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OBJECTIVE: Hypertension disrupts the bone integrity and its repair ability. This study explores the efficiency of a therapy based on the application of mesenchymal stem cells (MSCs) to repair bone defects of spontaneously hypertensive rats (SHR). METHODS: First, we evaluated SHR in terms of bone morphometry and differentiation of MSCs into osteoblasts. Then, the effects of the interactions between MSCs from normotensive rats (NTR-MSCs) cocultured with SHR (SHR-MSCs) on the osteoblast differentiation of both cell populations were evaluated. Also, bone formation into calvarial defects of SHR treated with NTR-MSCs was analyzed. RESULTS: Hypertension induced bone loss evidenced by reduced bone morphometric parameters of femurs of SHR compared with NTR as well as decreased osteoblast differentiation of SHR-MSCs compared with NTR-MSCs. NTR-MSCs partially restored the capacity of SHR-MSCs to differentiate into osteoblasts, while SHR-MSCs exhibited a slight negative effect on NTR-MSCs. An enhanced bone repair was observed in defects treated with NTR-MSCs compared with control, stressing this cell therapy efficacy even in bones damaged by hypertension. CONCLUSION: The use of MSCs derived from a heathy environment can be in the near future a smart approach to treat bone loss in the context of regenerative dentistry for oral rehabilitation of hypertensive patients.
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AIMS: Cell therapy utilizing mesenchymal stem cells (MSCs) from healthy donors (HE-MSCs) is a promising strategy for treating osteoporotic bone defects. This study investigated the effects of interaction between HE-MSCs and MSCs from osteoporotic donors (ORX-MSCs) on osteoblast differentiation of MSCs and of HE-MSCs on bone formation in calvarial defects of osteoporotic rats. MATERIALS AND METHODS: Osteoporosis was induced by orchiectomy (ORX) and its effects on the bone were evaluated by femur microtomography (µCT) and osteoblast differentiation of bone marrow MSCs. HE- and ORX-MSCs were cocultured, and osteoblast differentiation was evaluated using genotypic and phenotypic parameters. HE-MSCs were injected into the calvarial defects of osteoporotic rats, and bone formation was evaluated by µCT, histology, and gene expression of osteoblast markers. KEY FINDINGS: ORX-induced osteoporosis was revealed by reduced bone morphometric parameters and osteoblast differentiation in ORX-MSCs. HE-MSCs partially recovered the osteogenic potential of ORX-MSCs, whereas HE-MSCs were mildly affected by ORX-MSCs. Additionally, the bone morphogenetic protein and wingless-related integration site signaling pathway components were similarly modulated in cocultures involving ORX-MSCs. HE-MSCs induced meaningful bone formation, highlighting the effectiveness of cell therapy even in osteoporotic bones. SIGNIFICANCE: These results provide new perspectives on the development of cell-based therapies to regenerate bone defects in patients with disorders that affect bone tissue.
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Células-Tronco Mesenquimais , Osteoporose , Humanos , Ratos , Animais , Osteogênese , Osso e Ossos/metabolismo , Diferenciação Celular/genética , Osteoporose/metabolismo , Osteoblastos/metabolismo , Células CultivadasRESUMO
ABSTRACT The traumatic bone cyst is an uncommon nonneoplastic lesion of the jaws that is considered as a "pseudocyst" because of the lack of an epithelial lining. This lesion is particularly asymptomatic and, therefore, is diagnosed by routine dental radiographic examination as a unilocular radiolucency with scalloped borders, mainly in the posterior mandibular region. The exact etiopathogenesis of the lesion remains uncertain, though it is often associated with trauma. The objective of this paper is to report one case of atypical traumatic bone cyst involving impacted lower third molar, addressing its clinical and radiographic characteristics, differential diagnosis, treatment through surgical exploration and case follow-up.
RESUMO O cisto ósseo traumático é uma lesão não neoplásica incomum dos maxilares, considerada um "pseudocisto" devido à ausência de um revestimento epitelial. Esta lesão é particularmente assintomática e, portanto, é diagnosticada pelo exame radiográfico odontológico de rotina como uma radioluscência unilocular com bordas recortadas, principalmente na região mandibular posterior. A etiopatogenia exata da lesão permanece incerta, embora esteja frequentemente associada a trauma. O objetivo deste trabalho é relatar um caso de cisto ósseo traumático atípico envolvendo terceiro molar inferior impactado abordando suas características clínicas, radiográficas, diagnóstico diferencial, tratamento por meio de exploração cirúrgica e proservação do caso.
