Subantral bone grafts, a comparative study of the degree of resorption of alloplastic versus autologous grafts

The placement of dental implants in the posterior region of the maxillary may pose some difficulties caused by the quality and particularly, the quantity of the subantral bone reserve, which are overcome by subantral bone augmentation. The current study performs a comparative evaluation of the quality and especially, of the stability of alloplastic and autologous materials used for subantral bone augmentation. This study included 21 patients who underwent subantral bone augmentation with alloplastic and autologous material. The patients were followed-up over a 24-month period after bone augmentation, during which the osseointegration rate of dental implants and the stability of subantral grafts were evaluated. The rate of failure of dental implants placed in autologous material grafts was 1.89% (0.036±9.398), while the rate of failure of those placed in alloplastic material was 7.69% (1.960±19.194). Bone resorption was higher within 12 months of dental implant placement both for the alloplastic material (9.87±3.76%) and the autologous material (18.87±3.25%), while 12-24 months after bone augmentation it diminished. The implants placed in the autologous bone grafts had a lower rate of failure compared to those placed in the alloplastic material grafts; in contrast, alloplastic material had a lower resorption rate compared to autologous material.