The placement of appropriate root-end filling materials in contact with periradicular tissues, with improved adaptation and biological properties is critical for the long-term success of the periapical surgery. The purpose of the present study was to evaluate and compare the bio-properties of four different root canal filling materials with respect to storage media. Two mineral trioxide aggregates: MTA-Angelus (Angelus, Londrina, PR, Brazil) and ProRoot MTA (Dentsply Maillefer, Ballaigues, Switzerland) and two glass ionomer cements: one conventional Ketac Molar (3M ESPE AG, Seefeld, Germany) and a resin reinforced core build-up glass ionomer Vitremer (3M ESPE AG, Seefeld, Germany) were evaluated. Eighty healthy single-rooted human extracted teeth without curvature and with closed apices were included in this experiment. The canals were instrumented with K-files up to size #35. Adequate irrigation was performed during preparation and instrumentation using 2.6% NaOCl. Root canals were obturated with vertically condensed gutta-percha and roots end were apically resected 3mm. The samples were randomly divided in four groups (n=20) and each group was assigned to one of the four tested materials. Three-mm depth preparations were made at root ends using cylindrical diamond burs and constant water spray, and were filled with the tested materials. The roots were then wrapped in wet gauze and placed in an incubator at 37°C for 48 hours to allow complete set of the root-end filling materials. Each group was divided in two subgroups (n=10) and stored in polypropylene sealed containers for 60 days at 37°C. Specimens of the first subgroup were immersed in 5ml of a physiological-like buffered Ca- and Mg-free solution (PBS, pH=7.4) and those of the second subgroup were in 5ml of deionized water (DW, pH 6.8) After 10 minutes of immersion and at the established endpoint times, the specimens were analyzed by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). Statistical analysis was performed by t-test and one-way ANOVA (p<0.05). The morphology of cement–dentin interface in fresh restorations soaked 10 min in PBS showed the margins of all cements free from porosities or gaps. EDX elemental analyzes on MTA and ProRoot MTA revealed calcium, silica and phosphorous peaks, while on Ketac Molar and Vitremer, aluminum, silica, zinc and fluoride peaks were detected. After 60 days of immersion in PBS calcium-phosphate deposits completely covered the surface, the margin and partially also the peripheral dentin surface of MTA and Pro Root MTA. Glass ionomer cements showed the presence of thick irregular deposits (p<0.05). In deionized water, EDX analyses revealed no deposits forming after 60 days. SEM analysis showed the margins of MTA and ProRoot MTA with significant discontinuities compared with glass ionomer cements (p<0.05). Mineral trioxide aggregate cements are significantly more bioactive compared to conventional or reinforced glass ionomers upon aging in PBS. Glass ionomer cements provide more optimal adaptation to dentinal cavity walls of all cements than MTA cements when used as retrograde fillings.

Objective: The aim of this in vitro study was to evaluate the influence of erosive conditions on the wear resistance of aesthetic direct restorative materials. Methods: Six dental filling materials were tested: two composites (Filtek Z550 and X-tra fil), two compomers (Dyract Extra and Twinky Star) and two glass ionomers (Ketac Molar and Fuji II LC). Twenty disks (10mm×2mm) of each material were prepared (n=120) and kept in artificial saliva at 37˚C for 24 hours. Specimens were cycled in acidic soft drink (Coca-Cola) 5×/day, for 5', over 30 days. Initial surface roughness ISR (Ra-μm) and final surface roughness FSR were measured using a profilometer. The wear rate was calculated as difference of final minus the initial roughness (ΔSR=FSR-ISR). For statistical analysis t-test and one-way ANOVA test were used by GraphPad Prism version 5.03 statistical software. The level of significance was set at p<0.05. Results: The erosive wear rates (mean±SD, µm) after exposure to acidic beverage were: 0.30±0.03 (Ketac Molar), 0.28±0.04 (Fuji II LC), 0.27±0.00 (Filtek Z550), 0.23±0.01 (X-tra fil), 0.20±0.00 (Twinky Star) and 0.14±0.01 Dyract Extra, respectively. There were significant differences between the tested materials (p<0.05). Conclusions: Dental filling materials had different behaviour under the same erosive condition, however all investigated aesthetic restorative materials showed surface degradation. These findings suggest that erosive wear resistance of tooth coloured restoratives could influence their longevity in intraoral acidic conditions. Acknowledgements: The study was supported by the Internal Research Grant no. 5/30.01.

