The aim of this study was to evaluate the microhardness Rockwell and Young s modulus of a new nano-hybrid and nano-fill composite resins exposed to corrosive media. The study was performed on two composite resins, one nano-hybrid and one nano-fill, enamel, dentine, translucent, respectively body shade, of which were made 20 samples (25.0 � 0.1 mm lengths, 10.0 � 0.1 mm widths and 3.0 � 0.1 mm thicknesses), which were immersed in mouthwash for 1 minute per day for 10 days, the rest of the time being stored in artificial saliva. Measurements of Rockwell microhardness and Young�s modulus on samples were made between on the first day, after 6 days and 10 days of immersion in mouthwash comparative with 0 day. The results showed that after immersion in the corrosive environment, both materials had the hardness values changed, but medium values of Rockwell microhardness to nano-fill composite resin were higher than nano-hybride. At the nano-hybride composite resin, it was observed that the enamel and clear translucent groups had the mean values increased after the first day of exposure to mouthwash, compared to the dentine group, which showed a higher mean value after 6 days. At the nano-fill composite resin, for the enamel and body groups were obtained the higher values of HRC after 10 days. For the dentine group, after 6 days, Filtek Ultimate showed the same variation as Harmonize dentine shade. Harmonize composite resin showed higher values of Rockwell microhardness and Young�s modulus for all study groups compared to Filtek Ultimate.

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The aim of study was to evaluate the accuracy of the near-infrared light transillumination technique used in the detection of the proximal incipient dental caries. The study was performed on 12 medium caries risk subjects (mean age of 26.5). A total number of 312 proximal dental surfaces from the posterior dental group were included in the study. All the proximal surfaces, which had not been restored, or unaffected by cavitated dental caries, were assessed by a near-infrared transillumination camera system using light with a 780nm wavelength (DIAGNOcam, KaVO). Bitewing radiographies were performed for all patients included in study. Visual and tactile examination after tooth separation was performed as gold standard to detect the incipient proximal dental caries (ICDAS scores 02 and 03). Statistical analysis using Chi-square test was performed to compare the diagnostic performance of near-infrared light transillumination and the bitewing radiography. Near-infrared light transillumination showed higher sensitivity (81.80%) when compared to bitewing radiography (65.90%) to detect the non-cavitated proximal enamel caries (ICDAS score 02). Near-infrared light transillumination method showed higher sensitivity (100%) when compared to bitewing radiography (81.50%) to detect the incipient cavitated proximal enamel caries (ICDAS score 03). Specificity values for proximal incipient dental caries (ICDAS codes 02 and 03) were 95.03% for near-infrared light transillumination and 99.18% for bitewing radiography. DIAGNOcam (KaVO) is a reliable tool with high diagnostic accuracy of the incipient dental caries localized on proximal surfaces of the posterior dental group.