Esra Cengiz-Yanardag

Aim: This study was to evaluate the color stability and surface roughness of conventional resin composites after immersion with two different energy drinks.Materials and Methods: 66 disc specimens (6 x 2 mm) were prepared from micro-hybrid (G-ænial Posterior) and nano-hybrid (Clearfil Majesty Esthetic) resin composites. Post-polymerization was conducted by storing all specimens in distilled water at 37 °C for 24 hours. Baseline color and surface roughness (Ra) measurements were performed, after which the specimens were randomly divided into three groups (n=11/subgroup) according to the immersion solution used: Group 1 (distilled water), Group 2 (Red Bull), and Group 3 (Burn). After 7 days of immersion, final measurements were recorded. Color variations (ΔE00) were determined using a spectrophotometer and the CIEDE2000 formula before and after the immersion. Data were subjected to ANOVA analysis (α = 0.05).Results: There were no statistically significant differences in color stability between the nanohybrid and micro-hybrid resin composites (p > 0.05). Both resin composites exhibited color changes exceeding the AT threshold (> 1.8) and the PT threshold (> 0.8). The highest ΔE00 values were found in the specimens exposed to Red Bull. Specimens in distilled water showed ΔE00 values below the AT threshold (< 1.8). In terms of Ra values, significant differences were noted between the materials in both the Ra0 and Ra1 measurement intervals (p < 0.001 and p =0.002). The Clearfil Majesty Esthetic specimens had the highest surface roughness, with Red Bull resulting in the greatest Ra values.Conclusion: Over the 1-week immersion period, all tested solutions led to increased color changes and surface roughness in the restorative materials.

This study aimed to compare the marginal and internal adaptation of two bulk-fill and one conventional composite resin placed with different techniques using micro-CT. Twenty-one extracted human third molars with standardized mesio-occlusal cavities (a bucco-lingual width of 3 mm, a mesio-distal width of 5 mm, and a depth of 4 mm) were randomly divided into three groups (n = 7): Group 1 was restored with SonicFill 2 using sonic activation and 4 mm single layer, Group 2 with Tetric N-Ceram Bulk Fill in a 4 mm single layer and Group 3 with Clearfil Majesty Posterior using a 2 mm incremental technique. All restorations underwent 5,000 thermal cycles before micro-CT scanning. Data were analyzed using Kruskal-Wallis and Mann-Whitney U tests (p < 0.05). The SonicFill 2 group showed a significantly greater marginal gap volume than the Tetric N-Ceram Bulk Fill group (p = 0.023), while no significant differences were found among the Clearfil Majesty Posterior group and the others (p > 0.05). No significant differences were observed among the groups in terms of internal void volume (p = 0.101). These findings suggest that variations in marginal adaptation among different composite resins may be attributed to differences in their material composition and placement techniques which have a limited effect on internal adaptation.

Objectives: This study aimed to assess the publication rates of abstracts presented at the ConsEuro Congress using a web-scraping method and to analyze factors correlated with these publication rates.Methods: Abstracts presented at eight ConsEuro meetings held between 2003 and 2019 were evaluated for subspecialty, study design, number of authors, and the country of the principal investigator’s institution. For abstracts confirmed as subsequently published using a web-scraping method, the following data were recorded: time to publication, the journal of publication, impact factor, quartile, index status, Scientific Journal Ranking of the journal at the year of publication, and changes in the number of authors after publication.Results: Out of 1,426 abstracts presented, 478 were published in peer-reviewed journals, yielding a publication rate of 33.5%. The median time to publication was 12 months. The leading journal in terms of publication rate was Clinical Oral Investigations. There was no statistically significant difference in publication rates across years. Abstracts related to laser therapy, caries, and dental materials had significantly higher publication rates compared to other subspecialties. Animal, basic, and clinical research studies were more likely to be published. Both study design and subspecialty influenced publication rates, which decreased over time.Conclusions: A considerable amount of scientific data and preliminary results presented at conferences, which could contribute to scientific knowledge, are overlooked due to low publication rates. The findings of this study may encourage ConsEuro participants to submit well-planned and rigorous studies that are more likely to complete the full publication process.

