The regression formulae of estimating the auditory meatus angle of 100 cases(200 sides)of Chinese adult crania were studied.The coefficient of correlation between the average figure of each cranialmeasurement and auditory meatus angle was calculated.The coefficient of correla-tion between the maximum cranial breadth and auditory meatus angle is(-0.881)which denotes a rather high degree of negative correlation.It is concluded that themaximum cranial breadth is in inverse proportion to the size of the auditory meatusangle,that is,the wider the breadth,the smaller the angle.On the contrary,thecoefficient of correlation between the auricular height and auditory meatus angle is0.311 which exhibits a positive correlation,that is,the higher the height,the largerthe angle and vice versa.The mean degree of the auditory meatus angle is 21?(more exactly 21.21?)in Chinese,and the sex and side differences are notsignificant.This paper calculated the regression formulae of the estimation of auditorymeatus angle from the maximum cranial breadth and the auricular height.Thecoefficient of regression of the former is(-3.85?0.397),t_b=9.695,P

Mandibular buccal bifurcation cyst is a rare inflammatory odontogenic cyst. We reported two cases who complained of painful swelling of extraoral soft tissue. Intraoral examination revealed the partially erupted mandibular first molar. Cone beam computed tomography showed a well-defined cystic lesion surrounding the first molar. Histopathologic images showed the cyst wall was infiltrated by a large number of plasma cells, neutrophils and eosinophils, and lined with a thin layer of non-keratinized stratified squamous epithelium. Finally, the two patients were diagnosed as mandibular buccal bifurcation cyst and treated with cyst enucleation and curettage.