Healing of alveolar socket with xenogenic biomaterial exposed to oral environment and the effect of enriched hydrogel: a clinical, tomographic, histomorphometric and immunohistochemical evaluation

• Grant number: 20/12740-2
• Support Opportunities: Regular Research Grants
• Start date: October 01, 2021
• End date: March 31, 2024
• Field of knowledge: Health Sciences - Dentistry - Periodontology
• Principal Investigator: Mario Taba Junior
• Grantee: Mario Taba Junior
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated researchers: Carolina Caliári Oliveira ; Francisco Jean Pierre Romero Febres ; Joao de Andrade Garcez-Filho ; Juliana Magro Ribeiro ; Priscila Lima dos Santos Almeida ; Roberta Okamoto ; Valessa Florindo Carvalho

Abstract

The integrity of hard and soft tissues, compromised by physiological and structural changes after tooth loss, is a major challenge in modern implant dentistry. The influence of soft tissue healing in post-extraction sites and its contribution to bone modeling has gained attention. Thus, the null hypothesis of this work is that there is no difference in the quality of soft tissue healing, filling the socket gap with bone substitute leaving this material exposed or covering the area with collagen matrix or hydrogel. 28 patients with an indication for flapless extraction of the posterior teeth will be selected to receive immediate implantation, having the alveolus gap filled with xenogenous biomaterial at the level of the healing cap and gingival level. Two groups will be divided randomly, where a variation of the surgical technique will be the exposed bone graft or the graft covered with collagen matrix sealing the region of the socket around the implant. The quantity and quality of the keratinized tissue in the alveolus region will be monitored during the healing process on days 02, 07 and 30 by means of an evidencing solution (methylene blue 0.05%), standardized photography and immunoenzymatic analyzes of VEGF, IL-1² and FGF-1 levels. Cone beam computed tomography images will also be performed to assess the thickness of soft and hard tissue immediately after implant installation and after 4 months of healing. To complement the findings in the patient's study, the healing process will also be studied in rat maxillary incisor alveoli. In this experimental model, 05 groups of alveoli will be filled with clot, xenogen bone exposed to the oral environment, xenogen bone covered with collagen matrix and xenogen bone covered with hydrogel enriched with a product based on amelogenins or hyaluronic acid. After 2 weeks, histological processing and histomorphometric analysis will be performed in sections stained with Hematoxylin and Eosin, Masson's Trichrome and Sirius Red to evidence collagen fibers and mineralized structures, distinguishing the areas, density and the percentage of type I and III collagens. Student's t-test and ANOVA or non-parametric complementary tests will be used to identify differences between groups. Differences with a p-value <0.05 considered statistically significant. (AU)