Resumo Introdução Devido a seus resultados positivos sobre o tecido ósseo o estrôncio passou a ser utilizado também como coadjuvante de processos de neoformação óssea, principalmente procedimentos cirúrgicos maxilo-faciais. Objetivo Avaliar se a suplementação de estrôncio (Sr) não radioativo melhora a osseointegração de implantes de titânio em ratos. Material e método Setenta ratos machos (Rattus Norvegicus) foram divididos aleatoriamente em 5 grupos, de acordo com a suplementação sistêmica: Controle - solução salina; SRAN50 - ranelato de estrôncio (SRAN) 50mg/kg/dia; SRAN625 - SRAN 625mg/kg/dia; SCAR/SCHL30 - carbonato de estrôncio e cloreto de estrôncio (SCAR/SCHL) 30mg/kg/dia; SCAR/SCHL365 - SCAR/SCHL 365mg/kg/dia. Os medicamentos foram administrados por gavagem, uma vez ao dia, iniciando 15 dias antes da cirurgia (1 implante de titânio em cada tíbia), e persistiram por 15 ou 60 dias. As tíbias direitas foram utilizadas para avaliação biomecânica (torque de remoção) e imuno-histoquímica (Osteocalcina – OCN e proteína morfogenética óssea - BMP-2). As esquerdas foram utilizadas para avaliação microtomográfica e histomorfométrica. Resultado Aumento do torque de remoção para SRAN625 e SCAR/SCHL365 foi observado quando comparado ao Controle, em 15 dias. Entretanto, não foram encontradas diferenças no período de 60 dias entre os grupos. A avaliação microtomográfica mostrou maior volume ósseo em 60 dias, comparado a 15 dias, para todos os grupos, exceto SCAR/SCHL30. Quando todos os grupos foram comparados, não foram observadas diferenças no período de 15 dias, enquanto no período de 60 dias SRAN625 e SCAR/SCHL365 foram estatisticamente maiores que o Controle. Na análise imuno-histoquímica, doses maiores (SRAN625 e SCAR/SCHL365) levaram a um aumento de BMP-2 em 15 dias. A análise histomorfométrica não revelou diferenças entre os grupos quanto ao contato osso-implante e área óssea ao redor das roscas do implante. Conclusão Este estudo sugere que concentrações mais altas de Sr sistêmico levam a parâmetros relacionados à osseointegração melhorados de forma variável quanto à avaliação biomecânica e microtomográfica. maxilofaciais. maxilofaciais maxilo faciais. faciais maxilo-faciais (Sr Rattus Norvegicus sistêmica salina SRAN5 (SRAN 50mg/kg/dia 50mgkgdia mgkgdia 50mg kg dia mg SRAN62 625mg/kg/dia 625mgkgdia 625mg SCARSCHL30 SCARSCHL SCAR SCHL30 SCHL SCAR/SCHL3 (SCAR/SCHL 30mg/kg/dia 30mgkgdia 30mg SCARSCHL365 SCHL365 SCAR/SCHL36 365mgkgdia 365mg 365mg/kg/dia gavagem 1 ( tíbia, tíbia , tíbia) 6 imunohistoquímica imuno histoquímica Osteocalcina BMP2. BMP2 BMP 2 . BMP-2) Entretanto comparados imunohistoquímica, histoquímica, (SRAN62 BMP- ossoimplante osso SRAN6 SCARSCHL3 SCHL3 SCARSCHL36 SCHL36 (SRAN6

