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Objective:: To evaluate the influence of an application technique of a glass-fiber post using self-adhesive resin cements on the push-out bond strength and the presence of bubbles in the root thirds. The cements were either applied according to the manufacturer's instruction or using a commercial delivering system (Centrix), at which the cement pastes were collected and applied after manipulation., Material and Methods:: Self-adhesive resin cements (RelyX U200/3M ESPE-U200; Maxcem Elite/Kerr-MAX; Clearfil SA Cement/Kuraray-CSA) and a conventional cement (RelyX ARC/3M ESPE-ARC) were used to cement a post and applied either based on the manufacturer's instructions or using a Centrix syringe to deliver the cements directly onto the post of choice, or directly into canal. The roots were scanned with a micro-computed tomography (μCT) and then sectioned into nine 1-mm thick slices for a push-out bond strength test. The μCT images showed the percentage of bubbles in the root thirds (cervical, medium, and apical). Data were analyzed with three-way ANOVA/Tukey (α=0.05)., Results:: Triple interaction was not significant (p>0.05). The interaction "material" vs "root third" was not significant. A significant interaction was observed between "material" vs "application technique" (p<0.05). For ARC, U200, and MAX, significantly lower percentages of bubbles were observed when the Centrix syringe delivered the cements. Equivalent percentages of voids were observed for CSA, irrespective of the application technique (p>0.05). Significantly higher bond strength was observed when the self-adhesive resin cements were applied using the Centrix delivery system, in comparison with the manufacturer's instructions (p<0.05). Bond strength varied with the root third: cervical>medium>apical (p<0.05). No correlations were found between the bond strength and voids., Conclusions:: Bond strength and voids are negatively influenced by the conventional application technique for luting fiber posts. The delivery system (Centrix) seems to produce better results when cementing fiber posts.

This study evaluated quantitatively and qualitatively the effect of the storage time of samples before the application of the cell lysis solution (CLS) for extracting DNA from buccal cells (BC). BC from the upper and lower gutter region were collected from 5 volunteers using special cytobrushes (Gentra), totaling 3 collections for each individual. In the control group (n=10), CLS was applied soon after BC collection. In the other two groups, samples were stored at room temperature (n=10) or at 4 degrees C (n=10). After CLS application, DNA was extracted according to the manufacturer's instructions (Puregene DNA Buccal Cell Kit; Gentra Systems, Inc.). The DNA obtained was evaluated by two calibrated blind examiners using spectrophotometry and analysis of DNA bands (0.8% agarose gel electrophoresis). The obtained data were submitted to one-way ANOVA. The means and standard deviations for DNA extracted under immediate, room temperature and cooling temperature conditions were 3.5+/-0.7, 3.0+/-0.6 and 4.1+/-1.8 microg, respectively (p=0.385). No significant differences were found in relation to the amount of DNA for the different storage conditions. However, in the visual analysis of the DNA bands, no trace of DNA degradation was detected when CSL was applied soon after DNA collection, while DNA bands with degradation could be observed in the other groups. Within the limitations of the study, it may be concluded that CLS should be applied soon after DNA collection in order to obtain high-quality DNA from BC.

Despite the large number of published cases about oral and maxillofacial pediatric lesions, the literature is scarce on epidemiological studies regarding the prevalence of these entities. This study retrieved oral and maxillofacial pediatric lesions from the Center of Diagnosis of Oral Diseases (CDDB) at the Dental School of the Federal University of Pelotas (UFPEL), comprising a 20-year period (1983-2002). From the total of 9,465 biopsies received in this period, 625 (6.6%) were from children aged 0 to 14 years. Regardless of the histopathological diagnosis, patient data referring to lesion location, sex and age were collected. Diagnoses were grouped in 13 categories. As much as 89% of the cases occurred in patients aged 7 to 14 years (53% in females and 47% in males). Mucocele (17.2%) was the most common type of lesion, followed by dentigerous cyst (8.6%). In the category of odontogenic tumors, odontoma was the most frequent lesion (64.2%). Malignant lesions were observed in a small section of the sample (1.2%). Generally, the results of the present study are in line with those reported in the literature concerning the most prevalent lesions in the pediatric population. Most lesions were benign, and malignant lesions were diagnosed in a very small part of the sample.

The aim of this study was to evaluate the clinical status of pulpotomy treatment with calcium hydroxide and to correlate it with the quality of restoration of the treated teeth. Patients were retrieved from the files of the Operative Dentistry clinics (FOUFPel) between 1996 and 2000. Twenty-two patients were recalled, which had 23 teeth treated with pulpotomy due to exposure by caries. Seven anterior and 16 posterior teeth composed the evaluated group, being all restored with composite resin. The age varied from 15-50 years (mean 23.9) and the follow-up mean was 34.52 months. Clinical and radiographic examinations were performed to evaluate the clinical status of treatment. The criteria used, clinically favorable and failure, were based on the following clinical exams: pulp vitality; sensitivity; and periapical alterations. The quality of the restorations was based on the USPHS criteria. Pulpotomy treatment was ranked as clinically favorable in 10 teeth (43.5%), 4 in anterior and 6 in posterior teeth. Failure was verified in 13 teeth (56.5%), 4 anterior and 9 posterior. From the group clinically favorable, 90% of the restorations were ranked as clinically satisfactory, while only 10% were unsatisfactory. In the failure group, 77.8% of the restorations were classified was unsatisfactory and 22.2% were ranked as satisfactory. The statistical analysis (Fisher´s exact test) demonstrated that there is a statistically significant association between the clinical status of pulpotomy and restoration quality (p<0.05). Within the limitation of the study, it was verified that the quality of restoration could influence the favorable clinical status of pulpotomized teeth. Randomized clinical trials are required to confirm these preliminary data.