RESUMO
Limitations of current regeneration modalities underscore the importance of restoring the three-dimensional (3D) microenvironment of periodontal development, which is able to elicit the intrinsic capacity of mesenchymal stem cells to proceed to engage in a redevelopment-like program. With increased attention for the potential therapeutic applications of periodontal ligament stem cells (PDLSCs) in periodontal regeneration, it has been proposed that bone marrow mesenchymal stem cells (BMMSCs) are very likely another cell source of physiological repair of periodontal tissues. With this in mind, enlightened from the research targeting the fabrication of laminar structures such as liver and kidney with heterotypic stratification of cell sheets, we proposed a novel possible strategy based on self-assembly approach, which is akin to the physiological phenomenon that occurs during organogenesis, to enhance complete reconstruction of functional complex periodontium-organ systems. We assumed that in this strategy, using the intrinsic capacity of monodispersed cells to self-assemble into a microtissue such as a 3D spheroid, bilayered cell pellet constructs comprising calcified bone-forming cell pellets (i.e., BMMSCs) and cementum/PDL-forming cell pellets (i.e., PDLSCs) would be fabricated in vitro in a tissue-mimicking way and then implanted into periodontal defects. We hypothesize that this novel strategy might open new options to reconstruct extended periodontal defects and then achieve the ultimate goal of predictable and complete regeneration of the periodontium.
Assuntos
Células da Medula Óssea/citologia , Ligamento Periodontal/citologia , Periodonto/fisiologia , Regeneração , Células-Tronco/citologia , Engenharia Tecidual/métodos , Humanos , Células-Tronco Mesenquimais/citologia , Doenças Periodontais/terapia , Periodonto/citologia , Transplante de Células-TroncoRESUMO
Tooth dilaceration refers to a dental anomaly characterized by an abrupt deviation in the longitudinal axis of tooth. Crown-root dilaceration is diagnosed in teeth with sharp angles at the cement-enamel junction. The greater the bending degree is, the less chance there is for successful teeth preservation and relocation. In this report, a clinical case of an impacted maxillary central incisor with severe crown-root dilacerations was described by means of an operative evaluation using three-dimensional dental computed tomography and a multidisciplinary approach that included surgical, orthodontic, endodontic, prosthetic and periodontal therapy.
Assuntos
Assistência Odontológica Integral , Incisivo/anormalidades , Planejamento de Assistência ao Paciente , Coroa do Dente/anormalidades , Raiz Dentária/anormalidades , Dente Impactado/terapia , Criança , Coroas , Seguimentos , Gengiva/patologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Masculino , Maxila , Extrusão Ortodôntica , Equipe de Assistência ao Paciente , Tratamento do Canal Radicular , Mantenedor de Espaço em Ortodontia , Tomografia Computadorizada por Raios X/métodos , Resultado do TratamentoRESUMO
OBJECTIVE: To investigate the osteoblast-like characteristics of human periodontal ligament cells affected by elastic stress in vitro, and the role of corebinding factor a 1 (cbfa1) in alveolar bone formation during orthodontic tooth movement. METHODS: Rat dig-labeled cbfa1 cDNA probe was prepared from SD rat osteoblasts cultured in vitro. Human periodontal ligament cells were cultured on the elastic bottom plate and stimulated by elastic stress using mechanical loading system for cultured cells in vitro. The expression of cbfa1 mRNA was detected by in situ hybridization method. RESULTS: Cbfa1 mRNA express in human periodontal ligament cells stimulated by elastic stress and did not express in normal human periodontal ligament cells. CONCLUSION: It is suggested that elastic stress plays a role in the differentiation process from human periodontal ligament cells to osteoblast-like cells. Cbfa1 is a transcription factor in alveolar bone remodeling during orthodontic tooth movement.
Assuntos
Proteínas de Ligação a DNA/genética , Ligamento Periodontal/metabolismo , RNA Mensageiro/análise , Fatores de Transcrição/genética , Adolescente , Animais , Células Cultivadas , Criança , Subunidades alfa de Fatores de Ligação ao Core , Elasticidade , Humanos , Ligamento Periodontal/citologia , RatosRESUMO
OBJECTIVE: To evaluate the outcome of the treatment of malocclusion with mandibular congenital missing teeth guided by Bolton index. METHODS: 26 class I and II cases (males 10, females 16) were chosen in this study. Guided by Bolton index, enamel stripping, denture and two types of tooth extraction were used in the treatment. RESULTS: Normal Bolton index was achieved and the results of treatment were satisfactory. CONCLUSIONS: Malocclusion with mandibular congenital missing teeth can be treated successfully guided by Bolton index.