Usage of Multiple-Choice Items in Summative Examinations: Questionnaire Survey Among German Undergraduate Dental Training Programmes

BACKGROUND

Multiple-choice examinations are frequently employed among German dental schools. However, details regarding the used item types and applied scoring methods are lacking.

OBJECTIVE

We aimed to gain an insight into the current usage of multiple-choice items (ie, questions) in summative examinations in German undergraduate dental training programmes.

METHODS

A paper-based 10-item questionnaire regarding the employed assessment methods, multiple-choice item types, and applied scoring methods was designed. The pilot-tested questionnaire was mailed to the Deans of Studies and to the Heads of Department of Operative/Restorative Dentistry at all 30 dental schools in Germany in February 2023. Statistical analysis was performed using Fisher's exact test (P<.05).

RESULTS

The response rate amounted to 90.0% (27/30 dental schools). All respondent dental schools employed multiple-choice examinations for summative assessments. Examinations were delivered electronically by 70.4% (19/27) of the dental schools. Almost all dental schools used single-choice Type A items (88.9%) which accounted for the largest number of items in about half of the dental schools. Further item types (eg, conventional multiple-select items, Multiple-True-False, Pick-N) were only used by fewer dental schools (≤66.7%, up to 18 out of 27 dental schools). For the multiple-select item types, the applied scoring methods varied considerably (ie, awarding [intermediate] partial credit, requirements for partial credit). Dental schools with the possibility of electronic examinations used multiple-select items slightly more often (73.7%, 14/19 vs. 50.0%, 4/8). However, this difference was statistically not significant (P=.375). Dental schools used items either individually or as key feature problems consisting of a clinical case scenario followed by a number of items focusing on critical treatment steps (55.6%, 15/27). Not a single school employed alternative testing methods (eg, answer-until-correct). A formal item review process was established at about half of the dental schools (55.6%, 15/27).

CONCLUSIONS

Summative assessment methods among German dental schools vary widely. Especially, a large variability regarding the use and scoring of multiple-select multiple-choice items was found.

CLINICALTRIAL

Anamnestic risk factors for erosive tooth wear: Systematic review, mapping, and meta-analysis

OBJECTIVES

Erosive tooth wear is a multifactorial condition. The aim of this systematic review and meta-analysis was to identify key risk factors for erosive tooth wear in permanent dentition.

STUDY SELECTION

Observational studies reporting anamnestic risk factors for erosive tooth wear. Methodological quality and risk of bias were assessed using the modified Newcastle-Ottawa scale for cross-sectional studies. Risk factors were visually presented in a heatmap, and where possible, random-effects meta-analyses were performed for the odds ratios (ORs) of risk factors.

SOURCES

Electronic databases (MEDLINE, Embase, Scopus, and Web of Science) and manual searches in February 2023. The protocol was registered in PROSPERO (CRD4202339776).

DATA

A total of 87 publications reporting on 71 studies were included in the systematic review. The studies examined a variety of anamnestic risk factors (n = 80) that were categorized into ten domains (socio-demographics, socio-economics, general health, oral diseases, medication, oral hygiene, food, beverages, dietary habits, and leisure-related risk factors). Meta-analyses revealed significant associations between erosive tooth wear and male gender (padj.<0.001; OR=1.30, 95 % CI: 1.16-1.44), regurgitation (padj.=0.033; OR=2.27, 95 % CI: 1.41-3.65), digestive disorders (padj.<0.001; OR=1.81, 95 % CI: 1.48-2.21), consumption of acidic foods (padj.=0.033; OR=2.40, 95 % CI: 1.44-4.00), seasoning sauces (padj.=0.003; OR=1.28, 95 % CI: 1.13-1.44), nutritional supplements (padj.=0.019; OR=1.73, 95 % CI: 1.28-2.35), and carbonated drinks (padj.=0.019; OR=1.43, 95 % CI: 1.17-1.75). Most included studies exhibited low bias risk.

CONCLUSIONS

Observational studies investigated a variety of anamnestic risk factors for erosive tooth wear. Future studies should employ validated questionnaires, particularly considering the most important risk factors.

CLINICAL SIGNIFICANCE

Erosive tooth wear is a prevalent condition. Clinicians should concentrate primarily on symptoms of gastroesophageal reflux disease and dietary factors when screening patients at risk for erosive tooth wear.

Effect of different brushing parameters on erosive tooth wear in primary bovine enamel and dentin

This in-vitro study aimed to analyse the effect of brushing and different brushing parameters (kind of toothpaste, kind of toothbrush, brushing force) on erosive tooth wear of primary bovine enamel and dentin. Specimens were prepared from primary bovine enamel or dentin (each group n = 12) and cyclically eroded (6 × 60 s/d, citric acid, pH 2.4) and brushed with children's toothbrushes (2 × 15 s/d) over 5 days. The brushing parameters under investigation were: toothpaste (fluoridated, fluoride-free), toothbrush (manual; rotating-oscillating and sonic, each at two different activation modes) and brushing force (1 N, 2 N). Specimens that were only eroded and not brushed served as controls. Enamel and dentin wear was quantified using widefield confocal microscopy. Statistical analysis was performed using three- and one-way ANOVAs followed by Scheffe's (enamel) or Tamhane's (dentin) post-hoc tests (p < 0.05). Brushing with the fluoridated toothpaste was able to significantly reduce erosive wear in enamel (by 15 to 37%, 6 of 10 groups) and in dentin (by 58 to 72%, all groups), while brushing with the fluoride-free toothpaste was not different from the controls. Considering the kind of toothpaste and brushing force, slight differences between the toothbrushes were observed in enamel, but not in dentin. Within the same toothbrush and activation mode, almost no differences between 1 and 2 N brushing force were detected. In conclusion, erosive tooth wear on primary bovine dental hard tissue mainly depends on the kind of toothpaste, rather than on the kind of toothbrush and the brushing force.

Quality of Patient-Centered eHealth Information on Erosive Tooth Wear: Systematic Search and Evaluation of Websites and YouTube Videos

BACKGROUND

Due to the declining prevalence of dental caries, noncarious tooth defects such as erosive tooth wear have gained increased attention over the past decades. While patients more frequently search the internet for health-related information, the quality of patient-centered, web-based health information on erosive tooth wear is currently unknown.

OBJECTIVE

This study aimed to assess the quality of patient-centered, web-based health information (websites and YouTube videos) on erosive tooth wear.

