The aim of the present cross-sectional investigation was to evaluate percentage of bone loss in patients who had been one year under periodontal maintenance at the Department of Periodontology, Faculty of Dentistry, University of São Paulo by radiographic analysis. Complete sets of periapical radiographs provided data regarding percentage of alveolar bone loss, which was correlated with arches, tooth group and proximal sites. The sample consisted of 27 men and 53 women ranging in age from 16 to 85 years (mean: 48.3 years). A total of 1,120 periapical radiographs (1,970 teeth) were digitized and analyzed with the Image Tool^® software (University of Texas Health Science Center). Bone loss was defined as when the distance between the cemento-enamel junction and the alveolar bone crest was greater than 2 mm. Two examiners (p<0.0001) performed radiographic measurements of bone loss. The Greenhouse-Geisser normality test and a univariate analysis of variance were used for statistical analysis. Mean bone loss was 20.60% (±12.12). The highest level of bone loss was observed on the distal surface and in the upper arch, as well as in the upper incisors and molars.

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The purpose of this study was to investigate the effect of cranberry polyphenol fraction on mutans streptococci. Hydrophobicity is an important factor in the adherence of bacteria to the tooth surface. We found that cranberry polyphenol fraction significantly decreased the hydrophobicity of Streptococcus sobrinus 6715, Streptococcus mutans MT8148R and JC2 in a dose-dependent manner (p<0.05). Biofilm formation by S. sobrinus 6715 and S. mutans MT8148R was inhibited by 100 μg/ml cranberry polyphenol fraction (p<0.01). When dosage was increased to 500 μg/ml, biofilm formation by S. mutans JC2 was significantly inhibited (p<0.05). Addition of 500 μg/ml cranberry polyphenol fraction to medium inhibited growth of S. mutans MT8148R compared with the control (p<0.05).

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Evaluation of swallowing has been made possible by cine-Magnetic resonance (MR) imaging with high time resolution. However, the spatial resolution in cine-MR imaging remains inadequate for the detection of anatomical structures. Therefore, it is necessary to refer to static MR images in conjunction with cine-MR imaging. The aim of this study was to determine which MR parameters were appropriate for static imaging of the anatomical structures involved in swallowing. MR imaging was carried out, and T1-weighted, T2-weighted and proton-density-weighted MR images were obtained in the sagittal plane in 5 healthy volunteers. Each image was evaluated for anatomic landmark clarity by 3 oral radiologists. The anatomic landmarks selected were the lip, tip of tongue, center of tongue, tongue base, soft palate and epiglottis. Differences in clarity among 3 imaging modalities were evaluated. A 3-point score rating system was used. The results showed that lower TE sequences, i.e., either T1-weighted or proton-density-weighted images, were the most suitable for use in conjunction with cine-MR imaging in diagnosing swallowing disorders.

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The objective of this in vitro study was to evaluate demineralization around restorations. Class V preparations were made on the buccal and lingual surfaces of each tooth. TPH (Group 1), Fuji II LC (Group 2), Tetric (Group 3), Dyract (Group 4), GS 80 (Group 5) and Chelon Fil (Group 6) were randomly placed in equal numbers of teeth. The teeth were submitted to a pH-cycling model associated with a thermocycling model. Sections were made and the specimens were examined for the presence of demineralization under polarized light microscopy. Demineralization was significantly reduced with Chelon Fil (Group 6). Furthermore, a similar inhibitory effect on the development of demineralization was observed in Groups 2, 4 and 5.

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