Avaliação da metilação e transcrição do gene FOXP3 na periodontite crônica / Evaluation of DNA methylation and transcription of FOXP3 gene in chronic periodontitis

FOXP3 é um fator transcricional que atua principalmente nas células T reg., modulando a resposta imune e alterando o desenvolvimento e a progressão de doenças. A periodontite crônica é uma doença inflamatória polimicrobiana que resulta em danos aos tecidos periodontais, devido à interação complexa entre os periodontopatógenos e à resposta imunoinflamatória do hospedeiro. A metilação tem grande impacto no silenciamento de genes e na consequente diminuição da síntese proteica. O objetivo deste trabalho foi avaliar o perfil de metilação do FOXP3 na periodontite crônica e associá-lo a sua expressão e a parâmetros clínicos da doença periodontal. Foram coletados fragmentos de tecidos gengivais de pacientes com periodonto saudável e com periodontite crônica, sendo 30 pacientes-controle e 30 com periodontite crônica. As amostras foram submetidas à avaliação histológica, à extração de DNA e RNA, ao tratamento enzimático de identificação de metilação e ao qPCR. Na avaliação do perfil de metilação, não foi encontrada diferença estatística entre os perfis de metilação e expressão dos grupos periodontite e controle. Foi encontrada uma diferença na metilação entre os controles do gênero masculino e feminino (p=0,002) e na expressão entre o grupo periodontite de ambos os gêneros (p=0,049). No gênero masculino, a hipermetilação foi maior no grupo periodontite (p=0,037), a hipometilação (p=0,037), e a expressão do Foxp3 foi maior no grupo controle (p=0,037). Estudos adicionais são necessários para avaliar a relevância funcional desses achados.

FOXP3 is a transcriptional factor that acts mainly on T reg cells, modulating the immune response and alters the development and progression of disease. Chronic periodontitis is a polymicrobial inflammatory disease that results in damage to periodontal tissues, due to the complex interaction between periodontal pathogens and immunoinflammatory response of the host. Methylation has great impact on gene silencing and consequent reduction in protein synthesis. The aim of this study was to evaluate the FOXP3 methylation profile in chronic periodontitis and assign it to clinical parameters of periodontal disease. Fragments of gingival tissue were collected from patients with healthy periodontum (30) and patients with chronic periodontitis (30). The samples were submitted to histological evaluation, the extraction of DNA and RNA, treatment with enzymes that identify methylation and to qPCR. In assessing the methylation profile, there was no significant difference between the profiles of groups periodontitis and control. A difference in methylation was found between male and female controls (p=0,002) and in the expression between the periodontitis group of both genders (p=0,049). In the male gender, hypermthylation was higher in the periodontits group (p=0,037), and Foxp3 expression was higher in the control group (p=0,037). Additional studies are needed to assess the functional relevance of these findings.

Effect of prosthodontic planning on lateral occlusion scheme: a comparison between conventional and digital planning

Recently, digital wax-up is proposed as a tool to aid prosthodontic planning. However, there are no data about the effect of prosthodontic planning on lateral occlusion scheme. Objective : This study aims to evaluate the impact of conventional and digital prosthodontic planning on lateral occlusion scheme. Material and Methods : Dental models of 10 patients were collected. All models had Angle Class I occlusion and were undergoing prosthodontic treatment that would influence the lateral occlusion scheme. Each set of models had received both conventional wax-up and digital wax-up. In relation to the lateral occlusion scheme, the following variables were evaluated: the prevalence of the different lateral occlusion scheme, number of contacting teeth and percentage of each contacting tooth. Four excursive positions on the working side were included: 0.5, 1.0, 2.0 and 3.0 mm from the maximal intercuspation position. Results : The lateral occlusion scheme of the two wax-up models was subjected to alterations following excursion. There was a tendency for the prevalence of canine-guided occlusion to increase and for the prevalence of group function occlusion to decrease with increasing excursion. The number of contacting teeth was decreasing with the increasing magnitude of excursion. For the 0.5 mm and 1.0 mm positions, the two wax-ups had significantly greater contacts than the pre-treatment models, while at the 2.0 mm and 3.0 mm positions, all the models were similar. For all models, canines were the most commonly contacting teeth, followed by the teeth adjacent to them. No difference was observed between the two wax-ups in relation to the number of contacting teeth. Conclusion : Although the prosthodontic planning had influenced the pattern of the lateral occlusion scheme and contacts, there was no difference between the conventional and digital prosthodontic planning. .