METHODS

German-language websites were systematically identified through 3 electronic search engines (google.de, bing.de or yahoo.de, and duckduckgo.com) in September 2021. Eligible websites were independently assessed for (1) technical and functional aspects via the LIDA instrument, (2) readability via the Flesch reading-ease score, (3) comprehensiveness of information via a structured checklist, and (4) generic quality and risk of bias via the DISCERN instrument by 2 different reviewers. An overall quality score (ie, higher scores being favored) generated from all 4 domains was used as the primary outcome. Quality scores from each domain were separately analyzed as secondary outcomes and compared by the Friedman test. The effect of practice-specific variables on quality scores of websites from private dental offices was assessed using generalized linear modeling. Eligible YouTube videos were judged based on (1) the comprehensiveness of information, (2) viewers' interaction, and (3) viewing rate. The comprehensiveness of information was compared between websites and YouTube videos using the Wilcoxon rank-sum test.

RESULTS

Overall, 231 eligible websites and 7 YouTube videos were identified and assessed. The median overall quality of the websites was 33.6% (IQR 29.8%-39.2%). Secondary outcome scores amounted to 64.3% (IQR 59.8%-69.0%) for technical and functional aspects, 40.0% (IQR 34.0%-49.0%) for readability, 11.5% (IQR 3.9%-26.9%) for comprehensiveness of information, and 16.7% (IQR 8.3%-23.3%) for generic quality. While the comprehensiveness of information and generic quality received low scores, technical and functional aspects as well as readability resulted in higher scores (both Padjusted<.001). Regarding practice-specific variables, websites from private dental offices outside Germany (P=.04; B=-6.64, 95% CI -12.85 to -0.42) or from dentists who are a dental society member (P=.049; B=-3.55, 95% CI -7.09 to -0.01) resulted in lower readability scores (ie, were more difficult to read), while a shorter time since dentists' examination resulted in higher readability scores (P=.01; B=0.24 per year, 95% CI 0.05-0.43). The comprehensiveness of information from YouTube videos was 34.6% (IQR 13.5%-38.5%). However, the comprehensiveness of information did not vary between websites and YouTube videos (P=.09). Additionally, viewers' interaction (1.7%, IQR 0.7%-3.4%) and viewing rates (101%, IQR 54.6%-112.6%) were low.

CONCLUSIONS

The quality of German-language, patient-centered, web-based information on erosive tooth wear was limited. Especially, the comprehensiveness and trustworthiness of the available information were insufficient. Web-based information on erosive tooth wear requires improvement to inform patients comprehensively and reliably.

Oral health in patients with different sites of head and neck squamous cell carcinoma is not different

Oral health might not only act as risk factor for head and neck squamous cell carcinoma (HNSCC), but might also have a predictive value for the patients' survival. Currently, information on the effect of oral health on survival of patients with different sites of HNSCC is lacking. This single-center retrospective study aimed to compare oral health in patients with different sites of HNSCC and to analyse whether oral health is associated with survival in the different subsets of HNSCC patients. Dental records of HNSCC patients referred for dental assessment prior to radio(chemo)therapy were included. Patient-related parameters (age at time of diagnosis, sex, tobacco exposure, alcohol consumption, HPV status), treatment data (primary treatment, intent), performance status, tumor demographics (anatomical site, TNM staging), and oral health parameters (DMFT, periodontal health, teeth with/without root canal treatment and with/without periodontitis apicalis) were obtained. Oral health parameters were compared between different anatomical sites. Survival of all HNSCC patients and of individual subsets was assessed using Kaplan-Meier statistics, and the effect of tumor demographics, patient-related parameters, and oral health on survival was analysed by cox regression analyses (α = 5%). 371 patients with HNSCC (oral: n = 86, oropharyngeal: n = 174, hypopharyngeal: n = 59, laryngeal: n = 15, other: n = 37) were included. Oral health parameters did not differ between subsets (padj.≥0.199). Five-year cumulative survival of HNSCC patients amounted to 78.6%. Only for HNSCC originating in the oral cavity and oropharynx, survival was associated with the treatment intent (p = 0.015) or performance status (p = 0.007) in the multivariable analyses, respectively. Within the limitations of this study, oral health was not different between different subsets and had no significant effect on survival of HNSCC patients.

Teaching of posterior composites for the restoration of permanent teeth in undergraduate dental training programmes: Systematic review and meta-analysis

OBJECTIVES

To systematically assess aspects of teaching of posterior composite restorations (PCRs) in permanent teeth in dental schools.

STUDY SELECTION

Quantitative studies reporting on dental schools' teaching regarding the placement of PCRs in permanent teeth. Random-effects meta-analyses and meta-regressions were performed. Risk of bias was assessed based on the Medical Education Research Study Quality Instrument (MERSQI).

SOURCES

Electronic databases (MEDLINE via PubMed, EMBASE via Ovid, Web of Science, and Scopus) were searched in January 2023.

DATA

Forty sources reporting on 34 studies having surveyed 1,286 dental schools were included. Overall, 92.7% (95%-CI: 88.2-95.5) of dental schools reported to teach PCRs. PCRs in three-surface Class II cavities are taught by 82.0% (95%-CI: 70.4-89.7). The mandatory use of liners in deep cavities is taught by 78.3% (95%-CI: 68.9-85.5), and 44.0% (95%-CI: 34.3-54.2) reported to teach bulk-fill composites. While most posterior restorations placed by students were composites (56.1%; 95%-CI: 46.0-65.8), 94.7% (95%-CI: 86.6-98.0) of dental schools (still) teach posterior amalgam restorations. The proportion of dental schools teaching PCRs in three-surface Class II cavities increased and the mean proportion of PCRs among all posterior restorations increased over time (padj.≤0.003).

CONCLUSIONS

The teaching of PCRs in dental schools around the world reflects the increased use of resin composite in clinical practice, with students in countries where dental amalgam continues to be used, placing more posterior composites than restorations of dental amalgam. The teaching of PCRs, which is anticipated to increase, will continue to be refined with further developments in adhesive materials, devices, instrumentation, and techniques.

CLINICAL SIGNIFICANCE

Graduating dentists can be expected to be familiar with the use of resin composites for the restoration of posterior teeth.