Abstract Introduction Due to its positive results on bone tissue, strontium also began to be used as an adjuvant in bone neoformation processes, mainly maxillofacial surgical procedures. Objective To assess if the non-radioactive strontium (Sr) supplementation enhances the osseointegration of titanium implants in rats. Material and method Seventy male rats (Rattus Norvegicus) were randomly divided into 5 groups, according to the systemic supplementation: Control - saline solution; SRAN50 - strontium ranelate (SRAN) 50mg/kg/day; SRAN625 - SRAN 625mg/kg/day; SCAR/SCHL30 - strontium carbonate and strontium chloride (SCAR/SCHL) 30mg/kg/day; SCAR/SCHL365 - SCAR/SCHL 365mg/kg/day. The drugs were administered via gavage, once a day, starting 15 days before surgery (1 titanium implant in each tibia), and persisted for 15 or 60 days. The right tibiae were used for biomechanical (removal torque) and immunohistochemical (Osteocalcin – OCN, and bone morphogenetic protein - BMP-2) evaluation. The left were used for microtomographic, and histomorphometric evaluation. Result Increased removal torque for SRAN625 and SCAR/SCHL365 were observed when compared with the Control, in 15 days. However, no differences were found in the 60-days period among the groups. Microtomographic evaluation showed larger bone volume at 60 days, compared to 15 days, for all groups but SCAR/SCHL30. When all groups were compared, no differences were seen in the 15-days period, while in the 60-days SRAN625 and SCAR/SCHL365 were statistically higher than the Control. In the immunohistochemical analysis, higher doses (SRAN625 and SCAR/SCHL365) led to an increase of BMP-2 in 15 days. Histomorphometric analysis revealed no differences among the groups regarding bone-to-implant-contact and bone area around the implant threads. Conclusion This study suggests that higher concentrations of systemic Sr lead to variably improved osseointegration-related parameters regarding the biomechanical and microtomographic evaluation. tissue processes procedures nonradioactive non radioactive (Sr Rattus Norvegicus solution SRAN5 (SRAN 50mg/kg/day 50mgkgday mgkgday 50mg kg day mg SRAN62 625mg/kg/day 625mgkgday 625mg SCARSCHL30 SCARSCHL SCAR SCHL30 SCHL SCAR/SCHL3 (SCAR/SCHL 30mg/kg/day 30mgkgday 30mg SCARSCHL365 SCHL365 SCAR/SCHL36 365mgkgday 365mg 365mg/kg/day gavage 1 ( tibia, tibia , tibia) 6 Osteocalcin OCN BMP2 BMP 2 However 60days 15days (SRAN62 BMP- bonetoimplantcontact contact threads osseointegrationrelated related SRAN6 SCARSCHL3 SCHL3 SCARSCHL36 SCHL36 (SRAN6

Resumo Introdução Para o sucesso da reabilitação com implantes suportados e da manutenção dos resultados a longo prazo na região anterior da maxila, é imperativo que o paciente possua qualidade e quantidade óssea adequadas. Objetivo O objetivo deste estudo foi avaliar o ganho e a estabilidade óssea após a reconstrução com malha de titânio na região anterior da maxila, independentemente do biomaterial utilizado para o aumento ósseo. Material e método Utilizamos dados de pacientes oriundos do banco de dados da Faculdade, focando em indivíduos que haviam passado por reabilitação na maxila anterior previamente aumentada com enxertos ósseos e fatores de crescimento em conjunto com malha de titânio. Este estudo de coorte retrospectivo envolveu pelo menos 10 pacientes que atenderam aos critérios de inclusão. Resultado De um total de 39 registros no banco de dados de pacientes que passaram por cirurgia de regeneração óssea guiada utilizando malha de titânio, doze atenderam aos critérios de inclusão, enquanto os demais foram excluídos. Assim, foram obtidos 17 sítios adequados para o estudo, envolvendo 12 pacientes e um total de 276 medições tomográficas. Houve um aumento notável na espessura óssea em todos os níveis de avaliação em relação ao ápice da crista óssea, tanto imediatamente (T1) quanto seis meses após a cirurgia (T2), em comparação com as medições iniciais (T0). Além disso, a espessura óssea tende a aumentar com a proximidade do nível apical. Conclusão A utilização da malha de titânio combinada com vários biomateriais resultou em resultados favoráveis em termos de aumento do volume ósseo. adequadas ósseo Faculdade 1 inclusão 3 excluídos Assim 27 tomográficas T1 T (T1 T2, T2 , (T2) T0. T0 . (T0) disso apical 2 (T (T2 (T0

