A novel model for curriculum design: Preparation, planning, prototyping, and piloting

Dental education continuously strives to provide students with positive and meaningful learning experiences. Developing or improving a curriculum usually encompasses three main phases: design, implementation, and evaluation. Most research on curriculum development in dental education has focused on the last two phases. Our commentary addresses this gap by describing a new model for curriculum design that effectively guided the design phase of the complete overhaul of the four-year Doctor of Dental Surgery curriculum at the School of Dentistry, University of Alberta. Built on the strengths of pre-existing curriculum design models, the new model provided enough structure and rigour to support the complexity required during a complete curriculum redesign whilst still allowing sufficient consultation and flexibility to encourage stakeholder engagement. The steps of the new 4P's model (preparation, planning, prototyping, and piloting) and main actions within each step are described. Challenges observed in each step and strategies to address them are reported. Other institutions embarking on renewing or redesigning a curriculum at a program level may benefit from using a curriculum design process similar to the 4P's model. Recommendations are discussed including the inclusion of educational consultants in the curriculum renewal committee, the importance of a leadership that effectively supports curriculum reform, purposeful engagement of stakeholders during each step of the design phase and ensuring that project and change management occur concurrently.

Lobodontia in the primary and permanent dentition: a condition requiring individualized care

Lobodontia is a rarely documented dental condition associated with pointed or conical cusps on premolars and canines, multitubercular occlusal surfaces on molar teeth, and irregularly shaped incisors. Information on this uncommon condition continues to be scarce, with particularly little information available on the primary dentition. The purpose of this article is to describe 6 cases of lobodontia and discuss the variability in presentation and management. Previously unreported manifestations in the primary dentition are included. The cases described in the current study demonstrate the spectrum of clinical and radiographic features of the condition, and show that a varied, individualized approach to treatment is necessary.

Development of an electronic learning progression dashboard to monitor student clinical experiences

INTRODUCTION

Clinical experience tracking mechanisms for students at dental schools provide patient assignment, student experience, and learning progression feedback. The purpose of this study was to evaluate dental students' clinical experiences following the implementation of a learning progression dashboard (LPD).

METHODS

After developing and deploying an electronic LPD using PHP, secondary data analysis on dental students' clinical experiences from 2017-2019 was conducted. Student experience differences were compared between the year before continuous use of the LPD and the first year using it. LPD data contained the required clinical procedures dentistry students must perform across all disciplines and the number of planned, in progress, and completed tasks each student has accomplished. Using two time points, the students' experiences were compared. Univariate statistics and independent t-tests were conducted in R for detecting the differences in the number and categories of codes.

RESULTS

The number and category of codes showed significant differences between the academic year 2017-2018 and 2018-2019 for both third- and fourth-year dental students after one and two terms. Overall, students recorded a 26% greater number of treatment codes and experienced a 26% greater number of code categories compared to the previous year.

CONCLUSION

Applying information management methods such as dashboards can better inform educators on student clinical experiences and improve clinical learning outcomes for students.

Dental faculty and student views of didactic and clinical assessment: A qualitative description study

OBJECTIVE

Although assessment is essential to accurately represent student learning, little is currently known about student and faculty perceptions of assessment in dental schools. Our study aimed to explore faculty and student views of didactic and clinical assessments in the School of Dentistry at the University of Alberta.

METHOD

Qualitative description informed the study design. Data were collected through focus groups and analysed inductively using manifest content analysis.

RESULTS

Five focus groups were conducted with faculty (n = 34) and three with students (n = 19). Faculty and student views of assessment were related to improvements made (perceived positive changes), improvements needed (perceived limitations) and improvements recommended (recommendations to improve perceived limitations). Faculty and students reported that improvements made (eg adequacy of assessment to students' levels of training) varied across instructors, courses and learning environments. Both faculty and students perceived clinical assessments as less appropriate than didactic assessments. Faculty perceived limitations were mostly related to assessment appropriateness, especially assessment accuracy and comprehensiveness, whilst student perceived limitations included other issues related to appropriateness (eg misalignment with course objectives) as well as issues related to assessment volume, pace and scheduling. Similarly, faculty recommendations focused on enhancing the assessment of clinical competencies, whilst students' recommendations aimed to also improve assessment scheduling, volume and usage (eg for learning purposes).

