Eduardo Muniz Barretto Tinoco

Detection of cytotoxin genotypes of Helicobacter pylori in stomach, saliva and dental plaque

BACKGROUNDnThe aim of this study was to detect the presence of Helicobacter pylori and its virulent cagA genes in the oral cavity of individuals with upper gastric diseases. Sixty-two individuals (42+/-2.3 years) with dispepsy symptoms, referred for gastroscopy and who were H. pylori positive in the gastric biopsy, were recruited and separated in two groups: case group-individuals with gastric disease (n = 30); control group-individuals with no gastric disease (n = 32); saliva, dental plaque and biopsy samples were collected from all individuals. Oral and biopsy samples were analyzed by PCR using specific primers for H. pylori 16S ribosomal and cagA genes. PCR products were sequenced for DNA homology confirmation. H. pylori was detected neither in dental plaque nor in saliva in the control group. In the case group H. pylori DNA was detected in 16/30 (53.3%) saliva samples and in 11/30 (36.6%) dental plaque samples. The cagA gene was detected in 13/30 (43.3%) gastric biopsies, in 7/16 (43.8%) saliva samples, and in 3/11 (27.3%) dental plaque samples. Eighteen (60.0%) individuals in the case group were H. pylori positive both in oral and biopsy samples, and 8 (26.6%) of those were positive for cagA-H. pylori DNA. H. pylori and its virulent clone showed a higher prevalence in the oral cavity of individuals in the case group than in the control group (p < 0.05). Our results suggest that dental plaque and saliva may serve as temporary reservoir for H. pylori and its virulent cagA variant in individuals with gastric disease.

Helicobacter pylori transiently in the mouth may participate in the transmission of infection

Helicobacter pylori infection is associated with peptic ulcer and gastric carcinoma. The oral cavity may be a reservoir for H. pylori; however, the results of studies on this subject are controversial. We employed single-step and nested polymerase chain reactions (PCR) to detect the presence of the vacA, ureA and 16S rDNA genes of H. pylori in the stomach, saliva and dental plaque of 30 subjects. The results were confirmed by sequencing. Nested 16S rDNA and ureA amplification was achieved in 80% of gastric, 30% of saliva and 20% of dental plaque specimens. Sequencing of 10, seven and four 16S rDNA products from stomach, saliva and dental plaque, respectively, showed > 99% identity with H. pylori. Sequencing of the other four oral cavity PCR products showed similarity with Campylobacter and Wolinella species. Additionally, the vacA genotype identified in the samples of different sites was the same within a given subject.H. pylori may be found in the oral cavity of patients with gastric infection, thus it could be a source of transmission. However, results obtained with detection methods based only on PCR should be interpreted with caution because other microorganisms that are phylogenetically very close to H. pylori are also present in the mouth.

Prevalence of dental trauma in Pan American Games athletes

The aim of this cross-sectional epidemiological survey was to assess the prevalence of dental trauma in athletes representing 42 countries competing at the most recent Pan American Games (XV Pan Am) held in Rio de Janeiro, Brazil in July of 2007, and to determine prior use and type of mouthguard among this group of athletes. The examiners participated in standardization and calibration training sessions before the field phase began. Invitations were sent to >5500 participating athletes competing in 41 sports and to the Medical Committee of the Pan American Sports Organization before and during the XV PAN. A convenience sample of 409 athletes was recruited. After signing an informed consent, all athletes answered a questionnaire. Data were collected at the clinical examination and recorded on a specific trauma form. The mean age of the athletes was 24.4 +/- 5.3 years. Males comprised 55% of the sample; females 45%. The prevalence of dental trauma among the athletes was 49.6% (n = 203) with no gender-based differences. Most of these injuries (63.6%) were related to activities during training or competition. Sports with the highest injury prevalence were wrestling (83.3%), boxing (73.7%), basketball (70.6%) and karate (60%). The most common injury was enamel fracture (39.8%); root fracture was the least common (0.4%). The teeth most affected were the maxillary permanent central incisors (n = 113), followed by the mandibular central incisors (n = 19). Based on the results of this study, nearly one-half of the subjects had experienced previous dental trauma; the majority related to sports activities. Furthermore, only 17% of the athletes reported prior mouthguard use; the most frequent mouthguards reported were boil-and-bite. These results suggest the importance of enhanced educational efforts and the use of properly fitted mouthguards to reduce dental trauma among athletes in international sports competition, especially in sports where mouthguards are not mandatory.

