Semiha Ekrikaya

Objective The purpose in the study was to evaluate the effect of biogenic silver nanoparticles (Ag NPs) synthesized by the green synthesis method on dentin bond strength in three different universal adhesives and investigate their antibiofilm activity against Streptococcus mutans (S. mutans). Materials and methods Three different universal adhesives (single bond universal, all-bond universal, and clearfil universal) were used in this study. Ag NPs were synthesized using rose hip (Rosa canina) extract as a reducing and stabilizing agent and they were characterized with STEM, UV–vis spectrophotometer, DLS, and zeta potential. Ag NPs were added to the adhesive resins at a rate of 0.05% (w/w), and their homogeneous distribution in the adhesive was determined using EDX spectrometry. Samples in all groups were tested at baseline-after 5000 and 10,000 thermal cycles. Adhesive composite discs were used for the live/dead analysis of S. mutans, MTT metabolic activity test, lactic acid production, and determination of colony-forming unit (CFU) values (n = 3). Ninety extracted caries-free human third molars were used to determine microtensile bond strength (μTBS) (n = 10). After the universal adhesive was applied to the dentin surface, composite resin (Z550 XT, 3 M ESPE, USA) was placed and sections were taken to form a composite-dentin stick of 1 mm × 1 mm wideness and 8-mm length. The sticks were broken at a rate of 1 mm/min under uniaxial tension in a universal testing machine, and the failure modes were determined by SEM. One-way analysis of variance (ANOVA) for antibacterial tests and two-way analysis of variance for μTBS tests were performed (p < 0.05). Results All universal adhesive groups containing Ag NPs showed higher antibacterial activity than control groups without Ag NPs (p < 0.05). There was a statistically significant difference in the live/dead assay analysis, MTT metabolic activity test, lactic acid production, and CFU values in the thermal cycled Ag NPs groups (p < 0.05). Antibacterial activity decreased in groups containing Ag NPs subjected to 10,000 thermal cycles. The highest lactic acid production 11.06 (± 0.629) and CFUs 7.61 (± 0.304), live bacteria 31.13 (± 0.466), and S. mutans MTT metabolic activity 0.29 (± 0.376) at AU (All-Bond Universal—Ag NPs) 10,000 thermal cycles group. There was no difference in μTBS values between the initial and 5000 thermal cycle groups, there was a difference between the 10,000 thermal cycle groups. The CU (Clearfil Universal—Ag NPs) group subjected to 10,000 thermal cycles showed lower μTBS 11.1 (± 3.2). Conclusion In conclusion, universal adhesives containing biogenic Ag NPs showed higher antibacterial activity than the control groups and did not reduce the μTBS. Clinical relevance Antibacterial universal adhesives can contribute to restoration success in clinical applications by reducing residual bacteria and preventing secondary caries formation.

Our study aimed to evaluate the antibacterial activities and dentin bond strengths of silver nanoparticles (Ag NPs) and silver nano-graphene oxide nanocomposites (Ag@nGO NCs) produced by green and chemical synthesis methods added to the dental adhesive. Ag NPs were produced by green synthesis (biogenic) (B-Ag NPs) and chemical synthesis methods (C–Ag NPs) and deposited on nGO (nano-graphene oxide). Ag NPs and Ag@nGO NCs (0.05% w/w) were added to the primer and bond (Clearfil SE Bond). Group 1: control, Group 2: nGO, Group 3: B-Ag NPs, Group 4: B-Ag@nGO NCs, Group 5: C–Ag NPs, Group 6: C–Ag@nGO NCs. Streptococcus mutans (S. mutans) live/dead assay analysis, MTT metabolic activity test, agar disc diffusion test, lactic acid production, and colony forming units (CFUs) tests were performed. Bond strength values were determined by the microtensile bond strength test (μTBS). Failure types were determined by evaluating with SEM. Statistical analysis was performed using one-way ANOVA and two-way ANOVA (p < 0.05). There was a difference between the groups in the viable bacteria ratio and lactic acid production tests (p < 0.05). When the inhibition zone and S. mutans CFUs were evaluated, there was no difference between Group 3 and Group 4 (p > 0.05), but there was a difference between the other groups (p < 0.05). When the metabolic activity of S. mutans was evaluated, there was a difference between Group 1 and other groups, and between Group 2 and Group 5, and Group 6 (p < 0.05). There was no difference between the groups in the μTBS values (p > 0.05). As a result, although the antibacterial activity of B-Ag NPs and B-Ag@nGO Ag NPs obtained by green synthesis is lower than that of chemically synthesis obtained C–Ag NPs and C–Ag@nGO NCs, they provided higher antibacterial activity compared to the control group and did not reduce μTBS. The addition of biogenic Ag NPs to the adhesive system increased the antibacterial effect by maintaining the bond strength of the adhesive. Antibacterial adhesives can increase the restoration life by protecting the tooth-adhesive interface.

