Changes in volume during the four months’ remodelling period of iliac crest grafts in reconstruction of the alveolar ridge

Our aim was to assess the four months’ resorption rates of onlay iliac crest grafts in atrophic jaws prospectively, and to identify factors that influence them. Twenty-four patients had reconstructions of the alveolar ridge with iliac crest onlay grafts at 30 sites on the mandibles and maxillas. The augmentation volumes were measured on cone-beam computed tomographic (CT) data-sets directly after augmentation (V1), and after four months’ remodelling (V2). Statistical analysis allowed identification of potential influences from the recipient sites, volume of the graft, and the patients’ smoking behaviour. The mean (range) initial onlay graft volume (V1) was 2.82 (0.66 to 6.41) ml. After four months, the mean measured onlay graft volume (V2) was 2.39 (0.47 to 6.21) ml. Mean iliac crest onlay graft volume resorption after four months of remodelling was 0.43 (-0.15 - 1.78) ml (15%). We found no significant differences in the resorption rates of iliac crest onlay grafts between different recipient sites (maxilla and mandible) or in dependence on the volume of iliac crest grafts. Smokers tended to have a higher rate of resorption, but not significantly so (p = 0.056). The results of this study indicate the most favourable resorption rates for iliac crest onlay grafts that we know have seen published to date.