Introdução : Diversos estudos têm investigado as diferenças dos parâmetros salivares e microbianos entre pacientes diabéticos e não diabéticos, contudo, diferenças específicas ainda não estão claras, principalmente devido aos efeitos de variáveis de confusão.Objetivo: O objetivo deste estudo caso-controle foi avaliar os parâmetros salivares e microbianos de indivíduos com doença periodontal crônica com ou sem diagnóstico de diabetes melito tipo 2.Material e método: Este estudo caso-controle incluiu 60 indivíduos com periodontite crônica, 30 diabéticos (casos) e 30 não diabéticos (controles), pareados pela severidade da doença periodontal, gênero e idade. Saliva total estimulada foi coletada de todos os voluntários para mensuração do pH salivar e fluxo salivar. Amostras bacterianas foram coletadas com pontas de papel absorvente dos sítios periodontais com maior profundidade de sondagem e perda de inserção clínica. A frequência de A. actinomycetemcomitans, P. intermedia, P. gingivalis, T. forsythia e C. rectusfoi avaliada por PCR. Os dados foram analisados estatisticamente pelo teste t de Student, Mann -Whitney e Qui-quadrado (p < 0,05).Resultado: Diabéticos apresentaram maior nível de glicose salivar e menor fluxo salivar em comparação aos não diabéticos. P. gingivalis e T. forsythiaforam os patógenos mais frequentes (p < 0,05). Frequência bacteriana não diferiu entre os casos e controles.Conclusão: A condição diabetes influenciou o fluxo e os níveis de glicose salivar. Dentro da mesma severidade da periodontite crônica, indivíduos diabéticos não mostraram maior frequência de patógenos periodontais em comparação aos seus controles.

Background: Several studies have investigated the differences in salivary parameters and microbial composition between diabetic and non-diabetic patients, however, specific differences are still not clear mainly due to the effects of confounder.Aim: The aim of this case-control study was to evaluate the salivary and microbial parameters of chronic periodontitis subjects with and without type 2 diabetes mellitus.Material and method: This case-control study included 60 chronic periodontitis subjects, 30 diabetics (case group) and 30 non-diabetics (control group), paired according to periodontitis severity, gender and age. Stimulated whole saliva was collected from all volunteers to measure the salivary pH and the salivary flow rate. Bacterial samples were collected with paper points from periodontal sites showing the deepest periodontal pocket depth associated with the highest clinical attachment loss. The frequency of A. actinomycetemcomitans, P. intermedia, P. gingivalis, T. forsythiaand C. rectuswas evaluated by PCR. Data was statistically analyzed by Student's t, Mann-Whitney and Chi-square (p<0.05).Result: Diabetic subjects showed higher salivary glucose levels and lower stimulated flow rates in comparison to non-diabetic controls. P. gingivalisand T. forsythia were the most frequent pathogens (p<0.05). Bacterial frequency did not differ between case and control groups.Conclusion: Diabetes status influenced salivary glucose levels and flow rate. Within the same severity of chronic periodontitis, diabetic subjects did not show higher frequency of periodontal pathogens in comparison to their paired controls.

Aggregatibacter actinomycetemcomitans is associated with periodontal disease, especially localized aggressive periodontitis, produces a potent leukotoxin and its distribution is influenced by ethnic characteristics of the population. Objective: Using culture and polymerase chain reaction (PCR) techniques, this study evaluated the occurrence of this microorganism and the distribution of leukotoxic strains isolated from Indians belonging to the Umutima Reservation, Mato Grosso, Brazil. MATERIAL AND METHODS: Forty-eight native Brazilians with gingivitis and 38 with chronic periodontitis, belonging to Umutina, Paresi, Bororo, Bakairi, Kayabi, Irantxe, Nambikwara and Terena ethnicities, were studied. Subgingival, supragingival and saliva samples of each patient were collected and transferred to VMGA III medium and to ultra pure Milli Q water. Bacteria were grown on TSBV agar and incubated in anaerobiosis (90% N2 + 10% CO2) at 37ºC for 72 h. The presence of the ltx promoter was determined by PCR, and a 530 bp deletion in the promoter was evaluated by using specific primers. RESULTS: A. actinomycetemcomitans was isolated from 8.33% of saliva, supragingival and subgingival samples from patients with gingivitis and from 18.42% of saliva and supragingival biofilm, and 26.32% subgingival biofilm from patients with chronic periodontitis. By PCR, the bacterial DNA was detected in 8.33% of saliva, supragingival and subgingival biofilms from patients with gingivitis and from 23.68% of saliva, 28.95% supragingival biofilm and 34.21% subgingival biofilm from patients with periodontitis. All strains were grouped as non-JP2 clones based on the absence of deletion in the leukotoxin promoter. Differences among the microbial and clinical parameters in patients were analyzed by using the Mann-Whitney, Chi-square or Fisher's exact tests. CONCLUSIONS: The present results suggest that A. actinomycetemcomitans can be related to the attachment loss in this population, but the presence of minimally leukotoxic strains, as well as its role in the pathogenesis of the periodontitis in these native Brazilians need to be further investigated.