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Face masking is associated with self-perceived dry mouth and halitosis. Aim of the study was to measure the effect of different face masks on salivary parameters and halitosis.The randomized controlled crossover clinical trial with four periods included 40 oral healthy participants using different face masks (cloth mask, surgical mask, filtering facepiece 2 [FFP2] mask) or no mask (control) for 4 h in random order. Unstimulated salivary flow rate (primary outcome) and stimulated salivary flow rate, salivary pH and buffer capacity of stimulated and unstimulated saliva (secondary outcomes, blinded), and volatile sulfur compounds (secondary outcome) were measured before and after the 4-h periods. Statistical analysis was performed by repeated measures ANOVA (p 0.05).Of 40 randomized participants, 39 completed the study. Unstimulated salivary flow rate prior to face masking amounted to 0.6 ± 0.3 ml/min. Face masking had no significant effect on unstimulated salivary flow (p = 0.550). Face masking had also no significant effect on the other salivary parameters (p ≥ 0.518). The concentration of volatile sulfur compounds (VSC) prior to face masking amounted to 157.3 ± 59.7 ppb. After face masking, the concentration of VSC increased slightly, but not significantly (p = 0.055): 168.1 ± 76.3 ppb (control), 199.3 ± 132.7 ppb (cloth masks), 188.5 ± 101.1 ppb (surgical masks), and 189.7 ± 90.1 ppb (FFP2 masks).Four hours of face masking did not change the salivary flow rate, pH, and buffer capacity, and had no significant effect on VSC's levels. Wearing face masks does not seem to result in measurable side-effects on salivary parameters such as a reduced salivary flow rate or VSC's levels.The protocol was prospectively registered at ClinicalTrials.gov (NCT04914208) on June 4, 2021.

Less-experienced operators have been shown to require additional training to achieve results similar to those of experienced operators. However, clinical data comparing the survival and success of ceramic restorations by experienced and less-experienced operators by using the computer-aided design and computer-aided manufacturing (CAD-CAM) technology are lacking.The purpose of this retrospective clinical study was to analyze and compare the clinical performance of CAD-CAM lithium disilicate restorations fabricated by less-experienced (predoctoral dental students) and experienced (dentists) operators.Patients who received an adhesively luted CAD-CAM lithium disilicate restoration between 2011 and 2019 were included in the study. Clinical performance was assessed by calibrated examiners by using World Dental Federation (FDI) criteria. Success and survival were calculated by the Kaplan-Meier method and statistically compared by log-rank tests and univariate Cox regression analyses. FDI criteria were compared by using Mann-Whitney-U tests (α=.05).Ninety-two restorations (students: n=65, dentists: n=27) were assessed (mean ±standard deviation time from insertion: 4.04 ±1.55 years). The survival rates after 2 years (students: 93.8%, mean annual failure rate [mAFR]: 3.1%; dentist: 96.3%, mAFR: 1.9%) and after 4 years (students: 87.3%, mAFR: 3.3%; dentists: 88.3%, mAFR: 3.1%) were not significantly different (P=.525). Also, success rates after 2 (students: 90.8%, mAFR: 4.7%; dentists: 92.6%, mAFR: 3.8%) and 4 years (students: 82.4%, mAFR: 4.7%; dentists: 76.1%, mAFR: 6.6%) were not significantly different (P=.778). FDI criteria were also not significantly different between less-experienced and experienced operators (P≥.110).Operator experience did not affect the short-term clinical performance of CAD-CAM lithium disilicate restorations.

Cathepsin K (catK) modulates the degradation of dentin collagen. This study aimed to evaluate the effects of catK inhibitors on dentin erosion. Dentin beams were eroded (4 times/d for 5 d) and immersed in deionized water (negative control), 0.1 M NaCl, 0.3 M NaCl, 0.5 M NaCl, or 1 μM odanacatib (each n = 16) for 30 min after each erosive challenge. Erosive dentin loss (EDL) and demineralized organic matrix (DOM) thickness were evaluated profilometrically. Additionally, dentin beams were demineralized, immersed in the respective solutions for 30 min each (n=5), and then incubated in artificial saliva for 5 d. Dentin collage degradation was evaluated by quantifying the levels of the C-terminal peptide of type I collagen (CTX), C-terminal cross-linked telopeptide of type I collagen (ICTP), and hydroxyproline (HYP) in the incubation media. Significantly lower EDL and dentin collagen degradation (CTX, ICTP, and HYP), and thicker DOM layers were observed in the samples treated with 0.3 M NaCl and 1 μM odanacatib than in those treated with deionized water (all P < 0.05). The samples treated with 1 μM odanacatib showed significantly lower levels of CTX and HYP than those treated with 0.3 M NaCl (all P < 0.05). The present findings support the potential use of catK inhibitors in controlling dentin erosion.