In vitro study on the preventive effect of children's toothpastes on erosive tooth wear of primary bovine enamel and dentin

This in vitro study aimed to analyse the effect of various children's toothpastes on erosive tooth wear of primary bovine enamel and dentin. Enamel and dentin specimens (n = 12) were cyclically eroded (6 × 60 s/d, citric acid, pH 2.4) and brushed (2 × 15 s/d, 2 N) over 5 days. Nine fluoride toothpastes (500 to 1450 ppm) and eight toothpastes containing no fluoride or other active ingredients (hydroxyapatite and/or xylitol) were tested. Unbrushed specimens served as control. Tissue loss was quantified using widefield confocal microscopy and statistically analysed using two-way and one-way ANOVAs followed by Scheffe's (enamel) or Tamhane's (dentin) post-hoc tests (p < 0.05). Only one fluoride toothpaste (1400 ppm) was able to reduce erosive wear of enamel significantly by 15% compared to the control (p_adj. = 0.002). All fluoridated toothpastes reduced dentin surface loss significantly by 32 to 69% compared to the control (p_adj. ≤ 0.001), while fluoride-free toothpastes were unable to reduce dentin loss significantly (p_adj. ≥ 0.971). Most fluoridated toothpastes caused less erosive wear compared to fluoride-free toothpastes. Children toothpastes containing fluoride were more effective in reducing erosive wear compared to toothpastes containing no fluoride or other active ingredients.

Risk factors for and clinical presentations indicative of vertical root fracture in endodontically treated teeth - a systematic review and meta-analysis

INTRODUCTION

The aim of this study was to identify specific clinical signs or symptoms and potential risk factors which are most likely associated with the presence of a vertical root fracture (VRF) in endodontically treated teeth (ETT).

METHODS

Electronic databases (MEDLINE via PubMed, EMBASE via Ovid, Scopus, and Web of Science) were searched by two reviewers in October 2022 for clinical studies, in which at least either the clinical presentation or potential risk factors associated with a VRF were assessed. Risk of bias was assessed using the Newcastle-Ottawa scale. Meta-analyses of odds ratios (ORs) were performed separately for several signs or symptoms and risk factors.

RESULTS

Fourteen sources reporting on 2,875 teeth (489 with VRF and 2,388 without VRF) were included in the meta-analyses. Regarding the clinical presentation, the presence of sinus tracts (OR=4.87; 95%-CI: 1.58-15.0), increased periodontal probing depths (OR=13.24; 95%-CI: 5.44-32.22), swelling/abscess (OR=2.86; 95%-CI: 1.74-4.70), and tenderness to percussion (OR=1.74; 95% CI: 1.18-2.61) were significantly associated with the presence of a VRF (P_adj. value<.05). None of the assessed risk factors (sex, type of teeth, tooth location, posts, indirect restoration, apical extension of the root canal filling), were found to be significantly associated with the presence of a VRF (P_adj. value>.05).

CONCLUSIONS

Four clinical presentations were identified to be the most significant signs or symptoms for a VRF in ETT: presence of sinus tracts, increased probing depths, swelling/abscess, tenderness to percussion. None of the assessed risk factors pointed out to be significantly associated with a VRF.

REGISTRATION

CRD42022354108 (PROSPERO).

Implementation of repairs in dental practice: Randomized behavior simulation trial

BACKGROUND

Despite increasing evidence, dentists have not widely adopted repairs. The authors aimed to develop and test potential interventions targeting dentists' behavior.

METHODS

Problem-centered interviews were performed. Emerging themes were linked to the Behavior Change Wheel to develop potential interventions. The efficacy of 2 interventions was then tested in a postally delivered behavioral change simulation trial among German dentists (n = 1,472 per intervention). Dentists' stated repair behavior regarding 2 case vignettes was assessed. Statistical analysis was performed using McNemar test, Fisher exact test, and a generalized estimating equation model (P < .05).

RESULTS

Two interventions (guideline, treatment fee item) were developed on the basis of identified barriers. A total of 504 dentists participated in the trial (17.1% response rate). Both interventions significantly changed dentists' behavior toward repairs of composite and amalgam restorations, respectively (guideline: difference [Δ] = +7.8% and Δ = +17.6%, treatment fee item: Δ = +6.4% and Δ = +31.5%; adjusted P < .001). Dentists were more likely to consider repairs if they already performed repairs frequently (odds ratio [OR], 1.23; 95% CI, 1.14 to 1.34) or sometimes (OR, 1.08; 95% CI, 1.01 to 1.16), if they regarded repairs as highly successful (OR, 1.24; 95% CI, 1.04 to 1.48), if their patients preferred repairs over total replacements (OR, 1.12; 95% CI, 1.03 to 1.23), for partially defective composite restorations (OR, 1.46; 95% CI, 1.39 to 1.53), and after receiving 1 of the 2 behavioral interventions (OR, 1.15; 95% CI, 1.13 to 1.19).

CONCLUSIONS

Systematically developed interventions targeting dentists' repair behaviors are likely efficacious to promote repairs.

PRACTICAL IMPLICATIONS

Most partially defective restorations are replaced completely. Effective implementation strategies are required to change dentists' behavior. This trial was registered at https://www.

CLINICALTRIALS

gov. The registration number is NCT03279874 for the qualitative phase and NCT05335616 for the quantitative phase.

Scoring Single-Response Multiple-Choice Items: Scoping Review and Comparison of Different Scoring Methods

BACKGROUND

Single-choice items (eg, best-answer items, alternate-choice items, single true-false items) are 1 type of multiple-choice items and have been used in examinations for over 100 years. At the end of every examination, the examinees' responses have to be analyzed and scored to derive information about examinees' true knowledge.

OBJECTIVE

The aim of this paper is to compile scoring methods for individual single-choice items described in the literature. Furthermore, the metric expected chance score and the relation between examinees' true knowledge and expected scoring results (averaged percentage score) are analyzed. Besides, implications for potential pass marks to be used in examinations to test examinees for a predefined level of true knowledge are derived.

METHODS

Scoring methods for individual single-choice items were extracted from various databases (ERIC, PsycInfo, Embase via Ovid, MEDLINE via PubMed) in September 2020. Eligible sources reported on scoring methods for individual single-choice items in written examinations including but not limited to medical education. Separately for items with n=2 answer options (eg, alternate-choice items, single true-false items) and best-answer items with n=5 answer options (eg, Type A items) and for each identified scoring method, the metric expected chance score and the expected scoring results as a function of examinees' true knowledge using fictitious examinations with 100 single-choice items were calculated.

RESULTS

A total of 21 different scoring methods were identified from the 258 included sources, with varying consideration of correctly marked, omitted, and incorrectly marked items. Resulting credit varied between -3 and +1 credit points per item. For items with n=2 answer options, expected chance scores from random guessing ranged between -1 and +0.75 credit points. For items with n=5 answer options, expected chance scores ranged between -2.2 and +0.84 credit points. All scoring methods showed a linear relation between examinees' true knowledge and the expected scoring results. Depending on the scoring method used, examination results differed considerably: Expected scoring results from examinees with 50% true knowledge ranged between 0.0% (95% CI 0% to 0%) and 87.5% (95% CI 81.0% to 94.0%) for items with n=2 and between -60.0% (95% CI -60% to -60%) and 92.0% (95% CI 86.7% to 97.3%) for items with n=5.

