Morphometric Analysis of Antegonial Notch and Posterior Ramus Flexure - its Clinical Significance

Abstract

Mandible bone is the largest and the strongest bone present in the human face. It is a lower jaw bone that is present beneath the maxilla. It holds the lower teeth. Mandible bone is formed from the first pharyngeal arch during its intrauterine life. This bone provides maximum attachment of muscle of mastication and facial expression. The body of the mandible has 2 borders. Ramus of the mandible is a prominent projecting back parts of the horse shoe shaped lower jaw bone. The antegonial notch is present in the inferior border of the mandible at the junction between the ramus and body of the mandible. At the level of the molar occlusal surface there is distinct angulation of the ramus of mandible in its posterior border. This type of angulation on the posterior border is known as posterior ramus flexure. The aim of this research is to morphologically analyse the antegonial notch and posterior ramus flexure and its clinical importance. Fifty-one dry adult human mandibles of unknown sex collected from the Department of Anatomy of Saveetha Dental College. For each mandible, detailed measurements of Antegonial notch and Posterior ramus flexure were taken. There is a presence of 3 types of Antegonial notch and 3 types of Posterior ramus flexure that were discovered and measured separately in fifty-one dry adult human mandibles of unknown sex. The shape, size and the position of the antegonial notch and posterior ramus flexure can be used as one of the tools as an indicator for Sexual Dimorphism. Other researchers have found many indicators for sexual dimorphism as a tool to identify the sex, age, race, etc. There is various evidence that represent and identifies the difference between sex, age and gender and many anatomical features supports it.