Short term sodium alendronate administration improves the peri-implant bone quality in osteoporotic animals

Sodium alendronate is a bisphosphonate drug that exerts antiresorptive action and is used to treat osteoporosis. Objective The aim of this study was to evaluate the bone repair process at the bone/implant interface of osteoporotic rats treated with sodium alendronate through the analysis of microtomography, real time polymerase chain reactions and immunohistochemistry (RUNX2 protein, bone sialoprotein (BSP), alkaline phosphatase, osteopontin and osteocalcin). Material and Methods A total of 42 rats were used and divided in to the following experimental groups: CTL: control group (rats submitted to fictitious surgery and fed with a balanced diet), OST: osteoporosis group (rats submitted to a bilateral ovariectomy and fed with a low calcium diet) and ALE: alendronate group (rats submitted to a bilateral ovariectomy, fed with a low calcium diet and treated with sodium alendronate). A surface treated implant was installed in both tibial metaphyses of each rat. Euthanasia of the animals was conducted at 14 (immunhostochemistry) and 42 days (immunohistochemistry, micro CT and PCR). Data were subjected to statistical analysis with a 5% significance level. Results Bone volume (BV) and total pore volume were higher for ALE group (

Avaliação do reparo ósseo na interface osso/implante em ratos pinealectomizados: análise histológica, imunoistoquimica, histométrica, biomecânica e por microct

O presente estudo teve como objetivo investigar a interface osso / implante em ratos pinealectomizados tratados com melatonina. Métodos: 30 ratos, machos, adultos foram divididos em 3 grupos: controle (CO), pinealectomizados (PnX) e pinealectomizado com melatonina (PNXm). Após 30 dias da Pinealectomia, um implante foi instalado em cada tíbia e a eutanásia foi realizada aos 42 dias. As amostras foram submetidas a histomorfométrica (ELCOI e AON), biomecânica (de torque reverso), microtomografia e análise imunoistoquímica. Os dados quantitativos foram submetidos à análise estatística (P <0,05). Para os resultados histométricos, valores ELCOI para PNX foram menores quando comparados com PNXm (P = 0,0393), enquanto AON não mostrou diferença entre os grupos (P = 0,761). Os valores de torque reverso não mostraram diferença entre os grupos PNX e PNXm (P = 0,5000), e as interações CO vs PNXm, e CO vs PNX mostraram diferença significativa (P <0,05). Os parâmetros volumétricas BV/TV (P = 0,933); Tr.N (P = 0,933); Tb.Th (P = 0,933), Tb.Sp (P = 0,200) não apresentaram diferença estatística. A imunomarcação para OPG, RANKL, TRAP e osteocalcina mostrou similaridade entre os grupos, apesar da PNXm parece assemelhar-se às condições fisiológicas (CO). Portanto, a melatonina melhorou a remodelação óssea na região peri-implante em ratos pinealectomizados.This study aimed to investigate the interface bone/implant in pinealectomized rats treated with melatonin. 30 rats, male, adults were divided into 3 groups: control (CO), pinealectomized (PNX) and pinealectomized with melatonin (PNXm). After 30 days of the pinealectomy, one implant was installed on each tibia and euthanasia was performed at 42 days. The samples were submitted to histometric (BIC and NB), biomechanical (reverse torque), microtomography and immunohistochemical analysis. The quantitative data were subjected to statistical analysis (P<0.05). For the histometric results, BIC values to PNX were lower when compared to PNXm (P=0.0393), whereas NB did not showed difference among the groups (P=0.761). Reverse torque did not show difference between the groups PNX and PNXm (P=0,5000), and the interactions CO vs PNXm, and CO vs PNX showed significantly difference (P<0.05). The volumetric parameters BV/TV (P=0.933); Tr.N (P=0.933); Tb.Th (P=0.933), Tb.Sp (P=0.200) did not present statistical difference. The immunolabeling for OPG, RANKL, TRAP and osteocalcin showed similarity among the groups, despite the PNXm it seems to resemble to physiological conditions (CO). Therefore, melatonin improved the bone turnover in peri-implant region in pinealectomized rats.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Short term sodium alendronate administration improves the peri-implant bone quality in osteoporotic animals

