The aim of the study was to investigate the effect of xylitol, from some oral hygiene products and chewing gums, on salivary parameters variation in patients with carious disease. The study was performed on 30 patients with a medium level of carious disease, randomly divided in two groups as follows: group 1 (study group), using xylitol-based products for 30 days, and group 2 (control group), using products without xylitol. The way of administration, dose, and frequency of use were as follows: toothpaste (normal daily brushing, 3 times daily); mouthwashing (5 ml, twice daily); chewing gums (two tablets, 5 times daily), for 30 days. The assessment targeted the salivary parameters as follow: saliva microcrystallisation index (IMK), resting salivary flow rate (RSF), stimulated salivary flow rate(SSF). The results of our study confirm the improvement of salivary parameters due to the use of xylitol-based products, by the positive influence on the remineralisation capacity of saliva. The assessment method of saliva IMK represents a noninvasive, simple, informational indicator for the assessment of the remineralisation capacity of saliva.

The aim of this study was to assess the quality of the interface between dental root cement and some restorative materials used in the open sandwich technique. Standardised cavities were prepared on the buccal and oral surfaces of 30 human molars with the gingival margin situated in root cement. The teeth were randomly divided in 3 groups. Different materials combinations were used in buccal and oral cavities. In the control group, the cavities were filled only with composite resins (Filtek Z250-3M ESPE and Zmack Comp-Zermack). In the test groups the cavities were restored using an open sandwich technique as follows: in group 1 Filtek Z250 in combination with Dyract, respectively Ketac Molar Easymix; in group 2 Zmack Comp in combination with Dyract, respectively Ketac Molar. The teeth were stored in 1% methylene blue solution, for 24 hours. The samples were longitudinally sectioned through the centre of restorations and the degree of dye penetration as well as the morphology of the interface between the root cement and the restorative material were evaluated by optical microscopy and SEM. The results showed less microleakage and and adhesive failures in open sandwich restorations with Zmack Comp and Dyract combination.

The aim of this study was to evaluate and to compare the compression behavior under identical mechanical tests, of three different composite resins, by determining Young�s modulus for compression, ultimate compressive strength and ultimate compressive strain. The studied materials were: Filtek Z250 Universal Restorative, Filtek Z550 and Filtek Bulk Fill Posterior Restorative (3M ESPE, St. Paul, MN, USA). Fifteen cylindrical samples, having 6 mm in height and 5 mm in diameter, were made from each material, using plastic molds. The samples were subjected to quantitative analysis of the compression behavior after mechanical tests. The fractured fragments of the samples were subjected to qualitative surface evaluation by scanning electron microscopy. Results were statistically analyzed using one-way analysis of variance (ANOVA) with Tukey�s post hoc test. Filtek Z250 had the lowest value of Young�s modulus for compression and the results were statistically significant (p[0.05) when compared to Filtek Bulk Fill Posterior Restorative and Filtek Z550. There were no statistically significant differences between all three materials regarding ultimate compressive strength (p]0.05). The lowest value for ultimate compressive strain was recorded for Filtek Bulk Fill.

The aim of the study was to compare the marginal adaptation of three different resin-based materials used for direct restoration: hybrid composite resin (Gaenial Posterio, GC Corporation), a compomer (Dyract eXtra, Dentsply Sirona), and a giomer (Beautifil II, Shofu Dental) applied at room temperature or after preheated at preheating 50 and 60oC. Class II cavities were prepared on proximal surfaces of extracted teeth and randomly divided in 3 groups according to the material used for restoration. In each group five cavities were restored using the materials at room temperature (subgroup 1), five cavities were restored using preheated materials at 50şC (subgroup 2), and five cavities were restored using preheated materials at 60şC (subgroup 3). The teeth were stored in distilled water for 14 days and then were immersed in 2% methylene blue buffered dye solution (pH = 7) for 4 hours. The teeth were transversally cut and the sections were examined using optical microscope (Carl-Zeiss AXIO Imager A1m) at 50x magnification and the dye penetration was evaluated according to 4 scores. Decreased microleakage and fewer gap formation were recorded for all filling materials after they have been heated at 50 or 60oC. Pre-warming of resin-based materials improves the adaptation of these materials to tooth structures.

The load-bearing capacity and fracture pattern of direct inlay-retained FRC FDPs with two different cross-sectional designs of the ponticwere tested. The aim of the study was to evaluate a new fibre disposition. Two types of composites, Filtek Bulk Fill Posterior Restorative and Filtek Z250 (3M/ESPE, St. Paul, MN, USA), and one braided polyethylene fibre, Construct (Kerr, USA) were used. The results of the study suggested that the new tested disposition of the fibres prevented in some extend the delamination of the composite on buccal and facial sides of the pontic and increased the load-bearing capacity of the bridges.