CONCLUSIONS

In examinations with single-choice items, the scoring result is not always equivalent to examinees' true knowledge. When interpreting examination scores and setting pass marks, the number of answer options per item must usually be taken into account in addition to the scoring method used.

A Sex-Specific Evaluation of Dental Students' Ability to Perform Subgingival Debridement: Randomized Trial

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<.05).

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<.001).

CONCLUSIONS

Female and male students performed equally well in subgingival debridement. Therefore, sex-differentiated teaching methods are not necessary.

Relation Between Students' Theoretical Knowledge and Practical Skills in Endodontics: Retrospective Analysis

BACKGROUND

Dental undergraduate students are required to show sufficient practical skills prior to treating patients. Practical skills and the underlying theoretical knowledge are taught in preclinical courses. Usually, the learning outcome is assessed in written multiple-choice examinations (theoretical knowledge) and practical skills tests. However, students' assessment of practical skills is more time-consuming and prone to bias than objective multiple-choice examinations.

OBJECTIVE

This study aimed to analyze the relation between students' theoretical knowledge and practical skills in Endodontics. Furthermore, the predictive validity of theoretical knowledge assessment on students' practical skills was assessed.

METHODS

Examination results from all students who participated in the preclinical phantom course in Operative Dentistry (sixth semester of the undergraduate dental curriculum in Germany) between the summer-term 2015 and the summer-term 2022 were retrospectively evaluated (N=447). The effect of age, gender, previous course participation, and theoretical knowledge on students' practical skills was assessed using Pearson's correlations, Wilcoxon rank sum tests, and linear regression analysis. Subsequently, students' theoretical knowledge and practical skills were compared to identify a suitable pass-mark for students' theoretical knowledge associated with sufficient practical skills ≥60% (Fisher's exact test).

RESULTS

Students' theoretical knowledge was significantly associated with practical skills (P_adj.=.019, r=0.13). By using the current pass-mark for the theoretical knowledge of 60%, a significant differentiation between insufficient practical skills <60% and sufficient practical skills ≥60% was achieved (P=.024). However, for the discrimination between students with sufficient and insufficient practical skills, an adapted pass-mark for the theoretical knowledge would be more appropriate. The ideal pass-mark amounted to 58% (P=.020).

CONCLUSIONS

Students' practical skills and theoretical knowledge are significantly correlated. By objectively measuring students' theoretical knowledge, a rough estimation of students' practical skills (ie, a differentiation between sufficient and insufficient practical skills) is possible.

CLINICALTRIAL

Use of Multiple-Select Multiple-Choice Items in a Dental Undergraduate Curriculum: Retrospective Study Involving the Application of Different Scoring Methods

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<.05).

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; P<.001). Both the use of an inappropriate item type (34 items) and the presence of cues (30 items) impacted the scoring results. Inappropriately used Pick-N items resulted in lower mean raw scores (0.88 vs 0.93; P<.001), while inappropriately used MTF items resulted in higher mean raw scores (0.88 vs 0.85; P=.001). Mean raw scores were higher for MTF items with cues than for those without cues (0.91 vs 0.8; P<.001), while mean raw scores for Pick-N items with and without cues did not differ (0.89 vs 0.90; P=.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.

Survival analysis of fragment reattachments and direct composite restorations in permanent teeth after dental traumatic injuries

BACKGROUND/AIM

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.

MATERIAL AND METHODS

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).

RESULTS

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.

CONCLUSIONS

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.

Oral health in HPV-positive and HPV-negative patients with oropharyngeal squamous cell carcinoma

This study compared oral health in oropharyngeal squamous cell carcinoma (OPSCC) patients with positive or negative human papillomavirus (HPV) status and analysed whether oral health was associated with survival. Patients referred for dental assessment prior to radio(chemo)therapy between 2009 and 2019 were included. Patient-related risk factors for OPSCC (alcohol, tobacco, HPV status), age, sex, treatment (primary treatment, intent), performance status, tumor/node/metastasis (TNM) staging, and oral health parameters (DMFT, periodontal status, teeth with/without root canal treatment and with/without periodontitis apicalis) were compared between HPV-negative and HPV-positive patients. Survival was assessed using Kaplan-Meier statistics. The effect of patient-related risk factors and oral health parameters was analysed by cox regression analyses (α=5%). A total of 119 patients (n=50 HPV-negative, n=69 HPV-positive) was included. HPV-positive patients showed more present teeth, a higher number of filled teeth, were less often edentulous and presented a lower DMFT compared to HPV-negative patients (p_adj.≤0.003). Among dentulous patients, HPV-positive patients showed more present teeth and fewer teeth with periodontitis apicalis lacking a root canal treatment (p_adj.≤0.036). Survival probability differed between groups (p=0.006) and trended towards being associated with HPV status, tobacco exposure, performance status, T stage, N stage, and the number of missing or filled teeth as well as the number of root canal treated teeth with periodontitis apicalis and the number of teeth with periodontitis apicalis lacking a root canal treatment (p≤0.077). However, only tobacco exposure, performance status, and the number of teeth with periodontitis apicalis lacking a root canal treatment in dentulous patients remained significant in the multivariate analyses (p≤0.047). HPV-negative patients with OPSCC showed a poorer oral health compared to HPV-positive patients, but survival was not associated with oral health.

Micro-CT evaluation of frozen and embalmed human cadavers on the effect of root canal preparation on microcrack formation in old dentin

The aim of this study was to evaluate the existence of preoperative dentinal defects among differently preserved dentoalveolar bone-blocks (frozen vs. embalmed) and to investigate the effect of varying apical forces (low: <4 N, high: 4-8 N) during root canal preparation on microcrack formation using micro-computed tomography (micro-CT). Thirteen embalmed and seven frozen bone-blocks containing 1-3 single rooted teeth were collected. The teeth were evenly divided into three groups (n = 10): FLow (frozen, <4 N), ELow (embalmed, <4 N), EHigh (embalmed, 4-8 N). After working length determination all specimens were scanned preoperatively. Root canal preparation was performed using nickel-titanium instruments sizes 25/.06 and 40/.06 (F6 SkyTaper; Komet, Lemgo, Germany). A postoperative scan was performed and image stacks were co-registered. All cross-sectional images were screened to identify the presence of dentinal defects. The results were expressed as the percentage of teeth/slices presenting dentinal defects. The statistical analyses were performed with Kruskal-Wallis-Test and Mann-Whitney-U-Test (α = 5%). Embalmed specimens presented a significantly higher percentage of slices with preoperative microcracks (p<0.05) than frozen specimens. No significant difference between groups was observed regarding the induction of microcracks (p>0.05). Root canal preparation does not induce microcracks in dentoalveolar bone-blocks from donors of old age, irrespective of the preservation method and the apically directed forces.

