Objective: The aim of this study was to evaluate the effects of 2 home bleaching agents [16% carbamide peroxide (CP) and 6% hydrogen peroxide (HP)] on the color change and surface roughness of discolored anterior and posterior resin composites. Material and Methods: Estelite Sigma Quick (ES) and Estelite Posterior (EP) resin composites were used in the present study. A total of 60 samples were prepared (thirty samples from each resin composite). Samples were immersed into the coffee solution throughout the 12 days. Samples were randomly divided into 3 groups, to applying 2 different bleaching agents and a control group (n=10). Bleaching agents were applied for 14 consecutive days. The color changes of the samples were measured at 3 different times, baseline (T0), after discoloration (T1) and bleaching procedures (T2). Surface roughness changes were measured at T1 and T2. Color differences were calculated using the CIEDE 2000 (ΔE00) formula. Differences were analyzed using one way, two-way analysis of variance and Tukey multiple comparison tests. Results: ΔE00 values showed significant differences after coffee immersion and bleaching applications in both resin composites (p<0.05). Immersion in coffee caused more color change in EP samples (ΔE00=12.46±0.47). Bleaching agent was a significant factor for the color recovery in ES samples (p<0.05). CP application in ES groups and HP application in EP groups increased the surface roughness (p<0.05). Conclusion: Bleaching agents used in the present study showed color recovery effect on discolored resin composites. The potential effect of bleaching agents on surface roughness and the sensitivity of the posterior resin composites to discoloration should be considered in restorative treatment.
ÖZET Amaç: Bu çalışmanın amacı dört farklı geleneksel Türk içeceğinde bekletilen geçici restorasyon materyallerinin renk değişimlerinin karşılaştırılmasıdır
(1) Background: This study aimed to examine the effect of bleaching agents on the release of triethylenae glycol dimethacrylate, 2-hydroxyethyl methacrylate, bisphenol A, urethane dimethacrylate, and bisphenol A-glycidyl methacrylate monomers, which are released from different composite resins, using the high-performance liquid chromatography (HPLC) method. (2) Methods: Ninety disc-shaped specimens were produced and immersed in artificial saliva. After different bleaching applications [office type bleaching (OB) and home type bleaching (HB)], the specimens were immersed in a 75 wt% ethanol/water solution, and the released monomers were analyzed by HPLC at predefined time intervals: 1, 7, and 28 days. The Kruskal–Wallis and Mann–Whitney U tests were conducted for statistical analysis (p = 0.05). (3) Results: The monomers were released at all times from all composite specimens. The monomer release was increased over time. The highest monomer release was detected on day 28. Bleaching applications affected monomer release. No statistical difference was found between OB and HB applications (p > 0.05). The most released monomer was Bisphenol-A in all composites. (4) Conclusion: Given that a residual monomer release from composite resins has a toxic effect and that bleaching treatments increase this release, a treatment protocol should be made in accordance with the manufacturer’s instructions.
Aim: The aim of this study is to investigate the effects of green tea and rosehip tea, on the color stability of nanohybrid and bulk-fill composite resins. Methodology: A total of 60 disc-shaped samples were made from two types of A2 resin with nanohybrid (Tetric N Ceram, Ivoclar Vivadent, Schaan, Liechtenstein) and bulk-fill (Filtek Bulk-Fill, 3M ESPE, MN, USA) structure with the help of 10 mm diameter and 2 mm thick Teflon molds in this study. All samples were finished and polished with 4-stage (thick, medium, fine, superfine) polishing discs (Sof-lex, 3M ESPE, MN, USA) and kept in an oven at 37 °C for 24 hours. The samples, whose initial color measurements were made by spectrophotometer, were divided into subgroups for the control group and two different herbal teas (Green tea, Rosehip) (n=10). Color measurements were repeated, and ΔE values were calculated. Wilcoxon, Kruskal-Wallis, and Bonferroni tests were used to analyze the data (p < 0.05). Results: There was no statistically significant difference in color change between the composite resins (p > 0.05). No significant color change was found for either the Tetric N-Ceram or Filtek Bulk-Fill composite resin samples immersed in distilled water (p > 0.05, ΔE<3.3). Conclusion: Rosehip and green tea affect the color stability of composite resin restorations. Whereas the color change caused by green tea is at a clinically acceptable level, that stemming from rosehip tea falls within clinically unacceptable levels. How to cite this article: Tunçdemir MT, Dereli Z, Bahar A. The effect of different herbal teas on the color stability of nanohybrid and bulk-fill composites. Int Dent Res 2022;12(Suppl.1):103-7. https://doi.org/10.5577/intdentres.445 Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.
