Influence of body mass index and the time of edentulousness on the residual alveolar ridge resorption in complete denture wearers

Alveolar bone loss (RRR) is a continuous process following tooth extraction, more pronounced during the first few months after the tooth extraction than later. The RRR in the mandible is twice that of the maxilla during a 1-year period and the mandibular: maxillary resorption ratio increases further to 4:1. So far, the etiology of RRR has not been elucidated. It has been speculated that both systemic and local factors contribute. The aim of this study was to analyse the rate of RRR in five different regions of both jaws on lateral cephalograms of 100 complete denture wearers during a one-year period and to compare the rate of RRR between patients being edentulous over a different period of time and between patients with different body mass index. The height of residual ridges was measured on 5 different sites at the delivery of the dentures and a year later using a calibrated grid. The results revealed significant RRR in a one year period. Body mass index had no significant influence on the rate of RRR on any of the five examined sites of the maxilla or the mandible (p > 0.05), while the period of edentulousness had a significantly higher rate of resorption in first 3 sites of measurement (anteriorly) in patients being edentulous less than 1 year than in patients being edentulous for 1-10 years or for over 10 years (ANOVA, p < 0.05).