Presence of Helicobacter pylori in supragingival dental plaque of individuals with periodontal disease and upper gastric diseases

BACKGROUNDnHelicobacter pylori is a Gram-negative microorganism which is able to colonize the gastric mucosa and is associated with peptic ulcer, gastric carcinoma, and gastric mucosa-associated lymphoid tissue lymphoma. Several studies have detected this bacterium in the oral cavity, suggesting it as a potential reservoir. The aim of this study was to investigate the presence of H. pylori in the oral cavity of individuals with periodontal disease and gastric diseases.nnnMETHODSn115 individuals, with mean age 49.6 (±5.8) years, were divided in 4 groups: (A) with gastric diseases and periodontal disease; (B) with gastric diseases and no periodontal disease; (C) without gastric diseases and without periodontal disease, (D) without gastric diseases and with periodontal disease. Supra and subgingival plaque samples were collected from posterior teeth of the individuals with sterile paper points, and prepared for Polymerase Chain Reaction analysis. Fishers exact test was used for detecting statistical differences between groups (p<0.05).nnnRESULTSnH. pylori was detected in supragingival plaque of 9/36 (25%) of group A, 1/31 (0.3%) of group B, 0 (0%) of group C and 3/36 (8.3%) of group D. No subgingival samples were positive for H. pylori. There was a statistically higher prevalence of H. pylori in groups A and D when compared to B and C (p<0.05).nnnCONCLUSIONnH. pylori was detected in the supragingival plaque, but not in the subgingival plaque, of individuals with periodontal disease and upper gastric diseases. There was an association between the supragingival colonization of H. pylori and oral hygiene parameters such as the presence of plaque and gingival bleeding.

Manifestações bucais em pacientes submetidos à quimioterapia

Several changes in the oral cavity due to chemotherapy can be observed and can lead to important systemic complications, increasing the time of the patient in hospital and the costs of the treatment as well as affect the quality of life of the patients. The aim of this study was to assess the oral manifestation in patients treated with chemotherapy according to sex, age and tumor type. Data was collected in an oncology hospital in Juiz de Fora, Minas Gerais State, from patients records that were submitted to oncologic treatment. It was possible to verify that mucositis, associated or not to other type of lesions, was the most common lesion in both sex of all ages (15.5%). Xerostomia and other lesions, such as Candida infection and aphthous lesions, were also present. It is possible to improve the quality of life of the patient during and after anti-neoplastic therapies through a protocol of odontological assistance that includes changes of the oral environment previous to chemotherapy such as profilaxis, caries removal, treatment of periodontal and periapical lesions, oral hygiene instructions, diet orientation and laser therapy. It is very important the insertion of the dentist in the oncologic medical team for the early diagnosis of the oral manifestation and follow-up during treatment time.

The effect of periodontal therapy on cardiovascular risk markers: a 6‐month randomized clinical trial

AIMnTo determine the influence of non-surgical mechanical periodontal treatment on inflammatory markers related to risk for cardiovascular disease.nnnMATERIAL AND METHODSnA total of 64 patients with severe chronic periodontitis was randomly subjected to immediately periodontal treatment (test group, nxa0=xa032) or delayed periodontal treatment, without treatment during the study period (control group, nxa0=xa032). Clinical periodontal and laboratory examinations were performed at baseline (T0), 2xa0months (T2), and 6xa0months (T6) after the initial examinations (Control group) or completion of periodontal treatment (Test group).nnnRESULTSnAfter 2xa0months of periodontal treatment there was a significant reduction of erythrocyte sedimentation rate (ESR) and triglycerides (pxa0=xa00.002, pxa0=xa00.004, respectively) in the test group. Median values of C-reactive protein, ESR, total cholesterol, and triglycerides were reduced after 6xa0month of periodontal treatment in the test group (pxa0<xa00.001, pxa0<xa00.001, pxa0<xa00.001, and pxa0=xa00.015, respectively).nnnCONCLUSIONSnThe non-surgical periodontal treatment was effective in reducing the levels of systemic inflammation markers and improved the lipid profile in subjects with severe chronic periodontitis.

Time‐Dependent Changes in Fresh‐Frozen Bone Block Grafts: Tomographic, Histologic, and Histomorphometric Findings

BACKGROUNDnBone allografts have shown satisfactory clinical results in alveolar ridge reconstructions. However, the process of incorporation and the resorption rates of these grafts are not yet fully understood.nnnPURPOSEnThe aim of this study was to use computed tomography (CT), histology, and histomorphometry to assess the time-dependent rates of resorption and incorporation of fresh-frozen bone allografts.nnnMATERIALS AND METHODSnTwenty-four patients underwent alveolar ridge reconstruction with bone block allografts and were randomly allocated to three groups with different graft healing periods (4, 6, or 8 months) before implant placement. To assess the resorption rates, CT scans were acquired within 7 days after bone graft surgery and at the end of the period. Graft samples were collected and sent for histological and histomorphometric analyses.nnnRESULTSnThe graft resorption mean rates were 50.78%u2009±u200910.43, 32.77%u2009±u20097.84, and 13.02%u2009±u20093.86 for the 4-, 6-, and 8-month groups, respectively, and were significantly different among the three groups. Newly formed bone with osteocytes near the grafted bone was observed in all three groups. The number of osteocytes was significantly lower at 4 months. Grafted bone remains were significantly higher in the shortest period of time. All of the grafts showed large amounts of calcified tissue.nnnCONCLUSIONSnAll three groups showed new bone formation and different bone resorption rates. Graft healing periods of 4 months showed less graft resorption and seemed to be the most favorable for implant placement. Healing periods of 8 months showed the largest rate of graft resorption, which could render the grafts unfavorable for implant placement.