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Abstract Objective The present study aimed to investigate the participation of focal adhesion kinases (FAK) in interactions between osteoblastic cells and titanium (Ti) surfaces with three different topographies, namely, untreated (US), microstructured (MS), and nanostructured (NS). Methodology Osteoblasts harvested from the calvarial bones of 3-day-old rats were cultured on US, MS and NS discs in the presence of PF-573228 (FAK inhibitor) to evaluate osteoblastic differentiation. After 24 h, we evaluated osteoblast morphology and vinculin expression, and on day 10, the following parameters: gene expression of osteoblastic markers and integrin signaling components, FAK protein expression and alkaline phosphatase (ALP) activity. A smooth surface, porosities at the microscale level, and nanocavities were observed in US, MS, and NS, respectively. Results FAK inhibition decreased the number of filopodia in cells grown on US and MS compared with that in NS. FAK inhibition decreased the gene expression of Alp, bone sialoprotein, osteocalcin, and ALP activity in cells grown on all evaluated surfaces. FAK inhibition did not affect the gene expression of Fak, integrin alpha 1 ( Itga1 ) and integrin beta 1 ( Itgb1 ) in cells grown on MS, increased the gene expression of Fak in cells grown on NS, and increased the gene expression of Itga1 and Itgb1 in cells grown on US and NS. Moreover, FAK protein expression decreased in cells cultured on US but increased in cells cultured on MS and NS after FAK inhibition; no difference in the expression of vinculin was observed among cells grown on all surfaces. Conclusions Our data demonstrate the relevance of FAK in the interactions between osteoblastic cells and Ti surfaces regardless of surface topography. Nanotopography positively regulated FAK expression and integrin signaling pathway components during osteoblast differentiation. In this context, the development of Ti surfaces with the ability to upregulate FAK activity could positively impact the process of implant osseointegration.
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Animais , Osteoblastos/efeitos dos fármacos , Sulfonas/farmacologia , Titânio/química , Quinolonas/farmacologia , Proteína-Tirosina Quinases de Adesão Focal/antagonistas & inibidores , Osteoblastos/fisiologia , Sulfonas/química , Propriedades de Superfície , Microscopia Eletrônica de Varredura , Transdução de Sinais , Expressão Gênica , Integrinas/análise , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Osseointegração/efeitos dos fármacos , Ratos Wistar , Quinolonas/química , Proliferação de Células/efeitos dos fármacos , Proteína-Tirosina Quinases de Adesão Focal/análise , Proteína-Tirosina Quinases de Adesão Focal/química , Reação em Cadeia da Polimerase em Tempo RealRESUMO
Abstract Cell therapy associated with guided bone regeneration (GBR) can be used to treat bone defects under challenging conditions such as osteoporosis. This study aimed to evaluate the effect of mesenchymal stem cells (MSCs) in combination with a poly(vinylidene-trifluoroethylene)/barium titanate (PVDF-TrFE/BT) membrane on bone repair in osteoporotic rats. Osteoporosis was induced in female rats by bilateral removal of the ovaries (OVX) or sham surgery (SHAM), and the osteoporotic condition was characterized after 5 months by microtomographic and morphometric analyses. Calvarial defects were created in osteoporotic rats that immediately received the PVDF-TrFE/BT membrane. After 2 weeks, bone marrow-derived MSCs from healthy rats, characterized by the expression of surface markers using flow cytometry, or phosphate-buffered saline (PBS) (Control) were injected into the defects and bone formation was evaluated 4 weeks post-injection by microtomographic, morphometric, and histological analyses. A reduction in the amount of bone tissue in the femurs of OVX compared with SHAM rats confirmed the osteoporotic condition of the experimental model. More bone formation was observed when the defects were injected with MSCs compared to that with PBS. The modification that we are proposing in this study for the classical GBR approach where cells are locally injected after a membrane implantation may be a promising therapeutic strategy to increase bone formation under osteoporotic condition.