CONCLUSIONS

Faculty and student views of assessment complemented one another. Our data show that assessment in dental education is multidimensional, so that multilevel strategies may be needed to improve this component of dental curricula.

Intraoral Imaging in Dental Private Practice - A Rectangular Collimator Study

OBJECTIVE

To gain a better understanding of the extent to which rectangular collimation is being used in private practice and the barriers to adoption by practitioners.

METHODS

Licensed dentists in private practice were asked to answer a survey composed of 17 multiple-choice questions and 1 open-ended question regarding demographics, radiation safety, image receptor type, intraoral imaging techniques and use of rectangular collimation.

RESULTS

Among all participants (n = 82), 86.6% used digital systems (n = 71) and 13.4% conventional film (n = 11). Most (74.0%, n = 60) were aware of the benefits of using rectangular collimation, with 5.5% reporting not knowing of the existence of this device (n = 3). Only 12.9% of the dentists reported using rectangular collimation routinely (n = 10). The youngest and oldest age groups had the lowest compliance rates, 5.6% and 0%, respectively.

CONCLUSION

Although 74.0%, (n = 60) of private practitioners were aware of the benefits of using rectangular collimation to reduce radiation dose, only 12.2% (n = 10) used it routinely for intraoral imaging. Barriers to implementing rectangular collimation in private practice settings included challenges in training support staff and fear of an increase in the occurrence of technical errors that would result in re-exposure of patients.

Thinking ecologically about clinical education in dentistry

Traditional approaches to clinical education (CE) in dentistry have primarily focused on the needs and interests of students (student-centred), patients (patient-centred) or individuals receiving care (person-centred). Research has shown that giving priority to the interests of one stakeholder (eg students) may negatively affect the interests of others (eg patients, instructors and administrators). In this commentary, we discuss some limitations of traditional approaches to CE and suggest an eco-centred approach that assumes that the interests of all stakeholders must be considered when planning CE due to the interdependent relationships between stakeholders. A description of this new approach is provided, whilst research and innovation are encouraged to develop an ecologically informed system of CE.

Assessing students' confidence in interpreting dental radiographs following a blended learning module

OBJECTIVE

This study assessed senior dental hygiene (DH) students' self-reported confidence in interpreting dental radiographs following the introduction of a blended learning (BL) module for radiology interpretation. The assessment of students was conducted five months prior to graduation.

METHODS

A BL oral radiology module was designed. In order to capture the context, descriptions and differences of students' experience and confidence, a qualitative research approach was selected. Data were captured using a semi-structured interview process and analysed using phenomenographic methods.

RESULTS

Sixteen students were interviewed. Blinded transcripts were analysed, and the main themes relating to confidence were extracted and arranged into categories. The categories were coded as to how confident (low, medium or high) each of the students felt specific to varying contexts and complexities of radiographic interpretation.

CONCLUSION

Predominately, the BL model had a positive impact on DH students' confidence in the interpretation of radiographic findings. However, when asked about their level of overall confidence in interpreting dental radiographs, students still did not describe themselves as confident for all potential findings on radiographs at this point in their education. The students highlighted the importance of having patient history details and clinical assessment findings included in the interpretation exercises and expressed a desire to collaborate with other professionals when interpreting radiographs.

Evidence on radiation dose reduction using rectangular collimation: a systematic review

BACKGROUND

The goal of an intraoral radiograph is to be a valuable diagnostic tool while keeping the radiation exposure dose as low as reasonably achievable. The International Commission on Radiological Protection (ICRP) has strong recommendations for patient dose-reduction strategies.

OBJECTIVE

To answer the following research question: 'In either patient or in phantoms, does rectangular collimation compared with other forms of collimation reduce the radiation absorbed dose during intraoral imaging?'

METHODS

The search strategy was developed specifically for each electronic database. Information was collected from MEDLINE, all EBM Reviews including the Cochrane Library, EMBASE, LILACS, PubMed and Web of Science, and from a search of the grey literature via Google Scholar. Studies were included if they reported the radiation dose in intraoral imaging using rectangular collimation compared with any other type of collimation or the absence of it. Studies that did not involve comparison/control groups were excluded. A qualitative appraisal of the included studies was performed. The Methodological Index for NOn-Randomised Studies (MINORS) tool assessed the potential risk of bias among the studies, while the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach determined the level of available evidence.

