Evaluation of the osteoinductive potential of implants and miniplates with bioactive glass-based coating via electrolytic plasma oxidation in the optimization of bone repair in diabetic rats

• Grant number: 21/04001-8
• Support type: Scholarships in Brazil - Master
• Effective date (Start): December 01, 2021
• Effective date (End): February 28, 2023
• Field of knowledge: Health Sciences - Dentistry - Oral and Maxillofacial Surgery
• Principal researcher: Leonardo Perez Faverani
• Grantee: Stefany Barbosa
• Home Institution: Faculdade de Odontologia (FOA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

In order to confirm the promising in vitro effects of the newly developed bioactive glass-based coating (PEO-BG), the present study aims to evaluate the osteoinductive capacity of PEO-BG coatings synthesized via electrolytic plasma oxidation on bone formation in diabetic rats. For this purpose, commercially pure titanium (Ticp) implants and miniplates will be coated by PEO-BG (~ 45.0 Si, 24.5 Ca, 24.5 Na, 6.0 P; w/v %) via PEO (500 V, 1000 Hz, 10% duty cycle, 420 s). Initially, surface characterizations will be conducted to confirm the morphology (Scanning Electron Microscopy - SEM), topography (Confocal Laser Scanning Microscopy - CLSM), chemical composition (Energy Dispersive Spectroscopy - EDS; X-ray Excited Photoelectron Spectroscopy - XPS) and physicochemical properties (Profilometry, Wettability and Surface Free Energy) of the samples. Then, the in vivo study will be conducted using Wistar rats (n = 27) and a diabetes mellitus induction protocol by the administration of streptozotocin (40 mg / kg) will be employed. After 7 days of diabetes induction, the animals will be randomized and allocated to the analyses with implants (n = 15) or miniplates (n = 12). Rats will undergo tibial implant installation surgery, receiving one test implant (PEO-BG/Implant) and one control implant (DAC/Implant) in each tibia. Fracture dressing and osteosynthesis surgery will be performed in the remaining animals for randomized fixation of test miniplate (PEO-BG/Plate) and conventional miniplate (CONV/Plate) in each femur. The animals will be euthanized and the specimens will be sent for analysis of decalcified (14 and 28 days) and calcified (28 days) tissues. Decalcified tissues will be evaluated by histological (HE) and immunohistochemical (RUNX2, OPG, RANKL and OC) analysis. The calcified tissues will be analyzed by Computerized Microtomography (m-CT) and CLSM scanning to evaluate bone tissue dynamics, as well as histometric analysis to determine the area of neoformed bone and the osteoinductive/osteoconductive effectiveness of the coating. Quantitative results will be subjected to normality test (Shapiro-Wilk) and a parametric or non-parametric test will be applied for p<0.05.