Histomorphometric analysis of the repair process of autogenous bone grafts fixed at rat calvaria with cyanoacrylate.

OBJECTIVE: The purpose of this study was to perform histological and histometric analyses of the repair process of autogenous bone grafts fixed at rat calvaria with ethyl-cyanoacrylate adhesive. MATERIAL AND METHODS: Thirty-two rats were divided into two groups (n=16), Group I - Control and Group II - Adhesive. Osteotomies were made at the right parietal bone for graft obtainment using a 4-mm-diameter trephine drill. Then, the bone segments were fixed with the adhesive in the parietal region of the opposite side to the donor site. After 10 and 30 days, 8 animals of each group were euthanized and the calvarias were laboratorially processed for obtaining hematoxylin and eosin-stained slides for histological and histometric analyses. RESULTS: An intense inflammatory reaction was observed at the 10-day period. At 30 days, this reaction was less intense, despite the presence of adhesive at the recipient-site/graft interface. Graft incorporation to the recipient site was observed only at the control group, which maintained the highest graft size at 10 and 30 days. CONCLUSIONS: Although the fragment was stable, the presence of adhesive in Group II did not allow graft incorporation to the recipient site, determining a localized, discrete and persistent inflammatory reaction.

Histomorphometric analysis of the repair process of autogenous bone grafts fixed at rat calvaria with cyanoacrylate

OBJECTIVE: The purpose of this study was to perform histological and histometric analyses of the repair process of autogenous bone grafts fixed at rat calvaria with ethyl-cyanoacrylate adhesive. MATERIAL AND METHODS: Thirty-two rats were divided into two groups (n=16), Group I - Control and Group II - Adhesive. Osteotomies were made at the right parietal bone for graft obtainment using a 4-mm-diameter trephine drill. Then, the bone segments were fixed with the adhesive in the parietal region of the opposite side to the donor site. After 10 and 30 days, 8 animals of each group were euthanized and the calvarias were laboratorially processed for obtaining hematoxylin and eosin-stained slides for histological and histometric analyses. RESULTS: An intense inflammatory reaction was observed at the 10-day period. At 30 days, this reaction was less intense, despite the presence of adhesive at the recipient-site/graft interface. Graft incorporation to the recipient site was observed only at the control group, which maintained the highest graft size at 10 and 30 days. CONCLUSIONS: Although the fragment was stable, the presence of adhesive in Group II did not allow graft incorporation to the recipient site, determining a localized, discrete and persistent inflammatory reaction.

Pruebas de debilidad ósea en ratas diabéticas tipo 1: estudio densitometríco y biomecánico / Evidence of bone weakness in type 1 diabetes rats: study densitometric and biomechanical / Evidências da fragilidade óssea em ratos diabéticos tipo 1: estudo densitométrico e biomecânico

El objetivo de este estudio fue evaluar los efectos causados por la diabetes tipo 1 (DM1) en el fémur de ratas por la densidad ósea y las pruebas biomecánicas. Se utilizaron 22 animales (Rattus novegicus albinus), fueron aleatoriamente separados en: C (grupo control) y D (grupo de diabéticos). Para inducir la diabetes tipo 1, los animales recibieron estreptozotocina disuelto en tampón citrato 0,01 M, pH 4,5, a una concentración de 35mg/kg, dosis única, por vía intravenosa. Después de 4 semanas de inducción, fueron sacrificados y los fémures congelados (-20° C). Pruebas biomecánicas se realizaron para determinar la fuerza máxima (Fmáx) la rigidez, y la análisis densitometrica, para obtener la densidad mineral ósea (DMO) y contenido mineral óseo (CMO). La prueba t de Student acusa diferencias significativas en la DMO (p = 0,0190), CMO (p = 0,0264) y Fmax (p = 0,0137) entre los grupos. Por lo tanto, se deduce que, de acuerdo con la metodología utilizada en este estudio, el diabetes tipo 1 inducido llevó a una mayor fragilidad en el fémur.