RESULTS

Thirteen studies using different types of receptors, including D-speed film, E-speed film, phosphor storage plates (PSP) and direct digital sensors, were included. Different methods to access absorbed and effective dose by exploring distinct technical parameters, such as distance object-receptor, long- and short-cone, kVp and mA, exposure time and beam filtering, were used. High heterogeneity between the studies was found. The level of evidence was classified as moderate. The radiation dose reduction ranged from 40% to 92% compared with circular collimation. The limitations of the cross-sectional design and in vivo studies were discussed. As this systematic review applied validated tools and guidelines designed for population-based studies, the application for studies based on computer simulations and dosimetry measurements was challenging.

CONCLUSION

There is moderate evidence suggesting that rectangular collimation significantly reduces radiation dose when compared with round collimation, justifying its implementation in clinical settings/private practices while taking intraoral radiographs.

Digital Intraoral Imaging Re-Exposure Rates of Dental Students

A guiding principle of radiation safety is ensuring that radiation dosage is as low as possible while yielding the necessary diagnostic information. Intraoral images taken with conventional dental film have a higher re-exposure rate when taken by dental students compared to experienced staff. The aim of this study was to examine the prevalence of and reasons for re-exposure of digital intraoral images taken by third- and fourth-year dental students in a dental school clinic. At one dental school in Canada, the total number of intraoral images taken by third- and fourth-year dental students, re-exposures, and error descriptions were extracted from patient clinical records for an eight-month period (September 2015 to April 2016). The data were categorized to distinguish between digital images taken with solid-state sensors or photostimulable phosphor plates (PSP). The results showed that 9,397 intraoral images were made, and 1,064 required re-exposure. The most common error requiring re-exposure for bitewing images was an error in placement of the receptor too far mesially or distally (29% for sensors and 18% for PSP). The most common error requiring re-exposure for periapical images was inadequate capture of the periapical area (37% for sensors and 6% for PSP). A retake rate of 11% was calculated, and the common technique errors causing image deficiencies were identified. Educational intervention can now be specifically designed to reduce the retake rate and radiation dose for future patients.

Digital Imaging Capability for Caries Detection

The objective of this study was to identify the diagnostic capability of photostimulable phosphor plates (PSPs) and direct digital sensors (DDSs) in the detection of interproximal caries. Studies were identified that evaluated the diagnostic capability of PSPs and DDSs in detecting interproximal caries in human teeth, in both dentin and enamel. Histologic sections were the gold standard. This systematic review searched several electronic databases. In addition, Google Scholar and reference lists of the finally included studies were screened. QUADAS-2 was applied to evaluate the risk of bias among included studies. Six studies were finally included; 4 of which were considered homogeneous enough to conduct a meta-analysis. The meta-analysis evaluated 668 interproximal human tooth surfaces. All studies used extracted human teeth ranging from no caries present to caries into dentin. Each tooth was radiographed by both PSP and DDS technologies and then submitted for histologic analysis as the gold standard. Meta-analysis showed that intraoral digital imaging is of high specificity but low sensitivity in the detection of interproximal caries. The sensitivity and specificity for different studies with PSPs varied substantially from 15% to 54% and from 84% to 100%, respectively. Direct sensor analysis sensitivity and specificity ranged from 16% to 56% and from 90% to 100%, respectively. Newer PSP and DDS technologies had statistically significant higher sensitivities, yet the differences in diagnostic capabilities between the older and newer technologies were clinically insignificant. Both digital systems were excellent in identifying surfaces without caries (specificity) but were not sensitive enough to reliably identify interproximal surfaces with caries. Clinicians must therefore remain vigilant in performing a careful clinical examination and other diagnostic tests rather than relying solely on radiographic imaging to diagnose interproximal caries.

Knowledge Transfer Statement: This study will help clinicians make an evidence-based decision when deciding which digital radiography system to use when evaluating interproximal caries. Time, patient radiation safety, cost, and image quality are factors to be considered. The performance of the different available digital imaging systems was compared with the current gold standard—a histologic analysis—via meta-analysis.

Role of the Internet as an information resource for surgical patients: a survey of 877 patients

BACKGROUND

This study was conducted to provide preliminary data regarding current Internet use practices for information about anaesthesia in patients undergoing elective surgical procedures at a major academic institution.