BACKGROUND A successful periodontitis treatment demands good manual skills. A correlation between biological sex and dental students’ manual dexterity is currently unknown. OBJECTIVE This study examines performance differences between male and female students within subgingival debridement. METHODS A total of 75 third-year dental students were divided by biological sex (male/female) and randomly assigned to one of two work methods (manual curettes n=38; power-driven instruments n=37). Students were trained on periodontitis models for 25 minutes daily over 10 days using the assigned manual or power-driven instrument. Practical training included subgingival debridement of all tooth types on phantom heads. Practical exams were performed after the training session (T1) and after 6 months (T2), and comprised subgingival debridement of four teeth within 20 minutes. The percentage of debrided root surface was assessed and statistically analyzed using a linear mixed-effects regression model (P RESULTS The analysis is based on 68 students (both groups n=34). The percentage of cleaned surfaces was not significantly different (P=.40) between male (mean 81.6%, SD 18.2%) and female (mean 76.3%, SD 21.1%) students, irrespective of the instrument used. The use of power-driven instruments (mean 81.3%, SD 20.5%) led to significantly better results than the use of manual curettes (mean 75.4%, SD 19.4%; P=.02), and the overall performance decreased over time (T1: mean 84.5%, SD 17.5%; T2: mean 72.3%, SD 20.8%; P CONCLUSIONS Female and male students performed equally well in subgingival debridement. Therefore, sex-differentiated teaching methods are not necessary.

Aim Repeated dental treatment of patients with intellectual and/or physical disabilities under general anesthesia (GA) often becomes necessary. This study aimed to identify potential risk factors predictive of repeated dental treatment under general anesthesia. Materials and methods Data of adult patients with intellectual and/or physical disabilities receiving dental treatment under GA within a time period of 7 years were analyzed (n = 203, mean age: 41.0 ± 14.9 years). All patients received comprehensive dental treatment (professional tooth cleaning, periodontal therapy, composite restorations, and/or extractions); patients receiving extractions only for emergency dental care were not included as a second intervention for restorative treatment often followed. Demographic, anamnestic, oral health, and treatment factors were obtained from dental records. Duration of intervals without dental treatment under GA was assessed using Kaplan–Meier statistics. Potential predictive factors were tested using univariate and multivariate cox regression analyses. Results Thirty-five patients (17.2%) received a second and five patients (2.5%) a third dental treatment under GA during that period. In the univariate analysis, patients’ age, living situation, and nutrition were associated with repeated GA. In the multivariate Cox regression analysis, only nutrition remained significant. Risk for repeated treatment increased if patients were tube-fed (HR: 7.54, p = 0.001) or received pureed/liquid food (HR: 4.32, p = 0.007) compared to nutrition without limitation. Conclusion In adult patients with intellectual and/or physical disabilities, nutrition affects the risk for repeated dental treatment under GA. Clinical relevance Identification of risk factors making repeated dental treatment under GA of patients with intellectual and/or physical disabilities more likely is essential to adjust preventive measures.

BACKGROUND Scoring and awarding credit are more complex for multiple-select items than for single-choice items. Forty-one different scoring methods were retrospectively applied to 2 multiple-select multiple-choice item types (Pick-N and Multiple-True-False [MTF]) from existing examination data. OBJECTIVE This study aimed to calculate and compare the mean scores for both item types by applying different scoring methods, and to investigate the effect of item quality on mean raw scores and the likelihood of resulting scores at or above the pass level (≥0.6). METHODS Items and responses from examinees (ie, marking events) were retrieved from previous examinations. Different scoring methods were retrospectively applied to the existing examination data to calculate corresponding examination scores. In addition, item quality was assessed using a validated checklist. Statistical analysis was performed using the Kruskal-Wallis test, Wilcoxon rank-sum test, and multiple logistic regression analysis (P RESULTS We analyzed 1931 marking events of 48 Pick-N items and 828 marking events of 18 MTF items. For both item types, scoring results widely differed between scoring methods (minimum: 0.02, maximum: 0.98; PPP=.001). Mean raw scores were higher for MTF items with cues than for those without cues (0.91 vs 0.8; PP=.09). Item quality also impacted the likelihood of resulting scores at or above the pass level (odds ratio ≤6.977). CONCLUSIONS Educators should pay attention when using multiple-select multiple-choice items and select the most appropriate item type. Different item types, different scoring methods, and presence of cues are likely to impact examinees’ scores and overall examination results.

