The purpose of this study was to investigate the effect of final surface treatment and dental composite type on the roughness of the composite surface, composite/enamel interface, and composite/cementum interface, as well as on the polishing time. Class V cavities prepared in extracted teeth (n = 126) were restored using one of the three nanohybrid composites with different filler sizes. The specimens were randomly assigned to three different finishing and polishing sequences. The roughness (Ra) of the investigated surfaces was measured using the contact profilometer. The time required to achieve visible gloss was documented. The data were analyzed using ANOVA with Tukey’s post hoc test (p < 0.05). There was no significant influence of the composite type on the restoration surface roughness (p = 0.088), while the polishing method had a significant impact (p < 0.001). The Ra of the composites ranged between 0.08 µm and 0.29 µm, with the lowest values (0.09 µm ± 0.05 µm) found in the aluminum oxide disc group (p < 0.001). The time to achieve a visible composite gloss was influenced by the polishing method, composite type, and interactions between these factors (p < 0.001). The interface roughness was significantly greater than that of the composite surface (p < 0.001), and depended on the composite type and polishing system employed.

We aimed to assess the effect of oral probiotics containing the Streptococcus salivarius K12 strain on the salivary level of secretory immunoglobulin A, salivation rate, and oral biofilm. Thirty-one consenting patients meeting the inclusion criteria were recruited in this double-blind, placebo-controlled, two-arm, parallel-group study and randomly divided into probiotic (n = 15) and placebo (n = 16) groups. Unstimulated salivation rate, concentration of salivary secretory immunoglobulin A, Turesky index, and Papillary-Marginal-Attached index were assessed after 4 weeks of intervention and 2 weeks of washout. Thirty patients completed the entire study protocol. We found no increase in salivary secretory immunoglobulin A levels and salivary flow rates in the probiotic group compared with placebo. Baseline and outcome salivary secretory immunoglobulin A concentrations (mg/L) were 226 ± 130 and 200 ± 113 for the probiotic group and 205 ± 92 and 191 ± 97 for the placebo group, respectively. A significant decrease in plaque accumulation was observed in the probiotic group at 4 and 6 weeks. Within the limitations of the present study, it may be concluded that probiotic intake (Streptococcus salivarius K12) does not affect salivation rates and secretory immunoglobulin A salivary levels but exhibits a positive effect on plaque accumulation. Trial registration NCT05039320. Funding: none.

We aimed to assess the effect of oral probiotic containing the Streptococcus salivarius M18 strain on gingival inflammation, bleeding on probing, and oral biofilm. Sixty-one consenting participants aged between 18 and 25 with gingivitis were recruited in this double-blind, parallel-group study and randomly divided into the probiotic group (n = 31) and the placebo group (n = 30). Fifty-seven participants completed the entire study protocol, 27 in the probiotic group and 30 in the placebo group. The outcomes were assessed after 4 weeks of intervention and 4 weeks of follow-up. There was a significant decrease in the Gingival Index, with the effect size of 0.58 [95%CI 0.05–1.10], and Turesky modification of the Quigley and Hein Plaque Index, with the effect size of 0.55 [95%CI: 0.02–1.07], in the probiotic group after the intervention. However, after a 4-week follow-up, the only significant treatment outcome was improved gingival condition according to the Gingival Index. The Gingival Bleeding Index also decreased significantly in the probiotic group after the intervention period; after the follow-up, this parameter did not differ significantly in both groups from the baseline values. In the placebo group, there were no significant improvements in the assessed parameters throughout this study. No serious side effects were registered. Within the limitations of this study, we conclude that the use of oral probiotic containing the Streptococcus salivarius M18 strain resulted in a significant improvement in gingival condition and oral hygiene level in young adults with gingivitis. Trial registration NCT05727436. Funding: none.