METHODS

With IRB approval, 2936 patients coming for preanaesthetic evaluation at a tertiary academic hospital's preadmission testing (PAT) centre were invited to voluntarily participate in a 20-item questionnaire designed to obtain participants' characteristics and Internet use for information pertaining to their upcoming surgery. Data were analysed using statistical software SAS (Cary, NC, USA). Descriptive statistics were calculated for continuous variables using mean (sd), and for categorical data using n (%). Association analysis was performed using the Fisher's exact test.

RESULTS

Eight hundred and seventy-seven patients (30%) responded. Of these, 356 (41%) looked for information about their medical condition, 321 (37%) for their surgery, 279 (32%) for surgeon, 163 (19%) for the hospital, and only 36 (4%) for information regarding anaesthesia. Of these 36 patients, 14 (39%) said the sites they used helped answer their questions regarding anaesthesia. Of the 831 patients who did not use the Internet for anaesthesia, 503 (57%) indicated that they would be receptive to being directed to specific websites for anaesthesia.

CONCLUSIONS

Of the patients coming for elective surgery who responded (30%), the majority did not use the Internet to seek information regarding anaesthesia. Respondents indicated a high degree of interest in being directed to appropriate websites for further information. These results suggest that it may be beneficial to include information regarding reliable web-based resources to interested patients at preoperative visits.

Beagle 2: a proposed exobiology lander for ESA's 2003 Mars Express mission

The aim of the proposed Beagle 2 small lander for ESA's 2003 Mars Express mission is to search for organic material on and below the surface of Mars and to study the inorganic chemistry and mineralogy of the landing site. The lander will have a total mass of 60kg including entry, descent, and landing system. Experiments will be deployed on the surface using a robotic arm. It will use a mechanical mole and grinder to obtain samples from below the surface, under rocks, and inside rocks. Sample analysis by a mass spectrometer will include isotopic analysis. An optical microscope, an X-ray spectrometer and a Mossbauer spectrometer will conduct in-situ rock studies.

A major glycoprotein of the nuclear pore complex is a membrane-spanning polypeptide with a large lumenal domain and a small cytoplasmic tail

One of a small number of polypeptides of the nuclear pore complex that have been identified is a major glycoprotein called gp210. Since it is very resistant to chemical extractions from membranes, gp210 was suggested to be integrated into nuclear membranes. In this study we have determined the membrane topology of this protein by biochemical and immunological approaches. We found that limited proteolysis of isolated nuclear envelopes with papain released a 200 kd water-soluble fragment of gp210 containing concanavalin A-reactive carbohydrate. Immunogold electron microscopy with a monoclonal antibody showed that this domain is localized on the lumenal side of nuclear membranes at pore complexes. Anti-peptide antibodies against two sequences near the C-terminus of gp210 were used to map possible membrane spanning and cytoplasmically disposed regions of this protein. From analysis of the protease sensitivity of these epitopes in sealed membrane vesicles, we determined that gp210 contains a small cytoplasmic tail and only a single membrane-spanning region. Thus, gp210 is a transmembrane protein with most of its mass, including the carbohydrate, located in the perinuclear space. This topology suggests that gp210 is involved primarily in structural organization of the pore complex, for which it may provide a membrane attachment site.

Integral membrane proteins specific to the inner nuclear membrane and associated with the nuclear lamina

We obtained a monoclonal antibody (RL13) that identifies three integral membrane proteins specific to the nuclear envelope of rat liver, a major 75-kD polypeptide and two more minor components of 68 and 55 kD. Immunogold labeling of isolated nuclear envelopes demonstrates that these antigens are localized specifically to the inner nuclear membrane, and that the RL13 epitope occurs on the inner membrane's nucleoplasmic surface where the nuclear lamina is found. When nuclear envelopes are extracted with solutions containing nonionic detergent and high salt to solubilize nuclear membranes and pore complexes, most of these integral proteins remain associated with the insoluble lamina. Since the polypeptides recognized by RL13 are relatively abundant, they may function as lamina attachment sites in the inner nuclear membrane. Major cross-reacting antigens are found by immunoblotting and immunofluorescence microscopy in all rat cells examined. Therefore, these integral proteins are biochemical markers for the inner nuclear membrane and will be useful models for studying nuclear membrane biogenesis.

