Radiographic analysis of dental implant extensions using bone grafts on dogs.

BACKGROUND: Despite the wide use of dental implants they can bring inconveniences, as the moment one reaches osseointegration, these can no longer be extended. Therefore, if a problem occurs regarding its positioning, the options open are substitution or burial of the implant. With implant substitution, there exists the risk of local bone loss and/or future loss of the new implant. PURPOSE: This study proposes a new device (implant extender) for extending the dental implant. The feasibility of this technique is verified through installing dental implant extensions onto the humerus bone of dogs with autogenous bone grafts. MATERIALS AND METHODS: Implants of 3.3 mm in diameter by 6 mm in length and implant extensions with a 3.3 mm diameter and 2.2 mm length were installed onto humerus of 4 healthy dogs, using an autogenous bone graft in a block made from ilium. The biomechanical percussion tests were performed on the implant extensions and then the implant-extension sets were removed for radiographic analysis. RESULTS: In the biomechanical percussion, none of the extensions present clinical mobility. As for the x-rays, these were analyzed by 20 professionals, who concluded that there was a 100% success rate with bone formation around the implants, 74.1% for bone neoformation of the implant extensions, and 80.1% referring to the adaptation of the implant extension. DISCUSSION AND CONCLUSION: Bone formation occurred in every installed dental implant. In most cases, there occurred bone neoformation of the extensions and adaptation of the extension/implant set, according to the x-ray analysis performed by the evaluators. An absence of clinical mobility in the extensions was also observed. Although the results were promising, these techniques still need to be researched in humans, as an alternative for reducing elongated prosthetic crowns or poorly installed implants, as well as the modification of the type of implants among other applications.

Histologia e fisiologia do enxerto ósseo autógeno: revisão de literatua / Histology and physiology of of the autogenous bone graft: review of the literature

Inúmeras técnicas de reconstrução óssea são propostas, seja pela necessidade de quantidade e qualidade óssea, ou por melhor estética para a colocação de implantes. O enxerto autógeno de áreas doadoras intra-bucais, entre elas, é comprovadamente uma das técnicas mais realizadas hoje em Implantodontia (Triplett & Schow, 1996, Widmark et. 1996, Dinato & Polido, 2001). Assim, é de suma importância conhecer as estruturas básicas do desenvolvimento biológico e função do tecido ósseo. Concluindo, o objetivo será estudar a literatura científica a respeito da histologia e fisiologia do osso, bem como a incorporação dos enxertos ósseos autógenos.

A lot of techniques of reconstruction bone are propose, device the necessity or because the quality and quantitative bone, or to improve the esthetic in the place of implantations. The autogenous bone of the intra-oral gift area, between then, one of the main techniques today in Implantology (Triplett & Schow23, 1996, Widmark et al. 199624, Dinato & Polido, 20016). So, is very important to know the basic estructures of biology desenvelopment and the function of bone tissue. Concluding, the purpose will be study the cientific literature of histology and bone physiology, as well the incorporation mechanisms of the autogenous grafts.