Radiolucent halos beneath composite restorations do not justify restoration replacement.

PURPOSE: To determine the correlation between the presence of radiolucent areas (RA) beneath composite restorations and gaps and remaining demineralized tissue (RDT). METHODS: 50 extracted teeth (sound and carious) were studied. After caries removal, cavities were filled. Artificial cavities were created and filled in the sound teeth. Samples were sectioned and analyzed with stereomicroscopy. RESULTS: Gap/RDT was observed in 38.9% [95% confidence interval (CI) =28.2-50.5] and 68.9% (95% CI = 57-78.6) of sound and carious teeth, respectively, (P = 0.001). Gap/RDT was associated with RA (P < 0.001). Sensitivity, specificity, predictive positive values (PPV), predictive negative value, and accuracy for carious teeth were 77.1% (95% CI = 63.7-87.3), 54.5% (95% CI = 33.8-74.1), 78.7% (95% CI = 65.3- 88.7), 52.2% (95% CI = 32.1-71.7), and 70% (95% CI = 58.5-79.8), and for sound teeth were 73.7% (95% CI = 62.9-82.6), 59.1% (95% CI = 47.0-70.4), 67.5% (95% CI = 56.9-76.9), 66.1% (95% CI = 53.4-77.3), and 66.9% (95% CI = 58.9-74.3). Only the PPV differed between the sound and carious teeth (P = 0.024).There was a correlation between radiolucency and gap/RDT, but a high number of false positives were found.

Effects of lactose-containing stevioside sweeteners on dental biofilm acidogenicity.

The aim of this study was to evaluate the effect of a commercial lactose-containing stevioside sweetener on biofilm acidogenicity in vivo. Nine volunteers refrained from brushing their teeth for 3 days in five phases. On the 4th day of each phase, the pH of the biofilm was measured by the "Strip method". Interproximal plaque pH was measured before and up to 60 minutes after a 10 mL mouthrinse for 1 minute with the test solutions: I - sweetener with 93% lactose and 7% stevioside; II - sweetener with 6.8% saccharin, 13.6% cyclamate, and 0.82% stevioside; III - 18% sucrose solution (positive control); IV - mineral water (negative control); and V- 93% lactose solution. The results revealed that the most pronounced pH fall was found with sucrose (positive control), followed by the 93% lactose solution, the sweetener with lactose + stevioside, the sweetener with saccharin + cyclamate + stevioside, and finally water (negative control). According to the area under the curve, the two sweeteners containing stevioside were significantly different, and the sweetener with lactose + stevioside was significantly different from water but not from sucrose. The critical pH for dentin demineralization (pH ≤ 6.5) was reached by all volunteers after rinsing with sucrose solution, lactose solution, and the stevioside + lactose sweetener. Analysis of the data suggests that lactose-containing stevioside sweeteners may be cariogenic, especially to dentin.