ABSTRACT
Melatonin referred as the hormone of darkness is mainly secreted by pineal gland, its levels being elevated during night and low during the day. The effects of melatonin on insulin secretion are mediated through the melatonin receptors (MT1 and MT2). It decreases insulin secretion by inhibiting cAMP and cGMP pathways but activates the phospholipaseC/IP3 pathway, which mobilizes Ca2+from organelles and, consequently increases insulin secretion. Both in vivo and in vitro, insulin secretion by the pancreatic islets in a circadian manner, is due to the melatonin action on the melatonin receptors inducing a phase shift in the cells. Melatonin may be involved in the genesis of diabetes as a reduction in melatonin levels and a functional interrelationship between melatonin and insulin was observed in diabetic patients. Evidences from experimental studies proved that melatonin induces production of insulin growth factor and promotes insulin receptor tyrosine phosphorylation. The disturbance of internal circadian system induces glucose intolerance and insulin resistance, which could be restored by melatonin supplementation. Therefore, the presence of melatonin receptors on human pancreatic islets may have an impact on pharmacotherapy of type 2 diabetes.
Subject(s)
Animals , Humans , /metabolism , Melatonin/physiology , Circadian Rhythm/physiology , /etiology , Glucose/metabolism , Insulin-Secreting Cells/metabolism , Insulin , Melatonin/pharmacology , Polymorphism, Genetic , Receptors, Melatonin/physiology , Signal Transduction/physiologyABSTRACT
Introdução / Atualmente, na Odontologia, vem ocorrendo um aumento no número de pacientes adultos, com dentição mutilada ou periodontalmente comprometida, que estão à procura de tratamento ortodôntico. Uma adequada combinação entre o tratamento periodontal e o ortodôntico permite que uma dentição saudável e com função adequada seja restabelecida. / Objetivo / Apresentar o tratamento, combinando o retratamento ortodôntico e o tratamento periodontal, de uma paciente de 27 anos de idade, com: incisivos superiores e inferiores vestibularizados; ausência do primeiro e do terceiro molares superiores esquerdos, primeiro e terceiro molares inferiores direitos, e primeiro molar inferior esquerdo; presença de mobilidade dentária grau III nos incisivos centrais inferiores, em decorrência de doença periodontal; e perda óssea horizontal moderada e generalizada. / Resultados / A saúde periodontal foi restabelecida por meio de raspagem e alisamento radicular, realizados antes do tratamento ortodôntico. O tratamento ortodôntico ativo com sistema MBT foi finalizado em um período de 18 meses. / Conclusão / Com esse estudo, demonstramos que a combinação do tratamento ortodôntico e do tratamento periodontal, por meio de uma abordagem interdisciplinar, pode melhorar a função mastigatória do paciente, assim como sua estética, oclusão e a condição periodontal.
Subject(s)
Humans , Female , Adult , Malocclusion, Angle Class II/therapy , Orthodontic Space Closure , Periodontitis/therapy , Patient Care Planning/standards , Patient Acceptance of Health Care , Patient Satisfaction , RetreatmentABSTRACT
Purpose: This study was designed to evaluate the buccal corridor in smile esthetics and to correlate it with underlying hard tissues. Materials and Methods: Posed smiling frontal photographs, digital posterior-anterior (PA) cephalograms, and study models of 25 males and 25 females in age range of 18-25 years were taken. Photographs were evaluated for smile esthetics by eight orthodontists, eight plastic surgeons, eight beauticians and eight lay people to group them into three groups with least attractive, average and attractive smile and buccal corridor width was measured. Digital PA cephalograms were transferred on Nemo-tech software for frontal facial analysis. Intercanine and intermolar widths were measured on upper study model with the help of a digital calliper. Results: The buccal corridor width was least in attractive smile group and maximum in least attractive smile group. The buccal corridor width had a negligible correlation with hard tissues and a mild to moderate inverse correlation with intercanine and intermolar widths within the groups. Conclusion: As the amount of buccal corridor display was increased, smiling images were scored less attractive by the evaluators. The buccal corridor is not influenced by underlying skeletal hard tissues but have mild to moderate inverse correlation with the intercanine and intermolar width.