Occurrence of yeasts, pseudomonads and enteric bacteria in the oral cavity of patients undergoing head and neck radiotherapy

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Antimicrobial resistance of aerobes and facultative anaerobes isolated from the oral cavity

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of sample type and collection method on Streptococcus mutans and Lactobacillus spp. counts in the oral cavity

Objectives: This study compared three methods of Streptococcus mutans and Lactobacillus spp. detection in the oral cavity: saliva swab (SS)-sample of stimulated saliva collected with swab; whole saliva (WS)-sample of 2 ml of stimulated saliva; and the dental plaque method (DP)-plaque sample of all dental surfaces.Methods: Thirty children were included in this study. In the first 15 children, the SS and WS methods were carried out before the dental plaque collection, and in the following 15, the sequence was inverted to evaluate possible interference of the methods sequence. The samples were diluted and inoculated in SB20 and Rogosa agar, respectively for S. mutans and Lactobacillus spp., at 37 degrees C for 48 h.Results: the results (cfu/mL) of S. mutans were analysed by the statistical Friedman's test. The levels of Lactobacillus spp. were analysed by descriptive statistics due to the high proportion of zero counts in the culture. In the first sequence of methods, the number of S. mutans counted for the SS method was inferior to DP and WS (P < 0.05), and the results for the WS and DP methods were similar. The detection of Lactobacillus spp. was observed just by the WS (100 %) and SS (14.3 %) methods. However, in the second experimental set the number of S. mutans detected by the DP method was similar to those of the SS and WS, however, the WS method showed higher values than SS (P < 0.05). A greater number of Lactobacillus spp. was detected by the WS method (100 %), followed by SS (55.5 %) and DP (33.3 %).Conclusions: the dental plaque collection and the sample of stimulated whole saliva presented similar results in the S. mutans count. The most suitable method to detect the Lactobacillus spp. level in the oral cavity is the stimulated whole saliva method. (c) 2004 Elsevier Ltd. All rights reserved.

Comparative Histopathological Analysis of Human Pulps after Class I Cavity Preparation with a High-Speed Air-Turbine Handpiece or Er:YAG Laser

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Candida spp. biotypes in the oral cavity of school children from different socioeconomic categories in Piracicaba - SP, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of Conventional and Resin-modified Glass-Ionomer Liner on Dentin Adhesive Interface of Class I Cavity Walls After Thermocycling

Objective: The aim of this in vitro study was to analyze the effect of glass-ionomer cement as a liner on the dentin/resin adhesive interface of lateral walls of occlusal restorations after thermocycling.Materials and Methods: Occlusal cavities were prepared in 60 human molars, divided into six groups: no liner (1 and 4); glass-ionomer cement (GIC, Ketac Molar Easymix, 3M ESPE) (2 and 5); and resin-modified glass-ionomer cement (RMGIC, Vitrebond, 3M ESPE) (3 and 6). Resin composite (Filtek Z250, 3M ESPE) was placed after application of an adhesive system (Adper Single Bond 2, 3M ESPE) that was mixed with a fluorescent reagent (Rhodamine B) to allow confocal microscopy analysis. Specimens of groups 4, 5 and 6 were thermocycled (5 degrees C-55 degrees C) with a dwell time of 30 seconds for 5000 cycles. After this period, teeth were sectioned in approximately 0.8-mm slices. One slice of each tooth was randomly selected for confocal microscopy analysis. The other slices were sectioned into 0.8 nun x 0.8 mm beams, which were submitted to microtensile testing (MPa). Data were analyzed using two-way ANOVA and Tukey test (p < 0.05).Results: There was no detectedstatistical difference on bond strength among groups (alpha < 0.05). Confocal microscopy analysis showed a higher mean gap size in group 4(12.5 mu m) and a higher percentage of marginal gaps in the thermocycled groups. The RNIGIC liner groups showed the lowest percentage of marginal gaps.Conclusions: Lining with RMGIC resulted in less gap formation at the dentin/resin adhesive interface after artificial aging. RMGIC or GIC liners did not alter the microtensile bond strength of adhesive system/resin composite to dentin on the lateral walls of Class I restorations.

Evaluation of Ultrasonic and ErCr:YSGG Laser Retrograde Cavity Preparation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Morphological alteration of peritoneal mast cells and macrophages in the mouse peritoneal cavity during the early phases of an allergic inflammatory reaction

We investigated the presence of mast cell granules in macrophages following an in vivo model of an allergic reaction. Injection of ovalbumin (100 mug) into the peritoneal cavity of sensitised mice produced a rapid (within 2 h) influx of neutrophils followed by a slower (after >4 h) eosinophil migration. Ovalbumin treatment induced a high incidence (similar to 50%) of mast cell degranulation compared to control phosphated-buffered saline-treated mice. The majority (similar to 90%) of peritoneal macrophages contained mast cell granules as early as 2 It post-ovalbumin, with lower values at later time-points, as determined by staining with Toluidine blue and Berberine sulphate. This was confirmed by electron microscopy which enabled us to identify the complex mast cell granule sub-structural components in macrophage phagosomes. In conclusion, we used histochemical and ultrastructural analyses to show that mast cell granules become internalised with macrophages during the early stages of an experimental allergic reaction. (C) 2001 Academic Press.

Frequency of Candida spp. in the Oral Cavity of Brazilian HIV-Positive Patients and Correlation with CD4 Cell Counts and Viral Load

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of consumption of probiotics on presence of enterobacteria in the oral cavity

Clinical benefits of probiotics have been clearly reported in different gastrointestinal disorders, many of them caused by enterobacteria. The oral cavity is a port of entry and can be an important reservoir of these microorganisms. This work evaluated whether consumption of probiotics was able to influence the presence of enterobacteria in the oral cavity and the specific secretory response against these microorganisms. Saliva samples of healthy individuals were collected and plated in Mac-Conkey agar. Carriers of Gram-negative, rod-shaped microorganisms in the oral cavity were selected and instructed to use the probiotic Yakult LB for 20 days. Saliva was then collected and enterobacteria species were identified using the API 20 E system and by ELISA using anti-enterobacteria IgA. The results showed reduction in the prevalence of enterobacteria, but no significant changes in enterobacterial counts (log CFU/mL; p = 0.3457). The species most frequently isolated were Enterobacter cloacae and Klebsiella oxytoca, both before and after probiotic consumption. No significant changes were observed in anti-enterobacteria IgA levels. In conclusion, probiotic consumption had some influence on enterobacterial presence in the oral cavity, but did not affect enterobacterial counts or the specific immune secretory response against them.