Alveolar wound healing after implantation with a pool of commercially available bovine bone morphogenetic proteins (BMPs): a histometric study in rats

Abstract

The capacity of a commercially available pool of bovine bone morphogenetic proteins (BMPs) to stimulate osteogenesis in the rat alveolar healing was investigated by histometric analysis. Male rats were anesthetized and had their upper incisor extracted. A pool of purified bovine BMPs adsorbed to microgranular resorbable hydroxyapatite was agglutinated with bovine collagen and saline before implantation into the alveolar socket. The implanted and control rats (n=30 per group) were sacrificed 1 to 9 weeks postoperatively, the hemi-maxillae were decalcified, processed for paraffin embedding and semi-serial longitudinal sections were obtained and stained with hematoxylin and eosin. The volume fraction of alveolar healing components was estimated by a differential point-counting method in histologic images. The results showed that in both, control and implanted rats, the alveolar healing followed the histologic pattern usually described in the literature. Quantitative data confirmed that the BMPs mixture did not stimulate new bone formation in the alveolar socket of implanted rats. These results suggest that the pool of BMPs adsorbed to hydroxyapatite and agglutinated with bovine collagen did not warrant incorporation of the osteoinductive proteins to a slow-absorption system that would allow a BMPs release rate compatible to that of new bone formation, and thus more adequate to osteoinduction.

Expression of bone morphogenetic protein-2 after using chitosan gel with different molecular weight on wound healing process of dental extraction

“…Osteocalcin and osteopontin expression marks the late stage of osteoblast differentiation, and BMP-2 is an important factor for osteoblast maturation and osteoblast activity. 2,3,15 In our study, the expressions of BMP-2 in 21 days observation after using chitosan gel with high molecular weight was decreasing. Probably, the activity of ALP has decreased.…”

“…The major proportion of bone formation and the maximum mineral density has occurred in the end of the 2 nd week. In the end of the 2 nd week the activity of ALP has decreased 2 The using of chitosan gel with high molecular weight could increasing the expression of BMP-2. BMP-2 is major growth factor in bone healing.…”

“…The BMP s , released during osteoclastic bone resorption, are capable of inducing differentiation of mesenchymal cells into osteoblasts (osteinduction), stimulating bone formation in both remodeling and repairing process. 1,2 Chitosan is carbohydrate copolymer composed of glucosamine and N-acetyl-D-glucosamine units. Chitosan has a number of properties including biocompatibility, biodegradability, mucoadhesiveness and wound healing capabilities that make it useful as a biomaterial.…”

“…3 Chitosan is very versatile and can be prepared as films, gels, sponges and other forms and has been used in various applications including wound healing and bone tissue engineering. 2,3 Biological activity of chitosan depend on their molecular weight and deacetylation degree. The deacetylation degree and molecular weight are important parameter, which could influences the performance of chitosan in many its application.…”

“…At the end of 2 nd week, there was progressive bone formation, and the end of 3 rd week, most socket filled with thicker bone trabecula surrounding interconnecting space. 2 The increasing expression of BMP-2 on wound healing process of dental extraction could be achieved by using chitosan gel. The aim of this study was to analyzed expressions of BMP-2 for 7, 14 and 21 days after using chitosan gel with different molecular weight on wound healing process of dental extraction.…”