Anthropometric study on inter-mental foramina distance of Myanmar populace: A Pilot Study

Abstract

All-on-4 implant procedure is one of the widely used procedures for oral rehabilitation of the edentulous mandible patients in which four implants are placed in the anterior mandible between two mental foramina. The two anterior implants are placed axially and the two posterior implants are placed distally tilted up to 45 degree. Tilting of the distal implants enables the placement of longer implants with increased bone-to-implant contact, improved distribution of load with shorter cantilever arm, improved inter implant distance and improved anchorage in the better-quality anterior bone. Damaging the mental nerves can also be avoided. Thus, determining inter-mental foramina distance (IMFD) is essential for proper implant planning and prosthesis design especially for All-on-4 treatment. The information on this distance of the locals may enable the dentist to safely use the universal surgical guide for All-on-4 procedure or to consider construction of specific guide for Myanmar patients. So, the objective of the study was to evaluate the inter-mental foramina distance (IMFD) of the mandible of the Myanmar populace. Retrospective observational study was conducted. CBCT images of 39 males and 39 females (total 78) were collected from archives of two imaging centers. The distance between the most mesial margins of the mental foramina were measured along the midline of the mandible in axial view. In statistical analysis, unpaired t test was used for different genders and one-way ANOVA was used for different age groups. Mean inter-mental foramina distance were 42.89 mm, 44.19 mm, 44.76 mm, 44.94 mm for ?20 years, 21-40 years, 41- 59 years, ?60 years age groups respectively, and 44.57mm, 43.61 mm for male, female group respectively. There was no statistically significant difference between the above groups (p>0.05). The inter-mental foramina distance in the study populace was such that All-on-4 universal surgical guide can be safely applied for implant surgical procedure.