In case of crown fractures after traumatic dental injuries, the affected teeth can be restored either with reattachment of the fractured fragment or with a direct composite restoration. So far, longevity data for reattachments and direct composite restorations with regard to different failure types (pulp necrosis and infection, restoration loss) are scarce. Therefore, the aim of this retrospective study was to evaluate the restorative and biological survival of reattached fragments and composite restorations after crown fractures in permanent teeth.Dental records of patients treated between 2000 and 2018 were retrospectively analysed regarding the restoration (reattachment or direct composite restorations) of teeth with crown fractures. Survival (no further intervention) and restorative and/or biological failure of all restored teeth were recorded. Statistical analysis was performed using Kaplan-Meier statistics, and the mean annual failure rates for two and 5 years were calculated. Furthermore, the effect of potential risk factors on survival was assessed. Log-rank tests and univariate Cox regression models (likelihood ratio tests) were used to assess the univariate effect of all variables of interest. Variables with a p-value ≤.10 were included in a multivariate Cox regression model with shared frailty (p .05).Overall, 164 patients with 235 teeth (uncomplicated crown fracture: N = 201, complicated crown fracture: N = 34) were included (1.6 ± 2.5 years observation time). Of these, 59 teeth were restored with reattachment of the fragment and 176 with a composite restoration. Overall, composite restorations had a significantly higher survival rate than reattachments (p = .002). The cumulative survival after 2 years was 42.9% and 65.0% for teeth treated with a reattachment (mAFR = 34.5%) and a composite restoration (mAFR = 19.3%), respectively. When differentiating between failure types, restoration failure and pulp necrosis were significantly more frequently detected in reattached crown fractures compared to composite restorations (restorative failure: p = .001; biological failure: p = .036). In the multivariate Cox regression model, the variable jaw and luxation significantly influenced the survival when the tooth was restored with a composite restoration. The survival was not influenced by the fracture type.Restorative and biological failures were more frequently detected when the tooth was restored with a reattached fragment compared to a direct composite restoration. Both, restoration failure and pulp necrosis with infection should be considered as frequent complications after restoration of crown-fractured teeth which emphasizes the necessity of regular and short follow-up intervals throughout the first 2 years.

Objectives When managing partially defective restorations, dentists can choose between repair and replacement. We aimed to assess the long-term treatment costs of repairs and replacements. Methods Partially defective anterior and posterior composite restorations in permanent teeth had been repaired or replaced in a German university hospital and were retrospectively followed until censoring or one of the following events: (1) Extraction, (2) Major complications including placement of indirect restorations, endodontic treatments and extractions, or (3) Any complications including major complications and further direct restorations. Costs were estimated from a German mixed public-private-payer perspective. Cost-effectiveness differences were described using median-based incremental-cost-effectiveness ratios (ICERMEDIAN). Statistical analysis was performed using generalized linear mixed modeling (GLM), Chi2-test, and Wilcoxon rank-sum test (p Results A total of 616 repairs in 468 patients (follow-up: 4.9 ± 4.1 years) and 264 replacements in 218 patients (follow-up: 4.8 ± 4.3) were included. While replacements were associated with higher initial treatment costs, median annualized treatment costs did not significantly differ between repair (47.58 Euro [IQR: 24.41–107.04]) and replacement (50.64 Euro [IQR: 26.30–118.78]; p > 0.05), but were higher for molars (75.53 Euro [IQR: 24.41–92.18]) than incisors (45.03 Euro [IQR: 28.19–168.50]; p = 0.011). The difference in the % of extractions, major and any complications were minimal between both groups. The mean ICERMEDIAN of replacement vs. repair was -146.8 Euro/% when extractions were considered as outcomes. Regarding major and any complications, mean ICERMEDIAN amounted to 67.6 Euro/% and 23.9 Euro/%, respectively. Significance Repairs and replacements of partially defective restorations showed similar long-term costs and cost-effectiveness.

Objectives This study aimed to assess the survival of direct composite restorations placed under general anesthesia in adult patients with intellectual and/or physical disabilities. Materials and methods Survival of composite restorations placed under general anesthesia in adult patients with intellectual and/or physical disabilities was retrospectively analyzed. Failure was defined as the need for replacement of at least one surface of the original restoration or extraction of the tooth. Individual-, tooth-, and restoration-related factors were obtained from dental records. Five-year mean annual failure rate (mAFR) and median survival time were calculated (Kaplan-Meier statistics). The effect of potential risk factors on failure was tested using univariate log-rank tests and multivariate Cox-regression analysis (α = 5%). Results A total of 728 restorations in 101 patients were included in the analysis. The survival after 5 years amounted to 67.7% (5-year mAFR: 7.5%) and median survival time to 7.9 years. Results of the multivariate Cox-regression analysis revealed physical disability (HR: 50.932, p = 0.001) and combined intellectual/physical disability (HR: 3.145, p = 0.016) compared with intellectual disability only, presence of a removable partial denture (HR: 3.013, p < 0.001), and restorations in incisors (HR: 2.281, p = 0.013) or molars (HR: 1.693, p = 0.017) compared with premolars to increase the risk for failure. Conclusion Composite restorations placed under general anesthesia in adult patients with intellectual and/or physical disabilities showed a reasonable longevity as 67.7% survived at least 5 years. Clinical relevance Survival of composite restorations depends on risk factors that need to be considered when planning restorative treatment in patients with intellectual and/or physical disabilities. NCT04407520