Abstract Sodium alendronate is a bisphosphonate drug that exerts antiresorptive action and is used to treat osteoporosis. Objective The aim of this study was to evaluate the bone repair process at the bone/implant interface of osteoporotic rats treated with sodium alendronate through the analysis of microtomography, real time polymerase chain reactions and immunohistochemistry (RUNX2 protein, bone sialoprotein (BSP), alkaline phosphatase, osteopontin and osteocalcin). Material and Methods A total of 42 rats were used and divided in to the following experimental groups: CTL: control group (rats submitted to fictitious surgery and fed with a balanced diet), OST: osteoporosis group (rats submitted to a bilateral ovariectomy and fed with a low calcium diet) and ALE: alendronate group (rats submitted to a bilateral ovariectomy, fed with a low calcium diet and treated with sodium alendronate). A surface treated implant was installed in both tibial metaphyses of each rat. Euthanasia of the animals was conducted at 14 (immunhostochemistry) and 42 days (immunohistochemistry, micro CT and PCR). Data were subjected to statistical analysis with a 5% significance level. Results Bone volume (BV) and total pore volume were higher for ALE group (P<0.05). Molecular data for RUNX2 and BSP proteins were significantly expressed in the ALE group (P<0.05), in comparison with the other groups. ALP expression was higher in the CTL group (P<0.05). The immunostaining for RUNX2 and osteopontin was positive in the osteoblastic lineage cells of neoformed bone for the CTL and ALE groups in both periods (14 and 42 days). Alkaline phosphatase presented a lower staining area in the OST group compared to the CTL in both periods and the ALE at 42 days. Conclusion There was a decrease of osteocalcin precipitation at 42 days for the ALE and OST groups. Therefore, treatment with short-term sodium alendronate improved bone repair around the implants installed in the tibia of osteoporotic rats

Particularities in the technique of calvaria graft

Calvaria grafts provide good bone quantity for the reconstruction of the atrophic maxilla, and have lower morbidity and resorption rates when compared to iliac crest. The aim of this paper is to present the technique for obtaining a graft of the skull. Initially, the depth of the osteotomy is determined by a manually conducted bur, which establishes the limits of the structures of the skull (outer table, diploe and inner table), making the removal of bone blocks easier and safer. Thus, osteotomies of the blocks are made with greater security, avoiding the complications inherent to surgical technique. The case that will be presented it is from a male patient of 65 years who refused to submit to the iliac crest graft, opting for the calvaria, despite being bald, that is a contraindication for this treatment modality. A delicate suture associated with placement of titanium mesh to maintain the conformation of the patient's skull in the region of the bone defect, created after removal of the graft, provided a good cosmetic result at the donor site. The use of titanium mesh for re-anatomization of bone defects created in the grafts is well indicated for bald patients.Los injertos de calvaria proporcionan una buena cantidad de hueso para la reconstrucción del maxilar atrófico, y tienen menores tasas de morbilidad y reabsorción en comparación con la cresta ilíaca. El objetivo de este trabajo es presentar la técnica para la obtención de un injerto del cráneo. Inicialmente, la profundidad de la osteotomía se determina mediante una fresa manualmente, lo que establece los límites de las estructuras del cráneo (tabla externa, diploe y tabla interna), lo que hace la eliminación de bloques óseos más fácil y segura. Por lo tanto, las osteotomías de los bloques se hacen con mayor seguridad, evitando las complicaciones inherentes a la técnica quirúrgica. Se presenta el caso de un paciente hombre de 65 años que se negó a ser sometido a injerto de cresta ilíaca, optando por la bóveda craneal, a pesar de ser calvo, que es una contraindicación para esta modalidad de tratamiento. Una sutura cuidadosa asociada con la colocación de malla de titanio para mantener la conformación del cráneo del paciente en la región del defecto óseo creado después de obtención del injerto, deja un buen resultado cosmético en el sitio donante. El uso de malla de titanio para la re-anatomización de defectos óseos creados en los injertos está bien indicada para pacientes calvos