Epidemiological evaluation of apical periodontitis prevalence in an urban Brazilian population

The present study aimed to assess the prevalence of apical periodontitis (AP) in an urban Brazilian population according to gender, age group and tooth type. Data were collected from clinical files containing the medical and dental histories and periapical radiographs of 1,126 patients treated at the School of Dentistry at Universidade do Estado do Rio de Janeiro between March 2000 and December 2010. A total of 15,724 periapical radiographs were evaluated. All the radiographs were evaluated by two independent, previously calibrated endodontists (kappa = 0.88). Periapical areas on the radiographs were classified as N (normal) or AR (apical radiolucency). The frequency of AP and the 95% Confidence Interval (95%CI) were calculated according to gender, age group and tooth type. Differences between groups were calculated using the Z-test at a significance level of 5% (p < 0.05). AP was present in 7.87% of the samples, with 16.70% occurring on previously endodontically treated teeth and 44.65% occurring on teeth referred for endodontic treatment (TR-RCT). The frequency of AP was higher among females (64%) than among males (35%). The central and lateral maxillary incisors were the most frequently affected teeth. The frequency of AP was higher among individuals between 30 and 49 years of age. In this population, AP was more prevalent among females and among individuals between 30 and 49 years of age, and the central and lateral maxillary incisors were the most frequently affected teeth.

Higher levels of salivary MUC5B and MUC7 in individuals with gastric diseases who harbor Helicobacter pylori

OBJECTIVEnThe aim of the present study was to assess the salivary levels of MUC5B and MUC7 in individuals with dyspeptic disease and Helicobacter pylori (H. pylori) in the stomach, compared to individuals without dyspeptic disease.nnnMETHODSn30 individuals with dyspeptic disease, who underwent endoscopy for upper gastrointestinal complaints at Hospital Pedro Ernesto-RJ, Brasil and tested positive for H. pylori, and 23 controls with no dyspeptic disease, with mean age 53.5+/-4.4 years, were included in the study. Saliva samples and 3 antral biopsy were taken for PCR analysis and histologic examination. In addition, saliva samples were tested by ELISA with F2 monoclonal antibody and EU7A antibody against MUC7, to determine MUC5B and MUC7 levels, prior to endoscopic examination. The expression pattern of the proteins was quantified by comparison to a pooled saliva sample of 19 healthy volunteers.nnnRESULTSnMUC5B and MUC7 salivary levels were higher in the individuals with dyspeptic disease than in controls (p<0.0001). 33.3% (9/30) of the dyspeptic individuals and 0% of the controls had H. pylori in the oral cavity.nnnCONCLUSIONSnIndividuals with gastric diseases, with H. pylori in the stomach, showed higher levels of salivary H. pylori receptors-MUC5B and MUC7-than individuals without gastric diseases. These results suggest that higher levels of specific salivary mucins could be useful as risk indicators for infection by H. pylori.

Prophage induction in lysogenic Aggregatibacter actinomycetemcomitans cells co-cultured with human gingival fibroblasts, and its effect on leukotoxin release

Lysogeny is common among strains of the periodontal pathogen Aggregatibacter actinomycetemcomitans. Since lysogenic induction is known to result in the increased synthesis and release of bacterial toxins from lysogens, it would be important to elucidate the conditions under which induction of these bacteria may occur. Co-cultures of A. actinomycetemcomitans strains (either lysogenic or non-lysogenic) and human cells (either gingival fibroblasts or pharyngeal epithelial cells) were prepared. Following incubation, bacteriophage titers of up to 6.2 × 10(7) pfu/ml were detected in the cell-free, spent culture media from the co-cultures of the lysogenic A. actinomycetemcomitans strains and the fibroblasts. Little (maximum of 2 × 10(0) pfu/ml) or no titers of phage could be detected in the mono-cultures of the lysogenic A. actinomycetemcomitans strains alone. In contrast, no phage were detectable in the cell-free spent culture media of the lysogens cocultured with the epithelial cells. Futhermore, co-culture of the A. actinomycetemcomitans lysogens with the fibroblasts resulted in enhanced release of the A. actinomycetemcomitans leukotoxin into the culture medium, in comparison with the spent culture media from mono-cultures of the lysogens alone. These results are consistent with the concept that interaction with fibroblasts may mediate prophage induction in lysogenic strains of A. actinomycetemcomitans, and that leukotoxin release is greatly augmented following induction of the lysogens.