Detection and quantification of periodontal pathogens in smokers and never-smokers with chronic periodontitis by real-time polymerase chain reaction.

BACKGROUND: The purpose of the present investigation is to compare the presence and number of periodontal pathogens in the subgingival microbiota of smokers versus never-smokers with chronic periodontitis and matched probing depths (PDs) using real-time polymerase chain reaction (RT-PCR). METHODS: Forty current smokers and 40 never-smokers, matched for age, sex, and mean PD of sampling site, were included in this investigation. A full-mouth periodontal examination was performed, and a pooled subgingival plaque sample was collected from the deepest site in each quadrant of each participant. To confirm smoking status, expired carbon monoxide (CO) concentrations were measured with a CO monitor. The presence and quantification of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola were determined using RT-PCR. RESULTS: Smokers had greater overall mean PD (P = 0.001) and attachment loss (P = 0.006) and fewer bleeding on probing sites (P = 0.001). An association was observed between smoking status and the presence of A. actinomycetemcomitans (P <0.001). The counts of A. actinomycetemcomitans (P <0.001), P. gingivalis (P = 0.042), and T. forsythia (P <0.001) were significantly higher in smokers. CONCLUSIONS: Smokers showed significantly greater amounts of P. gingivalis, A. actinomycetemcomitans, and T. forsythia than never-smokers. There was a significant association between smoking and the presence of A. actinomycetemcomitans.

Periodontitis and chronic kidney disease: a systematic review of the association of diseases and the effect of periodontal treatment on estimated glomerular filtration rate.

AIM: The aim of this systematic review (SR) was to evaluate the association between periodontitis and chronic kidney disease (CKD) and the effect of periodontal treatment (PT) on the estimated glomerular filtration rate (eGFR). METHODS: MEDLINE, EMBASE and Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched up to and including September 30, 2012 to observational (S1) and interventional (S2) studies on the association of periodontitis with CKD. Studies were considered eligible for inclusion if they reported the eGFR. Search was conducted by two independent reviewers. The methodological quality of the observational studies was assessed using the Newcastle-Ottawa Scale (NOS) adapted for this review, and the Cochrane's Collaboration risk of bias assessment tool. A random-effects odds-ratio meta-analysis was conducted to estimate the degree of association between periodontitis and CKD. RESULTS: Search strategy identified 2456 potentially eligible articles, of which four cross-sectional, one retrospective, and three interventional studies were included. Four S1, 80.0% reported some degree of association between periodontitis and CKD. Similarly, such an outcome was supported by pooled estimates (OR: 1.65, 95% Confidence Interval: 1.35, 2.01, p < 0.00001, χ(2)  = 1.70, I(2 ) = 0%). All interventional studies found positive outcomes related to treatment. CONCLUSION: There is quite consistent evidence to support the positive association between periodontitis and CKD, as well as the positive effect of PT on eGFR.

Avaliação crítica de ensaios clínicos / Critical evaluation of clinical trials

A maioria dos cirurgiões-dentistas que não estão envolvidos com ensino e pesquisa não está acostumada a ler e interpretar artigos científicos, não se sentindo assim qualificados para avaliar criticamente esta literatura. Ensaio clínico aleatório (ECA) é o tipo de estudo que fornece o mais alto nível de evidência científica em relação à eficácia e segurança de intervenções. Quando executado de forma correta, possibilita a produção de resultados com menor possibilidade de vieses. São vários os critérios adotados para classificar os diversos tipos de ECAs, e os clínicos devem conhecer as normas que norteiam a condução deste tipo de estudo, para que possam avaliá-lo criticamente. Esta revisão tem como objetivo fornecer algumas informações sobre aspectos metodológicos de ECAs, que podem auxiliar na interpretação deste tipo de estudo.

Most dentists who are not involved with teaching and research are not used to read critically scientific papers, and do not fell qualified to evaluate this sort of literature. Randomized clinical trial (RCT) is the type of study that provides the highest level of scientific evidence on efficacy and safety of a specific intervention. When correctly conduced, it is able to produce results with less possibility of bias. There are several criteria used to classify different types of RCTs, and clinicians should know the guidelines about the conduction of this type of study. This review aims to provide some information on methodological aspects of RCTs, which may assist in interpreting this type of study.