Abstract Introduction For a successful implant-supported rehabilitation and long-term maintenance in the anterior maxilla, it is imperative that the patient possesses adequate bone quality and quantity. Objective The aim of this study was to assess bone gain and stability following reconstruction with titanium mesh in the anterior region of the maxilla, irrespective of the biomaterial used for bone augmentation. Material and method Patient follow-up data were obtained from the Faculty's follow-up database. The focus was on individuals who had undergone rehabilitation in the anterior maxilla, previously augmented with bone grafts and growth factors in conjunction with titanium mesh. This retrospective cohort study involved at least 10 patients who met the inclusion criteria. Following an initial review of medical records, the eligible patients were invited for evaluation appointments. Result Out of 39 patients who had undergone guided bone regeneration surgery using titanium mesh, 12 met the inclusion criteria. As such, 17 sites suitable for the study were obtained, from which total of 276 tomographic measurements were then taken. There was a noticeable increase in thickness at all assessment levels relative to the bone crest apex, both immediately (T1) and six months post-surgery (T2), compared to baseline measurements (T0). Moreover, bone thickness tended to increase with the proximity to the apical level. Conclusion The use of titanium mesh combined with various biomaterials has yielded favorable outcomes in terms of augmenting bone volume. implantsupported implant supported longterm long term maxilla quantity augmentation followup follow up Facultys Faculty s database 1 criteria records appointments 3 such 27 taken apex T1 T (T1 postsurgery post T2, T2 , (T2) T0. T0 . (T0) Moreover level volume 2 (T (T2 (T0

Resumo O objetivo deste estudo foi avaliar a osseointegração de uma superfície hidrofílica (jateamento + ataque ácido + imersão em solução isotônica) em comparação com uma superfície controle (jateamento + ataque ácido) usando um modelo experimental de osso de baixa densidade. Para realizar o estudo, 24 coelhos foram submetidos a instalação de 4 implantes bilateralmente no osso ilíaco: 2 implantes com superfície controle e 2 implantes com superfície hidrofílica. Os coelhos foram eutanasiados com 2, 4 e 8 semanas após a instalação dos implantes. Após a eutanásia, um implante de cada superfície foi usado para avaliar o torque de remoção, e o outro implante foi utilizado para execução de cortes histológicos não descalcificados e avaliação de contato osso implante (% BIC) bem como a fração da área tecido ósseo entre as roscas do implante (% BBT). Os implantes com superfície hidrofílica apresentaram maior %BIC (42.92 ± 2.85% vs. 29.49 ± 10.27%) e % BBT (34.32 ± 8.52% vs. 23.20 ± 6.75%) (p < 0.05) no período de 2 semanas. Além disso, a superfície hidrofílica apresentou maior torque de remoção no período de 8 semana (76.13 ± 16.00 Ncm2 vs. 52.77 ± 13.49 Ncm2) (p<0.05). Implantes com a superfície hidrofílica apresentaram aceleração no processo de osseointregração, culminando em melhor estabilidade secundária no osso de baixa densidade em relação a implantes com superfície controle. jateamento isotônica ilíaco eutanásia ( BIC BBT. . BBT) 42.92 4292 42 92 (42.9 285 85 2.85 vs 2949 29 49 29.4 10.27% 1027 10 27 34.32 3432 34 32 (34.3 852 52 8.52 2320 23 20 23.2 6.75% 675 6 75 p 0.05 005 0 05 disso 76.13 7613 76 13 (76.1 1600 16 00 16.0 Ncm 5277 77 52.7 1349 13.4 p<0.05. p005 p<0.05 (p<0.05) osseointregração 42.9 429 9 (42. 28 2.8 294 29. 10.27 102 1 34.3 343 3 (34. 5 8.5 232 23. 6.75 67 7 0.0 76.1 761 (76. 160 16. 527 52. 134 13. p00 p<0.0 (p<0.05 42. (42 2. 10.2 34. (34 8. 6.7 0. 76. (76 p0 p<0. (p<0.0 (4 10. (3 6. (7 p<0 (p<0. p< (p<0 (p<

