Avaliação do reparo de defeitos críticos em calvária de ratos preenchidos com a vitrocerâmica Biosilicato® sintetizada pelo processamento sol-gel: análises histológica e imuno-histoquímica / Evaluation of critical calvarial bone defects of rats filled with glass ceramic Biosilicato® synthesized by sol-gel route: histological and immunohistochemical analysis

Os materiais vítreos podem ser processados por diferentes rotas, dentre elas a convencional por fusão e solidificação ou por rota sol-gel, o que melhora sua bioatividade. O objetivo do presente estudo foi o de avaliar o comportamento biológico da vitrocerâmica Biosilicato® sintetizada pelo processamento sol-gel durante o processo de reparo ósseo em modelo animal. Para tanto, foram utilizados 30 ratos Albinus Wistar, machos, com cerca de três meses de idade e pesando em média 450 gramas. Os mesmos foram submetidos a procedimento cirúrgico para confecção de um defeito de 5mm de diâmetro no osso parietal direito e divididos em 2 grupos, de acordo com o biomaterial estudado: Grupo BS ­ defeitos preenchidos com Biosilicato® particulado convencional (180-212 µm), e Grupo BG ­ defeitos preenchidos com Biosilicato® particulado produzido via rota sol-gel (180-212 µm). Após os períodos de 7, 21 e 45 dias, os animais foram submetidos à eutanásia para remoção dos espécimes para serem preparados e submetidos para análise microscópica morfológica e imuno-histoquímica. Aos 7 dias do grupo BS observaram-se partículas do biomaterial circundadas por tecido de granulação, no centro do defeito próximo e tecido ósseo neoformado próximo as suas paredes. Aos 21 dias, presença marcante de CGMs em contato com o biomaterial e aos 45 dias, biomaterial ora substituído por leucócitos MNs e CGMs ora circundado por tecido conjuntivo. Já no grupo BG aos 7 dias observaram-se numerosas partículas arredondadas do biomaterial circundadas por tecido de granulação. Aos 21 dias, presença de CGMs em contato com o material e/ou em processo de fagocitose e aos 45 dias, eventuais partículas do biomaterial, em sua maioria substituído por leucócitos MNs e CGMs e presença de tecido conjuntivo. Para a quantificação de células positivas marcadas para os marcadores F4/80 (A), CD206 (B), TGFß (C) e iNOS (D), considerando-se o número absoluto das células imunomarcadas houve diferença significativa entre os grupos BS (6,5± 3,33) e BG ( 20±7,55) aos 21 dias para o marcador TGFb. Concluiu-se que a rota sol-gel para síntese da vitrocerâmica testada modificou suas propriedades físico-químicas sem, no entanto, incitar um processo imune-inflamatório deletério, sendo necessários estudos futuros para associar estes resultados às propriedades de bioatividade e osteocondução para atestar sua capacidade de substituto ósseo(AU)

The vitreous materials can be processed by different routes, among them the conventional one by fusion and solidification or by route sol-gel, which improves their bioactivity. The objective of the present study was to evaluate the biological behavior of the glass-ceramic Biosilicato® synthesized by sol-gel processing during the bone repair process in animal model. For this, 30 male Albinus Wistar rats were used, about three months old and weighing on average 450 grams. They were submitted to a surgical procedure to make a 5mm diameter defect in the right parietal bone and divided into 2 groups according to the biomaterial studied: BS group - defects filled with conventional particulate biosilicate (180-212 µm), and Group BG - defects filled with particulate Biosilicate® produced via sol-gel route (180-212 µm). After the 7, 21 and 45 day periods, the animals were submitted to euthanasia to remove the specimens to be prepared and submitted for microscopic morphological and immunohistochemical analysis. At 7 days of the BS group biomaterial particles were observed surrounded by granulation tissue, close to the defect wall and noticed if neoformed bone tissue at 21 days, the presence of CGMs in contact with the biomaterial and at 45 days, biomaterial ora replaced by leukocytes MNs and CGMs or surrounded by connective tissue, already in the BG group at 7 days there are numerous rounded biomaterial particles surrounded by granulation tissue at 21 days, presence of CGMs in contact with the material and / or in process of phagocytosis and at 45 days, any particles of the biomaterial, mostly replaced by leukocytes MNs and CGMs and presence of connective tissue. For the quantification of positive cells marked for the markers F4 / 80 (A), CD206 (B), TGFß (C) and iNOS (D), considering the absolute number of the immunolabelled cells there was a significant difference between the BS and BG groups at 21 days for the TGFb marker. It is concluded that the sol-gel route for the synthesis of the glass-ceramic tested modified its physicochemical properties without, however, inciting a deleterious immune-inflammatory process, and future studies are necessary to associate these results with the properties of bioactivity and osteoconduction to attest its capacity of bone substitute(AU)

Surgical Treatment of Anterior Sinus Wall Fracture Due to Sports Accident.

Frontal bone fractures represent a low percentage of craniofacial fractures. However, a systematic approach and a correct diagnosis are essential for successful treatment and maintenance of physiology of the frontal sinus and late complications. The purpose of this study was to report a clinical patient with anterior wall fracture of the frontal due to sports accident sinus that was surgically treated.

Immediate Treatment of Complex Mandible Fracture in a Pediatric Patient.

The facial fractures in pediatric patients are rare, and they can need an immediate treatment to recover the function and aesthetic to the young patients. However, the open reduction internal fixation is controversial in pediatrics; it can be effectiveness to treat complex mandible fractures. Therefore, we present a case of a pediatric patient with a complex mandible fracture caused by an auto accident. The immediate treatment was successful with the use of open reduction internal fixation.