Controversy exists regarding the effectiveness of delayed toothbrushing in decreasing erosive tooth wear (ETW). The purpose of this systematic review and meta-analysis was to assess the effects of delayed toothbrushing on ETW. This systematic review and meta-analysis was conducted according to the PRISMA statement and registered in PROSPERO (CRD42020200463). PubMed, Embase, and Web of Science databases were systematically searched with no publication year limits. Screening and data extraction were performed independently by two reviewers. In situ and in vitro studies comparing ETW after delayed and immediate toothbrushing following an erosive attack were included. Review Manager software 5.3 (The Cochrane Collaboration, Oxford, UK) was used for statistical analyses. Heterogeneity was assessed with the Cochran Q test and I2 statistics. Of the 565 potentially relevant studies, 26 full-text articles were assessed for eligibility. Twelve articles were included in the systematic review, and 11 were included in the qualitative analyses. No significant difference in the ETW of human enamel was observed between delayed and immediate toothbrushing (P = 0.13), whereas significantly less ETW of bovine enamel was observed after delayed toothbrushing (P

Objectives For an ORCA/EFCD consensus, this systematic review assessed the question “How to intervene in the caries process in proximal caries in adolescents and adults”. Material and methods Separating between the management of initial and cavitated proximal caries lesions, Medline via PubMed was searched regarding non-operative/non-invasive, minimally/micro-invasive and restorative treatment. First priority was systematic reviews or randomized controlled trials (RCTs), otherwise cohort studies. After extraction of data, the potential risk of bias was estimated depending on the study type, and the emerging evidence for conclusions was graded. Results Regarding non-invasive/non-operative care (NOC), no systematic reviews or RCTs were found. In cohort studies (n = 12) with a low level of evidence, NOC like biofilm management and fluoride was associated with a low proportion and slow speed of progression of initial proximal lesions. Minimally/micro-invasive (MI) treatments such as proximal sealants or resin infiltration (four systematic reviews/meta-analyses) were effective compared with a non-invasive/placebo control at a moderate level of evidence. Data on restorative treatment came with low evidence (5 systematic reviews, 13 RCTs); with the limitation of no direct comparative studies, sample size-weighted mean annual failure rates of class II restorations varied between 1.2 (bulk-fill composite) and 3.8% (ceramic). Based on one RCT, class II composite restorations may show a higher risk of failure compared with amalgam. Conclusions Proximal caries lesions can be managed successfully with non-operative, micro-invasive and restorative treatment according to lesion stage and caries activity. Clinical relevance Proximal caries treatment options like non-operative, micro-invasive and restorative care should be considered individually.

Introduction This retrospective study aimed to analyze the effect of repairing endodontic access cavities with composite on the survival of single crowns and retainer restorations of fixed or removable dental prostheses. Methods Dental records of patients attending a university dental clinic were retrospectively screened for single crowns and retainer restorations receiving endodontic treatment after crown placement. Survival (no further intervention) and failure (removal, loss or replacement of crown, replacement of access restoration, or recementation of restoration) of crowns and retainers with repaired endodontic access cavities were recorded. The mean annual failure rates were calculated, and the effect of individual-, tooth-, and restoration-related variables on survival was assessed by univariate log-rank tests and multivariate Cox regression analyses with shared frailty (P Results One hundred eighty repaired crowns/retainers placed in 151 patients were included (4.5 ± 3.3 years follow-up). Survival after 2, 5, 7, and 10 years amounted to 82.7%, 71.5%, 67.3%, and 48.8% (mean annual failure rate = 9.0%, 6.5%, 5.5%, and 6.9%), respectively. Although tooth type, kind of restoration, endodontic irrigant, repair conditioning methods, and kind of composite affected survival in the univariate regression analyses, only the kind of restoration (single crown vs retainer restoration) remained significant in the multivariate Cox regression model. Conclusions Repairing endodontic access cavities with composite increases the longevity of single crowns and retainer restorations.

BACKGROUND Smoking is one of the world's major health problems and dental professionals are in a unique position to promote smoking cessation. However, according to the current literature, neither dental students nor dentists feel adequately prepared to counsel smokers. The purpose of this study was to develop and implement a teaching intervention on smoking cessation for fourth-year dental students and assess its effectiveness in terms of learning outcome on knowledge, communication skills and attitudes. MATERIALS AND METHODS In this prospective intervention study, students in the intervention group (n = 28) participated in a teaching module consisting of a podcast, an interactive lecture, a seminar, and small-group sessions with role-play interactions. Knowledge, communication skills and attitudes were measured using written examinations and an objective structured clinical examination (OSCE) at the end of the module and 6 months later. Results were compared with data from a historical control group (n = 27) receiving standard teaching. RESULTS Compared with the control group, students in the intervention group had higher scores in the knowledge test (67.1% vs 41.8%; P

