Original scientific paper
Prevalence and Characteristic Features of Mandibular Second Molar Impaction in Chinese-American School Children
Yehoshua Shapira
; Clinical Associate Professor, Department of Orthodontics, The Maurice and Gabriela Goldschleger School of Dental Medicine, Tel Aviv
Tamar Finkelstein
; Instructor, Department of Orthodontics, The Maurice and Gabriela Goldschleger School of Dental Medicine, Tel Aviv University, Israel
Yon H. Lai
; Clinical Professor, Department of Orthodontics, New York University College of Dentistry, New York
Mladen M. Kuftinec
; Professor and Director [retired], Department of Orthodontics, New York University College of Dentistry, New York
Alexander Vardimov
; Associate professor and head, Department of Orthodontics, The Maurice and Gabriela Goldschleger School of Dental Medicine, Tel Aviv
Nir Shpack
; Lecturer, Department of Orthodontics, The Maurice and Gabriela Goldschleger School of Dental Medicine, Tel Aviv University, Israel
Abstract
Objectives: To determine the prevalence and characteristic features of mandibular permanent second molar impaction in a large sample of ethnic Chinese-American orthodontic patients. Materials and methods: Panoramic radiographs of 3000 consecutively orthodontically treated Chinese-American school children aged 11-15 years were studied for mandibular second molar impaction. Their anatomic position and angulation relative to the adjacent teeth were recorded and evaluated. Results: A total of 103 mandibular second molar impactions both unilateral and bilateral were detected in 71 Chinese-American patients with a prevalence of 2.36%. The significant majority of the mandibular second molar impactions (89%) were mesially inclined. Posterior mandibular crowding was detected in most of these impactions and the developing third molars were located along the root of the second molars, giving an impression of an overlap on the twodimensional panoramic radiographs. Conclusions: Chinese-American orthodontic patients present a prevalence rate of 2.36% in mandibular second molar impactions, most of them mesially inclined in posteriorly crowded arches and in close proximity of the developing third molars. A possible mechanism for their impaction is the predominant mesial angulation, possibly caused by the different stages of root development (distal root more developed than the mesial root). The posterior space deficiency appears to be less critical, thus a secondary factor. Early detection and an appropriate orthodontic treatment are recommended for best clinical outcome.
Keywords
Mandible; Molar; Tooth, Impacted; Asian Americans
Hrčak ID:
86880
URI
Publication date:
24.9.2012.
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