Simplificação no tratamento da fratura de ângulo mandibular por meio do acesso intrabucal

Mandibular fractures are the injury most commonly found in the facial bones. They have varied etiology, such as automobile, motorcycle and cycling accidents, physical abuse and falls. The choice of treatment of mandibular fractures most often employed is the reduction and fixation of bone fragments. Regarding fractures involving the mandibular angle, access headgear is the most widely used, in view of the action of masticatory muscles causing greater displacement of fractured stumps. Therefore, the proposal to introduce a conservative approach and facilitated for the treatment of fractures of the mandibular angle, as well as to demystify the contraindication to intraoral approach cases unfavorable fracture displacement, this work is to report a clinical casesurgical mandibular angle fracture, treated by intraoral approach. The fracture was fixed with two plates, one following the external oblique line system (1.5 mm) and a lower system (2.0 mm), with the help of percutaneous trocar. This approach is very promising for these cases, in order to ease the technical as well as by reducing the technical complications of extraoral approach.As fraturas mandibulares são as injúrias mais comumente encontradas nos ossos da face. Possui etiologia variada, destacando-se os acidentes automobilísticos, ciclísticos, motociclísticos, as agressões físicas, quedas, dentre outras. A opção de tratamento mais empregada das fraturas mandibulares consiste na redução e fixação dos fragmentos ósseos. No tocante as fraturas envolvendo o ângulo mandibular, o acesso extrabucal é o mais empregado, tendo em vista a ação da musculatura mastigatória que provoca maior deslocamento dos cotos fraturados. A proposta de uma abordagem conservadora e facilitada para o tratamento das fraturas de ângulo mandibular é apresentada. Também, desmistificar a contra-indicação do acesso intrabucal para os casos de fraturas desfavoráveis ao deslocamento. Este trabalho, além disso, vem relatar um caso clínico-cirúrgico de fratura do ângulo mandibular, tratado por meio do acesso intrabucal. Fixou-se a fratura com duas placas, sendo uma acompanhando a linha oblíqua externa (sistema 1,5 mm) e, outra mais inferior (sistema 2,0 mm), com o auxílio do trocater percutâneo. Esta abordagem é bastante promissora para estes casos, tendo em vista a maior facilidade da técnica, bem como pela redução das complicações inerentes à técnica pelo acesso extrabucal

Bone repair access of BoneCeramic™ in 5-mm defects: study on rat calvaria

<div><p>Abstract Objective: The aim of this study was to evaluate the osteoconductive potential of BoneCeramic™ on bone healing in rat calvaria 5-mm defects. Material and Methods: A 5-mm calvaria bone defect was induced in three groups and the defect was not filled with biomaterial [Clot Group (CG)], autogenous bone (AG), or Bone Ceramic Group (BCG). Animals were euthanized after 14 or 28 days and the bone tissue within the central area of the bone defect was evaluated. Results were compared using ANOVA and Tukey test (p<0.05). Immunohistochemistry was performed using primary antibodies against osteocalcin, RUNX-2, TRAP, VEGF proteins, and 3-dimensional images of the defects in μCT were obtained to calculate bone mineral density (BMD). Results: In BCG, the defect was completely filled with biomaterial and new bone formation, which was statistically superior to that in the GC group, at both time-points (p<0.001 for 14 days; p=0.002 for 28 days). TRAP protein showed weak, RUNX-2 showed a greater immunolabeling when compared with other groups, VEGF showed moderate immunostaining, while osteocalcin was present at all time-points analyzed. The μCT images showed filling defect by BCG (BMD= 1337 HU at 28 days). Conclusion: Therefore, the biomaterial tested was found to be favorable to fill bone defects for the reporting period analyzed.</p></div