Contains fulltext : 154871.pdf (Publisher’s version ) (Closed access) OBJECTIVE: Due to an increased focus on erosive tooth wear (ETW), the European Federation of Conservative Dentistry (EFCD) considered ETW as a relevant topic for generating this consensus report. MATERIALS AND METHODS: This report is based on a compilation of the scientific literature, an expert conference, and the approval by the General Assembly of EFCD. RESULTS: ETW is a chemical-mechanical process resulting in a cumulative loss of hard dental tissue not caused by bacteria, and it is characterized by loss of the natural surface morphology and contour of the teeth. A suitable index for classification of ETW is the basic erosive wear examination (BEWE). Regarding the etiology, patient-related factors include the pre-disposition to erosion, reflux, vomiting, drinking and eating habits, as well as medications and dietary supplements. Nutritional factors relate to the composition of foods and beverages, e.g., with low pH and high buffer capacity (major risk factors), and calcium concentration (major protective factor). Occupational factors are exposition of workers to acidic liquids or vapors. Preventive management of ETW aims at reducing or stopping the progression of the lesions. Restorative management aims at reducing symptoms of pain and dentine hypersensitivity, or to restore esthetic and function, but it should only be used in conjunction with preventive strategies. CONCLUSIONS: Effective management of ETW includes screening for early signs of ETW and evaluating all etiological factors. CLINICAL RELEVANCE: ETW is a clinical condition, which calls for the increased attention of the dental community and is a challenge for the cooperation with other medical specialities.

Introduction Aim was to analyze and compare the efficacy of different bleaching agents typically used for internal bleaching of endodontically-treated discolored teeth. Methods Electronic databases (PubMed, Web of Science, Cochrane Library) were searched by two reviewers for clinical trials in which the color of endodontically-treated discolored teeth, before and after internal bleaching, was examined using shade guide units (ΔSGU) or a spectrophotometer/colorimeter (ΔE). The efficacies of the bleaching agents were compared using subgroup analyses. Statistical heterogeneity was assessed with Cochran’s Q and I2-statistic. Publication bias was evaluated using funnel-plots. Results Eight studies were included in the systematic review, out of which six could be included in the meta-analyses. Internal bleaching led to a significant change in tooth shade (ΔSGU: 6.27 [95%-CI: 5.36–7.17], ΔE: 12.83 [95%-CI: 9.46–16.20]). With regard to ΔSGU, the use of carbamide peroxide (35% or 37%), hydrogen peroxide (35%), and the combination of sodium perborate and hydrogen peroxide (3% or 30%) led to better bleaching effect than did sodium perborate (padj.≤0.026). Regarding ΔE, there were no significant differences between carbamide peroxide (37%), hydrogen peroxide (35%) and sodium perborate mixed with hydrogen peroxide (p=0.051). Risk of bias of included studies was classified as moderate to high. Conclusions Carbamide peroxide, hydrogen peroxide, and sodium perborate have a significant bleaching effect on discolored, root-canal-treated teeth. For a valid assessment of shade stability and comparison of bleaching agents resp. their concentrations, further studies with long term recalls are necessary.

The study aimed to apply micro-computed tomography (micro-CT) and transverse microradiography (TMR) to measure dentine demineralization and to test the preventive effect of titanium tetrafluoride (TiF4 ) under microcosm biofilm. Sound dentine specimens from bovine root were treated for 6 h with: (i) 4.0% titanium tetrafluoride (TiF4 ) varnish [pH 1.0, 2.45% fluoride (F-); (ii) 5.42% sodium fluoride (NaF) varnish (pH 5.0, 2.45% F); (iii) 2% chlorhexidine (CHX) gel (pH 7.0); (iv) placebo varnish (pH 5.0); or (v) no agent (untreated). Dentine specimens were then exposed to human saliva mixed with McBain saliva for 8 h. Thereafter, McBain saliva containing 0.2% sucrose was applied daily, for 5 d, onto dentine specimens to stimulate formation of microcosm biofilm. Although a high correlation was found between the results of both methods regarding integrated mineral loss, the results of the methods did not show good agreement in Bland-Altman plots, with significant biases in calculations of lesion depth. Fluoride varnishes were able to reduce dentine demineralization (P < 0.05), while CHX failed to do so. Fluorides are still the best option to reduce dentine demineralization. Micro-CT may be used to measure dentine mineral loss, but not the lesion depth, for which TMR is superior.

While repairs are increasingly recommended to manage partially defective restorations, performing the repair (including bonding to different substrates) can be challenging, and dentists should adhere to established repair protocols. We aimed to systematically assess the consistency and quality of repair protocols.808 records were initially identified and 71 repair protocols based on 84 sources included. The number of published sources over time increased exponentially (p 0.001). Recommended treatment steps varied widely. Some treatment steps were only recommended by a minority of protocols, while others were consistently recommended (e.g. surface roughening, hydrofluoric acid etching of silicate ceramics, application of an adhesive/bonding agent). The overall quality of included sources was moderate (mean ± SD 3.7 ± 0.9 out of 7 points).Electronic databases (Medline via PubMed, Embase) were searched, hand searches using Google and Google Scholar conducted, and the reference lists of included full texts screened and cross-referenced.(Non-)systematic reviews, working instructions, and textbooks with protocols on direct composite repair restorations for partially defective (1) composite, (2) amalgam, (3) porcelain-fused-to-metal (PFMs) with exposed metal base, (4) ceramic/PFMs without exposed metal base, and (5) full metal restorations were included. Data synthesis was performed by tabulation of recommended treatment steps and descriptive statistics. The quality of included sources was assessed based on a checklist for guideline appraisal (MiChe).The main treatment steps were consistently reported across repair protocols.Dentists may want to adopt widely recommended treatment steps when performing repairs of different restoration materials in their daily practice.

