Effectiveness of a manual test at the beginning of dental school

INTRODUCTION

This study analysed whether the SAZAMED (Self-assessment for dentistry studies) manual test conducted as an exercise or examination in the first year of dental studies, and the official aptitude test for medical studies (EMS), can predict future performance of dental students.

MATERIALS AND METHODS

Students enrolled in the dental curriculum at the University of Basel between 2009/10 and 2019/20 were categorized: Group A conducted the SAZAMED in the third bachelor year (BA) and second master year (MA), group B practiced in the first and third BA and second MA and group C had to pass the test in the first BA with repetition in the third BA and second MA. SAZAMED comprised (i) wire bending, (ii) modelling sphere and cube, (iii) drawing mirror-inverted and (iv) indirect drawing over a mirror. Comparative variables were the EMS per cent rank and test scores in practical-clinical examinations in the third BA and the second MA.

RESULTS

Data were available from 329 students over the 10-year period. Repeaters and dropouts had poorer performance in the first BA SAZAMED than students who did not (p < 0.001). Among the four SAZAMED exercises, mirror-inverted drawing was the strongest predictor of future student performance. The official aptitude test EMS correlated with the third BA certificate (p = 0.012), but failed to predict repeaters and dropouts.

CONCLUSION

Since academic success was associated with significantly better scores on the first BA SAZAMED, it is considered a predictor and recommended in addition to the official EMS to identify students in need of intervention programmes or who should choose a different field of study.

Biosymbiotic platform for chronic long-range monitoring of biosignals in limited resource settings

Remote patient monitoring is a critical component of digital medicine, and the COVID-19 pandemic has further highlighted its importance. Wearable sensors aimed at noninvasive extraction and transmission of high-fidelity physiological data provide an avenue toward at-home diagnostics and therapeutics; however, the infrastructure requirements for such devices limit their use to areas with well-established connectivity. This accentuates the socioeconomic and geopolitical gap in digital health technology and points toward a need to provide access in areas that have limited resources. Low-power wide area network (LPWAN) protocols, such as LoRa, may provide an avenue toward connectivity in these settings; however, there has been limited work on realizing wearable devices with this functionality because of power and electromagnetic constraints. In this work, we introduce wearables with electromagnetic, electronic, and mechanical features provided by a biosymbiotic platform to realize high-fidelity biosignals transmission of 15 miles without the need for satellite infrastructure. The platform implements wireless power transfer for interaction-free recharging, enabling long-term and uninterrupted use over weeks without the need for the user to interact with the devices. This work presents demonstration of a continuously wearable device with this long-range capability that has the potential to serve resource-constrained and remote areas, providing equitable access to digital health.

Accuracy of Selective Enamel Etching: A Computer-assisted Imaging Analysis

OBJECTIVE

To assess the accuracy of selective enamel etching (SEE) in a laboratory setup simulating clinical conditions.

METHODS AND MATERIALS

A model with permanent human teeth was fabricated. It included a first mandibular molar with a mesio-occlusal-distal inlay preparation, a maxillary central incisor, and a canine with a class IV and class V cavity, respectively. Two dentists (with 1 year and 10 years work experience) repeatedly (n=10 per cavity) performed SEE with a custom gel that had identical rheological properties as a commercially available phosphoric acid etchant. An intraoral scanner was used for image acquisition. To assess the accuracy of SEE, special software was used (OraCheck, Cyfex, Zurich, Switzerland). Two independent investigators analyzed baseline scans and scans taken of the cavities while the gel was in place. The statistical analysis comprised t-tests, Pearson correlation, and analysis of variance (α=0.05).

RESULTS

The level of accuracy, whose average values ranged from 61.1% to 87.0%, showed significant differences between teeth, with the highest level observed in the class V cavity, followed by the class II inlay preparation and the class IV cavity (p<0.001). Across the cavities, no significant correlation was observed between the application time and the accuracy of SEE (p=0.07).

CONCLUSION

This laboratory study suggests that inadvertent conditioning of dentin adjacent to enamel may be common during SEE. Investigations involving larger samples of dentists are needed to corroborate this finding.

