Onlay grafting with bovine bone mineral block for horizontal reconstruction of severely atrophic alveolar ridges in anterior maxillae: A 6-year prospective study

Purpose

The aim of this prospective study was to evaluate the efficacy and long-term outcomes of onlay grafting with bovine bone mineral block for reconstruction of horizontal alveolar ridge defects in anterior maxillae.

Materials and methods

Fourteen patients requiring rehabilitation of edentulous anterior maxillae were enrolled to receive onlay grafting in two layers. A cortical block harvested from the lateral aspect of the mandibular ramus was split to acquire approximately 1-mm-thick bone laminae. The cortical bone plate and block graft were compressed and fixed to the recipient sites. After 6 months, the width of the augmentation was recorded, and implants were inserted. Provisional and definitive prostheses were delivered 3 and a further 6 months later. Implant success and associated complications were assessed.

Results

The horizontal bone gain was 8.73 ± 0.82, with a resorption rate of 7.03%. Severe bone resorption was noticed 6 months and 2 years after loading. Fistula occurred with the nonintegrated bovine block on the labial sides of the augmented sites 6 years after loading.

Conclusion

Onlay grafting with bovine bone mineral block in the anterior maxilla may yield optimal horizontal gain with low resorption rates, under the condition of at least 6 months' healing time, mixation with autogenous particulate bone, and application of a membrane to cover the graft site.