Transforming growth factor-b (TGF-b) is considered the main inducer of both the a-smooth muscle actin (a-SMA) phenotype and collagen synthesis and deposition and plays a significant role in the tissue repair and the development of fibrosis. Since the PRP constitutes an important source of TGF-b and its efficacy on the craniofacial bone repair remains controversy, the aim of this study was to evaluate the effect of PRP in the presence of levels of TGF-b on PRP samples, as well as in the presence of collagen III and a-SMAþ cells, while comparing these results by means of a histomorphometric analysis of the bone matrix and fibrous deposition on the bone repair. Four bone defects of 16 mm 2 were created on the calvarium of 21 rabbits. The surgical defects were treated with either particulate autograft, particulate autograft mixed with PRP and PRP alone. Animals were euthanized at 15, 30, and 45 days postoperative. Histomorphometric and immunohistochemical analyses were performed to assess repair time, as well as the expression of collagen III, and a-SMA. The histomorphometric results demonstrated intensive deposition of fibrous tissue while hinder bone deposition occurred in PRP groups. These results coincided with higher values of the TGF-b on the PRP sample, also larger occurrence of diffuse collagen III deposition and higher presence of a-SMAþ cells spread among the fibrous tissue. Thus, the higher levels of TGF-b associated with the both expression of collagen III and a-SMA on defect treated with PRP suggest that its biomaterial induce an effect that can be considered similarly to a fibroproliferative disorder. ß

PURPOSE: To verify the effect of highly concentrated platelet-rich plasma (hPRP) in the pathways of bone repair using non-critical defects in the calvaria of rabbits. METHODS: The hPRP was produced from collected venous blood of 21 rabbits. Four non-critical defects of 8 mm in diameter were created on the calvaria of each animal. The defects were all treated differently: autogenous particled bone (APB, group 1), autogenous particled bone associated with hPRP (APB + hPRP, group 2), isolated hPRP (group 3), and blood clot (control, group 4). Animals were submitted to euthanasia on the 2nd, 4th and 6th week postoperatively. Histological and histomorphometric analysis were carried through. RESULTS: After two weeks, groups 1 and 2 were in more advanced stage of repair than 3 and 4. At this period, comparing the groups 1 and 2, no significant differences were found between both, which also happened between the groups 3 and 4. However, after four and six weeks, the group 1 showed a more advanced stage of repair among all the other studied groups, while group 2 was in more advanced signs of bone repair than groups 3 and 4. Comparing groups 3 and 4, after four and six weeks, the least advanced stage of bone repair was found to be within group 3. CONCLUSION: The use of a highly concentrated PRP was considered prejudicial to the repair of non-critical defects in the calvaria of rabbits, either in the association of autogenous particled bone, when compared to autogenous particled bone alone, or in its isolated form, when compared to blood clot (control).

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Osteomas are benign tumors composed of mature compact or cancellous bone. They represent an uncommon lesion that occurs mainly in craniofacial complex bones. In jaws, they can appear on the bone surface as a polypoid or sessile mass, characterizing a peripheral osteoma (PO), or can be a lesion in the medullar space, then it is called central osteoma. In view of the scarcely reported cases about POs, this article presents a case of PO of the maxillofacial area that was surgically resected using hemicoronal approach.

