ABSTRACT
ABSTRACT The aim of this study was to evaluate the osseointegration of implants placed in rat tibia sites grafted with Deproteinized Bovine Bone (DBB) and Native Bone (NB). Twenty-eight rats were divided into two groups according to the type of substrate in which the implants were to be placed: NB - implants placed in native bone; DBB - implants placed in areas grafted with DBB. In the DBB group, the bone defect was made and filled with the bone substitute 60 days before placing the implant. The animals were euthanized 15 or 45 days after implant placement. Osseointegration was assessed by the removal torque, volume of mineralized tissues around the implants (BV/TV), bone-implant contact (%BIC), and bone between threads (%BBT). The implants placed in NB presented higher removal torque (8.00 ± 1.26 Ncm vs. 2.33 ± 0.41 Ncm at 15 days and 22.00 ± 2.44 Ncm vs. 4.00 ± 1.41 Ncm at 45 days), higher %BV/TV (47.92 ± 1.54% vs. 33.33 ± 4.77% at 15 days and 70.06 ± 0.91% vs. 39.89 ± 5.90% at 45 days), higher %BIC (39.68 ± 5.02% vs. 9.12 ± 5.56% at 15 days and 83.23 ± 4.42% vs. 18.81 ± 7.21% at 45 days), and higher %BBT (34.33 ± 5.42% vs. 13.24 ± 8.72% at 15 days and 82.33 ± 3.13% vs. 22.26 ± 8.27% at 45 days) than the implants placed in DBB grafted areas. The degree of osseointegration was lower in implants placed in the area grafted with DBB than in NB in rat tibias.
RESUMO O objetivo deste estudo foi avaliar a osseointegração de implantes instalados em sítios enxertados com Osso Bovino Desproteinizado (DBB) e Osso Nativo (NB). Vinte e oito ratos foram alocados em dois grupos de acordo com o tipo de substrato onde os implantes foram colocados: NB - Implantes colocados em osso nativo; DBB - Implantes instalados em áreas enxertadas com DBB. No grupo DBB, o defeito ósseo foi confeccionado e preenchido com o substituto ósseo 60 dias antes da instalação do implante. Os animais foram sacrificados após 15 e 45 dias da colocação do implante. A osseointegração foi avaliada pelo torque de remoção, volume de tecidos mineralizados ao redor dos implantes (%BV/TV), contato direto do osso com o implante (%BIC), e área de osso entre roscas dos implantes (%BBT). Os implantes instalados em NB tiveram um maior torque de remoção (8.00 ± 1.26 Ncm vs. 2.33 ± 0.41 Ncm aos 15 dias e 22.00 ± 2.44 Ncm vs. 4.00 ± 1.41 Ncm aos 45 dias), um maior %BV/TV (47.92 ± 1.54% vs. 33.33 ± 4.77% aos 15 dias e 70.06 ± 0.91% vs. 39.89 ± 5.90% aos 45 dias), um maior %BIC (39.68 ± 5.02% vs. 9.12 ± 5.56% aos 15 dias e 83.23 ± 4.42% vs. 18.81 ± 7.21% aos 45 dias), e um maior %BBT (34.33 ± 5.42% vs. 13.24 ± 8.72% aos 15 dias e 82.33 ± 3.13% vs. 22.26 ± 8.27% aos 45 dias) que os implantes colocados nas áreas enxertadas com DBB. Implantes instalados em áreas enxertadas com DBB apresentaram menor osseointegração que os implantes instalados no osso nativo em tíbias de ratos.
ABSTRACT
ABSTRACT The aim of this pilot study was to evaluate the impact of the association of free gingival graft (FGG) or collagen-matrix xenograft (CMX) to deproteinized bovine bone graft (DBBG) on the preservation of post-extraction sockets with facial-wall defects. Sixteen patients who presented a maxillary tooth with a facial bone defect and indication of extraction were selected. After the surgical procedure, all the post-extraction sockets were filled with DBBG and covered with a collagen membrane. The cervical part of the socket was then sealed with either FGG or CMX. Clinical and tomographic analyses were performed at baseline and 4 months after the grafting procedure. The FGG sockets showed higher values for the width of the bone ridge than the CMX sockets at 4 months. There was no difference regarding biopsy composition. In conclusion, regardless of the type of soft tissue graft used, socket preservation with DBBG at sites presenting facial bone defects enabled implant placement without further guided bone regeneration, whether the sockets were sealed with FGG or CMX.
RESUMO