Action of a deproteinized xenogenic biomaterial in the process of bone repair in rats submitted to inhalation of cigarette smoke.

PURPOSE: To investigate if the inorganic bovine bone matrix changes the bone formation in rats submitted to inhalation of cigarette smoke. METHODS: Twenty Wistar rats were divided into two groups: Cigarette Clot Group (CCG), which in the inhalation chamber received the smoke of 10 cigarettes, 3 times a day, 10 minutes, for 30 days and had the surgical cavity filled by clot; Cigarette Biomaterial Group (CBG), submitted to the same inhalation technique but with the cavity filled by biomaterial. RESULTS: In CCG there was a significant difference of new bone tissue in the analyzed periods (15 and 45 days), and in 15 days, there was 4.8 ± 0.42 of bone formed and 11.73 ± 0.59 (p <0.05) in 45 days. The CBG also showed a significant difference between the periods of 15 to 45 days, being respectively 6.16 ± 0.30 and 11.60 ± 0.61. However, when the groups were compared, within the same analyzed periods, a significant difference was observed only in the period of 15 days, with the new bone percentage being greater in the CBG. CONCLUSION: The bone matrix acted as an osteoinductive biomaterial, biocompatible and aided in the repair process, mainly in the initial period of recovery.

Action of a deproteinized xenogenic biomaterial in the process of bone repair in rats submitted to inhalation of cigarette smoke

Abstract Purpose: To investigate if the inorganic bovine bone matrix changes the bone formation in rats submitted to inhalation of cigarette smoke. Methods: Twenty Wistar rats were divided into two groups: Cigarette Clot Group (CCG), which in the inhalation chamber received the smoke of 10 cigarettes, 3 times a day, 10 minutes, for 30 days and had the surgical cavity filled by clot; Cigarette Biomaterial Group (CBG), submitted to the same inhalation technique but with the cavity filled by biomaterial. Results: In CCG there was a significant difference of new bone tissue in the analyzed periods (15 and 45 days), and in 15 days, there was 4.8 ± 0.42 of bone formed and 11.73 ± 0.59 (p <0.05) in 45 days. The CBG also showed a significant difference between the periods of 15 to 45 days, being respectively 6.16 ± 0.30 and 11.60 ± 0.61. However, when the groups were compared, within the same analyzed periods, a significant difference was observed only in the period of 15 days, with the new bone percentage being greater in the CBG. Conclusion: The bone matrix acted as an osteoinductive biomaterial, biocompatible and aided in the repair process, mainly in the initial period of recovery.

Efeitos de 03 dietas alcoólicas na reparação óssea em tíbia de ratos / Effects of three alcoholic diets on the bone repair in the tibia of rats

Os efeitos do uso abusivo e prolongado do álcool sobre vários tecidos, incluindo o ósseo, têm sido amplamente estudados. A quantidade de defeitos ósseos criados cirurgicamente e pelos vários tipos de acidentes tem aumentado e existe uma preocupação muito grande quanto ao reparo desses defeitos, associados ao alcoolismo. O objetivo desta pesquisa foi de observar histologicamente os efeitos de 03 dietas alcoólicas na reparação óssea e se o aumento da concentração do álcool também interfere neste fenômeno. Foram utilizados 64 ratos machos (Rattus norvegicus), divididos em 4 grupos de 16 animais cada, assim distribuídos: Grupo controle (C) – animais que não receberam álcool; Grupos Experimentais I, II e III (EI, EII e EIII, respectivamente) - animais que foram submetidos à alcoolização de 6%, 15% e 25% respectivamente, por um período de 90 dias. Após este período a tíbia esquerda de todos os animais foi submetida a uma cirurgia onde se realizou uma cavidade no sentido longitudinal. Quatro animais de cada grupo foram sacrificados em períodos de 10, 20, 40 e 60 dias contados a partir do dia da cirurgia experimental. As tíbias foram retiradas, processadas histologicamente e submetidas às colorações de HE e tricrômico de Masson. Os resultados mostraram que a neoformação óssea foi decrescente de acordo com o aumento da concentração alcoólica e pode-se concluir que as 03 dietas alcoólicas (6%, 15% e 25%) influenciam a neoformação óssea em todas as suas fases, retardando o processo de reparação óssea.