Quality of CAD-CAM inlays placed on aged resin-based composite restorations used as deep margin elevation: a laboratory study

OBJECTIVES

To assess the impact of the age of resin-based composite (RBC) restorations used for deep margin elevation (DME) on the marginal quality and fracture resistance of inlays.

MATERIALS AND METHODS

Permanent human molars with direct RBC restorations, involving the mesial, occlusal, and distal surface (MOD), were allocated to four groups (each n = 12). Half of the teeth underwent thermomechanical loading including 240,000 occlusal load cycles and 534 thermal cycles (TML, 5 °C/55 °C; 49 N, 1.7 Hz). With RBC left in one proximal box as DME, all teeth received MOD inlays, made from lithium disilicate (LDS) or a polymer-infiltrated ceramic network material (PICN). The restored teeth underwent TML including 1.2 million occlusal cyclic loadings and 2673 thermal cycles. The marginal quality was assessed at baseline and after both runs of TML. Load-to-fracture tests were performed. The statistical analysis comprised multiple linear regressions (α = 0.05).

RESULTS

Simulated aging of RBC restorations had no significant effect on the marginal quality at the interface between the RBC and the tooth and the RBC and the inlay (p ≥ 0.247). Across time points, higher percentages of non-continuous margin were observed between the inlay and the tooth than between the tooth and the RBC (p ≤ 0.039). The age of the DME did not significantly affect the fracture resistance (p ≥ 0.052).

CONCLUSIONS

Artificial aging of RBC restorations used for DME had no detrimental effect on the marginal quality and fracture resistance of LDS and PICN inlays.

CLINICAL RELEVANCE

This laboratory study suggests that-in select cases-intact, direct RBC restorations not placed immediately before the delivery of an indirect restoration may be used for DME.

RoBDEMAT: A risk of bias tool and guideline to support reporting of pre-clinical dental materials research and assessment of systematic reviews

OBJECTIVES

To develop a risk of bias tool for pre-clinical dental materials research studies that aims to support reporting of future investigations and improve assessment in systematic reviews.

METHODS

A four-stage process following EQUATOR network recommendations was followed, which included project launch, literature review, Delphi process and the tool finalization. With the support of the European Federation of Conservative Dentistry (EFCD) and the Dental Materials Group of the International Association for Dental Research (DMG-IADR), a total of 26 expert stakeholders were included in the development and Delphi vote of the initial proposal. The proposal was built using data gathered from the literature review stage. During this stage, recent systematic reviews featuring dental materials research, and risk of bias tools found in the literature were comprehensively scanned for bias sources. The experts thus reached a consensus for the items, domains and judgement related to the tool, allowing a detailed guide for each item and corresponding signalling questions.

RESULTS

The tool features nine items in total, spread between 4 domains, pertaining to the following types of bias: bias related to planning and allocation (D1), specimen preparation (D2), outcome assessment (D3) and data treatment and outcome reporting (D4). RoBDEMAT, as presented, features signalling questions and a guide that can be used for RoB judgement. Its use as a checklist is preferred over a final summary score.

CONCLUSION

RoBDEMAT is the first risk of bias tool for pre-clinical dental materials research, supported and developed by a broad group of expert stakeholders in the field, validating its future use.

CLINICAL SIGNIFICANCE

This new tool will contribute the study field by improving the scientific quality and rigour of dental materials research studies and their systematic reviews. Such studies are the foundation and support of future clinical research and evidence-based decisions.

Effect of repeated ultrasonic instrumentation on single-unit crowns: a laboratory study

OBJECTIVES

This laboratory study aimed to assess the effects of ultrasonic instrumentation, simulating 10 years of supportive periodontal therapy (SPT), on single-unit crowns.

MATERIALS AND METHODS

Standardized crowns were fabricated from porcelain-fused-to-metal (PFM) (n = 12), zirconia (ZrO₂) (n = 12), lithium disilicate (LDS) (n = 12), feldspar ceramic (FSFC) (n = 6), and polymer-infiltrated ceramic network material (PICN) (n = 6). The crowns, luted on PICN abutments with resin-based luting material (RBLM), and if applicable glass ionomer cement (GILC), underwent thermal cycling and trimonthly ultrasonic instrumentation. After 1 and 10 years of simulated SPT, restoration quality assessments were performed, comprising profilometric surface roughness measurements, marginal integrity evaluations, and scores for luting material remnants and visible cracks. The statistical analysis included multiple logistic regressions with nested designs (α = 0.05).

