"Karius and Baktus": A Critical Appraisal of Enger's Seminal Storybook.

Karius and Baktus, first published in 1949, is one of the most influential storybooks with dental caries as main theme and it remains in wide use for domestic health education. This study aimed at assessing oral health related contents of the historic storybook in the light of the current body of cariologic evidence. Two investigators independently identified phrases in the storybook with cariologically relevant content. Dental health related contents were systematically evaluated with respect to the current body of cariologic evidence. Karius and Baktus highlights important etiopathogenetic and preventive aspects such as sugars consumption and tooth brushing with toothpaste. Its behavior management techniques and narrative health didactics concerning dental care for children are, however, outmoded. The cariologic core statements in Karius and Baktus have remained valid whereas certain narrative features may have some drawbacks when employing the historic storybook for educational purposes for young children.

Accuracy of a separating foil impression using a novel polyolefin foil compared to a custom tray and a stock tray technique.

PURPOSE: To compare the dimensional accuracy of three impression techniques- a separating foil impression, a custom tray impression, and a stock tray impression. MATERIALS AND METHODS: A machined mandibular complete-arch metal model with special modifications served as a master cast. Three different impression techniques (n = 6 in each group) were performed with addition-cured silicon materials: i) putty-wash technique with a prefabricated metal tray (MET) using putty and regular body, ii) single-phase impression with custom tray (CUS) using regular body material, and iii) two-stage technique with stock metal tray (SEP) using putty with a separating foil and regular body material. All impressions were poured with epoxy resin. Six different distances (four intra-abutment and two inter-abutment distances) were gauged on the metal master model and on the casts with a microscope in combination with calibrated measuring software. The differences of the evaluated distances between the reference and the three test groups were calculated and expressed as mean (± SD). Additionally, the 95% confidence intervals were calculated and significant differences between the experimental groups were assumed when confidence intervals did not overlap. RESULTS: Dimensional changes compared to reference values varied between -74.01 and 32.57 µm (MET), -78.86 and 30.84 (CUS), and between -92.20 and 30.98 (SEP). For the intra-abutment distances, no significant differences among the experimental groups were detected. CUS showed a significantly higher dimensional accuracy for the inter-abutment distances with -0.02 and -0.08 percentage deviation compared to MET and SEP. CONCLUSION: The separation foil technique is a simple alternative to the custom tray technique for single tooth restorations, while limitations may exist for extended restorations with multiple abutment teeth.

Partial Ceramic Crowns Prepared by Dental Students: Clinical Performance Up to Five Years.

Partial ceramic crowns (PCCs) are an accepted treatment option for the restoration of posterior teeth with deficient tooth substance. Data on the survival of PCCs fabricated by dental students are scarce. The aim of this retrospective clinical study was to investigate the clinical performance and longevity of PCCs placed by dental students in the last year of their training program at the University of Basel, Switzerland. Eighty-eight patients who had received at least one PCC (n=108) in the program were considered for clinical assessment; their records were analyzed to detect previous complications or failures; and they were contacted by telephone. Criteria regarding aesthetic, functional, and biological aspects were rated with a scoring system from 1=clinically excellent to 5=clinically poor. The response rate was 66.3% (55 of 83 included patients), and 72.2% (n=78) of the PCCs were included in the analysis. Five PCCs had been lost within ten to 78 months after treatment. Six PCCs were recorded as failures (score 5), and ten received clinically unsatisfactory gradings (score 4). The risk of a clinically poor outcome was 14% after five years (86% survival), while the overall success rate was 63.5%. These results suggest that the clinical procedure of PCCs was successfully implemented by these students with satisfactory clinical survival.

Evaluation of a New Grading System for Clinical Skills in Dental Student Clinics.

Several evaluation systems for clinical exams have been suggested over the years, but no systematic analysis of checklists or criteria-based exam forms has yet been undertaken. The aims of this study were to analyze criteria-based evaluation forms and to identify areas in the teaching process potentially requiring improvements. All evaluation forms introduced in 2012 at the Clinic for Periodontology, Endodontology, and Cariology at the University Center of Dental Medicine in Basel, Switzerland, and applied over a three-year period (n=1,093 in 2015) were analyzed using predefined criteria. The authors investigated how well clinical tasks were examined with the given criteria and which criteria were preferably evaluated with a grading system (0-2) or a yes/no choice. The average final grades ranged from 0.89 (n=92) for gold inlay preparation to 1.76 (n=46) for periodontal treatment. Comments were made in 38.5% (n=356) of all exams, mainly highlighting specific aspects of existing criteria. Overall, 13 criteria out of 66 should be checked instead of graded. This methodological analysis of exam forms assessing tasks in operative dentistry yielded valuable information on areas with potential for improvement in the dental curriculum and the evaluation process. Aspects that require more theoretical background and/or hands-on recommendations from experienced clinicians were identified, and ways of further refining and redesigning the evaluation forms were proposed.