Abstract The aim of this study was to evaluate the osseointegration of a hydrophilic surface (blasting + acid etching + immersion in isotonic solution) in comparison with that of a control surface (blasting + acid etching) using an experimental model of low-density bone. To perform the study, 24 rabbits were submitted to the installation of 4 implants in the iliac bone bilaterally: 2 implants with a control surface and 2 implants with a hydrophilic surface. The rabbits were euthanized at 2, 4, and 8 weeks after implant installation. After euthanasia, one implant from each surface was used to perform the removal torque analysis, and the other implant was used for the execution of non-decalcified histological sections and evaluation of the bone implant contact (% BIC) as well as the fraction of bone tissue area between the implant threads (% BBT). The implants with a hydrophilic surface presented higher %BIC (42.92 ± 2.85% vs. 29.49 ± 10.27%) and % BBT (34.32 ± 8.52% vs. 23.20 ± 6.75%) (p < 0.05) in the 2-week period. Furthermore, the hydrophilic surface presented higher removal torque in the 8-week period (76.13 ± 16.00 Ncm2 vs. 52.77 ± 13.49 Ncm2) (p<0.05). Implants with a hydrophilic surface exhibited acceleration in the process of osseointegration, culminating in greater secondary stability in low-density bone than in implants with a control surface. blasting solution lowdensity low density bilaterally euthanasia analysis nondecalcified non decalcified ( BIC BBT. . BBT) 42.92 4292 42 92 (42.9 285 85 2.85 vs 2949 29 49 29.4 10.27% 1027 10 27 34.32 3432 34 32 (34.3 852 52 8.52 2320 23 20 23.2 6.75% 675 6 75 p 0.05 005 0 05 2week week Furthermore 8week 76.13 7613 76 13 (76.1 1600 16 00 16.0 Ncm 5277 77 52.7 1349 13.4 p<0.05. p005 p<0.05 (p<0.05) 42.9 429 9 (42. 28 2.8 294 29. 10.27 102 1 34.3 343 3 (34. 5 8.5 232 23. 6.75 67 7 0.0 76.1 761 (76. 160 16. 527 52. 134 13. p00 p<0.0 (p<0.05 42. (42 2. 10.2 34. (34 8. 6.7 0. 76. (76 p0 p<0. (p<0.0 (4 10. (3 6. (7 p<0 (p<0. p< (p<0 (p<

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.

Resumo Este estudo avaliou a osseointegração em áreas enxertadas com osso bovino desproteinizado (DBB) e cerâmica bifásica à base de hidroxiapatita e beta-fosfato tricálcico (HA / TCP) em tíbias de ratos. Defeitos ósseos não críticos foram feitos nas tíbias de 28 ratos que foram divididos aleatoriamente em 2 grupos: DBB: defeitos preenchidos com DBB e HA / TCP: defeitos preenchidos com HA / TCP. Defeitos ósseos foram confeccionados nas tíbias bilateralmente e preenchidos com biomateriais. Após 60 dias, os implantes foram instalados e os animais sacrificados 15 e 45 dias após a instalação dos implantes. A osseointegração foi avaliada por análises biomecânica, microtomográfica e histométrica. Os implantes instalados nos defeitos preenchidos com DBB apresentaram maiores forças de torque de remoção (2,33 ± 0,51 Ncm vs. 1,50 ± 0,54 Ncm) e volume de tecido mineralizado ao redor dos implantes aos 15 dias (34,96 ± 3,68% vs. 25,61 ± 2,95%) e maior contato osso-implante (20,87 ± 8,28% vs. 11,52 ± 7,42%) e área de osso dentro das roscas do implante (26,83 ± 12,35% vs. 11,98 ± 7,56%) no período de 45 dias em comparação com os implantes em áreas enxertadas com HA / TCP. Implantes instalados em áreas enxertadas com DBB apresentaram melhor padrão de osseointegração do que implantes colocados em áreas enxertadas com HA / TCP.

Abstract This study evaluated osseointegration in areas grafted with deproteinized bovine bone (DBB) and biphasic ceramic based on hydroxyapatite and beta-tricalcium phosphate (HA/TCP) in rat tibias. Noncritical bone defects were made in the tibias of 28 rats that were randomly assigned to 2 groups: DBB: DBB-filled defects and HA/TCP: HA/TCP-filled defects. Bone defects were made in the tibias bilaterally and filled with biomaterials. After 60 days, the implants were inserted, and the animals were euthanized 15 and 45 days after the implants were installed. Osseointegration was evaluated by biomechanical, microtomographic and histometric analysis. Implants installed in the defects filled with DBB presented higher removal torque forces (2.33 ± 0.51 Ncm vs. 1.50 ± 0.54 Ncm) and mineralized tissue volume around implants at 15 days (34.96 ± 3.68 % vs. 25.61 ± 2.95 %) and greater bone-implant contact (20.87 ± 8.28 % vs. 11.52 ± 7.42 %) and bone area within implant threads (26.83 ± 12.35 % vs. 11.98 ± 7.56 %) at 45 days compared to the measurements of implants in areas grafted with HA/TCP. Implants installed in defects in areas grafted with DBB had a better osseointegration pattern than implants placed in defects in areas grafted with HA/TCP.