RESULTS

During simulated SPT, bulk fractures (n = 2) and a de-cementation failure (n = 1) of LDS and ZrO₂ crowns were observed. No significant change in roughness was detected after 10 years (p = 0.078). Over time, marginal defects increased (p = 0.010), with PFM crowns showing the highest rate of chippings at sites with a narrow shoulder. Fewer marginal defects were detectable on crowns luted with RBLM compared with GILC (p = 0.005). Luting material remnants decreased during SPT (p < 0.001). Ultrasonic instrumentation caused cracks in most crown materials, in particular at sites with a narrow shoulder and in PFM crowns.

CONCLUSIONS

Repeated ultrasonic instrumentation may damage single-unit crowns. PFM crowns with a narrow, all-ceramic margin are especially prone to defects.

CLINICAL RELEVANCE

Frequent ultrasonic instrumentation of restoration margins of fixed dental prostheses, PFM crowns in particular, ought to be avoided.

Endodontic Treatment in Switzerland. A National Survey

The purpose of this study was to collect information about current treatment protocols of endodontic procedures among general practitioners (GP), endodontically interested practitioners (EI) and endodontic specialists (ES) in Switzerland and to compare them with available endodontic quality guidelines and former surveys. A questionnaire was distributed to 1,522 attendees of two national conferences (Swiss Dental Association, 2015; Swiss Society for Endodontology, 2016) addressing socio-demographic characteristics and specific questions about root canal treatments (RCT) including techniques and materials used. Five hundred and six surveys were collected comprising data of 81.8% GP, 14.4% EI and 3.8% ES (response rate: 33.2%). The majority of respondents was male (59.9%), 40–59 years old (55.9%) with >20 years of clinical experience (54.3%). 498 participants (98.4%) stated to perform RCT. Rubber dam was always used in 52.2% of GP, 69.9% of EI and 89.5% of ES, while never-user accounted for 14.1%. Overall, 63.9% used loupes and 13.7% microscopes (mostly by ES). Rotating instruments were selected in 43.2%, followed by conventional hand-instruments (37.8%) and reciprocating instruments (19%). GP rarely activated irrigants and applied NaOCl in lower concentrations (>0.5–1%) compared to ES. GP preferred lateral compaction (57%), ES performed vertical compaction in 89.5%. 92% completed RCT after two or more visits. The majority of dentists in Switzerland follow the available quality guidelines and the present findings are coherent with internationally published surveys. Nonetheless, discrepancies are still present between daily practice and endodontic quality guidelines, especially with the routine use of rubber dam and working length determination, predominantly within the endodontic non-specialists.

Influence of Pretreatment Methods on the Adhesion of Composite and Polymer Infiltrated Ceramic CAD-CAM Blocks

PURPOSE

To assess the effect of different surface pretreatments on the shear bond strength of resin luting material on CAD-CAM composite resins and a polymer-infiltrated ceramic network (PICN).

MATERIALS AND METHODS

CAD-CAM materials (Brilliant Crios, Cerasmart, Lava Ultimate, VITA Enamic) were subjected to the following pretreatments: no pretreatment; grit blasting; grit blasting + silane; HF etching + silane; tribochemical silica coating + silane; manufacturers' specifications; manufacturers' specifications + silane; manufacturers' specifications using only the manufacturers' products including their recommended luting materials (DuoCem, G-Cem LinkForce, RelyX Ultimate, RelyX Unicem 2). Specimens were luted with resin luting material according to the Swiss shear test design. After six months of water storage, shear bond tests were performed. Data were analyzed with multiple linear regression models and nested models (α = 0.05).