Amaç: Bruksizm ile ilgili bilgi kaynağı olarak YouTube™ videolarının içeriğinin ve kalitelerinin değerlendirilmesidir. Gereç ve Yöntem: YouTube™ videolarında “diş sıkma, bruksizm” kelimeleri ile Türkçe videolarda arama yapıldı ve ilk sırada yer alan videoların URL’leri kaydedilerek iki araştırmacı tarafından tüm videolar incelendi. Videolara ait tanımlayıcı istatistikler kaydedildi ve verilerin minimum, maksimum, ortalama, standart sapması hesaplandı. Elde edilen değerler, istatistiksel olarak incelendi ve sürekli değişkenler Kruskal-Wallis testi ile analiz edildi (p<0.05). Bulgular: Toplam 250 video değerlendirmeye alındı. Bu videolardan değerlendirme kriterlerine uyan 68 video çalışmaya dahil edildi. Değerlendirmeyi yapan iki gözlemci arasında istatistiksel olarak anlamlı seviyede yeterli uyum vardı (Kappa=0.754, p0.05). Sonuç: Bruksizm ile ilgili YouTube™’da yer alan videoların çoğu az yararlıdır. Alanında uzman hekimler ve akademisyenler, YouTube™’a daha yararlı ve bilgilendirici videolar ile katkı sağlayabilirler, bireylerin doğru bilgiye ulaşmasına ve toplum sağlığına faydalı olabilirler.

Aim The purpose of our study was to evaluate the antibacterial activities and dentin bond strengths of silver nanoparticles (Ag NPs) and silver nano-graphene oxide nanocomposites (Ag@nGO NCs) produced by green and chemical synthesis method added to dental adhesive. Methods Ag NPs were produced by green synthesis (B-Ag NPs) and chemical synthesis methods (C-Ag NPs) and deposited on nGO (nano-graphene oxide). Ag NPs and Ag@nGO NCs (0.05% w/w) were added to primer and bond (Clearfil SE Bond). Group 1: control, Group 2: nGO, Group 3: B-Ag NPs, Group 4: B-Ag@nGO NCs, Group 5: C-Ag NPs, Group 6: C-Ag@nGO NCs. S. Mutans live/dead assay analysis, MTT metabolic activity test, agar disc diffusion test, lactic acid production and colony forming units (CFUs) tests were performed. Bond strength values were determined by microtensile test. Failure types were determined by evaluating with SEM. Statistical analysis was performed using one-way ANOVA and two-way ANOVA (p < 0.05). Results There was a difference between the groups in the viable bacteria ratio and lactic acid production tests (p < 0.05). When the inhibition zone and S. Mutans CFUs were evaluated, there was no difference between Group 3 and Group 4 (p > 0.05), but there was a difference between the other groups (p < 0.05). When metabolic activity of S. Mutans was evaluated, there was a difference between Group 1 and other groups, and between Group 2 and Group 5 and Group 6 (p < 0.05). There was no difference between the groups in the microtensile bond strength values (p > 0.05). Conclusion Adhesives containing B-Ag NPs and B-Ag@nGO NCs provided sufficient antibacterial activity and did not reduce bond strength values. Clinical Significance: The addition of biocompatible B-Ag NPs and B-Ag@nGO NCs to the adhesive system increased the antibacterial effect by maintaining the bond strength of the adhesive. Antibacterial adhesives can increase the restoration life by protecting the tooth-adhesive interface.

Objective The purpose of this study was to examine the effect of applying two different prophylaxis pastes with various protocols on the degree of bleaching and color stability in the office bleaching process with a bleaching agent containing 40% hydrogen peroxide. Material and method The 300 teeth of 15 (9 female, 6 male) patients were included in our study, and 5 different study groups were randomly formed. The bleaching process with Ultradent Opalescence Boost (Ultradent, South Jordan, USA) was performed according to the manufacturer’s instructions. Two different prophylaxis pastes, Ultrapro (Ultradent, Cologne, Germany) and Cleanic (Kerr, Rastatt, Germany), were applied with protocols determined according to the groups. The effect on color stability at 6-, 12-, and 24-month follow-up was determined using the CIE L* a* b* color system. The changes in the parameters were analyzed using the one-way ANOVA, chi-square, and Tukey test (p > 0.05). Results The evaluation rate of the treatments was 100% at the end of 24 months. Control group 6-month ΔE (0–6) and 12-month ΔE (0–12) values were higher than 24-month ΔE (0–12) values. UU + UU, KC + KC, and UU group 6-month ΔE (0–6) values were higher than 12-month ΔE (0–12) values. In addition, 6-month ΔE (0–6) and 12-month ΔE (0–12) values were higher than 24-month ΔE (0–24) values. KC group 6-month ΔE (0–6) and 12-month ΔE (0–12) values were higher than 24-month ΔE (0–24) values. Control, UU + UU, KC + KC, UU, and KC group ΔE (1–6) values at 6 months were lower than 12-month ΔE (1–12) and 24-month ΔE (1–12) values in all groups. In addition, 12-month ΔE (1–12) values were lower than 24-month ΔE (1–24) values. According to the study data, there was no statistically significant difference between the groups according to the prophylaxis paste and prophylaxis procedure (p > 0.05). However, it was observed that whiteness decreased in all groups over time. Conclusions Discoloration was observed at 6 months, 12 months, and 24 months after bleaching. However, at the end of 24 months, the tooth color was significantly whiter than the initial color. Clinical relevance Pre-bleaching prophylaxis application and pre-bleaching and post-bleaching prophylaxis application have no effect on color stability.