Aim To examine the potential systemic toxicity of nanostructured materials based on calcium silicate and calcium aluminate, for potential application in Dentistry. Methodology Twenty‐four Albino Wistar rats aged 2 months were used as an in vivo animal model for subcutaneous implantation of the investigated materials, placed in polyethylene tubes. Thirty days after implantation, the livers of the rats were analysed and following histological and stereological parameters were evaluated for volume density of hepatocytes and blood sinusoids, number and numerical density of hepatocytes, surface of hepatocytes and their nucleuses, nucleocytoplasmic ratio and mitotic index of hepatocytes. Stereological measurements were achieved using Cavalieri's principle, with grid P2 and unbiased analysis. Additionally, immunohistochemistry studies were performed to further analyse changes in liver tissue. Several haematological and biochemical parameters of blood of experimental animals were also analysed, as well as local tissue reactions around the implants. Statistical analysis was performed using parametric (anova and t‐test) and nonparametric tests (Kruskal–Wallis and Mann–Whitney U‐test) depending on data distribution. Results Implanted dental cements led to an increase in stereological and histological parameters in liver tissue compared to control rats. Although the investigated parameters mostly showed significant differences between control and experimental animals, the liver tissue of the experimental animals did not have visible signs of pathological changes. This was supported by the analysis of blood parameters which were not significantly different between control and experimental animals. Also, the subcutaneous tissues had minimal inflammatory reactions. Immunohistochemistry studies revealed that nanostructured materials induced proliferation of hepatocytes, but that the immunological response to the materials was not strong enough to induce proliferation of immunoreactive cells in liver in the observed time period. Conclusions This study was performed as a contribution to the attestation of the biocompatibility of dental cements based on calcium silicate and calcium aluminate. Although these materials induced several changes in the liver structure, they were not clinically relevant and represent a normal and reversible response of the liver to the presence of biocompatible materials in the body. Blood and immunohistochemistry analyses and local tissue reactions further confirmed that these materials possess good biocompatible potential.

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Introduction. The biggest drawback of composite materials is polymerization contraction and the existence of microcracks, therefore the market is now offering a wide variety of new composite materials. The aim of this study was to evaluate the marginal seal using dye method of class V cavities restored with self-etching flowable composite material Vertise Flow polymerized with different light-curing techniques. Material and Methods. The study was conducted on 60 extracted intact human teeth (30 premolars, 30 molars). Two cavities Class V (3?2?2 mm) were prepared in all teeth. Cavities on buccal surfaces were filled with self-etching flowable composite Vertise Flow (Kerr Dental Products), and on lingual with flowable composite Tetric Flow (Ivoclar Vivadent) using the corresponding adhesive systems. Polymerisation was performed using Bluephase Led flashlight C8 (Ivoclar Vivadent). Microleakage was tested using dye in a silver nitrate solution. Dye penetration was measured using stereo loupes with micrometer scale and six times magnification. Results. Linear dye penetration in intact molars restored using the classical polymerization technique and Vertise Flow composite was 3.41 ?m while with Tetric Flow it was 4.23 ?m. In intact molars restored using soft-start polymerization technique and Vertise Flow the dye penetration was 1.25 ?m while for Tetric Flow it was 4.23 ?m. Mean dye penetration in intact molars restored using pulse curing technique and material Vertise Flow was 1.02 ?m while for the composite Tetric Flow it was 4.35 ?m. In intact premolars restored using conventional curing technique and Vertise Flow dye penetration was 1.14 ?m while for Tetric Flow it was 3.90 ?m. Dye penetration in intact premolars restored using soft-start polymerization technique and Vertise Flow was 0.75 ?m while for Tetric Flow it was 3.15 ?m. Using a pulse polymerization technique and Vertise Flow in intact premolars dye penetration was 1.45 ?m while for Tetric Flow it was 3.76 ?m. Conclusion. Vertise Flow, self-etching flowable composite showed better marginal seal than flowable composite resin Tetric Flow. Smaller microcracks with Vertise Flow were confirmed after applying all three light-curing polymerization techniques.