Do periapical and periodontal pathologies affect Schneiderian membrane appearance? Systematic review of studies using cone-beam computed tomography.

OBJECTIVES: This systematic review analyzed the relationship between periapical and periodontal pathologies in the posterior maxilla and the appearance of the Schneiderian membrane in cone-beam computed tomography (CBCT) compared with sound dentitions. METHODS: Five electronic databases (Cochrane Library, Embase, OpenGrey, PubMed, Web of Science), complemented by hand searching, were screened up to May 9, 2016. Human clinical studies that used CBCT and contained information on the periapical/periodontal status in the posterior maxilla and Schneiderian membrane appearance were included. A weighted vote counting (WVC) method was applied to summarize results across studies. RESULTS: Out of 413 records, 20 studies were included. In the WVC, the studies that observed a positive association between periapical lesions and the appearance of the Schneiderian membrane outweighed those that found no such association (WVC 51 % and WVC 33 %, respectively), with some studies yielding indeterminate results (WVC 16 %). Regarding the relation between periodontal pathologies and the appearance of the Schneiderian membrane, WVC produced a tie between studies demonstrating a positive association (WVC 46 %) and those showing no association (WVC 44 %); one study (WVC 10 %) reported indeterminate results. CONCLUSIONS: On CBCT scans, periapical lesions in the posterior maxilla are likely to be associated with Schneiderian membrane thickening. In contrast, current evidence regarding the relation between periodontal diseases and the appearance of the Schneiderian membrane in CBCT is inconclusive. CLINICAL RELEVANCE: Incidental maxillary sinus findings on CBCT scans warrant thorough differential diagnosis. Frequently, they may be related to dental pathologies.

Evaluation of the dental curriculum at the University of Basel. Does the Master of Dental Medicine adequately prepare for the professional practice?

The present study reports the results of a structured survey of graduates intending to evaluate the education at the Dental School of the University of Basel in the years from 2006 to 2014. In addition, dentists and practice owners supervising graduates from Basel in daily clinical routine or hiring them as assistant dentists were questioned. The aims of the current survey were (1) to analyze own subjective experiences, (2) to assess potential differences between the cohorts prior to and after the implementation of the Bologna reform, (3) to compare the rating regarding theoretical knowledge and practical skills, and (4) to disclose potential for improvement. It was found that according to both their own assessment and the rating of the practice owners, graduates possess the basic dental expertise. The alumni rated their theoretical knowledge higher than their clinical practical skills and indicated a potential for intensification in the fields of dental surgery and implantology. When comparing the cohorts who had completed their studies according to the old (until 2010) and new study regulations, there were only minor differences; the own skills related to patient information about treatments were better rated by alumni who had been trained according to the new study regulations. The curriculum leading to the Master of Dental Medicine at the University of Basel fundamentally prepares graduates for the professional activity, but the additional acquisition of clinical experience in daily practice is indispensable.

Resin-bonded restorations: a strategy for managing anterior tooth loss in adolescence.

In children or adolescents with anterior tooth loss, space closure with the patient's own teeth should be considered as the first choice to avoid lifelong restorative needs. Thorough diagnostics and treatment planning are required when autotransplantation or orthodontic space closure is considered. If these options are not indicated and a single tooth implant restoration is considered, implant placement should be postponed until adulthood, particularly in young women and in patients with hyperdivergent skeletal growth pattern. A ceramic resin-bonded fixed dental prosthesis with 1 retainer is an excellent treatment solution for the interim period; it may also serve as a long-term restoration, providing that sound enamel structure is present, sufficient framework dimensions have been provided, adhesive cementation techniques have been meticulously applied, and functional contacts of the cantilever pontic avoided. In contrast, a resin-bonded fixed dental prosthesis with a metal framework and retentive preparation is indicated if the palatal enamel structure is compromised, interocclusal clearance is limited, splinting (such as after orthodontic treatment) is required, or more than 1 tooth has to be replaced.