The purpose of this paper was to evaluate the effects caused by type 1 diabetes (DM1) in the femurs of rats by bone density and biomechanical testing. We used 22 animals (Rattus norvegicus albinus), which were separated randomly into: C (control group) and D (diabetic group). To induce type 1 diabetes, the animals received streptozotocin dissolved in citrate buffer 0.01M, pH 4.5, at a concentration of 35mg/kg, single dose, by intravenous injection. After 4 weeks of induction, the animals were sacrificed and the femurs frozen (-20° C). Biomechanical test were performed to determine the maximum force (Fmax) and stiffness, and densitometry analysis, to obtain the bone mineral density (BMD) and bone mineral content (BMC). The Student t test acknowledged significant differences in BMD (p = 0.0190), CMO (p = 0.0264) and Fmax (p = 0.0137) between groups. Thus it follows that, according to the methodology used in this work, the induced type 1 diabetes led to a greater fragility in the femurs.

O objetivo deste trabalho foi avaliar os efeitos provocados pelo diabetes tipo 1 (DM1) nos fêmures de ratos, pela densitometria óssea e ensaio biomecânico. Foram utilizados 22 animais (Rattus norvegicus albinus), separados aleatoriamente em: C (grupo controle) e D (grupo diabético). Para provocar o DM1, os animais receberam estreptozotocina dissolvida em tampão citrato a 0,01M, pH 4,5, em uma concentração de 35mg/Kg, em dose única, pela via endovenosa. Após 4 semanas da indução, os animais foram sacrificados e os fêmures congelados (-20°C). Foram realizados testes biomecânicos, para a determinação da Força Máxima (Fmáx) e Rigidez, e análise densitométrica para a obtenção da Densidade Mineral Óssea (DMO) e Conteúdo Mineral Ósseo (CMO). O teste t de Student acusou diferenças significativas na DMO (p=0,0190), CMO (p=0,0264) e Fmáx (p=0,0137) entre os grupos. Desta maneira conclui-se que, de acordo com a metodologia usada neste trabalho, o diabetes tipo 1 induzido provocou uma maior fragilidade nos fêmures.

Análise do processo de reparo ósseo de cavidades cirúrgicas preenchidas com osso autógeno e recobertas por membrana de matriz óssea homógena e de politetrafluoretileno em ratos / Process of bone repair of surgical cavities filled out with autogenous bone and covered by a membrane of homogenous bone matrix and polytetrafluoroethylene in rats

Proposição: O objetivo deste trabalho foi avaliar, qualitativa e quantitativamente, o comportamento da membrana de matriz óssea homógena desmineralizada e conservada em glicerinae e membrana de Ptfe no processo de reparo ósseo de cavidades cirúrgicas preenchidas com osso autógeno realizadas em tíbias de ratos Material e Métodos: Foram utilizados 60 ratos (Rattus norvegicus albinus, Wistar) machos, com aproximadamente 250 gramas divididos em três grupos: o grupo I (Controle-sem membrana), grupo II (membrana homógena) e grupo III (membrana de ptfe). Após tricotomia, anestesia e antissepsia foi realizada uma incisão longitudinal nas regiões antero-laterais de cada tibia. Após exposição das tíbias, duas cavidades cirúrgicas de 2mm de diâmetro foram preparadas com trefina em baixa-rotação refrigerada, uma no membro posterior esquerdo e outra no membro posterior direito, sendo a primeira preenchida com o osso autógeno particulado coletado durante a realização das duas cavidades e recobertas pelas membranas utilizadas no estudo. Aos 10 e 60 dias pós-operatórios os animais foram eutanaziados e as peças obtidas foram processadas laboratorialmente para a realização de cortes semi-seriados com seis micrômetros de espessura e corados pela hematoxilina e eosina para análise histomorfométrica. Resultados e Conclusão: A membrana homógena mostrou-se biocompatível e cumpriu sua função e em termos de área óssea neoformada as membranas obtiveram desempenho semelhantes.