RESULTS

Low bond strengths were obtained without pretreatment (Brilliant Crios 3.01 ± 0.54 MPa, Cerasmart 2.66 ± 0.47 MPa, Lava Ultimate 1.76 ± 0.26 MPa, VITA Enamic 2.83 ± 0.63 MPa). Grit blasting achieved high bond strengths across all materials (Brilliant Crios 5.17 ± 0.77 MPa, Cerasmart 4.27 ± 0.50 MPa, Lava Ultimate 3.98 ± 0.54 MPa, VITA Enamic 4.97 ± 0.90 MPa). Silane application tended to decrease bond strengths on CAD-CAM composite resins. Following the manufacturers' specifications and using their recommended materials achieved the highest bond strengths for all materials except Cerasmart (Brilliant Crios 5.75 ± 0.91 MPa, Cerasmart 2.82 ± 0.28 MPa, Lava Ultimate 6.63 ± 0.97 MPa, VITA Enamic 7.09 ± 0.77 MPa).

CONCLUSION

Grit blasting and the application of a suitable material primer is a useful pretreatment for the bonding of CAD-CAM composite resins. Silane application on CAD-CAM composite resins may entail drawbacks, possibly owing to the scarcity of silanizable fillers.

Anaesthetic management of a patient with erythropoietic protoporphyria for ventricular septal defect closure

Erythropoietic protoporphyria (EPP) is due to a deficiency in ferrochelatase required for haem synthesis. We describe the anaesthetic management of a seven-year-old with EPP undergoing closure of a haemodynamically significant ventricular septal defect. Photosensitivity in EPP patients is triggered at wavelengths near 400 nm and light-excited porphyrins generate free radicals and singlet oxygen that lead to erythrocyte deformity and haemolysis. Stimuli that could trigger a porphyric crisis during anaesthesia and surgery were reduced by avoiding exposure to the sensitive 400 nm spectrum and using light sources covered with yellow acrylate filters in the operating room. Anaesthetic agents not previously associated with porphyric crisis were chosen. Whole blood priming of the extracorporeal circuit was performed to ensure adequate haemoglobin concentrations during the perioperative period.

Exercise of linguistic control by speakers in an adult day treatment program

Ability of adults with mental retardation to exhibit linguistic "control" in informal settings within peer and staff dyads was evaluated. Results revealed that they produced significantly more utterances with staff than with peers in informal settings. However, they did not exhibit significant amounts of directives or questions, the two types of verbal control bids studied. Staff members used significantly more directives and questions as bids for control in non-peer settings than did the speakers with mental retardation in comparable peer interactions. Findings are consistent with observations of "learned helplessness" or prompt reliance within the population of persons with mental retardation. Results suggest that both staff members and adults with mental retardation have preconceived ideas on how to conduct themselves in daily interactions.

[Treatment of mucocutaneous leishmaniasis with pentamidine isothionate]

BACKGROUND

The mucocutaneous form of New World cutaneous leishmaniasis is caused, theoretically, by Leishmania (viannia) braziliensis. Pentad valency antimonic compounds are widely used for treatment of New World cutaneous leishmaniasis. The rate of recurrence is often high when these drugs are used for mucocutaneous forms. Pentamidine has been considered as a second line treatment although little data is available.

PATIENTS AND METHODS

Seventeen patients with mucocutaneous leishmaniasis were treated with pentamidine isothionate, 4 mg/kg every 48 hours. A complete oto-rhino-laryngological examination was performed once a week to determine the course of the lesions. Treatment was discontinued when the lesions healed. A follow-up oto-rhinolaryngological examination was also performed after treatment withdrawal and every three months thereafter for an undetermined period.

RESULTS

Lesions healed with pentamidine isothionate in 16 patients (94%). Mean dosage required was 2872 mg (2025-4320 mg) for a mean treatment duration of 22 days (12-32 days). Mean follow-up was 13.3 months (3-37 months). Leishmaniasis relapsed in one patient 4 months after treatment withdrawal.

DISCUSSION

Pentamidine isothionate is an effective treatment for mucocutaneous leishmaniasis, providing cure with a low rate of recurrence.

Controversies in management of sternal tumors

The rarity of sternal tumors makes a good comparative study a difficult task. Controversies exist on questions of method of surgical diagnosis, the extent of the surgical procedure, and the different ways and means of reconstruction. We describe a case that was believed to be a clear case of chondrosarcoma but was actually a plasmacytoma. From the evidence of this case and a review of the literature we conclude that almost any plasmacytoma should be considered generalized multiple myeloma. Biopsy should be performed in all cases of sternal tumor before any surgical action is taken.