Effect of face masks on salivary parameters and halitosis: Randomized controlled crossover trial

BACKGROUND

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.

METHODS

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).

RESULTS

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).

CONCLUSION

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.

CLINICAL TRIAL REGISTRATION

The protocol was prospectively registered at ClinicalTrials.gov (NCT04914208) on June 4, 2021.

Effect of Bioactive and Antimicrobial Nanoparticles on Properties and Applicability of Dental Adhesives

The aim of the study was to examine the applicability of bioactive and antibacterial nanoparticles to an experimental adhesive. The adhesive (60 wt% BisGMA, 15 wt% TEGDMA, 25 wt% HEMA) was mixed with combinations of 5 wt% methacryl-functionalized polyhedral oligomeric silsesquioxane (MA-POSS) and one kind of bioactive/antibacterial nanoparticles: 1 wt% core-shell silica-silver nanoparticle (SiO₂@Ag), 1 wt% bioactive glass with bismuth (BAG-Bi) or 1 wt% calcium phosphate (CAP). Pure adhesive served as control. The physicochemical (degree of conversion (DC), linear shrinkage (LS), shear and complex viscosity, water sorption (WS), sol fraction (SF)), biological (antimicrobial effect) and bioactive (mineral precipitation) properties were investigated. DC and LS remained unchanged. The combination of BAG-Bi/MA-POSS resulted in a significantly increased WS and SF compared to control. In addition, the combination of CAP/MA-POSS slightly increased the shear viscosity of the adhesive. The addition of the nanoparticles did not influence the antimicrobial effects compared to the pure adhesive. Improved mineral inducing capacity could be detected in all nanoparticle combinations. The combination of bioactive and/or antibacterial nanoparticles showed improved mineral inducing capacity, but no antibacterial properties. The material properties were not or only slightly affected.

Comparison of the Bleaching Efficacy of Different Agents Used for Internal Bleaching: A Systematic Review and Meta-Analysis

INTRODUCTION

The aim of this study 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, and Cochrane Library) were searched by 2 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 the Cochran Q test and I² statistic. Publication bias was evaluated using funnel plots.

RESULTS

Eight studies were included in the systematic review, 6 of which could be included in the meta-analyses. Internal bleaching led to a significant change in tooth shade (ΔSGU: 6.27 [95% confidence interval, 5.36-7.17], ΔE: 12.83 [95% confidence interval, 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 a better bleaching effect than sodium perborate (adjusted P value ≤ .026). Regarding ΔE, there were no significant differences between carbamide peroxide (37%), hydrogen peroxide (35%), and sodium perborate mixed with hydrogen peroxide (P = .051). The risk of bias of the 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 a comparison of bleaching agents and their concentrations, further studies with long-term recalls are necessary.

Adhesion to eroded enamel and dentin: systematic review and meta-analysis

OBJECTIVE

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 etch&rinse and self-etch adhesives and can be improved by surface pretreatment prior to bonding.

METHODS

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 (etch&rinse vs. self-etch) and aging (immediate vs. aged) was compared using subgroup analyses. Statistical heterogeneity was assessed using Cochran's Q and I²-statistic. Funnel plots and Egger's regression intercept tests were used to evaluate publication bias. Quality and risk of bias of included studies were also assessed.

RESULTS

Fourty-seven studies (45 in vitro, 2 in situ) were included in the systematic review and meta-analyses. Erosion impairs bond strength to dentin (p < 0.001; 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). Etch&rinse 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.

SIGNIFICANCE

Data from in vitro and in situ studies showed that erosion impairs dentin bonding of etch&rinse and self-etch adhesives and makes surface pretreatment prior to bonding of composite restorations necessary.

COVID-19 Pandemic: Effect of Different Face Masks on Self-Perceived Dry Mouth and Halitosis

Due to the COVID-19 pandemic, the use of face masks has increased, resulting in potential health-related side-effects. Therefore, the study aimed to analyse the effect of wearing face masks on self-perceived dry mouth and halitosis. A questionnaire addressing the daily wearing time of different face masks (community masks, surgical/medical masks and KN95-/N95-/FFP2-masks) and self-perceived dry mouth and halitosis was given to adults attending or working at a university hospital. Statistical analysis was performed using Wilcoxon signed-rank test and multiple linear regression analysis (p < 0.05). 3750 participants (age: 50.4 ± 15.5 years; 60.0% female) were included. During the pandemic, face masks were used for 4.7 ± 3.8 h per day: community masks: 0.9 ± 2.0 h, medical/surgical masks: 1.9 ± 2.8 h and KN95-/N95-/FFP2-masks: 1.9 ± 2.5 h per day. The use of face masks significantly increased self-perceived dry mouth and halitosis (both p < 0.001). Self-perceived dry mouth and halitosis increased with increasing wearing time (community masks: dry mouth: p < 0.001, halitosis: p = 0.014; medical/surgical masks: both: p < 0.001; KN95-/N95-/FFP2-masks: dry mouth: p < 0.001, halitosis: p = 0.011). The perception of dry mouth and halitosis was increased in females compared to males (both: p < 0.001). Participants used to wearing face masks prior to the pandemic perceived dry mouth to a higher extent (p = 0.043). Self-perceived halitosis was lower in older than in younger participants (p < 0.001). Due to the increased perception of dry mouth and halitosis, people might abstain from wearing face masks. Further studies need to analyse measurable changes in dry mouth or halitosis.

Survival of direct composite restorations placed under general anesthesia in adult patients with intellectual and/or physical disabilities

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.

Remote Teaching in a Preclinical Phantom Course in Operative Dentistry During the COVID-19 Pandemic: Observational Case Study

BACKGROUND

During the acute COVID-19 pandemic, physical access to the University Medical Center Göttingen was restricted for students. For the first time at our dental school, theoretical knowledge was imparted to students via asynchronous online screencasts and discussed via synchronous video meetings only.

OBJECTIVE

We aimed to assess the acceptance and effectiveness of distance education as a new teaching format for theoretical knowledge within the preclinical course in Operative Dentistry (sixth semester of the undergraduate dental curriculum in Germany).