Purpose: The aim of this study was to evaluate the behavior of membrane of a demineralized homogenous bone matrix and preserved in glycerin and the Ptfe membrane in the process of bony repair of surgical cavities filled out with autogenous bone accomplished in tibias rats. Materials and Methods: Sixty male rats weighing approximately 250 g were selected and assigned to two groups, as follows. Group I (without membrane), Group II (homogenous membrane) and Group III ( Ptfe membrane). After anesthesia, shaving and antisepsis, a longitudinal incision was made in the anterolateral areas of each tibia. After exhibition of the tibias, two surgical cavities of 2mm of diameter were prepared with trefina in refrigerated low-rotation, one in the left posterior member, other in the right subsequent member, being the first filled out with particulate autogenous bone collected during the accomplishment of the two cavities and covered with the membrane. Ten and sixty days postoperatively, the animals were euthanized and the anatomical pieces were submitted to routine laboratorial processing and serially sectioned to obtain 6-μm-thick sections, which were stained by hematoxylin and eosin for histomorphometric analysis. Results and Conclusions: The homogenous membrane proved to be biocompatible and fulfilled its function and in terms of bone area formation membranes had similar performance.

Repair process of surgical defects filled with autogenous bone grafts in tibiae of diabetic rats.

From a biological standpoint, the best material for reconstruction of bone defects is the autogenous bone graft. However, as tissue healing is affected under diabetic conditions, major changes might take place in the revascularization, incorporation, replacement and remodeling phases of the grafted area. The purpose of this study was to assess the bone healing process in surgical wounds prepared in tibiae of diabetic rats and filled with autogenous bone. Forty male rats (Rattus norvegicus albinus, Wistar) were randomly assigned to receive an endovenous injection (penile vein) of either citrate buffer solution (Group 1 - control; n=20) or streptozotocin dissolved in citrate buffer solution (35 mg/kg) to induce diabetes (Group 2 - diabetic; n=20). After determination of glycemia, the animals were anesthetized and the anterolateral regions of the tibiae of both limbs were shaved, antisepsis was performed and longitudinal incisions were made in each limb. The tibiae were exposed and two 2mm-diameter surgical cavities were prepared: one in the right limb, filled with particulate autogenous bone and the other in the left limb, filled with blood clot. The animals were euthanized at 10 and 30 postoperative days. The anatomic pieces were obtained, submitted to laboratory processing and sections were stained by hematoxylin and eosin and Masson's Trichrome for histomorphologic and histometric analyses. In both groups, the wounds filled with autogenous bone graft showed better results than those filled with blood clot. The control group showed higher new bone formation in wounds filled with autogenous bone graft at 30 days than the diabetic group, but without statistical significance. It may be concluded that, in general, the new bone formation occurred with autogenous graft was quantitatively similar between control and diabetic groups and qualitatively better in the control group.

Repair process of surgical defects filled with autogenous bone grafts in tibiae of diabetic rats

From a biological standpoint, the best material for reconstruction of bone defects is the autogenous bone graft. However, as tissue healing is affected under diabetic conditions, major changes might take place in the revascularization, incorporation, replacement and remodeling phases of the grafted area. The purpose of this study was to assess the bone healing process in surgical wounds prepared in tibiae of diabetic rats and filled with autogenous bone. Forty male rats (Rattus norvegicus albinus, Wistar) were randomly assigned to receive an endovenous injection (penile vein) of either citrate buffer solution (Group 1 - control; n=20) or streptozotocin dissolved in citrate buffer solution (35 mg/kg) to induce diabetes (Group 2 - diabetic; n=20). After determination of glycemia, the animals were anesthetized and the anterolateral regions of the tibiae of both limbs were shaved, antisepsis was performed and longitudinal incisions were made in each limb. The tibiae were exposed and two 2mm-diameter surgical cavities were prepared: one in the right limb, filled with particulate autogenous bone and the other in the left limb, filled with blood clot. The animals were euthanized at 10 and 30 postoperative days. The anatomic pieces were obtained, submitted to laboratory processing and sections were stained by hematoxylin and eosin and Masson's Trichrome for histomorphologic and histometric analyses. In both groups, the wounds filled with autogenous bone graft showed better results than those filled with blood clot. The control group showed higher new bone formation in wounds filled with autogenous bone graft at 30 days than the diabetic group, but without statistical significance. It may be concluded that, in general, the new bone formation occurred with autogenous graft was quantitatively similar between control and diabetic groups and qualitatively better in the control group.