Transrectal ultrasound used in office practice to aid in the diagnosis of carcinoma of the prostate

Transrectal ultrasound and TRUS-guided needle biopsy was studied in office practice to detect prostate cancer in men with palpably irregular prostates or elevated tumor markers (PAP/PSA). Of 330 men examined, 118 had TRUS biopsy: 33 were positive for adenocarcinoma, 13 were small volume, low stage lesions treated by R.R.P. Twenty-eight percent of all patients biopsied had adenocarcinoma: 11% (13) had low volume, low stage disease potentially curable by radical surgery, representing 4% of the total studied. TRUS in combination with markers does aid in the diagnosis of low stage prostatic adenocarcinoma. It is a practical, useful, office-based urologic procedure.

Anomalies associated with cleft lip, cleft palate, or both

Numerous investigators have reported on a low frequency of other anomalies in patients with cleft lip, cleft palate, or both. The data have been somewhat inconsistent, ranging from a 3% to over 30% frequency of associated malformations. However, a recent study concluded that over half of the children with clefts at a large metropolitan center have associated anomalies. In an effort to elucidate further the genetic and morphologic characteristics of patients with clefts, 1,000 patients with clefts of the lip, palate, or both were examined and reviewed. The results indicate that associated anomalies occur in 63.4% of the sample. Approximately half of the patients with multiple anomalies have recognized syndromes, sequences, or associations, while the other half have physical examination (apparently one-of-a-kind) syndromes. The high frequency of associated anomalies has obvious implications for the genetic counseling offered to all patients at cleft palate and craniofacial centers. The frequency of associated anomalies also raises questions regarding the validity of past genetic research involving populations of subjects with clefts.

Routine fetal heart rate monitoring in the antepartum period

A total of 4517 successful antepartum nonstress tests (NST) was performed on 2003 high- (28%) and low- (72%) risk obstetric patients. Most patients were monitored from 32 to 34 weeks' gestation onward. A reactive NST was defined as 2 accelerations in 10 minutes--15 beats/min minimum amplitude; 15 seconds minimum duration. The test was repeated at the next visit in low-risk patients with reactive NST or in 1 week in high-risk patients with this response. Nonreactive tests were followed immediately by a stress test in high-risk patients, but only after repeat nonreactive NST within 24 hours in low-risk patients. About 88% of low-risk and 86% of high-risk patients demonstrated ractive NST only. Late decelerations during subsequent stress testing or labor, low Apgar scores, and perinatal deaths were more common in low-risk pregnancies than in high-risk pregnancies and more common in those with nonreactive NST than in those with reactive NST. High-risk/reactive NST babies, however, fared better than low-risk/nonreactive NST babies. Of the 16 perinatal deaths 6 died antepartum, 2 died in labor, and 8 died as neonates. Presumed asphyxia accounted for 6 deaths while significant anomaly accounted for 5; sepsis and trauma accounted for 2 each. In only 2 instances was a reactive NST followed by a death from apparent asphyxia. Routine NST testing appears to improve the resolution of maternal risk classification and may contribute to better perinatal outcome.

The role of intraaortic balloon counterpulsation in patients undergoing cardiac operations

Intraaortic balloon counterpulsation (IABC) was used to assist 60 patients undergoing cardiac operations for reasons of acute left ventricular failure (18 patients) or electively for indications in high-risk coronary and valvular heart disease (42 patients). Nine of 18 patients achieved hemodynamic stability when treated for acute perioperative or postoperative cardiogenic shock. Four of these died from problems unassociated with postoperative left ventricular failure and 5 were long-term survivors, indicating a potential salvage of 50%. In 42 high-risk patients, IABC was used electively to control preinfarction angina before operation (21 patients) and prophylactically to prevent postoperative low-output failure in another 21 patients with severe coronary and valvular heart disease. Thirty-nine, or 93%, of these patients survived. There were no deaths in the preinfarction angina group, 1 death in the group with coronary disease and ejection fractions less than 30%, and 2 deaths in those with valvular heart disease and congestive failure. Seven patients developed thrombotic or ischemic complications, but no permanent damage resulted. IABC is an important form of assistance for any patient with preoperative, intraoperative, or postoperative left ventricular failure and adds safety and hemodynamic stability for the high-risk patient with preinfarction angina or poor ventricular function.