Introduction/Objective The aim of this paper was to verify the biocompatibility of the newly synthesized nanostructured material based on calcium aluminate after implantation into the subcutaneous tissue of rats. Methods The study included 18 rats aged 10-11 weeks, divided into two experimental groups (n = 9). In all animals, incision took place on the back and two pockets of 15 mm in depth were made, in which sterile polyethylene tubes with test materials [calcium aluminate cement (ALBO-CA), calcium silicate cement with the addition of hydroxyapatite (ALBO-CSHA), and mineral trioxide aggregate (MTA) for the control group) were implanted. Six rats of each group were sacrificed in three observational periods (seven, 15, 30 days). Pathohistological analysis included inflammation, bleeding, fibrous capsule, and tissue integrity around the implanted material. Results After seven days of treatment, ALBO-CA and ALBO-CSHA showed better tissue response compared to MTA, with a statistically significant difference in inflammation intensity (p = 0.2781). The difference in vascular congestion and thickness of the fibrous capsule after implantation of ALBO-CA material compared to MTA was also statistically significant (p = 0.5567). At the end of the 30-day evaluation period, an identical inflammatory response of connective tissue at the site of implanting ALBO-CA, ALBO-CSHA, and MTA (score of 0.7) was recorded. The formation of thick or moderately thick fibrous capsule was found to be the thickest in ALBO-CA (grade 3.7). There were no statistically significant differences between the parameters analyzed after 30 days. Conclusion Newly synthesized ALBO-CA showed a satisfactory tissue response and confirmed biocompatibility after implantation in subcutaneous tissue of rats.

Background/Aim. Excessive consumption of acidic dietary substances, such as carbonated beverages, increased the chances of dental erosion. The aim of this study was to determine influence of carbonated beverages on enamel and dentin, during different intervals. Methods. Sixty samples were obtained from fifteen impacted third molars. Tooth crown was divided into four parts. One part was a control sample, immersed in destilled water and other three parts were the experimental samples, stored in the following tested beverages: carbonated water, Coca-Cola and Schweppes Bitter Lemon. For each beverage, pH was measured before immersion of the samples. The first group of twenty samples were analysed and photographed, using a Scanning Electron Microscope (SEM), after 60 minutes, the second group after 24 hours and the third group after 7 days of exposure to drinks. The enamel was analysed on the outer surface of the cusps and longitudinal section. Dentin was analysed on longitudinal section. An individually adopted scale was used for determination of the degree of erosive changes of these dental tissues. The data were analysed using the analysis of varance (ANOVA). Results. The pH levels of the tested beverages was bellow the critical pH for enamel demineralisation. The SEM images showed different intensity of erosive changes caused by the tested beverages. The analysis by ANOVA revealed a significant difference between all groups of the treated samples, after 60 minutes of exposure to beverages. The highest values of erosive changes showed the samples that were immersed in Schweppes Bitter Lemon. The analysis of the samples after 24 hours and 7 days showed that the samples immersed in Coca-Cola and Schweppes Bitter Lemon can be classified as one group that was statistically significantly different compared with the control samples and samples immersed in carbonated water. Conclusion. Prolonged exposure of dental tissue to carbonated beverages cause erosive changes and a loss of surface profile. Z, et al. Vojnosanit Pregl 2019; 76(4): 422-430. topljeni u Schweppes Bitter Lemon. Analiza uzoraka nakon 24 sata i sedam dana izloženosti delovanju napitaka pokazala je da uzorci potopljeni u Coca-Cola-u i Schweppes Bitter Lemon mogu biti svrstani u jednu grupu koja je statistički značajno različita u odnosu na kontrolne uzorke i uzorke potopljene u gaziranu vodu. Zaključak. Povećano izlaganje zubnih tkiva delovanju gaziranih napitaka uzrokuje erozivne promene i gubitak površinske strukture. Apstrakt Panić