Differences in static cortical bone remodeling parameters in human mandible and iliac crest

Knowledge of the baseline turnover characteristics, and of possible general and local factors influencing alveolar bone responses, is particularly imp ortant in the planning of oral rehabilitation. The conventional tool used t o obtain information on bone turnover is the iliac crest biopsy, but it is not clear whether it mirrors the situation involving the jaws. The aim of t his study was to compare static bone remodeling parameters in the mandible and in the iliac crest to obtain baseline values for the mandible and to te st the hypothesis of site specificity of bone remodeling. Bone specimens we re obtained from 50 subjects (mean age 64 +/- 17) at autopsy. Three sites w ere sampled: iliac crest; jaw angle; and foramen mentalis area. In addition , occlusal status was recorded. On undecalcified thin sections, cortical po rosity (Ct.Po), eroded sites (ESi), formative sites (FSi), osteonal diamete r (On.Dm), Haversian canal diameter (H.Ca.Dm), and wall width (W.Wi) were m easured. Ct.Po in the jaw angle and in the foramen mentalis area was lower (48% and 50%, respectively) than in the iliac crest, as was ESi and FSi (80 % in the jaw angle and 74% in the foramen mentalis area). In the foramen me ntalis area, Ct.Po was greater in subjects with occlusion. On.Dm, H.Ca.Dm, and W.Wi were significantly larger and mutually correlated within the mandi ble, whereas no correlation was found between mandibular sites and iliac cr est. Static cortical bone remodeling parameters are different in the mandib le and the iliac crest, thus confirming the hypothesis of site specificity of bone remodeling. Within the mandible, the parameters were correlated, wh ereas there was no correlation between the mandible and the iliac crest. Th is could be ascribed to the different functional demands to the mandible an d the iliac crest, which was also reflected in the observed influence of fu nctional occlusion on bone remodeling in the mandible. It can thus be concl uded that bone reaction to dental intervention is more dependent on the loc al environment than on general bone turnover as reflected by the iliac cres t. (C) 1999 by Elsevier Science Inc. All rights reserved.