METHODS

The phantom course comprised distance education (first phase, 11 weeks) and subsequent on-site practical demonstrations and training (second phase, 10 weeks). All theoretical knowledge was taught via online screencasts during distance education (except for the first week, 3 screencasts were uploaded per week resulting in a total of 30 screencasts). Until the end of the term, all students (N=33) were able to view the screencasts for an unlimited number of times. Theoretical knowledge was assessed in a summative examination after practical on-site teaching. Acceptance and effectiveness of the new curriculum and distance education were also measured based on an evaluation survey and students' self-perceived learning outcome, which was compared to the outcome from the two pre-COVID-19 terms.

RESULTS

Each screencast was viewed by a mean of 24 (SD 3.3) students and accessed a mean of 5.6 (SD 1.2) times per user (ie, by students who accessed the respective screencast at least once). During distance education, the number of accesses showed a linear trend over time. During the practical training phase, screencast views declined and increased again prior to the examination. Screencasts covering topics in Cariology, Restorative Dentistry, and Preventive Dentistry were viewed by more students than screencasts covering topics in Endodontology or Periodontology (both P=.047). Examination items in Periodontology showed inferior results compared to the other topics (P<.001). Within the different topics, students' self-perceived learning outcome did not differ from that during the pre-COVID-19 terms. Although most students agreed that the presented screencasts contributed to their learning outcome, pre-COVID-19 term students more strongly felt that lectures significantly contributed to their learning outcome (P=.03).

CONCLUSIONS

Screencasts showed high acceptance and effectiveness among the students but were not used as a learning tool by all students. However, students who viewed the screencasts accessed each screencast more frequently than they could have attended a conventional lecture. Screencast views were mostly due to intrinsic motivation.

Long-term treatment costs and cost-effectiveness of restoration repair versus replacement

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 (ICER_MEDIAN). Statistical analysis was performed using generalized linear mixed modeling (GLM), Chi²-test, and Wilcoxon rank-sum test (p < 0.05).

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 ICER_MEDIAN of replacement vs. repair was -146.8 Euro/% when extractions were considered as outcomes. Regarding major and any complications, mean ICER_MEDIAN 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.

Repair Surface Conditioning Measures Affect Enamel and Dentin Bond Strength

CLINICAL RELEVANCE

Contamination of enamel and dentin with repair surface conditioning measures should be avoided.

SUMMARY

Objectives: To analyze whether the contamination with different repair conditioning measures impairs the adhesive performance of a universal adhesive applied in etch-and-rinse mode (ER) or self-etch mode (SE).Methods and Materials: Bovine enamel and dentin surfaces (each subgroup n=16) were bonded with a universal adhesive in ER or SE after contamination with different repair conditioning measures (sandblasting, silica coating, hydrofluoric acid etching, self-etching ceramic primer). In half of the groups, sand-blasting, silica coating, and hydrofluoric acid etching was followed by the use of a universal primer. If the universal adhesive was applied in ER, contamination was performed either before or after phosphoric acid etching. If the universal adhesive was applied in SE, bonding was performed after contamination. In the control groups, no contamination was simulated. Shear bond strength (SBS) and failure modes of composite buildups were determined after thermal cycling (10,000 cycles, 5°C-55°C). Statistical analysis was performed using analyses of variance, Weibull statistics, and χ2 tests (p<0.05).Results: In ER, sandblasting and silica coating significantly reduced SBS (control: enamel =25.7±4.2 MPa; dentin = 22.0±5.3 MPa) only when performed after phosphoric acid etching. Contamination with hydrofluoric acid impaired SBS on enamel but not on dentin. The self-etching ceramic primer reduced SBS, but not significantly. The contamination with the universal primer had no significant effect. In SE, all repair conditioning measures except the universal primer reduced SBS (control: enamel = 20.3±5.5 MPa; dentin = 23.0±4.0 MPa).Conclusion: Contamination of enamel and dentin by repair conditioning measures potentially affects bond strength.

How to intervene in the caries process: proximal caries in adolescents and adults-a systematic review and meta-analysis

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.

Effectiveness of an innovative and interactive smoking cessation training module for dental students: A prospective study

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 < .001; d = 2.8) as well as in the OSCE (74.9% vs 44.7%; P < .001; d = 2.3) and also retained more knowledge (52.7% vs 36.5%; P < .001; d = 2.0) and skills (71.8% vs 47.6%; P < .001; d = 2.5) over a period of 6 months. Attitudes were similar across groups and time-points.

CONCLUSION

The teaching intervention equipped dental students with specific knowledge and skills required to effectively counsel smoking patients. Further research is required to assess the transfer of these skills to the clinical setting.

Quality of Information Regarding Repair Restorations on Dentist Websites: Systematic Search and Analysis

Background

Repairing instead of replacing partially defective dental restorations represents a minimally invasive treatment concept, and repairs are associated with advantages over complete restoration replacement. To participate in the shared decision-making process when facing partially defective restorations, patients need to be aware of the indications, limitations, and advantages or disadvantages of repairs. Patients are increasingly using the internet to gain health information like this online.

Objective

We aimed to assess the quality of German-speaking dentist websites on repairs of partially defective restorations.

Methods

Three electronic search engines were used to identify German-speaking websites of dental practices mentioning repairs. Regarding information on repairs, websites were assessed for (1) technical and functional aspects, (2) comprehensiveness of information, and (3) generic quality and risk of bias. Domains 1 and 3 were scored using validated tools (LIDA and DISCERN). Comprehensiveness was assessed using a criterion checklist related to evidence, advantages and disadvantages, restorations and defects suitable for repairs, and information regarding technical implementation. Generalized linear modeling was used to assess the impact of practice-specific parameters (practice location, practice setting, dental society membership, and year of examination or license to practice dentistry) on the quality of information. An overall quality score was calculated by averaging the quality scores of all three domains and used as primary outcome parameter. Quality scores of all three domains were also assessed individually and used as secondary outcomes.

Results

Fifty websites were included. The median score of quality of information was 23.2% (interquartile range [IQR] 21.7%-26.2%). Technical and functional aspects (55.2% [IQR 51.7%-58.6%]) showed significantly higher quality than comprehensiveness of information (8.3% [IQR 8.3%-16.7%]) and generic quality and risk of bias (3.6% [IQR 0.0%-7.1%]; P<.001/Wilcoxon). Quality scores were not related to practice-specific parameters (P>.05/generalized linear modeling).

Conclusions

The quality of German-speaking dentist websites on repairs was limited. Despite sufficient technical and functional quality, the provided information was neither comprehensive nor trustworthy. There is great need to improve the quality of information to fully and reliably inform patients, thereby allowing shared decision making.

