Influence of Night-Time of Denture Wearing on the Rate of Alveolar Ridge Resorption in Complete Denture Wearers. A One-Year Study.

Sa？etak Alveolar bone loss (RRR) is a continuous process following tooth extraction, more pronounced during the first few month 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 after 7 years. The RRR results in reduction of face height and counterclockwise rotation of the mandible. So far, the etiology of RRR has not been elucidated. It has been speculated that both systemic and local factors contribute. However, one of the local factors is daytime or daytime and night time denture wearing. The aim of this study was to analyze 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 in daytime only and daytime + night-time denture wearers. 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 the one year period (p<0.01), which was 2.5x bigger in the mandible than in the maxilla. Higher rate of RRR was recorded at frontal sites of the maxillary and mandibular residual ridges compared to lateral sites (p<0.01). Night-time denture wearing made no significant influence on the rate of RRR on any of the five examined sites of the maxilla or the mandible (p>0.05)