Forms and functions of structures are two interrelated things in the human body. Bones adapt to functional forces according to Wolf's law. Our jaw bones also follow the same law. Facial divergence has been related to forces of masticatory muscles. Whereas muscle forces have been related to the cortical thickness and facial divergence, limited research has been conducted relating cortical bone thickness to facial divergence. Objectives include to asses differences in dentoalveolar buccal cortical bone thickness between hyperdivergent and hypodivergent Bengali population in mandibular posterior region. The aim is to provide reference data for orthodontists placing mini-screw implants for treatment purpose. Materials & Methods:No of subjects 40. Subjects with Frankfort mandibular plane angle more than 29° were classified as hyperdivergent and less than 21° were classified as hypodivergent. Age group is between 14 to 26 yrs.