Abstract Objective To evaluate the effect of different protocols of low-level intensity laser therapy (LLLT) irradiation on the osseointegration of implants placed in grafted areas. Methodology 84 rats were randomly allocated into six groups: DBB: defect filled with deproteinized bovine bone; HA/TCP: defect filled with biphasic ceramic of hydroxyapatite/β-tricalcium phosphate ; DBB-LI: defect filled with DBB and treated with LLLT after implant placement; HA/TCP-LI: defect filled with HA/TCP and treated with LLLT after implant placement; DBB-LIB: defect filled with DBB and treated with LLLT after graft procedure and implant placement; and HA/TCP-LIB: defect filled HA/TCP and treated with LLLT after graft procedure and implant placement. The bone defects were made in the tibia and they were grafted. After 60 days, the implants were placed. The rats were subsequently subjected to euthanasia 15 and 45 days after implant placement. The pattern of osseointegration and bone repair in the grafted area was evaluated by biomechanical, microtomographic, and histometric analyses. Furthermore, the expression of bone biomarker proteins was assessed. Results The LLLT groups presented higher removal torque, mineralized tissue volume, and a greater degree of osseointegration, especially when LLLT was performed only after implant placement, and these findings were associated with higher expression of BMP2 and alkaline phosphatase. Conclusion LLLT performed on implants placed in grafted areas enhances the osseointegration process.

Abstract Objective: This study aimed to evaluate the effect of avocado/soybean unsaponifiables (ASU) on periodontal repair in rats with induced periodontitis and arthritis. Methodology: Forty-five rats were submitted to periodontitis induction by insertion of ligatures into the upper second molars, maintained for 15 days. These animals were randomly allocated to 3 groups according to the presence of induced arthritis (ART) and the application of the ASU: Control (CTR) group-healthy animals, where saline solution was administered; ART-animals with induced arthritis, where saline solution was administered; ART/ASU-animals with induced arthritis, where ASU (0.6 mg/ kg) was administered. The drugs were administered daily by gavage and the animals were euthanized after 7, 15 and 30 days of the ligature removal. Bone resorption, inflammatory infiltrate composition and marker proteins expression of the differentiation and formation of osteoclasts (RANKL and TRAP) were assessed. Results: The ART/ASU group presented higher bone volume than the ART group at 7 and 30 days after the ligature removal. Furthermore, the ART group presented higher quantity of inflammatory cells and expression of TRAP and RANKL than the other groups. Conclusion: ASU administration improves the repair of periodontal tissues in an experimental periodontitis model in rats with induced arthritis.

Resumo O objetivo deste estudo foi avaliar retrospectivamente a taxa de sobrevivência e sucesso de implantes com superfície tratada por ataque ácido após 8-10 anos de função. Um total de 44 pacientes que receberam 183 implantes há 8-10 anos foram avaliados. Foi realizado exame clínico de todos os dentes e implantes presentes na cavidade bucal. Os seguintes parâmetros foram avaliados: índice de placa visível (IPV), índice de sangramento gengival (ISG), profundidade de sondagem (PS), sangramento à sondagem (SS), nível clínico de inserção (NCI). Para a classificação de sucesso dos implantes foram considerados os seguintes critérios: ausência de infecção peri-implantar com supuração, ausência de mobilidade, ausência de dor persistente ou disestesia e ausência de radiolucência contínua ao redor do implante. Após avaliação, 178 (97.3%) implantes foram classificados como sobreviventes, 155 (84.7%) aderiram aos critérios de sucesso, 5 implantes (2.7%) foram perdidos (1 na maxila e 4 na mandíbula) e 3 implantes (2.0%) não estavam em função. 20 (11%) implantes foram diagnosticados com peri-implantite. Dessa forma, a taxa de sobrevivência foi de 97% e a taxa de sucesso de 85%. Pode-se concluir que os implantes com superfície tratada por ataque ácido apresentaram altas taxas de sobrevivência e sucesso após 8-10 em função.