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Animais , Feminino , Polivinil/farmacologia , Titânio/farmacologia , Compostos de Bário/farmacologia , Regeneração Tecidual Guiada/métodos , Células-Tronco Mesenquimais/fisiologia , Osteogênese/efeitos dos fármacos , Osteoporose/fisiopatologia , Osteoporose/terapia , Polivinil/química , Fatores de Tempo , Titânio/química , Regeneração Óssea/efeitos dos fármacos , Regeneração Óssea/fisiologia , Ovariectomia , Distribuição Aleatória , Densidade Óssea , Reprodutibilidade dos Testes , Resultado do Tratamento , Ratos Wistar , Compostos de Bário/química , Imageamento Tridimensional , Células-Tronco Mesenquimais/química , Citometria de FluxoRESUMO
Anquilose da ATM pode ser definida como impedimento da excursão normal da mandíbula por comprometimento da articulação ou de suas adjacências. Ela pode ocorrer por sequela de várias patologias, porém tem como principais fatores causais o trauma e a infecção. O seu diagnóstico é feito com base nos exames clínicos e de imagens. Não existe consenso na literatura quanto ao melhor tratamento para a correção da anquilose. Numa revisão, as modalidades de tratamento comumente encontradas são a artoplastia simples, a artroplastia interposicional e a excisão e reconstrução da articulação. Nas reconstruções da ATM com enxerto autógeno, a preferência cabe ao enxerto costocondral devido ao seu potencial de crescimento e remodelação em pacientes juvenis e ao baixo índice de morbidade nos pacientes adultos. Este trabalho tem como objetivo fazer uma breve revisão da literatura e relatar um caso de anquilose em uma criança tratada com enxerto autógeno costocondral. O tratamento se mostrou eficaz em relação à máxima abertura de boca pós-operatória, ausência de recidiva e boa função da articulação.
Ankylosis of the TMJ may be defined as the prevention of normal mandibular excursion due to the involvement of the joint or its surrounding structures. It may be a sequela of various diseases, but the main causal factors are trauma and infection. The diagnosis is based on clinical and imaging examinations. There is no consensus in the literature on the best treatment for the correction of ankylosis. In a review, the most commonly mentioned types of treatment are simple arthroplasty, interpositional arthroplasty, and excision and reconstruction of the joint. In the reconstruction of the TMJ with an autogenous graft, the preferred graft is the costochondral one because of its potential for growth and remodeling in juvenile patients and low morbidity in adult patients.The aim of this paper is to briefly review the literature and report a case of ankylosis in a child treated with an autogenous costochondral graft.The treatment proved effective for maximum mouth opening after surgery; there was no recurrence and good functionality of the joint was achieved.
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Introdução: A osteorradionecrose (ORN) por vezes classificada como uma osteomielite do osso irradiado é uma das mais severas complicações da radioterapia de cabeça e pescoço. Dentre os efeitos deletérios destacam-se também, a xerostomia, cáries, mucosite, disfagia, perda ou alteração do paladar, infecções oportunistas, periodontite e trismo, dentre outros. Objetivo: Sendo assim, o objetivo deste trabalho foi enfatizar os principais fatores predisponentes a ORN, suas características clínicas e terapêuticas. Método: o estudo foi realizado segundo procedimento de revisão de literatura. Resultados: É importante notar que ao cirurgião-dentista como membro de uma equipe oncológica, cabe preparar o paciente para a radioterapia através de medidas preventivas, o companhamento do mesmo durante o tratamento e acima de tudo um correto diagnóstico. Conclusão: Essa atenção é fundamental para garantir um incremento na qualidade de vida desses casos.
Introduction: The osteoradionecrosis (ORN), sometimes classified as an irradiated bone osteomyelitis is one of the most severe complications of radiotherapy for head and neck. Among the deleterious effects also stand out, dry mouth, caries, mucositis, dysphagia, loss or change of taste, opportunistic infections, periodontitis and trismus, among others. Objective: Therefore, the aim was emphasize the main factors that predispose to ORN, their clinical and therapeutic characteristics. Method: the study follow the principles of literature review. Results:. It important to note that the dentist as a member of an oncology team, it should prepare the patient for radiotherapy through preventive measures, followed up during treatment and up everything a correct diagnosis. Conlcusion:These aspects are essential to enhance quality of life insuch cases.