Fibroma de tecido mole da boca / Fibroma of soft tissue of mounth

O presente artigo objetivou realizar uma breve revisão de literatura e apresentar um caso clínico de fibroma em paciente melanoderma, do sexo masculino, com 35 anos de idade, portador de uma lesão nodular exofítica indolor, junto à borda anterior esquerda do ramo ascendente da mandíbula, pediculada, com aproximadamente 1,0 cm em seu maior diâmetro, limites nítidos, flácida, móvel, recoberta por mucosa íntegra, lisa e brilhante e com evolução de aproximadamente 10 anos. Após exérese cirúrgica a análise histopatológica mostrou epitélio estratificado pavimentoso atrófico, tecido conjuntivo denso com feixes entrelaçados de fibras colágenas entremeadas por número variável de fibroblastos, fibrócitos, poucos vasos sanguíneos e células inflamatórias, aspecto típico de fibroma. Acompanhamento clínico de um ano mostrou-se dentro dos padrões de normalidade. Os autores ainda enfatizam a etiologia, características clínico-histopatológicas, tratamentos e prognóstico dessas lesões, bem como, diferenciam neoplasia mesenquimal benigna (fibroma verdadeiro) de hiperplasia fibrosa inflamatória (fibroma traumático)

Carcinoma espinocelular de língua e assoalho de boca em paciente jovem / Squamous cell carcinoma of tongue and floor of mouth in a young patient

Os autores apresentam um caso clínico de carcinoma espinocelular em paciente leucoderma do sexo feminino com 22 anos de idade, fumante há 4 anos, com lesão ulcerada crateriforme em borda lateral de língua e assoalho bucal esquerdo. O exame clínico evidenciou atraso do diagnóstico e erros terapêuticos de vários cirurgiões-dentistas. O objetivo dos autores é abordar aspectos clínico-patológicos, possíveis tratamentos e prognóstico dessa lesão, enfatizando a importância de um melhor preparo do CD em relação aos conhecimentos de câncer bucal e à conduta diante de uma lesão que sugere malignidade.

Tratamento cirúrgico do cisto ósseo traumático por finalidade ortodôntica / Surgical treatment of traumatic bone cyst for orthodontic purpose

O cisto ósseo traumático ou cisto ósseo solitário é uma lesão óssea de etiologia pouco definida, que apresenta como características clínicas uma cavidade vazia, desprovida de membrana ou epitélio, assintomática e que, radiograficamente, apresenta radiolucidez ocasionada pela falta de estrutura na região. Caso clínico: paciente M.A.S., 21 anos, gênero feminino procurou a clínica odontológica para exodontia dos terceiros molares por encaminhamento ortodôntico. Após exame radiográfico panorâmico constatou-se a presenção de lesão radiolúcida de 2 mm de diâmetro na região mentoniana do lado esquerdo, abaixo dos ápices dos dentes 31, 32, 41 e 42 sem envolvê-los. Ao exame clínico não foi observada nenhuma alteração de volume na região. Durante a anamnese nehuma história traumática foi constatada recetemente. Porém, a mãe da paciente recordou que aos 2 anos de idade a filha caiu de um berço traumatizando a região do mento. Após análise de uma radiografia panorâmica antiga, realizada aos 9 anos de idade, a lesão também pôde ser observada, estando esta com diâmetro inferior a 10 mm. Como a paciente necessitava ser submetida a tratamento ortodôntico, optou-se pela abordagem cirúrgica da lesão, o que confirmou o diagnóstico do cisto ósseo traumático. A curetagem realizada foi eficiente como terapia curativa da lesão