Abstract The aim of this study was to conduct a retrospective evaluation of the survival and success rates of dental implants with acid-etched surfaces after 8-10 years of function. Forty-four patients who received 183 implants 8-10 years ago were evaluated. Clinical examinations were performed around the implants and natural teeth. The following parameters were measured: visible plaque index (VPI), marginal bleeding index (MBI), probing depth (PD), bleeding on probing (BOP) and clinical attachment level (CAL). To considerer an implant as a success case, the following criteria were considered: absence of peri-implant infection and suppuration, absence of implant mobility, absence of persistent pain and dysesthesia and absence of radiolucency around the implant. Overall, 178 implants were categorized as surviving (97.3%), 155 were categorized as successful (84.7%), 5 implants (2.7%) were lost (1 in the maxilla and 4 in the mandible), and 3 implants were not under functional load (2.0 %). 20 implants were diagnosed with peri-implantitis. Thus, the survival rate was 97% and the success rate was 85%. In conclusion, implants with acid-etched surfaces showed high survival and success rates after a period of 8 to 10 years of function.

Abstract The main objective of this study was to cause bisphosphonate-related osteonecrosis of the jaws to develop in a rodent model. Adult male Holtzman rats were assigned to one of two experimental groups to receive alendronate (AL; 1 mg/kg/week; n = 6) or saline solution (CTL; n = 6). After 60 days of drug therapy, all animals were subjected to first lower molar extraction, and 28 days later, animals were euthanized. All rats treated with alendronate developed osteonecrosis, presenting as ulcers and necrotic bone, associated with a significant infection process, especially at the inter-alveolar septum area and crestal regions. The degree of vascularization, the levels of C-telopeptide cross-linked collagen type I and bone-specific alkaline phosphatase, as well as the bone volume were significantly reduced in these animals. Furthermore, on radiographic analysis, animals treated with alendronate presented evident sclerosis of the lamina dura of the lower first molar alveolar socket associated with decreased radiographic density in this area. These findings indicate that the protocol developed in the present study opens new perspectives and could be a good starting model for future property design.

In a previous study, we evaluated the findings related to the use of resorbable collagen membranes in humans along with DFDBA (demineralized freeze-dried bone allograft). The aim of this subsequent study was to histometrically evaluate in dogs, the healing response of gingival recessions treated with collagen membrane + DFDBA (Guided Tissue Regeneration, GTR) compared to a coronally positioned flap (CPF). Two types of treatment were randomly carried out in a split-mouth study. Group 1 was considered as test (GTR: collagen membrane + DFDBA), whereas Group 2 stood for the control (only CPF). The dogs were given chemical bacterial plaque control with 0.2% chlorhexidine digluconate during a 90-day repair period. Afterwards, the animals were killed to obtain biopsies and histometric evaluation of the process of cementum and bone formation, epithelial migration and gingival level. A statistically significant difference was found between groups with a larger extension of neoformed cementum (GTR = 32.72%; CPF = 18.82%; p = 0.0004), new bone (GTR = 23.20%; CPF = 09.90%; p = 0.0401) and with a smaller area of residual gingival recession in the test group (GTR = 50.69%; CPF = 59.73%; p = 0.0055) compared to the control group. The only item assessed that showed no statistical difference was epithelial proliferation on the root surface, with means of 15.14% for the GTR group and 20.34% for the CPF group (p = 0.0890). Within the limits of this study we concluded that the treatment of gingival recession defects with GTR, associating collagen membrane with DFDBA, showed better outcomes in terms of a larger extension of neoformed cementum and bone, as well as in terms of a smaller proportion of residual recessions.

The purpose of the present study was to evaluate, using a biomechanical test, the force needed to remove implants with surface modification by laser (Nd:YAG) in comparison with implants with machined surfaces. Twenty-four rabbits received one implant with each surface treatment in the tibia, machined surface (MS) and laser-modified surface (LMS). After 4, 8 and 12 weeks of healing, the removal torque was measured by a torque gauge. The surfaces studied were analyzed according to their topography, chemical composition and roughness. The average removal torque in each period was 23.28, 24.0 and 33.85 Ncm for MS, and 33.0, 39.87 and 54.57 Ncm for LMS, respectively. The difference between the surfaces in all periods of evaluation was statistically significant (p < 0.05). Surface characterization showed that a deep and regular topography was provided by the laser conditioning, with a great quantity of oxygen ions when compared to the MS. The surface micro-topography analysis showed a statistical difference (p < 0.01) between the roughness of the LMS (Ra = 1.38 ± 0.23 μm) when compared to that of the MS (Ra = 0.33 ± 0.06 μm). Based on these results, it was possible to conclude that the LMS implants' physical-chemical properties increased bone-implant interaction when compared to the MS implants.