Introduction: It is a well-known fact that during a dental impression, some patients suffer from the gag reflexes. Aim of the study: Even if the main tendency is to use medication, our goal is to find a way to combat it.Material and methods: With the help of our 155 volunteering students, from UMFST Târgu Mureș, who agreed on having their dental impression taken, using alginate material, we tried to combat the gag reflex, using the following techniques: the high-leg method, salt crystals, as well as using a special impression tray.Results: When we applied all of these methods, great attention was payed, as we diligently wrote everything down. After all the work was done, we obtained the following results: 130 did not show any vomiting signs, 17 of them presented moderate vomiting reflex and only 8 of them have shown extreme vomiting reflex, leading to the point where the impression could not be performed.Conclusions: On the one hand, for the less informed people, these techniques present a better outcome; on the other hand, however, we wish to highlight one thing: the skills of the doctor are of utmost importance.

Introduction: Aesthetic materials for direct restorations can suffer changes in the oral cavity due to multiple factors acting at this level. The aim of the study was to demonstrate that aesthetic materials undergo structural changes in texture and chemicals, depending on the nature of the extrinsic factor, concentration, and exposure time. Material and methods: We used 3 types of composites, a self-polymerizing composite, two photo-polymerizing composites, and a glass ionomer. 210 teeth were initially immersed in artificial saliva as a control solution and afterwards immersed into artificial gastric juice, ethyl alcohol, energy drink, and distilled water. With the help of a pH meter, we determined the pH of the substances both before and after immersing the teeth in solutions. The teeth were monitored for 24-48 hours in a thermostat bath at 37 degrees Celsius, after which they were analyzed with the help of a rough meter that measures the smallest surface changes. Results: Significant changes in pH occurred in alcohol, where a considerable decrease was observed after 48h. Also, the alcohol produced the most aggressive changes of texture in the composites, and the smallest changes occured in the composite with nanofiller. The glass ionomer was the most affected of all the materials due to the exposure to both alcohol and artificial gastric juice, respectively energy drinks so that the surface analysis could not be performed. Conclusions: The results of the in vitro study are clinically important because the glass ionomer is much too rotten in these extreme situations. Thus, its use is not recommended both in patients with gastroesophageal reflux as well as in alcoholics and persons consuming energy drinks.

Changes in the surface roughness of dental restorative materials after tooth brushing are inevitable. The abrasion is known to increase the possibility of dental plaque accumulation which is responsible for several pathologies of the oral cavity. The aim of this in vitro study was to evaluate the changes of surface roughness of microhybrid composite materials produced by different toothbrushes with and without toothpaste. Forty-eight specimens of two composite materials (Charisma and Super-Cor) were prepared using a silicone template according to the manufacturer�s instructions. Each sample was brushed for eight hours. Each group of specimens was divided in two subgroups: half of the samples were brushed using only distilled water and the other half with a mixture of distilled water and toothpaste (Colgate Total; ratio 1:1). The average roughness value (Ra) of surfaces were measured with profilometer three times: the initial measurement was performed before starting the toothbrush simulation, the second was after 4 hours and the third was after 8 hours of brushing. Three different bristle stiffness toothbrush heads were used (medium sensitive, medium and soft). After collecting all numerical data one-way ANOVA and Friedman tests were performed for statistical analysis. All examined microhybrid composites exhibited changes in surface roughness after the toothbrush simulation. The simulation of toothbrushing without toothpaste, only with water as cleaning substrate, showed at every measurement the lowest values of roughness in all three toothbrush heads. Significantly increase of mean Ra values were observed in both tested composite samples when medium and soft toothbrushes with toothpaste were used. The surface roughness changes of tested microhybrid composites depend on the brushing procedure. The toothpaste has a much greater effect on the abrasion than the type of toothbrush.