Factors affecting mandibular residual ridge resorption in edentulous patients: a preliminary report.

The aim of the study was to assess the rate of mandibular residual ridge resorption in edentulous patients and to analyse the factors which determine this process. A group of 35 edentulous patients aged between 51 and 89 years, with a mean age of 74 (65-78) years, were included in the study. Individual factors (age, gender and duration of edentulousness), local biochemical parameters (oral hygiene and history of periodontal diseases) and systemic biochemical parameters (calcium and phosphate metabolism, diet, smoking, alcohol intake and systemic diseases), as well as physical factors involved in the process (the use of prosthetic dentures), were analysed. The study was performed on the basis of the results of dental examinations, assessment of panoramic radiograms, research surveys and total calcium and phosphate serum levels, which were determined using a calorimetric method. Bone resorption in the mandible affected all the study patients to varying extents. More than half the edentulous patients showed a high degree of mandibular residual ridge resorption. The duration of mandibular edentulism was found to be closely associated with values of the radiological IC/IM index, which is generally considered to reflect the degree of mandibular resorption. Total calcium serum levels were shown to correlate positively with the value of IC/IM index in these patients.