ABSTRACT
Objective: In this study, we aimed to determine the action of the tinctures of Hamamelis virginiana, Maytenus ilicifolia, and Casearia sylvestris on tissues. For this, we investigated the histological sections of fixed skin tissue of Wistar rats for the changes in collagen and elastic fibers, epithelial cells, conjunctive cells, epidermal attachments, pigments, and granules using the optical microscopy technique. Since in the literature and published articles, the use of in vivo models, such as Wistar rats, is predominant to evaluate the healing action of herbal medicines. Methods: The tinctures of Hamamelis virginiana, Maytenus ilicifolia, and Casearia sylvestris, and ethanol 70% (blank) were used. The tinctures were obtained at 10% (w/v) through percolation using 70% ethanol (v/v) as the extraction liquid. This study was conducted in duplicate for each tincture and different incubation times (4, 24, and 48 h) at 37 °C in an oven. The slides used in this study (Wistar rat skin) were previously processed at the histology laboratory since the waste material was donated to conduct this experiment. The Research Ethics Committee approved the use of animals of the Life Sciences Center of the Pontifical Catholic University of Campinas (PUC-CAMPINAS) under the protocol approval number 367/08. Before initiating the staining process, the slides were removed from the oven, and the tincture deposited on the slides was removed. Weigert staining was performed subsequently. For semi-quantitative analysis, the histological sections were carefully observed, and the number of collagen and elastic fibers was evaluated based on the following scale: (+) normal fiber presence, (−) slight decrease, (− −) moderate decrease, and (− − −) intense decrease. The images were digitally captured to obtain the results using a photomicroscope. Results: The degradation of collagen fibers was best evidenced upon using Hamamelis virginiana tincture, which is concordant with the existing reports in the literature on its healing action via the precipitation of dermal proteins. Maytenus ilicifolia and Casearia sylvestris tinctures exhibited low proteolytic capacity as they only caused degradation of elastic fibers that are more delicate and very different from collagen in their constitution. Therefore, the application of the latter two as healing agents (which acts through precipitating proteins) is limited. Conclusions: This experimental histological model using the optical microscopy technique exhibits the advantage of agility and high efficiency as a simple and powerful approach.
ABSTRACT
Introdução: A obturação do sistema de canais radiculares empregamateriais e cimentos que devem apresentar, entre outras propriedades,biocompatibilidade com os tecidos perirradiculares. Objetivo: Compararin vivo a resposta do tecido ósseo com dois tipos de biomateriais: conesresilon e cones de guta-percha. Material e métodos: Utilizaram-se 40ratos machos, albinos e da variedade Wistar para implantes de conedos biomateriais nas tíbias esquerdas, parcialmente perfuradas; 20deles receberam implantes de cones de guta-percha e nos outros 20foram implantados cones de resilon. As tíbias direitas de todos osanimais foram parcialmente perfuradas e serviram como controle.Ao final de duas, quatro, oito e 16 semanas pós-implante, retiraramseas amostras do tecido ósseo para análise. As lâminas histológicasforam coradas em HE, fotografadas e analisadas morfologicamente por intermédio do programa TPS Dig? 1.38. A resposta tecidual foianalisada levando-se em consideração a variação da espessura doperiósteo na região do calo ósseo formado. Resultados: Os resultadosforam tratados estatisticamente por Anova, seguida do teste de Tukey(p < 0.05), em que não se observou diferença estatística entre os doismateriais testados na espessura do periósteo. Conclusão: Os cones deguta-percha e resilon, quando implantados em tecido ósseo da tíbia deratos, apresentaram boa tolerância quanto à biocompatibilidade.
Introduction: Root canal system obturation uses filling materials andsealers that should present, among other proprieties, a biocompatibilityto the periradicular tissues. Objective: To compare, in vivo, bonetissue response to two types of biomaterials: Resilon points and guttaperchapoints. Material and methods: For this purpose, 40 male albinoWistar rats were used for implantation of the biomaterial points in theirpreviously perforated left tibia. Twenty rats received gutta-percha pointimplants and the other 20 rats received Resilon point implants. Allanimals had their right tibia partially perforated, as a control group. Atthe end of the 2nd, 4th, 8th and 16th week post-implantation, bone tissuesamples were taken for analysis. Histological sections were stained byHE, photographed, and morphologically analyzed using TPS Dig? 1.38software. Tissue response was analyzed, taking into consideration theperiosteum thickness variation in the formed bone callus area. Results:Data were statistically analyzed by ANOVA, followed by Tukey?s test (p <0.05). There was no statistical difference between the materials tested,when the periosteum thickness was analyzed. Conclusion: Both Guttaperchaand Resilon points were biocompatible and well tolerated whenimplanted in bone tissue of rats.