This study evaluated the effect of three different NiTi instrumentation techniques on the incidence of microcracks after the preparation of straight and curved root canals using micro-CT. Roots from mandibular premolars and maxillary molars (n = 66) with the same mean canal curvatures were assigned to three groups of straight and three groups of curved roots (n = 11). After preoperative micro-CT scans, root canals were prepared with Reciproc, OneShape and ProTaper Next to size 25. Specimens were scanned again, and pre- and post-operative cross-sectional images (n = 75 263) were screened to identify the presence of dentinal microcracks. Overall, microcracks were detected in 2.97% (n = 2236) of the cross-sectional images. No new dentinal microcracks were observed after root canal instrumentation of straight and curved canals with the tested NiTi systems. Instrumentation with Reciproc, OneShape and ProTaper Next did not induce the formation of dentinal microcracks irrespective of canal curvature.

The aim of this systematic review and meta-analysis was to compare the bond strength between eroded and sound permanent enamel and dentin and to assess whether bonding performance (immediate and after aging) differs between etchrinse and self-etch adhesives and can be improved by surface pretreatment prior to bonding.Electronic databases (PubMed, Scopus, Embase, Web of Science, CENTRAL, LILACS, BBO) were searched by two reviewers. Random-effect meta-analyses were performed to compare bond strength to sound and eroded dental hard tissues without and with surface pretreatment prior to bonding, respectively. The effect of adhesive mode (etchrinse vs. self-etch) and aging (immediate vs. aged) was compared using subgroup analyses. Statistical heterogeneity was assessed using Cochran's Q and IFourty-seven studies (45 in vitro, 2 in situ) were included in the systematic review and meta-analyses. Erosion impairs bond strength to dentin (p0.001; mean difference: -10.2 MPa [95%CI: -11.9 to -8.6 MPa]), but not to enamel (p = 0.260). Surface pretreatment measures removing or stabilizing the collagenous matrix can improve dentin bond strength (maximum mean difference: +12.4 MPa). Etchrinse and self-etch adhesives did not perform significantly different on eroded enamel (p = 0.208) and dentin (p = 0.353). The majority of studies (32 of 47) presented a medium risk of bias.Data from in vitro and in situ studies showed that erosion impairs dentin bonding of etchrinse and self-etch adhesives and makes surface pretreatment prior to bonding of composite restorations necessary.

This study aimed to analyse if the erosion-protective potential of the salivary pellicle is different between female and male subjects. Bovine enamel and dentin specimens (each n = 3) were exposed to the oral cavity of healthy female or male volunteers (each n = 25, females: 25.8 ± 3.5 years, males: 26.7 ± 4.0 years) for 120 min to form a salivary pellicle. Subsequently, each 2 enamel and 2 dentin specimens were eroded with hydrochloric acid (pH 2.6, 60 s). Specimens of the control group (each n = 30) were eroded without presenting a salivary pellicle. Calcium release into the acid was determined photometrically. Additionally, total protein content in the pellicle (each n = 1 enamel and dentin specimen/volunteer) and different salivary parameters (flow rate, pH, buffer capacity, protein, albumin, calcium, phosphate, fluoride) were assessed. Statistical analyses were performed by one-way ANOVA, t tests, multiple linear regressions and Pearson correlations (p < 0.05). The erosion-protective capacity was not significantly different among female (calcium release [% of control]: enamel: 82.6 ± 28.1, dentin: 80.7 ± 24.0) and male (enamel: 76.0 ± 27.5, dentin: 87.1 ± 34.9) subjects. The protein content of the pellicle was not different between female and male subjects. The protein content and pH of unstimulated saliva were significantly reduced in female compared to male volunteers. Calcium release was neither correlated with the protein content of the salivary pellicle nor with salivary parameters. Under the conditions of the present study, the erosion-protective capacity of the salivary pellicle of female and male subjects is not different.

