Shape-Retaining Subperiosteal Contour Augmentation

Abstract

A major problem in the reconstruction of atrophic alveolar ridges and maxillofacial bone contour defects with hydroxyapatite (HA) granules is the initial instability of the subperiosteally placed particles. To eliminate the problem of dislocation and migration, we mixed the granules in a syringe with a two-component fibrin sealant in which thrombin solution had been diluted to 1 IU/ml. Between 1987 and 1990 we reconstructed 121 alveolar ridges and 30 maxillofacial contour defects with moldable implants of HA-fibrin sealant. Panoramic radiographics were used to measure the vertical height of the augmented alveolar ridges. The average initial alveolar ridge augmentation was 11.5 mm. Under loading with a denture — which was done after 6 weeks — the vertical height of the augmented ridge decreased by 11% in the first year, 3.7% in the second year, and 2.5% in the third and fourth years. During our 5 years of clinical experience with fibrin as a resorbable biological adhesive for HA granules, this technique has proven suitable for subperiosteal contour augmentation in preprosthetic as well as in orthognathic and reconstructive maxillofacial surgery. A main advantage of the method is the application of the implant as a moldable paste from a syringe. The binder prevents dislocation of granules during delivery, seals periosteum ruptures, and maintains the required bulk and shape during fibrous tissue ingrowth.