Effect of four bleaching regimens on color changes and microhardness of dental nanofilled composite.

Objective. The purpose of this study was to compare the color changes and microhardness of a nanocomposite after four bleaching regimens. Materials. Twenty-five specimens (n = 25) were made with a nanocomposite resin (Filtek Supreme XT). The specimens were divided into five groups equally (n = 5): bleaching groups and control group, as follows: G1: artificial saliva at 37 degrees C; (control) G2: hydrogen peroxide (HP) at 7%; G3: hydrogen peroxide (HP) at 35%; G4: carbamide peroxide (CP) at 10%; G5: carbamide peroxide (CP) 35%. Color measurements were made with spectrophotometer using CIELAB color scale. The Vickers hardness (VHN) measurements were performed at the top surface. The data were analyzed with two-way Analysis of Variance. Results. DeltaE and VHN mean values into the groups were not statistically different, however, the VHN mean values before and after storage and bleaching showed statistically significant differences. Conclusion. Nanocomposite samples showed no significant alteration (color and microhardness) after bleaching. Thus, no replacement of restorations is required after bleaching.

Reproducibility and validity of self-perceived oral health conditions.

The reproducibility and validity of self-perceived periodontal, dental, and temporomandibular joint (TMJ) conditions were investigated. A questionnaire was applied in interview to 200 adults aged from 35 to 44, who were attending as casual patients at Araraquara School of Dentistry, São Paulo State University, São Paulo, Brazil. Clinical examination was based on the guidelines of the World Health Organization manual. The interview and the clinical examination were performed in two occasions, by a calibrated examiner. Reproducibility and validity were, respectively, verified by kappa statistics (kappa) and sensitivity (Sen) and specificity (Spec) values, having clinical examination as the validation criterion. The results showed an almost perfect agreement for self-perceived TMJ (kappa = 0.85) and periodontal conditions (kappa = 0.81), and it was substantial for dental condition (kappa = 0.69). Reproducibility according to clinical examination showed good results (kappa = 0.73 for CPI index, kappa = 0.96 for dental caries, and kappa = 0.74 for TMJ conditions). Sensitivity and specificity values were higher for self-perceived dental (Sen = 0.84, Spec = 1.0) and TMJ conditions (Sen = 1.0, Spec = 0.8). With regard to periodontal condition, specificity was low (0.43), although sensitivity was very high (1.0). Self-perceived oral health was reliable for the examined conditions. Validity was good to detect dental conditions and TMJ disorders, and it was more sensitive than specific to detect the presence of periodontal disease.

Validity and reproducibility of a laser fluorescence system for detecting the activity of white-spot lesions on free smooth surfaces in vivo.

The aim of the study was to determine the reproducibility and validity of DIAGNOdent in detecting active and arrested caries lesions on free smooth surfaces. Volunteers were selected from state schools of Piracicaba, São Paulo, Brazil. Overall, 220 lesions were clinically examined. Two specially trained ('calibrated') examiners performed both clinical and laser evaluations independently, and after a 1-week interval, the examinations were repeated. The intra-examiner agreement for the laser evaluation was substantial (kappa(ex1) = 0.79, kappa(ex2) = 0.71). There was almost perfect agreement between the two examiners for the clinical examination (kappa(ex1) = 0.95, kappa(ex2) = 0.85). The inter-examiner agreement showed substantial reproducibility (kappa = 0.77) for the laser examination and almost perfect agreement (kappa = 0.85) for the clinical evaluation. The validation criterion was the clinical examination of white spots, recorded as active or arrested. The sensitivity was 0.72 and the specificity was 0.73, which indicates that the DIAGNOdent was a good auxiliary method for detecting incipient caries lesions on free smooth surfaces. The utilization of both methods can improve the efficacy of caries diagnosis.