No abstract

This study evaluated the reduction of denture stomatitis and the antimicrobial activity of 0.05% sodium hypochlorite opposed to Candida albicans and Streptococcus mutans (SGM) when associated with brushing complete dentures with coconut soap. The mucosal characteristics were evaluated according to Newton's classification at baseline, after cleansing the dentures with coconut soap for 15 days in group 1 (nine patients). In the other group (19 patients) the analysis were made before and after cleansing the dentures with coconut soap and with disinfection in a soak solution of 0.05% sodium hypochlorite for 10 min during 15 days. Microbiological tests were used to isolate C. albicans and SGM. Mann-Whitney and Wilcoxon tests were used to compare the mucosal characteristics and Fisher test and McNemar test to compare C. albicans and SGM levels. Statistical analysis at the 95% confidence level (P < 0.05) showed that: (i) the association of coconut soap and 0.05% sodium hypochlorite significantly reduced clinical signs of denture stomatitis, (ii) C. albicans did not reduce in counts, (iii) SGM were reduced but not significantly and (iv) the association of coconut soap and 0.5% sodium hypochlorite was effective in controlling denture biofilm.

No abstract

This study evaluated the fracture resistance of weakened roots restored with glass fiber posts, composite resin cores and complete metal crowns. Thirty maxillary canines were randomly divided into 3 groups of 10 teeth each: teeth without weakened roots (control); teeth with partially weakened roots (PWR) and teeth with and largely weakened roots (LWR). The control group was restored with glass fiber posts and a composite resin core. Teeth in the PWR and LWR groups were flared internally to standardized dimensions in order to simulate root weakness. Thereafter, the roots were partially filled with composite resin and restored in the same way as in the control group. The specimens were exposed to 250,000 cycles in a controlled chewing simulator. All intact specimens were subjected to a static load (N) in a universal testing machine at 45 degrees to the long axis of the tooth until failure. Data were analyzed by one-way ANOVA and Dunnett's test for multiple comparisons (p=0.05). There were statistically significant difference differences (p<0.01) among the groups (control group = 566.73 N; PWR = 409.64 N; and LWR = 410.91 N), with significantly higher fracture strength for the control group. There was no statistically significant difference (p>0.05) between the weakened groups. The results of this study showed that thicker root dentin walls significantly increase the fracture resistance of endodontically treated teeth.

The fracture strength of teeth with cast metallic posts, teeth with anatomical posts or teeth with glass fibre posts combined with accessory posts was similar. All teeth restored with cast metallic posts presented fractures and were unfavourable to maintenance of the remaining tooth structure. Teeth with fibre posts (Groups 2 to 5) presented variable fracture modes; however, the maximum percentage of unfavourable fractures was 30%.