Monoclonal antibodies identify a group of nuclear pore complex glycoproteins

Using monoclonal antibodies we identified a group of eight polypeptides of rat liver nuclear envelopes that have common epitopes. Most or all of these proteins are structurally distinct, as shown by tryptic peptide mapping and analysis with polyclonal antibodies. While these polypeptides are relatively tightly bound to nuclear membranes, only one is an integral membrane protein. The eight antigens cofractionate with the nuclear pore complex under various conditions of ionic strength and detergent. It can be seen by immunofluorescence microscopy that the monoclonal antibodies reacting with these antigens stain the nuclear surface of interphase cells in a finely punctate pattern. When the nuclear envelope is disassembled and subsequently reformed during mitosis, the proteins are reversibly dispersed throughout the cytoplasm in the form of minute foci. By EM immunogold localization on isolated nuclear envelopes, the monoclonal antibodies label exclusively the nuclear pore complex, at both its nucleoplasmic and cytoplasmic margins. Considered together, our biochemical and localization data indicate that the eight nuclear envelope polypeptides are pore complex components. As shown in the accompanying paper (Holt, G. D., C. M. Snow, A. Senior, R. S. Haltiwanger, L. Gerace, and G. W. Hart, J. Cell Biol., 104:1157-1164) these eight polypeptides contain a novel form of glycosylation, O-linked N-acetylglucosamine. The relative abundance and disposition of these O-linked glycoproteins in the pore complex are consistent with their having a role in nucleocytoplasmic transport.

Nuclear pore complex glycoproteins contain cytoplasmically disposed O-linked N-acetylglucosamine

A novel form of protein-saccharide linkage consisting of single N-acetylglucosamine (GlcNAc) residues attached in O-linkages directly to the polypeptide backbone has been described (Holt, G. D., and G. W. Hart, 1986, J. Biol. Chem., 261:8049-8057). This modification was found on proteins distributed throughout the cell, although proteins bearing O-linked GlcNAc moieties were particularly abundant in the cytosolic and nuclear envelope fractions of rat liver. In the accompanying article (Snow, C. M., A. Senior, and L. Gerace, 1987, J. Cell. Biol., 104: 1143-1156), the authors describe monoclonal antibodies directed against eight proteins localized to the nuclear pore complex. These proteins occur on the cytoplasmic and nucleoplasmic (but not lumenal) sides of nuclear membranes. In this report, we demonstrate that all members of this group of pore complex proteins bear multiple O-linked GlcNAc residues. Further, we show that the O-linked GlcNAc moieties are linked via serine (and possibly threonine) side chains to these proteins. Perturbing the O-linked GlcNAc residues either by covalently attaching galactose to them or by releasing them with beta-N-acetylglucosaminidase strongly diminishes the immunoreactivity of the proteins with all of the monoclonal antibodies. However, the O-linked GlcNAc moieties are only part of the epitopes recognized, since O-GlcNAc-containing limit pronase fragments of nuclear pore complex proteins cannot be immunoprecipitated by these antibodies. These findings, taken together with those in the accompanying article, are a direct demonstration that proteins of the cytoplasm and nucleoplasm bear O-linked GlcNAc residues.

Genomes of endogenous and exogenous avian retroviruses

The endogenous viruses of chickens are closely related to the exogenous avian leukosis viruses (ALV) yet as a group differ from these viruses in their host range, growth rate, and oncogenicity. The present study was undertaken to determine the patterns of relationship among the genomes of endogenous and exogenous ALVs. Complete or partial T1 oligonucleotide maps were prepared from the genomes of endogenous viruses that reside at eight distinct loci in chickens. Selected endogenous viruses and recombinants of endogenous or endogenous and exogenous viruses were characterized for host range and growth rate. From these data we could infer the following: (1) Endogenous viruses form a distinct lineage of ALVs with the most distinctive differences occurring in the portion of env that encodes host range and the U3 portion of the long terminal repeat; (2) The U3 sequences of endogenous ALVs determine the low growth rates of these viruses; and (3) Endogenous ALVs have distinctive oligonucleotide markers that allow them to be subclassified into distinct lineages. Our results suggest that endogenous viruses are derived from one another and not from exogenous field strains of ALV. This phenomenon may be related to the unique env encoded host range of endogenous ALVs, their unique U3 encoded growth rates, or perhaps their unique access, as residents of germ line DNA, to germ line cells.