The aim is to investigate the effect of resveratrol on micro-shear bond strength (µSBS) of adhesive to enamel after 40% hydrogen peroxide application. For µSBS test, 50 teeth were obtained, 2/3 of crowns were embedded into acrylic resin. After application of hydrogen peroxide twice, teeth were randomly allocated to control group and 9 groups (n = 15) according to concentrations (0.5, 1, 2 µM) and application periods (10, 30, 60 min) of resveratrol. Following, composite resin was placed onto enamel surfaces using 3 tygon tubes for each tooth. µSBS test was performed and failure modes were displayed. To analyze µSBS values, Kruskal Wallis and Mann-Whitney U tests were performed. µSBS values of 1 µM resveratrol for 10 min applied group were statistically higher than control group (p < 0.05). 1 µM resveratrol showed higher µSBS values than 0.5 µM and 2 µM (p < 0.05). No significant difference was detected between application periods (p > 0.05). The improvement of µSBS values with 1 µM resveratrol application may be promising for clinical problems related to reduced bond strength after bleaching.

Objective: The objective of this study was to assess the impact of various finishing and polishing systems on the color stability of composite resins treated with coffee. Methods: Fifty samples of each of nanohybrid and supra-nanohybrid composite resin materials were prepared and each material was randomly divided into 5 groups (n=10): Group 1: Control group (mylar strip), Group 2: One Gloss (one step), Group 3: One Gloss + polishing paste, Group 4: Soflex disk (multistep), Group 5: Soflex disk + polishing paste. The samples were colored in coffee solution for 144 hours to simulate six months of coffee consumption after polishing. The color of the samples before-after staining was measured with a spectrophotometer and ∆E00 values were calculated. Results: Material, polishing type and the interaction of these two parameters had a statistical effect on the color change values (p< 0,001). The ∆E00 values of supra-nanohybrid composite resin were higher than nanohybrid. Both materials exhibited color change above the thresholds of clinical perceptibility (PT> 0,8) and acceptability (AT> 1,8). In terms of polishing types, the highest ∆E00 was found in the control group and the lowest in the disk group. The additionally applied polishing paste caused a non-significant decrease in the color change of the single-step polishing system (p< 0,05) and a statistically significant increase in the multi-steps polishing system (p> 0,05). Conclusion: Considering the limitations of the study, it can be concluded that the use of multi-steps discs is more advantageous in preventing discoloration of composite resins.

The aim is to assess viability of fibroblasts exposed to 2 CAD–CAM blocks and a nanohybrid resin after application of hydrogen peroxide (HP) and resveratrol with 2 extraction media at 24 h, 48 h, and 72 h. Eighteen specimens were obtained from Lava Ultimate (LU), Vita Enamic (VE), and Grandio (GR). Specimens of each material were divided into 3 groups (material only, bleached, resveratrol applied) for 2 extraction media as artificial saliva (AS) and phosphate buffer saline (PBS) (n = 3). For bleached group, 40% HP was applied to specimens for 20 min twice. For resveratrol group, 0.5 µM resveratrol was applied after bleaching for 10 min. Mouse fibroblast cells were exposed to extracts of each group. The viability of cells was determined with MTT assay at 24 h, 48 h, and 72 h. Cell viability data (%) were analyzed statistically using one-way ANOVA, and post hoc Tukey test. Bleached materials showed the lowest cell viability (PBS; p < 0.01/ AS; p < 0.001). There is no statistically significant difference between resveratrol applied and bleached groups (PBS; p = 0.14/ AS; p = 0.072). Regardless of period of time and procedure, GR showed lower viable cell numbers than LU and VE (p < 0.001). Viable cell numbers were higher at 24 h than at 72 h (p < 0.001). There was no statistically difference between AS and PBS (p > 0.05). For all materials, the application of resveratrol did not affect the cell viability which decreased after bleaching over time. The decrease in nanohybrid resin was more critical than hybrid CAD–CAM blocks. The type of extraction media had no effect on cell viability results.

