Maxillary Sinus Augmentation in the Non‐Human Primate: A Comparative Radiographic and Histologic Study Between Recombinant Human Osteogenic Protein‐1 and Natural Bone Mineral

Abstract

The posterior maxilla has traditionally been one of the most difficult areas to successfully place dental implants due to poor bone quality and close approximation to the maxillary sinus. Sinus augmentation procedures have become a viable means of assuring adequate bone for the placement of dental implants in this area. However, with the techniques currently employed, a considerable variation in the quality of bone attained with the sinus augmentation procedure exists. The purpose of this in vivo study was to evaluate the healing response and bone formation stimulated by 3 doses of recombinant human osteogenic protein-1 (rhOP-1), 0.25, 0.6, and 2.5 mg OP-1 per gram of collagen matrix; natural bone mineral; or collagen matrix alone (control) placed in the maxillary sinus of adult chimpanzees. Results were assessed using clinical, histologic, and radiographic techniques. Radiographic analysis of the computed tomography scans taken at 1 week, and 2.5, 4.5, and 6.5 months revealed a more rapid mineralization with the 2.5 mg OP-1/g collagen matrix and natural bone mineral treatment groups. The incremental bone mineral density (BMD) increase for these 2 treatments from 1 week to 2.5 months was over 2.5 times the increase found with the collagen matrix alone; these 2 treatments also had a higher BMD at the most superior slices evaluated when compared to the other 3 groups. Biopsy specimens were taken at 3.5, 5.5, and 7.5 months and for all 5 treatment groups bone formation was observed at all time points in the majority of the specimens. At 7.5 months the 2.5 and 0.6 mg OP-1/g collagen matrix treatment groups had an increase in the percent bone area when compared to the matrix alone control. In conclusion, these results demonstrate that sinus augmentation with natural bone mineral or 2.5 mg OP-1/g collagen matrix induce comparable radiographic and histologic evidence of bone formation and that both of these treatments performed superior to the control group of collagen matrix alone based upon all methods of evaluation.

Bone morphogenetic proteins in human bone regeneration

“…In dental extraction sites and in sinus augmentation in chimpanzees, rhOP-1 aided bone formation (107,108). In goat maxillary sinus floor elevations, implantation of rhBMP-2 on a collagen carrier showed increased radio-opacity, histological examination revealing the presence of dense trabeculae and bone marrow, but no cortical bone, 12 weeks after surgery (109).…”

Maxillary sinus grafting

“…Margolin et al 85 evaluated the healing response and bone formation stimulated by three doses of recombinant human osteogenic protein-1 (rhOP-1; 0.25, 0.6, and 2.5 mg/g collagen matrix), natural bone mineral, and collagen matrix alone (control) placed in the maxillary sinus of adult chimpanzees. Sinus augmentation with natural bone mineral or 2.5 mg rhOP-1/g collagen matrix induced comparable radiographic and histologic evidence of bone formation.…”

Efficacy of Platelet-Rich-Plasma (PRP) and Highly Purified Bovine Xenograft (Laddec®) Combination in Bone Regeneration after Cyst Enucleation: Radiological and Histological Evaluation

“…However, in spite of these good properties, synthetic materials have limitations due to their poor mechanical properties and slow biodegradation in vivo [20]. In view of the biological limitations associated individually with graft materials, surgeons have attempted to augment the activity and physical properties with composite grafts combining molecular, cellular, and genetic tissue engineering technologies [21][22][23]. The molecular approach using BMPs has received the most attention over the past decade.…”