Early Implant Placement in Bilateral Sinus Floor Augmentation Using Iliac Bone Block Grafts in Severe Maxillary Atrophy: A Clinical, Histological, and Radiographic Case Report
Effectively restoring a grossly atrophic maxilla can be difficult for the implant surgeon. The placement of dental implants in patients who are edentulous in the posterior maxilla can present difficulties because of deficient posterior alveolar ridge and increased pneumatization of the maxillary sinus, resulting in a minimal hard tissue bed. Implant placement requires adequate quality and quantity of bone, especially in the posterior maxilla. Insufficient bone height and width in this area of the maxilla, because of expansion of the maxillary sinus and atrophic reduction of the alveolar ridge, represents a contraindication for conventional insertion of dental implants. The reconstruction of edentulous patients with adequate bone volume and density by the use of bone graft and, subsequently, the placement of dental implants has become a viable treatment option with high predictability. It is commonly shared that autologous bone graft is the gold standard grafting method in the augmentation of Higmoro antrum and in any kinds of guided bone regeneration. In this article, the authors report a case of severe maxillary atrophy that is augmented by block bone graft harvested from iliac crest. An early placement of implants is possible due to the quick healing of the site, as proven by histologic examinations.Abstract

Three-dimensional computerized tomography scan showing how the patient appears at the clinical inspection.

Frontal view computerized tomography scan showing the thin residual alveolar crest.



Biopsy at 20 days after surgery: the histological aspect of the iliac bone graft reveals osteocyte lacunae full of vital osteocytes, which represent a sign of the grafted bone's rapid revascularization. (A) Lamellar-type cortical bone of the ilium that faces to maxillary antrum. (B) Cancellous part of the block graft with bone trabeculae and medullary spaces. (C) Bone grafted/maxillary alveolar ridge interface (original magnification ×100). At a higher magnification (×200), a newly formed trabeculae bone bond with ordinal trabeculae of the original maxillary bone due to osteoconduction is clearly noted.

Bone biopsy at 3 months after the bone augmentation procedure: histological aspect of the original bone residual alveolar crest (A), which, after healing, appears completely fused to the iliac bone block graft (B). (Original magnification ×25, hematoxylin and eosin).