The aim of this study was to evaluate the effects of various whitening agents on the surface roughness and optical characteristics of different types of resin composite restorations. Fifty specimens were prepared for each resin [G‐ænial Posterior (GP), SonicFill‐2 (SF), Solidex (SDX), and Nova Compo HF (NC)]. Following baseline color and surface roughness (Ra) measurements, the specimens were randomly divided into 5 groups (n = 10/group) according to whitening concepts: control (distilled water), in‐office bleaching [OB‐(Opalescence Boost)], at‐home bleaching [HB‐(Opalescence PF)], whitening toothpaste [WT‐(Signal White Now)], and whitening mouthwash [WM‐(Listerine Advanced White)]. ∆E₀₀, ∆TP₀₀, and ∆WI_D values were calculated before and after the whitening procedure with a spectrophotometer using the CIEDE2000 formula. Surface roughness measurements were repeated. The surface topography was determined using atomic force microscopy. Two‐ and three‐way analyses of variance and Tukey's post‐hoc test were performed, with p < 0.05 regarded as indicative of significance. No significant differences were detected among the resin composite materials in terms of the ΔE₀₀ values (p > 0.05). Color change of all resin materials was above the AT threshold (>1.8) and the PT threshold (>0.8). All restorative materials presented acceptable (AT00 values. Solidex specimens demonstrated the lowest W_ID values compared to the other composites. There were significant differences among the whitening procedures with respect to ΔE₀₀, ΔTP₀₀, and W_ID values (p < 0.001). SF/WT combination showed the highest and clinically unacceptable ΔE₀₀ values. The highest roughness values were observed in the SDX specimens and the combination of SDX/OB. The effect of whitening agents on the optical characteristics and surface roughness of restorative materials depends on the type of material, agent, and time.Research Highlights: Clinicians should be aware that long‐term use of over‐the‐counter products due to the abrasive effects of their ingredients and repeated bleaching session applications may affect the color stability and surface roughness of resin composites.

Yeni ilaçların, tıbbi cihazların ve diğer tedavi yöntemlerinin insanlara yararlı olabilmesi için yaygın olarak kullanılmaya başlanmadan önce güvenlilikleri ve etkililiklerinin gösterilmesi gereklidir. Bu amaçla yapılan klinik araştırmalar bilimsel bilgi elde etmek amacıyla gönüllü insanların katılımıyla gerçekleştirilen çalışmalardır. Klinik çalışmaların tasarımını etik ilkelere uygun olarak yapmak, katılan gönüllü deneklerin güvenliğini sağlamak, çalışmanın yapılabilmesi için ilgili merkezlerden onay almak, sonuçlarının geçerliliğini yorumlamak ve belirlemek için iyi bir çalışma bilgisi ve mevcut mevzuatlara hâkimiyet gereklidir. Ülkemizde bu amaçla birçok düzenleme ve mevzuat bulunmakta ve araştırmacıların bu mevzuatlara uyması ve bu alanlarda eğitimli olması beklenmektedir. Bu çalışmanın amacı, Türkiye’deki klinik araştırma sürecini mevcut durumu göz önünde bulundurarak değerlendirmektir. Ülkemizin nüfusu ve sağlık hizmetlerindeki potansiyeli göz önüne alındığında beklenen düzeyde olmayan klinik araştırma sayısının doğru ve etkili stratejiler ve eylem planlarıyla önümüzdeki yıllarda önemli ölçüde artması beklenmektedir.

Objectives: To determine the influence of dental students' dietary habits on tooth color. Materials and Methods: The ethical committee of Mersin University granted permission to conduct the study (number 2022/708). The consent form was approved by all participants. The following exclusion criteria were used for the selection of participants: gingival problems, the presence of excessive abrasion, dental malocclusion, a history of orthodontic or bleaching treatment, caries, and composite fillings on the facial surfaces of the teeth. A questionnaire consisting of 18 questions was directed to 202 students included in the study. The color of the upper central incisors and canines of the participants who completed the questionnaire was measured using a clinical spectrophotometer device(Vita Easyshade V). Tooth color assessment was performed by a calibrated operator. The L*, C*, H*, a*, and b* parameters were recorded. Data were subjected to descriptive statistical analysis, Spearman's rho correlation analysis and multivariate testing. Results: The sample consisted of 202 dentistry students. 96.5% of the participants were between the ages of 18-25 and more than half were female. L*, C*, H*, a*, and b* mean values in canine and incisor teeth did not differ statistically significantly according to age groups(p>0.05). The mean values of C* and b* in canine teeth and the mean values of all parameters except L* in incisor teeth showed significant differences according to gender(p<0.05). Staining beverages in the diet had no effect on L*, C*, H*, a*, and b* parameters of the canine and incisor teeth. A negative correlation was found between the frequency of consuming energy drinks and the L* value in the incisor teeth(r=-0.215; p=0.016). Conclusion: Females have lighter teeth than males. The increase in the amount of consumption of the evaluated staining beverages is one of the factors that cause the tooth colors to become darker and mat.