Effectiveness of a universal adhesive for repair bonding to composite and amalgam

The study aimed to compare the repair bond strength of aged composite and amalgam repaired with resin composite after various mechanical and adhesive surface treatments. Specimens were aged by thermal cycling (10,000 cycles, 5-55°C) and randomly subjected to one of three surface treatments: diamond bur abrasion, aluminum oxide air abrasion, or silica coating. Conventional bonding or a universal adhesive with incorporated silane was applied afterward (each n = 16) and resin composite was attached. In the control groups (each n = 16), resin composite was attached using one of the above adhesives without prior mechanical surface conditioning. After further thermal cycling, the shear bond strength (SBS) and failure modes were assessed. Statistical analyses were performed using ANOVA, Weibull statistics, two sample t-tests, and Chi²-test (P < 0.05). The SBS of the repaired amalgam was significantly lower than that of the composite and mechanical pretreatment significantly increased SBS. The universal adhesive significantly improved the SBS of the repaired amalgam compared to the conventional bonding agent and mechanical pretreatment increased the number of cohesive/mixed failures. Amalgam restorations may be repaired using resin composites, but the resulting SBS is lower than that obtained with composite.

Erosion-Protective Capacity of the Salivary Pellicle of Female and Male Subjects Is Not Different

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.

Same, same, but different? A systematic review of protocols for restoration repair

OBJECTIVES

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.

DATA

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).

SOURCES

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.

STUDY SELECTION

(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).

CONCLUSIONS

The main treatment steps were consistently reported across repair protocols.

CLINICAL SIGNIFICANCE

Dentists may want to adopt widely recommended treatment steps when performing repairs of different restoration materials in their daily practice.

Questionnaire Survey on the Management of Erosive Tooth Wear

PURPOSE

This questionnaire survey aimed to analyse management strategies for erosive tooth wear and to identify factors influencing dentists' decision-making.

MATERIALS AND METHODS

A questionnaire presenting clinical cases with erosive tooth wear on anterior and posterior teeth (BEWE scores 1 to 3) was sent electronically to German dentists (n = 13.683). Statistical analysis was performed by Wilcoxon signed-rank tests, Kruskal-Wallis-tests and Fisher's exact tests (p <0.05).

RESULTS

Only 455 dentists (3.3%, mean age: 52.3 ± 9.6) participated. Suggested therapeutic measures were statistically significantly different between BEWE 1, 2 and 3 (p <0.001) and between anterior and posterior teeth with BEWE scores 1 or 2 (p ≤0.025). Initial erosive lesions (BEWE 1) were mainly treated by information about the main causes and/or preventive measures (posterior teeth: 75.6%, anterior teeth: 64.4%), only 20.0% and 31.3% considered restorative treatment for posterior and anterior teeth, respectively. For teeth presenting score 2, a very high proportion of dentists considered restorative treatment (posterior teeth: 60.6%) additionally to prevention, especially when anterior teeth (91.0%) were affected. In case of severe erosive lesions (BEWE 3), the vast majority of dentists considered restorative treatment (posterior teeth: 98.3%, anterior teeth: 99.8%). The decision-making was mainly dependent on the lesion depth, size of affected surfaces and the presence of pain. Fluoride agents and agents containing tin chloride or tin fluoride were most frequently recommended as preventive measures. If distinct defects (BEWE 2) were treated restoratively, mainly composite restorations were performed (posterior teeth: 72.0%, anterior teeth: 90.5%). Severe defects (BEWE 3) were mostly restored with ceramic restorations (posterior teeth: 66.1%, anterior teeth: 66.6%).

CONCLUSION

Stepwise management of erosive tooth wear was observed. Dentists' decision-making was related to severity and localisation of erosive tooth wear and to various patient-related factors (e.g. depth of lesion and size of affected surface per tooth).

Effect of different scoring approaches upon credit assignment when using Multiple True-False items in dental undergraduate examinations

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 Göttingen 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 < .05).

RESULTS

Average scoring results per item highly differed between the scoring approaches and ranged from 0.46 (MR) to 0.92 (Dichotomized MTF). Presence of cues leads to significantly higher scoring in case of all scoring approaches (P < .001; +0.14 on average). However, effect of cues differed amongst scoring approaches and ranged from +0.04 (Dichotomized MTF) to +0.20 (MR).

CONCLUSION

Scoring of MTF items is complex. The data presented in this manuscript may help educators make informed choices about scoring algorithms.

Dental Students' Factual and Procedural Knowledge Retention in Operative Dentistry in a Clinical Dental Curriculum

The aim of this study was to evaluate dental students' retention of factual and procedural knowledge gained in a preclinical course in operative dentistry during a clinical dental curriculum. In 2017, all 157 seventh- to tenth-semester dental students at a dental school in Germany were asked to repeat the same written examination performed at the end of the preclinical course in the sixth semester. The examinations consisted of 30 multiple-choice questions covering factual and procedural knowledge. The percentage of correctly answered questions per exam and differences in correct answers between the original examination and the re-examination (per question) were analyzed. Students were also asked to self-rate their percentage of correctly answered questions and their knowledge in various disciplines of operative dentistry at the times of the original examination and the re-examination. After exclusions, data were analyzed for 129 students, for a participation rate of 82%. For the seventh- and tenth-semester students, the results on the original examination and the re-examination were not significantly different, while the eighth- and ninth-semester students performed significantly better on the original examination than the re-examination. In all semesters, procedural knowledge remained stable between the original examination and the re-examination, while factual knowledge decreased slightly. Their performance on the original examination was underestimated by the eighth- and ninth-semester students. All the students underestimated their performance on the re-examination. Students mostly rated their knowledge level significantly higher on the original examination than on the re-examination. Overall, this study found that factual and procedural knowledge gained in a preclinical course in operative dentistry was not increased during the clinical dental curriculum.

Understanding the management and teaching of dental restoration repair: Systematic review and meta-analysis of surveys

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.

Etiology and pathogenesis of dental erosion

The condition of dental erosion is defined as acid-related loss of tooth structure which does not involve microorganisms. Depending on the origin of the acid, extrinsic (usually caused by acids in food) and intrinsic (caused by endogenous acid) erosion can be distinguished. The presence and severity of erosive defects depend on various parameters such as nutrition, saliva, general diseases, and mechanical stress by abrasion and attrition. As an example, dietary habits which involve frequent intake of acidic food and beverages, occupational acid exposure, as well as certain drugs or diseases that affect saliva flow rate are accompanied by an increased risk of erosive dental hard tissue defects. By a thorough clinical examination and an accurate anamnesis, various erosion-related risk factors can be identified and strategies to reduce or eliminate these factors be identified.