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Background Leukocyte‐platelet‐rich plasma (L‐PRP) is considered an important source of growth factors, especially Transforming growth factor β 1 (TGF‐β1), which modulates the proliferation and regulation of mesenchymal cells, and also exerts an influence on the hematopoiesis, osteogenesis, and adipogenesis in bone microenvironment. Thus, the aim of this study was to evaluate the effect of L‐PRP on the calvarial bone repair and compare its results on the presence of TGF‐β1, CD34, CD45, bone morphogenetic protein 2 (BMP2), BMPR1B, and Runx2 proteins detected by immunohistochemistry. Material and Methods Four bone defects were created on the calvaria of 23 rabbits. The defects were treated with autograft, L‐PRP alone, and L‐PRP mixed with autograft. The animals were euthanized at 2, 4, and 6 weeks post‐surgery. Results Unlike autograft and sham groups, the defects treated with L‐PRP demonstrated significant positivity to TGF‐β1, while the BMP2 was scarce. These results coincided with the lower bone matrix deposited and larger medullary area, which were composed of fibrosis, when treated with only L‐PRP, or intense adiposity on defects filled with L‐PRP mixed with autograft. The fibrosis that occurred was associated with a minor percentage of osteoproteins, intense presence of CD34+ CD45− cells, and significant expression of TGF‐β1 in all time periods analyzed. The adiposity occurred from the major presence of osteoprogenitor BMPR1B + Runx2+ cells simultaneously to BMP2− TGF‐β1+ and CD34+ CD45+/− expressions predominantly on the earlier period. Conclusion From this study, it can be concluded that the L‐PRP used alone or mixed to autograft hindered the osteoneogenesis due to suppression of immunoexpression of BMP2, while the immunopositivity of TGF‐β1 was intense. When used alone, the L‐PRP induced a fibrotic condition associated with TGF‐β1 presence and lack of osteoproteins, but when L‐PRP was mixed to autograft, it induced the presence of the osteolineage cells (BMPR1B + Runx2+), but also inhibited the terminal osteoblastic maturation associated with the lack of BMP2 and the presence of TGF‐β1+, a fact that contributed to cellular transdifferentiation into fat cells.

RESUMOObjetivo: Avaliar o efeito cicatrizante da administração tópica do extrato hidroalcoólico de Aroeira em feridas abertas na região dorsocostal de ratos. Métodos: Utilizou-se 60 ratos Wistar, machos, que tiveram retirado fragmentos de pele com dois centímetros de diâmetro, sob anestesia inalatória com éter etílico. Foram divididos em dois grupos de 30 animais: o grupo Aroeira, que recebeu aplicação do extrato hidroalcoólico da planta, e o grupo controle, que recebeu aplicação de solução salina a 0,9%. Cada grupo foi subdividido em 3 com 10 animais cada para serem observados aos sete, 14 ou 21 dias. As áreas das lesões foram analisadas pelo aspecto macroscópico e por planimetria digital. Os espécimes ressecados das feridas foram analisados por microscopia ótica em colorações de hematoxilina-eosina e tricrômio de Masson. Resultados: Os achados macroscópicos demonstraram reepitelização completa mais precoce no grupo controle aos 14 dias. Pela planimetria digital as áreas médias das feridas dos ratos do grupo controle (0,5278 cm 2 ) foram menores que as das feridas dos ratos do grupo Aroeira (0,6897 cm 2 ), com significância estatística aos 14 dias de pós-operatório (p=0,036). O estudo histológico demonstrou diferença estatística (p=0,023) em relação às células mononucleares no 14º dia de avaliação, com maior número no grupo Aroeira, não havendo diferenças significantes em relação aos outros parâmetros em nenhum dos dias estudados. Conclusão: O extrato hidroalcoólico de Aroeira retardou a reepitelização das feridas da pele dos ratos Descritores: Cicatrização de Feridas. Fitoterápico. Anacardiaceae (Schinus terebinthifolius Raddi) ABSTRACT Purpose: To evaluate the healing effect of the topic administration of the hydroalcoholic extract of Aroeira in open wounds in the dorsocostal region of rats. Methods: Sixty Wistar rats, males, were used. In all animals one skin fragment was removed, with two centimeters in diameter. Inhalatory anesthesia with ethyl ether was done, The rats were divided in two groups of 30 animals: Aroeira group, submitted to an topic application of the hydralcoholic extract of the plant, and control group, with the same process but with 0.9% saline solution. Each group was divided in three sub-groups of 10 animals according to the period of observation: 7, 14 and 21 days. The areas of the injuries were analyzed by the macrocospic aspect and digital planimetry, and the resected segments of the wounds were studied by optic microscopy stainned with hematoxilin-eosine and trichromium of Masson. Results: The macrocospic findings showed early complete reepitelization in the control group by the 14th day. According to the digital planimetry the average wound areas of the rats from the control group (0.5278 cm 2 ) had been smaller than those from the wounds of the rats of the Aroeira group (0.6897 cm 2 ), with statistical significance to the 14th day (p=0.036). The hystologic study showed statistical difference (p=0.023) regarding the mononuclear cells in 14th day of evaluation, with larger number in ...

To the limits of this study, there were no significant histologic and histomorphometric differences in the articular disc between groups with and without TMJ dysfunction.