Influence of proximal box elevation on the marginal quality and fracture behavior of root-filled molars restored with CAD/CAM ceramic or composite onlays.

OBJECTIVES: This study investigated the influence of proximal box elevation (PBE) with composite resin when applied to deep proximal defects in root-filled molars with mesio-occluso-distal (MOD) cavities, which were subsequently restored with computer-aided designed/computer-aided manufacturing (CAD/CAM) ceramic or composite restorations. MATERIALS AND METHOD: Root canal treatment was performed on 48 human mandibular molars. Standardized MOD cavities were prepared with the distal box located 2 mm below the cemento-enamel junction (CEJ). The teeth were randomly assigned to one of four experimental groups (n = 12). In groups G1 and G2, the distal proximal box was elevated up to the level of the CEJ with composite resin (PBE). No elevation was performed in the remaining two groups (G3, G4). CAD/CAM restorations were fabricated with feldspathic ceramic (Vita Mark II, CER) in groups G1 (PBE-CER) and G3 (CER) or with resin nano-ceramic blocks (Lava Ultimate, LAV) in groups G2 (PBE-LAV) and G4 (LAV). Replicas were taken before and after thermomechanical loading (TML; 1.2 Mio cycles; 49 N; 3,000 thermocycles between 50 °C and 5 °C). Following TML, load was applied until failure. Fracture analysis was performed under a stereomicroscope (×16). Marginal quality before and after TML (tooth restoration, composite restoration) was evaluated using scanning electron microscopy (×200). RESULTS: After TML, lower percentages of continuous margins were observed in groups G1-G3 compared with pre-TML assessments; however, the differences were not statistically significant. For group G4-LAV, the marginal quality after TML was significantly better than in any other group. The highest mean fracture value was recorded for group G4. No significant difference was found for this value between the groups with PBE compared with the groups without PBE, regardless of the material used. The specimens restored with ceramic onlays exhibited fractures that were mainly restricted to the restoration while, in teeth restored with composite onlays, the percentage of catastrophic failures (fractures beyond bone level) was increased. CONCLUSION: PBE had no impact on either the marginal integrity or the fracture behavior of root canal-treated mandibular molars restored with feldspathic ceramic onlays. CAD/CAM-fabricated composite onlays were more favorable than ceramic onlays in terms of both marginal quality and fracture resistance, particularly in specimens without PBE. CLINICAL RELEVANCE: Composite onlays with or without PBE may be a viable approach for the restoration of root-filled molars with subgingival MOD cavities.

Analysis of the effects of air polishing powders containing sodium bicarbonate and glycine on human teeth.

OBJECTIVES: The aim of this study was an analysis of the root surface roughness caused by air polishing powders containing sodium bicarbonate or glycine. METHODS: The roots of human molars were sectioned into dentin discs and irradiated with three different powders: (A) sodium bicarbonate (dv50 = 62 µm), (B) glycine (dv50 = 49 µm) and (C) glycine (dv50 = 21 µm). Standardized conditions in terms of instrumentation time (5 and 10 s), pressure (1.8 bar), distance (2 and 5 mm) and angulation (45° and 90°) were applied. Surface roughness (DIN EN ISO 4287:1998) of the probes was analysed by means of the surface profile values "Pa" and "Pt" and the surface roughness value "Rz". The effect of treatment (treated vs. untreated) was studied on each disc. Geometric mean ratios (GMRs) from mixed effects models and confidence intervals (95% CI) were calculated. RESULTS: For Pa, the comparison revealed significant differences between powders A and B (GMR 3.57, 95 % CI 2.87-4.43, p < 0.001) and powders A and C (GMR 2.72, 95% CI 2.20-3.37, p < 0.001) for the overall effects. With respect to Pt, significant differences occurred between powders A and B (GMR 2.49, 95% CI 2.11-2.94, p < 0.001) and powders A and C (GMR 2.39, 95% CI 2.03-2.82, p < 0.001). Between powders B and C, there were no significant differences for Pa, Rz and Pt. CONCLUSION: Air polishing powders containing glycine caused significantly less alterations on human root surfaces compared to powders containing sodium bicarbonate. CLINICAL SIGNIFICANCE: Powders containing glycine caused a significantly lower increase in root surface roughness compared to those containing sodium bicarbonate. Powders containing sodium bicarbonate may not be indicated for root surface treatment.