Manufacturers offer single-file instrumentation systems with matching gutta-percha (GP) cones to simplify root canal preparation and obturation. The purpose of this study was to determine whether file diameters and tapers match with corresponding cone diameters and tapers (precision) as well as industry standards (accuracy).Twenty files and corresponding GP cones from each size of F360 (#25, #35, #45, #55 with .04 taper) and Reciproc (#25, #40, #50 with variable tapers) instruments were examined by using optical microscopy (×32) to determine their diameter and taper. Precision was evaluated by using one-way analysis of variance (α = 0.05) with Scheffé post hoc tests and t tests with Bonferroni correction. Accuracy was calculated by subtracting the nominal values from the measured values of all files and GP cones, and mean diameter and taper differences were compared by using one-way analysis of variance (α = 0.05) and Scheffé post hoc test for pairwise comparison.For F360, the majority of file and cone diameters were within the tolerance levels, but most of the file diameters were significantly larger than GP cone diameters (P .05), but the majority of all measured values were within the tolerance levels. For Reciproc, file and cone diameters at D1 and D3 mostly approached the nominal values. At the coronal end, file diameters #25 and #50 were significantly smaller than cone diameters (P .05). For both instrumentation systems, almost all file and cone tapers matched with the preset tolerance ranges. For Reciproc, significant differences between file and GP cone demonstrated either smaller cone or smaller file diameters and tapers, depending on the size. Most of the measured values were within the acceptable range, but diameters at the coronal end exhibited the highest percent difference from the nominal values.Despite the call for standardization, variability in diameter and taper dimensions between single-file instrumentation systems and their corresponding GP cones can be expected.

Objectives To identify potential changes in various aspects of teaching and to ascertain whether previously found inconsistencies in the teaching of criteria, indications and operative techniques for the repair of defective composite restorations at German dental schools have been resolved. Methods A validated questionnaire was used to gain the information sought. It was sent to all dental schools in Germany (n = 30). Whenever possible, data were compared to previous studies conducted in 2000 and 2009. Statistical analysis was performed using Fisher’s exact tests (p Results Twenty-nine schools responded to the survey – a response rate of 97%. All respondents indicated positive experiences with the repair of restorations. The teaching of repairs in 2018 (90%) was found to be comparable to the findings from the 2009 survey (88%, p = 1.000), but significantly increased since the 2000 survey (50%, p = 0.006). Main reasons reported for teaching repairs are tooth substance preservation (97%) and reduction of pulpal damage (79%). Main clinical indications are marginal defects and secondary caries. When performing repairs, almost all dental schools were found to teach both mechanical and adhesive substrate surface conditioning. Marked variation was observed in the method of mechanical surface treatment, with air abrasion having gained widespread popularity. The average expected longevity of repairs was 7.4 ± 3.0 years. Conclusions The teaching of the repair of resin composite restorations is widespread in dental schools in Germany. Aspects of this teaching were found to be more consistent between dental schools than in previous surveys, albeit variation in operative techniques still exists. Clinical significance Graduates from dental schools in Germany may be found to be well equipped with the knowledge and skills to perform repairs of defective resin based composite restorations in clinical practice.

INTRODUCTION Various scoring approaches for Multiple True-False (MTF) items exist. This study aimed at comparing scoring results obtained with different scoring approaches and to assess the effect of item cues on each scoring approaches' result. MATERIALS AND METHODS Different scoring approaches (MTF, Count-2, Count-3, "Vorkauf-Method," PS50 , Dichotomized MTF, "Blasberg-Method," Multiple response (MR), Correction for Guessing, "Ripkey-Method," Morgan-Method, Balanced Scoring Method) were retrospectively applied to all MTF items used within electronic examinations of undergraduate dental students at the University Medical Center Gottingen in the winter term 2016/2017 (1297 marking events). Item quality was evaluated regarding formal parameters such as presence of cues and correctness of content. Differences between scoring results of all scoring approaches and the differences between each methods' scoring results of items with and without cues were calculated by Wilcoxon rank sum tests (P

Intraoral local anesthetics are widely used for performing painless dental treatments; however, in some cases, they may cause ocular complications such as meiosis, diplopia, nystagmus, ophthalmoplegia, ptosis, and amaurosis. Mostly, the symptoms disappear after several hours; rarely, they have a prolonged character. We describe the case of a 38-year-old young man who had reduced vision in the left eye 5 days after having received intraoral local anesthesia. A diagnosis of cilioretinal artery occlusion with optic disc swelling was made. Ten weeks later, the patient’s visual acuity had increased to 20/20, and the swelling of the optic disc had subsided. Although various possible mechanisms for ocular complications after intraoral local anesthetic administration were suggested in the literature, the exact etiology remains unclear. In this case, inadvertent intravascular injection is believed to be the cause.

AIM To evaluate ex vivo the efficacy of ProTaper Universal Retreatment files (Dentsply Sirona, Ballaigues, Switzerland) in removing Thermafil, GuttaCore (both Dentsply Sirona) or vertically compacted gutta-percha from curved root canals using micro-CT. METHODOLOGY Sixty curved molar roots with the same mean canal curvatures and radii in two directions were prepared using ProFile instruments (Dentsply Sirona) to size 30 with .04 taper and obturated with either Thermafil, GuttaCore or vertically compacted gutta-percha and AH Plus (n = 20). Specimens were retreated using the ProTaper Universal Retreatment files D1, D2 and D3 to working length, and root canal preparation was completed with ProTaper Next (Dentsply Sirona) to size ×4. Percentages of residual filling material and dentine removal were assessed using micro-CT imaging. Working time and procedural errors were recorded. Statistical analysis was performed using Kruskal-Wallis and Wilcoxon tests. RESULTS No significant differences between carrier-based and warm vertical compaction regarding residual filling material (14.2-19.3%) and dentine removal (2.7-3.2 mm3 ) were detected (P > 0.05). Time to reach working length was significantly faster for canals filled with GuttaCore than that observed for Thermafil and warm vertical compaction (P

