Immunohistochemical, histomorphometric and microtomographic comparative study between autogenous bone and xenogenic bone in onlay graft surgery in rabbit mandibles

• Grant number: 17/02116-7
• Support type: Scholarships in Brazil - Doctorate
• Effective date (Start): September 01, 2017
• Effective date (End): February 28, 2019
• Field of knowledge: Health Sciences - Dentistry - Oral and Maxillofacial Surgery
• Principal researcher: Samuel Porfirio Xavier
• Grantee: Erick Ricardo Silva
• Home Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

The search for bone substitutes has increased considerably in recent decades. In this context, the xenogeneic bone has been used in grafting procedures in order to overcome the disadvantages of using autogenous bone. The objectives of this study are: 1) to investigate the histological characteristics of xenogenous bone grafts in block jaw rabbits; 2) to associate, by means of immunohistochemical procedures, the biomolecular events following bone grafting (angiogenesis and osteogenesis parameters) and graft remodeling pattern; 3) to compare, through histomorphometric measures, autogenous grafts and xenogeneic regarding to bone formation and graft remodeling process. Thirty-six adult rabbits male New Zealand White breed, weighing 3.5 to 4.0 kg, will be submitted to onlay graft surgery in the mandible bilaterally. The animals will be divided into two groups: group I - grafting with autogenous bone blocks (n = 6); group II (n = 6) - xenogeneic grafting with bone blocks. Six evaluation periods will be used, with sacrifice scheduled for: 3, 5, 7, 10, 20 and 60 days after surgery. The following primary antibodies will be used: anti-Osteocalcin (OC); anti-collagen type I; anti-osteopontin; and anti-VEGF "Vascular Endothelial Growth Factor," anti-TRAP "Tartare Resistant Acid Phosphatase" anti-Caspase 2, anti-ALP "Alcaline Phosphatase". For histologic and morphometric evaluation, the following structures will be considered: new bone, residual autogenous bone, remaining xenogeneic bone, connective tissue and other relevant findings during analysis. (AU)