Abstract The aim of this study was to evaluate the antibacterial effect of conventional glass ionomer cement with the addition of antibacterial constituents in its liquid preparation. Two groups of glass ionomers prepared with propolis and chlorhexidine and a third group without any additive used as control were sterilized by low-temperature hydrogen peroxide plasma sterilizer at the sterilization unit. Seven to eight disk-shaped restorative materials of each group were placed on the Mueller Hinton Agar with sheep blood 5% v/v, on which Streptococcus mutans inoculated. The plates were incubated at 37°C in 5% CO2 for 24 to 48 hours. After 24-hour and 48-hour-incubation, inhibition zone diameters of each restorative materials were measured. No distinct inhibition zone was reported; only a slight zone (6 mm) around the contact surfaces of each material was observed after the 24-hour and 48-hour incubations. No significant difference was observed in the inhibition zone diameters between the two test groups and control. Within the limitations of this study, results revealed that there was no antibacterial difference among glass ionomers prepared with propolis and chlorhexidine.
Aim nbsp The aim of this study was to evaluate the rate of bruxism among the students attending Necmettin Erbakan University Faculty of Dentistry according to class by using a questionnaire and possible causes of this distribution Material and Method nbsp A total of students aged between and were included to the study Before the study the individuals were informed about the survey and they were allowed to fill the questtionnaires in private SPSS software and chi square test was used for statistical analyses Results nbsp Bruxism rate was found as Among the classes the rates were and in first second third fourth and fifth grades respectively In females the bruxism rate was and in males It was found that there was no significant difference among the classes P gt in bruxism rates and distribution of both sexes P gt Bruxism was higher in females than males except for the first grade Conclusion nbsp The bruxism rate that was higher in first grade was decreasing towards fourth grade but it was starting to increase again in fifth grade Besides the bruxism rate was higher in females than males except for the first class These results suggest that bruxism is closely related with stress
Aim: Secondary caries is an important problem in dental composite restoration, and nanoparticles are commonly added to the structures of resin composites to improve their antimicrobial properties. The aim of this study is to evaluate the mechanical properties of composite materials containing bioactive glass (BAG) and an experimental nano zinc-silica (NZS) complex.
Methodology: An experimental resin composite containing 70 wt% filler was produced and used as a control sample. This experimental resin composite was then modified by adding different amounts of BAG (10%), NZS (10%), and both BAG and NZS (10% + 10%). NZS was synthesized in situ by milling zinc and silica to nanoscale level. Compressive strength and flexural strength were investigated using a universal testing machine. Data were analyzed using one-way ANOVA and the Tukey post-hoc test.
Results: There were no statistically significant differences in compressive strength caused by the filler amount, but statistically significant changes were found in flexural strength. Although the addition of antimicrobial agents to resin composites reduces their physical properties, this is not a clinically unacceptable limit.
Conclusion: NZS exhibits better mechanical properties than does BAG, but both materials can be used safely in restorative materials.
How to cite this article: Tunçdemir MT, Demirel MG. Mechanical properties of resin composites containing bioactive glass and experimental nano zinc-silica complex. Int Dent Res 2021;11(Suppl.1):137-42. https://doi.org/10.5577/intdentres.2021.vol11.suppl1.21
Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.