Objectives Repair instead of complete replacement is recommended to manage partially defective restorations. It is unclear if and why such treatment is taught at dental schools or practiced by dentists. We aimed to identify barriers and facilitators for repairs using a systematic review and meta- and qualitative analysis. Sources Electronic databases (PubMed, CENTRAL, Embase, PsycINFO) were searched. Study selection Quantitative studies reporting on the proportion of (1) dentists stating to perform repairs, (2) dental schools teaching repairs, (3) failed restorations having been repaired were included. We also included qualitative studies on barriers/facilitators for repairs. Random-effects meta-analyses, meta-regression and a thematic analysis using the theoretical domains framework were conducted. Data 401 articles were assessed and 29, mainly quantitative, studies included. 7228 dentists and 276 dental schools had been surveyed, and treatment data of 30,172 restorations evaluated. The mean (95% CI) proportion of dentists stating to perform repairs was 71.5% (49.7–86.4%). 83.3% (73.6–90.0%) of dental schools taught repairs. 31.3% (26.3–36.7%) of failed restorations had been repaired. More recent studies reported significantly more dentists to repair restorations (p = 0.004). Employment in public health practices and being the dentist who placed the original restoration were facilitators for repairs. Amalgam restorations were repaired less often, and financial aspects and regulations came as barriers. Conclusions While most dentists state to perform repairs and the vast majority of dental schools teach repairs, the proportion of truly repaired restorations was low. A number of interventions to implement repair in dental practice can be deduced from our findings. Clinical significance Partially defective restorations are common in dental practice. While repairs are taught and dentists are aware of the recommendation towards repairs, the actually performed proportion of repairs seems low.

Multiple-True-False questions are one specific type of multiple-choice item that can be used to assess knowledge in written examinations. Within Multiple-True-False items, a number of statements within a single item are given, and each statement has to be marked separately as true or false. Various scoring methods for Multiple-True-False items exist and there is no consensus as to the ideal scoring method. The study aimed to systematically identify available scoring methods for Multiple-True-False items and to assess their usability and statistical parameters (i.e. available information included and expected chance scores from random guessing). Another objective was to examine the relation between examinees’ true knowledge and expected scoring results. Data presented in this manuscript may help educators make informed choices about the scoring method to be selected and corresponding pass marks required for testing a certain level of true knowledge of examinees.

This study aimed to analyze bond strengths of self-adhesive flowable composites on enamel, dentin and nano-hybrid composite. Enamel, dentin and nano-hybrid composite (Venus Diamond, Heraeus Kulzer, Germany) specimens were prepared. Three self-adhesive composites (Constic, DMG, Germany; Fusio Liquid Dentin, Pentron Clinical, USA; Vertise Flow, Kerr Dental, Italy) or a conventional flowable composite (Venus Diamond Flow, Heraeus Kulzer, Germany, etchrinse technique) were applied to enamel and dentin. Nano-hybrid composite specimens were initially aged by thermal cycling (5000 cycles, 5-55 °C). Surfaces were left untreated or pretreated by mechanical roughening, Al

SUMMARY Objectives: The aim of this study was to evaluate microleakage and shear bond strength of composite restorations under different cycling conditions. Methods and Materials: Class V cavities were prepared in the buccal and lingual surfaces of 30 human molars (n=60). A further 60 molars were used to prepare flat enamel and dentin specimens (n=60 each). Cavities and specimens were divided into six groups and pretreated with an adhesive (self-etch/Clearfil SE Bond or etch-and-rinse/Optibond FL). Composite was inserted in the cavities or adhered to the specimens' surfaces, respectively, and submitted to cycling (control: no cycling; thermal cycling: 10,000 cycles, 5°C to 55°C; thermal/erosive cycling: thermal cycling plus storage in hydrochloric acid pH 2.1, 5 minutes, 6×/day, 8 days). Microleakage was quantified by stereomicroscopy in enamel and dentin margins after immersion in silver nitrate. Specimens were submitted to shear bond strength testing. Statistical analysis was done by two-way analysis of variance and Kruskal-Wallis tests (p Results: Microleakage in enamel margins was significantly lower in the control group compared with thermal cycling or thermal/erosive cycling. Erosive conditions increased microleakage compared with thermal cycling (significant only for Clearfil SE Bond). No significant differences were observed in dentin margins. Bond strength of enamel specimens was reduced by thermal cycling and thermal/erosive cycling when Clearfil SE Bond was used and only by thermal/erosive cycling when Optibond FL was used. No differences were observed among dentin specimens. Conclusions: Thermal/erosive cycling can adversely affect microleakage and shear bond strength of composite resin bonded to enamel.