Objective To analyze the loss of abutment teeth for double crown-retained removable partial dentures (DC-RPDs) compared to clasp-retained removable partial dentures (C-RPDs). Method and materials A search was conducted in the Ovid MEDLINE, Embase, Web of Science databases, and a manual search. The search was conducted based on the PICO framework with inclusion and exclusion criteria. After extracting the data of selected studies, a meta-analysis was performed to estimate abutment loss with 95% confidence interval (CI). The statistical significance was defined as P  less then  .05, and the heterogeneity of the data was assessed based on the chi-squared test and I2 statistics. Risk of bias assessment was conducted using Cochrane Risk of Bias tool and Newcastle-Ottawa Scale. Results A total of 4,692 records were identified from electronic databases and 38 studies were included for quantitative synthesis of 3,393 subjects with 13,552 abutment teeth. A total of 1,226 abutment teeth were lost with > 4,016 RPDs. me was not a significant factor for C-RPDs (P = .1). None of the included studies were at high risk of bias. Conclusion Within the limitations of the current systematic review and meta-analysis, abutment loss was not significantly different between C-RPDs and DC-RPDs. A significant predictor was follow-up time for DC-RPDs, whereas this factor was not significant for C-RPDs. Further research is needed to investigate critical factors for abutment loss with RPDs.Objective The aim was to evaluate the efficacy of periodontal regenerative therapy using enamel matrix derivatives (EMDs) in aggressive periodontitis patients, and to determine the contribution of maintenance via periodic supportive periodontal treatment. Method and materials In total, 28 patients were evaluated, comprising 74 intrabony sites. In 50 sites EMD gel was applied, and in 24 sites EMD was combined with deproteinized bovine xenograft. Patients were assigned to a supportive periodontal treatment program; 18 patients fulfilled the program, defined as the well-maintained (WM) group; 10 did not comply, defined as the nonmaintained (NM) group. Probing depth (PD), clinical attachment level (CAL), and radiographic bone level (BL) were recorded. Data were compared presurgically (T0), 6 months postsurgery (T1), and 3 to 10 years posttreatment (T2). Results Both surgical modalities achieved similar PD reduction, CAL gain, and BL gain, maintained over time. T1 to T2 showed a mean gain/loss of 0.21 ± 0.5 mm and 0.04 ± 1.1 mm, and -0.65 ± 3.0 mm and -0.73 ± 3.0 mm for PD and CAL, respectively, at the WM/NM groups, respectively. BL gain was 21.6% and 11.5% for the WM/NM groups, respectively (P  less then  .05). The courses of the PD, CAL, and BL differed between the WM and NM groups during the observation periods (P  less then .05). Conclusion Periodontal regeneration via EMD with/without the combination of deproteinized bovine xenograft can be maintained in aggressive periodontitis cases. It appears that periodic supportive periodontal treatment is a determinant factor in achieving this task.Objective This study aimed to examine and compare the anti-caries effects of slightly acidic 1% NaF-HF gel when applied once or twice (7-day or 6-month interval) to mandibular first molars in 6- to 7-year-old children. Method and materials This was a 1-year, multi-arm, placebo-controlled, double-blind, parallel-group randomized trial. In total, 1,077 schoolchildren from eight primary schools were allocated to one of the four study groups (group 1, single application; group 2, two applications with a 7-day interval; group 3, two applications with a 6-month interval; group 4, placebo control). The occlusal surfaces of permanent mandibular first molars were examined by three calibrated examiners who were blind to the group allocation at baseline and the end of the study. Caries reduction and prevented fraction was assessed. Results A total of 986 children completed the study. There was a statistically significant difference in the mean D1MFT increment across the groups (P  less then  .001). HA15 in vitro The mean D1MFT increment was 0.37 in group 1 (single application), 0.18 in group 2 (two applications with a 7-day interval), 0.21 in group 3 (two applications with a 6-month interval), and 0.56 in the control group. The mean D2MFT increments (0.22 in group 1, 0.06 in group 2, 0.18 in group 3, and 0.50 in the control group) also showed a statistically significant difference across the groups (P  less then  .001). Conclusion Subacidic 1% NaF-HF gel exerts a high preventive effect on caries (more than 40%) when applied twice at a 7-day interval in 6- to 7-year-old schoolchildren who do not use fluoride toothpaste in areas where drinking water is not fluoridated.Oral squamous cell carcinoma (OSCC) is an extremely rare occurrence during pregnancy. OSCC accounts for less than 2% of all malignancies in pregnant women, with an average mortality rate of 36%. Understanding the features of this tumor during pregnancy is important; however, the paucity of reports in the literature makes this challenging. Case presentation The following is a case presentation of a woman who was diagnosed with SCC of the tongue (TSCC) at 13 weeks gestation. The article also provides a review of the literature of TSCC affecting pregnant women aged 30 years and under. Conclusion Although OSCC in young women of reproductive age is rare, recent literature suggests an increased risk for this age group. The rarity of OSCC in pregnancy may potentially lead to low clinical index of suspicion, misdiagnosis, and delay in treatment. Additionally, treatment modalities, prognosis, and the long-term impact on the developing fetus are not well established, due to rarity of OSCC in pregnancy. Further studies to identify specific etiologic factors are needed to establish the association of OSCC with pregnancy, aid in prevention, and improve treatment and outcome.Objective This study examined the impact of early biofilm on the tooth surface, during the assessment of initial enamel erosion using swept-source optical coherence tomography (SS-OCT). Method and materials Forty-five enamel windows of 2 × 4 mm2 were prepared on 23 extracted human teeth. The specimens were exposed to citric acid (pH 3.2) for 30 minutes and randomly divided into three groups (n = 15) Group 1, no biofilm; Group 2, 1-day-old biofilm; and Group 3, 3-day-old biofilm. Specimens in Groups 2 and 3 were inoculated with oral bacteria (Streptococcus sanguinis, Streptococcus mitis, and Actinomyces naeslundii) to produce early laboratory-cultivated biofilms for 1 and 3 days respectively. Surface microhardness (SMH) measurements were taken at pre- (t1) and post-erosion (t2); and SS-OCT scans were done at t1, t2, and post-biofilm cultivation (t3). Integrated reflectivity (IR) of the tooth-air interface (IRsurface) and enamel (IRenamel) were computed from the mean A-scans. Statistical analysis was performed using paired t tests and one-way ANOVA (α = .