BACKGROUND: Alveolar bone resorption is more severe in type 2 diabetes-potentiated periodontitis. The key cells responsible for bone resorption are the osteoclast and their quantity and activity are regulated by the RANK/RANKL/OPG system. One of the major RANKL-expressing sources in diseased periodontal tissue are activated B and T lymphocytes, therefore it was hypothesized that type 2 diabetes up-regulates B cell RANKL function. OBJECTIVE: The aim of this study was to compare the effect of diabetes on the ability of B and T lymphocytes to stimulate osteoclast activity. MATERIALS AND METHODS: Metabolic status (diabetic vs normal) of mice were established using either a low-fat diet (LFD) or high-fat diet (HFD). Spleen lymphocytes were harvested and purified, then cultured in different combinations with adherent mouse leukemic monocyte/macrophage cell line cells over dentin-coated wells and observed for osteoclastic activity that breaks down the dentin-coating. The area of clearance was used to represent the level of activity. RESULTS: No difference in osteoclastic activity were noted between the two metabolic statuses, between B or T cells, between lymphocyte stimulated or not. CONCLUSION: The findings counters our hypothesis, and are inconsistent with the currently available evidence. Repeat of the experiment is warranted before valid conclusion can be drawn from the data.

The efficcacy of the treatment of the endodontic-periodontal lesion was evaluated in longitudinal studies, by means through a systematic review. Bibliographic tabulation sources identified electronically by MEDLINE, from 1966 up to March, 26 of 2007 and Cochrane Library, in the same period. As search strategy one used the terms - endodontic-periodontal lesion or endodontic-periodontal lesions or endodontic periodontal lesion or endodontic periodontal lesions or endo-perio lesion or endo-perio lesions or endodontics periodontal lesion or endodontics periodontal lesions - as word-key. The studies had been selected by two copyholders, independent, that also they had determined the criteria of inclusion and exclusion. The search presented 257 related articles, being that, of these, 55 articles were of literature revision, 27 articles became related with prospectives studies, 70 studies was cases reports, 19 studies had been developed in animals and 25 had involved retrospective studies. Absence of longitudinal studies that satisfied the inclusion criteria, with sights to the analysis based on evidences was observed. However, front to applied literature was verified that the success of the treatment of the endodontic-periodontal lesions is related to the brief identification of the etiology, to the control of microbiota present, to the immunological characteristics of the individual, being that one of the strategies and possible prognostic the origin of the infectious process is associated to it. Considering the estimate of success of the clinical success of the endodontic-periodontal lesion an initial microorganisms control in the oral cavity is suggested, followed for the control of endodontical microorganisms and, to follow, the periodontal, for then carrying through the treatment. The immunological system of the individual participates actively of the process as component manager. / Avaliou-se em estudos longitudinais a eficácia do tratamento da lesão endodôntica-periodontal, por meio de revisão sistemática. Utilizou-se de fontes de catalogação bibliográfica identificadas eletronicamente por MEDLINE, a partir de 1966 até 26 de março de 2007 e Cochrane Library, no mesmo período. Como estratégia de busca utilizou-se os termos endodontic-periodontal lesion or endodontic-periodontal lesions or endodontic periodontal lesion or endodontic periodontal lesions or endo-perio lesion or endo-perio lesions or endodontics periodontal lesion or endodontics periodontal lesions como palavras-chave. Os estudos foram selecionados por dois revisores, independentes, que também determinaram os critérios de inclusão e exclusão. A busca apresentou 257 artigos relacionados, sendo que, destes, 55 artigos eram de revisão de literatura, 27 artigos relacionavam-se com estudos prospectivos, 70 estudos eram relatos de casos clínicos, 19 estudos foram desenvolvidos em animais e 25 envolveram estudos retrospectivos. Observou-se ausência de estudos longitudinais que satisfizessem os critérios de inclusão, com vistas à análise baseada em evidências. Contudo, frente à literatura aplicada verificou-se que o sucesso do tratamento das lesões endodônticas-periodontais está relacionado à breve identificação da etiologia, ao controle da microbiota presente, às características imunológicas do indivíduo, sendo que uma das estratégias e o possível prognóstico vincula-se à origem do processo infeccioso (endodôntico ou periodontal). Considerando a estimativa de êxito do sucesso clínico da lesão endodôntica-periodontal sugere-se um controle microbiano inicial na cavidade bucal, seguido pelo controle da microbiota endodôntica e, a seguir, a periodontal, para então realizar o tratamento. O sistema imunológico do indivíduo participa ativamente do processo como componente gerenciador. / Mestre em Odontologia

INTRODUCTION: Utilization of rapid maxillary expansion (RME) is common for the correction of sagittal discrepancies in orthodontic treatment. RME appliances will transmit a compressive force to the periodontal support structures. This resultant force can lead to resorption of the dento-alveolar structures leading to unwanted dental movements. The purpose of this retrospective study was to compare changes from a periodontal and root resorption perspective by means of computer tomography with tooth-borne and bonded expanders. METHODS: The sample comprised of cone beam computed tomography and spiral CT images of 41 subjects, 12 to 17 years old, with unilateral or bilateral posterior crossbites. 20 subjects treated previously with a bonded expander and 21 with a banded expander. Pre and post-treatment images were digitized and landmarks were identified to measure buccal and lingual cortex thickness, alveolar height, root length and angulation by means of a computerized method. RESULTS: RME with banded and bonded expanders have similar effects from periodontal and root resorption perspectives. Changes include increasing thickness of lingual alveolar bone 0.2 to 0.7 mm, decreases in buccal bone width 0.1 to 0.5 mm; and decreases in alveolar height 0.1 to 0.9 mm and root length 0.3 to 1.0mm of each support teeth. CONCLUSIONS: RME with banded and bonded expanders exhibited similar changes post-expansion and these variables should not play a role in selection of the type of device.