This cross-sectional survey assessed the knowledge of and the attitude towards probiotics of dental students and academics at Sechenov University, Moscow, Russia. Our questionnaire consisted of 15 questions divided into 3 sections: respondents’ sociodemographic data, knowledge on probiotics, and attitude towards probiotics. The data were analyzed using the Mann–Whitney U test, Fisher’s exact test, and Spearman’s rank correlation coefficient. Out of the 658 questionnaires distributed, a total of 239 questionnaires were completed by the undergraduates, yielding a response rate of 39.6%, and 54 by the teaching staff (response rate = 100%). Most students (53.6%) and teachers (55.5%) had a fair knowledge of probiotics (p = 0.3135). A vast majority of dental students (97.9%) and all teachers had a positive attitude towards probiotics, with higher mean scores among academics (p < 0.001). A positive weak correlation was found between knowledge and attitude (Spearman r = 0.17, p = 0.0027). The results obtained reveal the need for more evidence-based educational trainings for university teachers and a course on probiotics to be included in the curriculum for dental students.

Background: We compared the camouflage effect of three white spot lesion (WSL) treatments (infiltration, nano-hydroxyapatite (nHAP) remineralization, and microabrasion) and color stability of the treated surfaces. Methods: Fifty sound extracted teeth were used in the study. WSLs were created on 40 buccal dento-enamel specimens through the use of acidic methylcellulose gel. These specimens were randomly assigned to treatment groups (n = 10 per group): negative controls, nano-hydroxyapatite (nHAP), resin infiltration, and microabrasion. After the treatment, all 50 specimens were immersed in coffee for 7 days. Color measurements were performed four times: at baseline (T0), after the demineralization procedure (T1), after the treatments (T2), and after immersion in coffee (T3). Results: No restoration of the initial enamel color was observed in any of the groups. The ICON and MA groups exhibited the highest masking effect, with the mean ΔE_T0-T2 = 7.46, although the differences among the study groups were insignificant. All three treatments increased the resistance of WSLs to discoloration in coffee compared to the negative control group; however, infiltration (∆E_T2-T3 = 4.13) and microabrasion (∆E_T2-T3 = 3.49) showed a better color stability tendency than nHAP remineralization (∆E_T2-T3 = 7.26). Conclusions: Despite its well-known remineralizing and desensitizing effects, nHAP showed the least masking effect for WSLs and lower color stability compared to resin infiltration and microabrasion. However, none of the methods allowed for complete restoration of the original color. After the discoloration procedure, the color changes in the white spots treated with microabrasion and infiltration were comparable to those of the sound enamel.

S. salivarius M18 administration has been proven to provide positive effects on periodontal health; however, there is still no consensus on the optimum duration of probiotic administration. This study aimed to evaluate the effect of three months of probiotic supplementation on bleeding on probing, signs of gingival inflammation, and dental biofilm. Sixty-two eligible individuals with gingivitis were enrolled in this placebo-controlled, double-blind trial and randomly allocated to the M18 or control groups. Primary outcomes were changes in gingival condition (gingival index, GI; gingival bleeding index, GBI) after 1, 2, and 3 months of lozenges administration and after a one-month washout. Secondary outcomes included changes in the Quigley–Hein plaque index (modified by Turesky et al.) after 1, 2, and 3 months of lozenges administration and after a washout. In total, 60 individuals completed the study (31 and 29 in the M18 group and the control group, respectively). No severe adverse events were reported. Probiotic supplementation resulted in a significant decrease in gingival bleeding at 1 month (effect size 1.09 [CI95%: 0.55–1.63]), 2 months (effect size 0.78 [CI95%: 0.26–1.30]), and 3 months (effect size 0.67 [CI95%: 0.15–1.18]) and a significant reduction in dental plaque accumulation at 2 months (effect size 0.63 [CI95%: 0.12–1.14]) and 3 months (effect size 0.55 [CI95%: 0.03–1.05]). A three-month supplementation with the probiotic resulted in a significant reduction in gingival bleeding and biofilm accumulation; however, a long-lasting effect is not expected, indicating the need for probiotic intake on a long-term basis.