Morphological difference of symphysis according to various skeletal types using cone-beam computed tomography

안면골격 유형에 따른 하악 전치 치조골의 형태 차이: Cone-beam CT를 이용한 정량적 평가

  • Kwon, Hyun-Jin (Graduate School of Clinical Dentistry, Ewha Womans University) ;
  • Chun, Youn-Sic (Graduate School of Clinical Dentistry, Ewha Womans University) ;
  • Kim, Min-Ji (Graduate School of Clinical Dentistry, Ewha Womans University)
  • 권현진 (이화여자대학교 임상치의학대학원) ;
  • 전윤식 (이화여자대학교 임상치의학대학원) ;
  • 김민지 (이화여자대학교 임상치의학대학원)
  • Received : 2014.06.23
  • Accepted : 2014.08.15
  • Published : 2014.09.30


Purpose: The aim of this study was to investigate differences between the morphology of the mandibular symphysis and four facial skeletal types. Materials and Methods: 40 cone-beam computed tomographies were selected and classified in to 4 groups according to their vertical and anterior-posterior skeletal patterns. The bone volume ($mm^3$) of the symphysis, the cross sectional area corresponding to the 4 mandibular incisors' axis: the cross sectional area of total bone ($mm^2$), the area of the cancellous bone ($mm^2$) and the thickness (mm) of labial and lingual alveolar bone at 2 mm, 3 mm under the cemento-enamel junction (CEJ) were measured. General linear model (GLM), Kruskal-Wallis test and Tukey honestly significant difference (HSD) test were subsequently used for statistical analysis. Results: The lingual cortical bone thickness of the lateral incisors at 2, 3 mm under CEJ was greater in the Class I low angle group than the other 3 groups (P < 0.05). There were no statistically significant differences in the volume of the mandibular incisor bony support, cross-sectional area of total bone and cancellous bone at the mandibular incisor' axis. Conclusion: Patients in Class I, low angle group have a thicker lingual mandibular symphysis than Class I, high angle patients.


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