance were measured from cross-sectional images in which the cortical bone was thinnest at the lingual side in the third molar region. Images were used for measuring the space (distance between the inner border of the lingual cortical bone and outer surface of the third molar root), apex-canal distance (distance from the root of the third molar tooth to the superior border of the inferior alveolar canal) and the cortical bone (width between the inner and outer borders of the lingual cortical bone). RESULTS: The means of the space, apex-canal distance and lingual cortical width were 0.31, 1.99, and 0.68 mm, respectively. Impacted third molar teeth (types A-C) were observed at the following frequencies: type A (angular) 37 %; type B (horizontal), 42 %; type C (vertical), 21 %. The morphology of the mandible at the third molar region (types D-F) was observed as: type D (round), 49 %; type E (lingual extended), 18 %; and type F (lingual concave), 32 %. CONCLUSIONS: The width and morphology of the mandible with impacted teeth and the location of the mandibular canal at the third molar region could be clearly determined using cross-sectional CBCT images.
Authors: Oana Bida Honey; William Charles Scarfe; Michael J Hilgers; Kathleen Klueber; Anibal M Silveira; Bruce S Haskell; Allan G Farman Journal: Am J Orthod Dentofacial Orthop Date: 2007-10 Impact factor: 2.650
Authors: Anni Suomalainen; Irja Ventä; Mika Mattila; Lauri Turtola; Tapio Vehmas; Jaakko S Peltola Journal: Oral Surg Oral Med Oral Pathol Oral Radiol Endod Date: 2010-02
Authors: H Ghaeminia; G J Meijer; A Soehardi; W A Borstlap; J Mulder; S J Bergé Journal: Int J Oral Maxillofac Surg Date: 2009-07-28 Impact factor: 2.789