Osteometric and radiological study of the mandibular notch

Abstract

The mandibular notch is located on the superior margin, between two prominent processes of the mandibular ramus, the coronoid and condylar processes. The mandibular notch permits the entry of the masseteric artery, vein and nerve to the deep surface the masseteric muscle. Literary reports documented variations in both, the shape and size of the mandibular notch. Therefore, this study aimed to document the morphology and morphometry of the mandibular notch in the South African Black and Indian population groups and to determine their relationship to sex, age and race (if any). The morphometric and morphological parameters of the mandibular notch were measured and assessed in 149 digital panoramic radiographs and 51 dry mandible specimens (n=400) belonging to the South African Black African and Indian population groups. A combination of classification schemes by Mohammad et al. (2012) and Shakya et al. (2013) were adopted to assess the morphology of the mandibular notch. The morphometric parameter was measured using the Dicom x-ray viewer and a digital vernier caliper. Each of the morphometric and morphological parameters were statistically analyzed using SPSS, to determine if a relationship existed between the afore-mentioned parameters and sex, age and race. This study recorded the round shaped mandibular notch to be the most prevalent type in both sexes with a combined incidence of 44.2%. The length of the mandibular notch was reported to be greater in males than females and concurred with previous studies. However, the selected South African group displayed a smaller mandibular notch than the Japanese and Chinese population groups. Furthermore, this study documented population differences among the South African population group, as the Black African population group showed a wider mandibular notch than the Indian population group. This suggests that population-specific differences may exist for both the morphological and morphometric parameters of the mandibular notch. However, only a statistically significant relationship between the length of the mandibular notch with age and race was documented. The mandibular notch may be of clinical significance to maxillofacial surgeons for surgical and reconstructive procedures, in addition it may also aid forensic anthropologists in the identification of unknown remains.