Is a 5 mm rat calvarium defect really critical?

Abstract

PURPOSE: To evaluate bone regeneration in critical defects in the rats´calvariumrats´calvarium. METHODS: Eighteen rats Wistar were divided into three groups of six animals each according to the time of evaluation (15, 30 and 60 days). One calvarium defect of 5mm was made in the parietal bone of each animal under general anesthesia. After the time of evaluation, the animals were killed, when the bone was histological studied and classified according to the type of tissue found: fibrosis or bone. RESULTS: The results showed that in the group of 15 days, in five animals there was only fibrosis. In the group of 30 days, the process of regeneration was growing and in four animals was found bone, in three with partial filling and in the other one with complete filling of the defect. In the group of 60 days, out of the three animals with bone, two had a complete filling of the defect. CONCLUSIONS: There was no bone regeneration in critical defects in 15 days. There was regeneration in the most part of the animals in 30 and 60 days. RESUMO OBJETIVO: Avaliar a regeneração óssea de defeitos críticos em calota craniana de ratos. MÉTODOS: Foram utilizados 18 ratos Wistar que foram distribuídos em três grupos de acordo com o tempo de avaliação (15, 30 e 60 dias). Na calota craniana desses animais foi realizado defeito de 5mm, após anestesia geral prévia. Após o tempo de avaliação, os animais foram submetidos à eutanásia e a calota foi enviada para estudo histológico, quando foi classificada de acordo o tecido encontrado: fibroso ou ósseo. RESULTADOS: Diante dos achados deste estudo, pode-se observar que para o grupo de 15 dias na maioria dos animais, n=5, foi encontrado apenas fibrose. Com o passar do tempo de avaliação, no grupo de 30 dias, o processo de reparo foi evoluindo e em quatro animais já foi encontrado osso, sendo em três com preenchimento parcial e em um completo. No grupo de 60 dias, o processo praticamente permaneceu o mesmo, onde em três animais foi encontrado osso, e, desses, em dois o preenchimento foi completo. CONCLUSÕES: Não houve regeneração óssea do defeito crítico para o período de avaliação de 15 dias. Houve regeneração óssea em grande parte dos animais para o período de avaliação de 30 e 60 dias. Descritores: Regeneração Óssea. Crânio. Neurocirurgia. Ratos.

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Porous titanium scaffolds with injectable hyaluronic acid-DBM gel for bone substitution in a rat critical-sized calvarial defect model

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