Repair restorations: Questionnaire survey among dentists in the Canton of Zurich, Switzerland

The aim of this study was to carry out a representative survey on the implementation of and experience with repairs of single-tooth restorations among dentists in the Canton of Zurich, Switzerland. An anonymous questionnaire was sent to all 1,411 dentists registered in the Canton of Zurich; 38.9% of the delivered questionnaires were returned and 35.3% could be evaluated. The statistical analysis comprised Kendall’s rank correlation coefficient (tau), Wilcoxon signed-rank tests, and Kruskal-Wallis tests. The level of significance was set at p≤0.05. Repair restorations are frequently made (composite: 98.5%, ceramic: 88.9%, crowns: 86.5%, metal: 54.6%, amalgam: 51.5%). Main indications for repairs were the partial loss of an existing restoration or of the adjacent dental hard substance, while restoration failures due to secondary caries were repaired to a lesser extent. The decision to repair is largely dependent on the size of the defect (90%), the size of the original restoration (63%), and the material of the failed restoration (84%). Repair restorations are most frequently made with composite following adequate conditioning of the repair surface. A majority of the dentists rate the lifespan of repair restorations as reduced in comparison with newly made restorations. In summary, repairs of defective single-tooth restorations are frequently performed by dentists in the Canton of Zurich, Switzerland, and constitute a well-established treatment procedure.

Graft-derived cell-free DNA, a noninvasive early rejection and graft damage marker in liver transplantation: A prospective, observational, multicenter cohort study

BACKGROUND

Graft-derived cell-free DNA (GcfDNA), which is released into the blood stream by necrotic and apoptotic cells, is a promising noninvasive organ integrity biomarker. In liver transplantation (LTx), neither conventional liver function tests (LTFs) nor immunosuppressive drug monitoring are very effective for rejection monitoring. We therefore hypothesized that the quantitative measurement of donor-derived cell-free DNA (cfDNA) would have independent value for the assessment of graft integrity, including damage from acute rejection.

METHODS AND FINDINGS

Traditional LFTs were performed and plasma GcfDNA was monitored in 115 adults post-LTx at three German transplant centers as part of a prospective, observational, multicenter cohort trial. GcfDNA percentage (graft cfDNA/total cfDNA) was measured using droplet digital PCR (ddPCR), based on a limited number of predefined single nucleotide polymorphisms, enabling same-day turn-around. The same method was used to quantify blood microchimerism. GcfDNA was increased >50% on day 1 post-LTx, presumably from ischemia/reperfusion damage, but rapidly declined in patients without graft injury within 7 to 10 d to a median <10%, where it remained for the 1-y observation period. Of 115 patients, 107 provided samples that met preestablished criteria. In 31 samples taken from 17 patients during biopsy-proven acute rejection episodes, the percentage of GcfDNA was elevated substantially (median 29.6%, 95% CI 23.6%-41.0%) compared with that in 282 samples from 88 patients during stable periods (median 3.3%, 95% CI 2.9%-3.7%; p < 0.001). Only slightly higher values (median 5.9%, 95% CI 4.4%-10.3%) were found in 68 samples from 17 hepatitis C virus (HCV)-positive, rejection-free patients. LFTs had low overall correlations (r = 0.28-0.62) with GcfDNA and showed greater overlap between patient subgroups, especially between acute rejection and HCV+ patients. Multivariable logistic regression modeling demonstrated that GcfDNA provided additional LFT-independent information on graft integrity. Diagnostic sensitivity and specificity were 90.3% (95% CI 74.2%-98.0%) and 92.9% (95% CI 89.3%-95.6%), respectively, for GcfDNA at a threshold value of 10%. The area under the receiver operator characteristic curve was higher for GcfDNA (97.1%, 95% CI 93.4%-100%) than for same-day conventional LFTs (AST: 95.7%; ALT: 95.2%; γ-GT: 94.5%; bilirubin: 82.6%). An evaluation of microchimerism revealed that the maximum donor DNA in circulating white blood cells was only 0.068%. GcfDNA percentage can be influenced by major changes in host cfDNA (e.g., due to leukopenia or leukocytosis). One limitation of our study is that exact time-matched GcfDNA and LFT samples were not available for all patient visits.

CONCLUSIONS

In this study, determination of GcfDNA in plasma by ddPCR allowed for earlier and more sensitive discrimination of acute rejection in LTx patients as compared with conventional LFTs. Potential blood microchimerism was quantitatively low and had no significant influence on GcfDNA value. Further research, which should ideally include protocol biopsies, will be needed to establish the practical value of GcfDNA measurements in the management of LTx patients.

Digital droplet PCR for rapid quantification of donor DNA in the circulation of transplant recipients as a potential universal biomarker of graft injury

BACKGROUND

Cell-free DNA (cfDNA) from grafts in the circulation of transplant recipients is a potential biomarker of rejection. Its usefulness was investigated after heart transplantation during the maintenance phase by use of microarrays and massive parallel sequencing of donor and recipient DNA. Disadvantages of these methods are high costs, long turnaround times, and need for donor DNA. Therefore, we sought to develop a rapid and cost-effective method using digital droplet PCR (ddPCR).

METHODS

Plasma samples were collected from stable recipients after liver (LTx, n = 10), kidney (KTx, n = 9), and heart (HTx, n = 8) transplantation as well as from 7 additional patients directly after LTx. Known single-nucleotide polymorphisms were selected for high minor allelic frequencies, of which 41 hydrolysis probe assays were established. Plasma cfDNA was preamplified, followed by conventional real-time PCR to define informative (heterologous) SNPs, which were then used for quantification (percentage) of graft-derived cfDNA (GcfDNA) using ddPCR.

RESULTS

Mean recovery was 94% (SD, 13%) with an imprecision of 4%-14% with the use of controls with 2% minor allele. GcfDNA in stable patients was <6.8% (LTx), <2.5% (KTx), and <3.4% (HTx). On the day of LTx, GcfDNA was approximately 90% and by day 10 it was <15% in complication-free LTx recipients. In 2 patients with biopsy-proven rejection, GcfDNA increased to >60%, whereas in 1 patient with cholestasis no increase was found.

CONCLUSIONS

A novel, cost-effective, rapid technique was developed to quantify GcfDNA in transplant recipients. This technique embodies a promising, potentially universal biomarker for early detection of rejection, which could enable more effective therapeutic interventions.