The effects of long-term alcohol abuse on several tissues, including bone, have been extensively studied. Considering the increase in occurrence of bone defects caused by trauma or even created for surgical purposes, the putative influence of alcoholism on bone healing has been a matter of growing concern. The aim of the present study was to assess histologically the effects of three schemes of alcohol intake at different concentrations on bone repair. 64 male rats (Rattus norvegicus) were assigned to four experimental groups (n=16), which received alcohol diluted with drinking water to the final concentrations of 6% (Group EI), 15% (Group EII) or 25% (Group EIII). The control group (Group C) received drinking water. After 90 days, the animals were subjected to a surgical procedure in which a cavity (3 mm in width) was created on the left tibia. Four animals of each group were sacrificed on 10th, 20th, 40th or 60th days after the surgical procedure. The samples were processed for histological analysis, paraffin embedded and stained with hematoxylin and eosin; and Masson tricromic. The qualitative histological analysis showed that the amount of bone neoformation was inversely proportional to the alcohol concentration. It may be concluded that the schemes of alcohol consumption at the concentrations used in the present study (6%, 15% e 25%) led to a decrease in osseous neoformation in all analyzed periods, resulting in delay on the healing process.

Biocompatibility of anionic collagen matrices and its influence on the orientation of cellular growth / Biocompatibilidade de matrizes de colágeno aniônico e sua influência na orientação do crescimento celular

This study aimed to analyze the biocompatibility of anionic collagen matrices, the local bone response following implantation in surgically-created bone defects, and also the influence of the collagen fiber orientation on the neoformed osseous tissue. Seventy two rats (Rattus norvegicus albinus) were used in this experiment. The animals were divided into four experimental groups: Group 1 (control), without implants; Group 2, pericardium medullar implants 12 hours; Group 3, medullar implants of tendon 24 hours, with the long axis of collagen fibers oriented parallel to the long axis of the tibia; and Group 4, medullar implants of tendon 24 hours, with the long axis of collagen fibers perpendicular to the long axis of the tibia. After the experimental surgery, the evolution of the repair process was microscopically evaluated at 7, 15, and 30 days post-surgery. The results demonstrated that the implanted matrices are biocompatible and act as a scaffold inducing bone formation, mainly in the Group 4 animals. At first, cellularity follows the arrangement of collagen fibers, later obtaining a multidirectional growth.

Este estudo apresentou como objetivo, examinar a biocompatibilidade de matrizes de colágeno aniônico, sua respostaóssea local após implantação em defeitos ósseos criados cirurgicamente e a influência da orientação das fibras colágenasno tecido ósseo neoformado. Foram utilizados 72 ratos (Rattus norvegicus albinus) divididos em 4 grupos experimentaisde 6 animais cada: Grupo 1 (Controle), sem implante; Grupo 2, implante medular de pericárdio 12 horas; Grupo 3,implante medular de tendão 24 horas, com o maior eixo de suas fibras colágenas direcionados paralelamente ao maioreixo da tíbia e, Grupo 4, implante medular de tendão 24 horas, com o maior eixo de suas fibras colágenas direcionados perpendicularmente ao maior eixo da tíbia. A evolução do processo de reparo, após a cirurgia experimental, foi avaliada microscopicamente com 7, 15 e 30 dias pós-operatórios. Os resultados demonstraram que as matrizes implantadas são biocompatíveis e funcionam como uma matriz tridimensional induzindo a formação de osso, maior no grupo 4. A celularidade, inicialmente, acompanha o arranjo das fibras colágenas, adquirindo um arranjo multidirecional crescente.