Effect of topical PTH, increased to Biogran® on the peri-implant defect in orchiec...
| Grant number: | 13/24324-0 |
| Support type: | Regular Research Grants |
| Duration: | August 01, 2014 - July 31, 2016 |
| Field of knowledge: | Health Sciences - Dentistry |
| Principal Investigator: | Arthur Belem Novaes Junior |
| Grantee: | Arthur Belem Novaes Junior |
| Home Institution: | Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil |
| Assoc. researchers: | Raquel Rezende Martins de Barros |
Abstract
At the present time, special attention is given to the factors that may interfere in buccal bone plate preservation, considering its high fragility. Among these, there are the immediate implants and the improvement on the surgical techniques for their placement, and the modifications on the interface implant-abutment. Thus the present study will investigate immediate implants placed with the flapless approach, associated or not with a bone graft in the gaps, which have modified collars that combined the surface Laser-Lok® microchannels created by laser ablation technology, which aims not only the attachment of osteoblasts, but also of fibroblasts in order to preserve the bone height by inhibiting epithelial migration, and the platform-switching design that pretends to depart the implant-abutment interface from the bone crest in order to preserve it. As a second objective, the fresh alveoli will be treated or not with a new bone graft (a highly purified bovine xenograft) to verify its ability in preserving the alveolar bone volume.Therefore, the mandibular premolars of 8 dogs will be extracted during flapless surgeries and 4 implants will be installed in each hemi-arch. The gap between the buccal bone plate and the implant of 2 implants in each hemi-arch will be treated with a bone graft (LADDEC®). All implants will have collars surface treated with the Laser-Lok®, in addition to the platform-switching design. To evaluate the effectiveness of this design, the implants will be placed randomly in two different levels in relation to the top of the bone crest . Another variable will be the treatment or not of the abutments with the same modification Laser-Lok® created for the implant collars. Finally, the behavior of these new implants will be tested during the challenging situation of immediate loading, once metallic prostheses will be immediately installed on the implants. Simultaneously, the remaining alveoli will be filled or not with LADDEC®.Twelve weeks after treatment, the dogs will be euthanized and specimens of interest will be separated and properly prepared for the analysis of computed microtomography and histomorphometry by light microscopy. For the latter, the blocks containing the implants will be sectioned bucco-lingually. The research parameters will be: volume and total area, volume and area of new bone formation, bone density, bone-implant contact, vertical and horizontal coronal bone remodeling, and also the level of insertion of the soft tissue around the implants and the remaining bone graft particles. Besides, the parameters for the alveoli evaluation will be: volume and total area, volume and area of new bone formation, bone density and buccal bone thickness remodeling.Finally, the parameters that can be obtained in both techniques will be compared in order to validate the computed microtomography technology as an alternative to conventional histomorphometry. (AU)