Well-being of undergraduate dental students: Questionnaire design, findings and future directions

INTRODUCTION

The recent pandemic has highlighted the importance of addressing well-being in the overall health of students. There is a need for support systems within dental schools to help students demonstrate resilience, adapt to learning environments and thrive in their professional careers.

OBJECTIVES

The main aim of the study was to evaluate Bachelor of Dental Surgery (BDS) students' understanding and experience of well-being. The objectives were to create a suitable survey to assess students' well-being, investigate the factors affecting dental students' well-being and develop a student well-being action plan based on the analysis of the survey.

METHODS

A literature review was conducted to identify and critically assess existing measures of well-being in dental students. Four domains of well-being (emotional, physical, social, intellectual) relevant to dental students were identified. Through a comprehensive iterative process, a two-part survey was developed and tested, which measured individual experiences of well-being across the four domains and collected feedback on proposed initiatives to support student well-being. The survey was disseminated to all 452 dental students from Years 1 through 6, of which 71% (321) responded.

RESULTS

The survey revealed low levels of overall well-being among the dental student population, which worsened with increasing years of clinical study. Fear of failing exams presented the biggest challenge with regard to emotional well-being, while sleep deprivation and occupational health hazards most affected the physical well-being domain. Intellectual well-being was compromised by insufficient free time to pursue extracurricular interests and concerns about achieving the required skills. Despite a majority experiencing positive relationships with their peers and tutors, less than a fifth agreed that the Faculty of Dentistry 'supported my well-being as a dental student'.

CONCLUSION

As the first investigation of the well-being of dental students in Hong Kong, the key stressors identified were examinations, long schedules and the physical burden of dental work, which are consistent with international literature. The findings reveal students' needs and preferences for well-being initiatives which will be optimized in the implementation of student-centred curricular activities.

Near-peer teaching in a psychomotor skills course: Benefits, challenges and solutions

INTRODUCTION

This study evaluates the perceptions and experiences of students in the role of near-peer teachers in a psychomotor skills course.

MATERIALS AND METHODS

Final year BDS students were invited to participate as near-peer teachers in a 4th-year conventional bridges course. Near-peer teachers attended eight sessions (3 h) of simulation laboratory teaching relating to conventional bridge tooth preparations and provided feedback on near-peer tooth preparations and answered their questions. Interviews were conducted with all near-peer teachers to evaluate their perceptions of this novel teaching and learning experience and a thematic analysis was performed to analyse the data.

RESULTS

Near-peer teachers reported this to be a rewarding, enjoyable and challenging experience. They benefited from learning and revising content-related materials as well as gained insights and teaching skills through the peer teaching process. Students felt supported and learned from peers and teaching staff and some used dyad teaching as a strategy to overcome perceived challenges. Students also reported the benefits of social and cognitive congruence in interacting with junior peers. However, students reported the feeling of inadequacy or lack of confidence and suggested the need for a training to prepare them better for the course.

CONCLUSION

This paper reports on the benefits as well as challenges perceived by near-peer teachers during simulation laboratory teaching experience. We provide solutions into how to better prepare students for such teaching experience.

A qualitative analysis of dentists' understanding and management of non-carious cervical lesions (NCCL)

INTRODUCTION

Non-carious cervical lesions (NCCLs) are considered to have a multi-factorial aetiology and their management is affected by a range of variables perhaps most importantly clinical judgement. The aim of this study was to elicit information from practicing dentists, using interviews, to explore their understanding of NCCL aetiology, the decision-making criteria of when to restore, and the restorative techniques used to restore NCCLs. This may help identify gaps or anomalies in our understanding to inform future research and clinical practice for the management of NCCLs.

METHODS

An interview guide was developed from a literature search which formed 2 domains framed around understanding and management of NCCLs based on: understanding of diagnosis and aetiology, and factors affecting decision making for management. Practicing dentists with more than 10 years of experience were purposively recruited to conduct in-depth, semi-structured interviews. Fifteen interviews were audio recorded and transcribed verbatim. A thematic content analysis was conducted and the results analysed.

RESULTS

From the thematic analysis, 2 domains were identified. In the domain of "diagnosis and aetiology", while participants have similar understanding and methods of diagnosing NCCL, most stated NCCLs in a patient were caused by a "main aetiology" such as "abrasion", "abfraction" while few described the inter-relationship of these aetiological factors. In the domain of "factors affecting decision making". "Patient reported symptoms" and "lesion dimension" were the main factors that affected participants' decision to provide restorative or non-restorative management. However, a "restorative threshold" was not able to be identified.

CONCLUSION

There was notable variety in participants' understanding of the aetiology, management, and treatment of NCCLs, particularly the restorative threshold of when to treat.

CLINICAL SIGNIFICANCE

The variability demonstrates the need to have a clearer understanding of the key elements that affect the management of NCCLs and better information to support the decision of when to treat.

Reliability of online dental final exams in the pre and post COVID-19 era: A comparative study

Amidst the fourth COVID-19 wave in Viet Nam, national lockdowns necessitated the closure of numerous dental schools. To assess DDS (Doctor of Dental Surgery) graduation exams, this study analyzed their 2021 implementation in comparison to onsite exams conducted in 2020 and 2022 at the Faculty of Odonto-Stomatology, University of Medicine and Pharmacy at Ho Chi Minh City, Viet Nam (FOS-UMPH). The final online examination comprises two main sessions: a synchronous online examination using FOS-UMPH e-Learning for theories (consisting of 200 MCQs and 3 written tests with 3 clinical situations needed be solved) and a synchronous online examination using Microsoft Teams for practicum (comprising of 12 online OSCE stations). The final grades were evaluated using the same metrics in face-to-face final examinations in 2022 and 2020. A total of 114, 112 and 95 students were recruited for the first-time exams in 2020, 2021 and 2022, respectively. In order to analyze the reliability, histogram and k-mean clustering were employed. The histograms from 2020, 2021 and 2022 showed a striking similarity. However, fewer students failed in 2021 and 2022 (13% and 12.6%, respectively) compared to 2020 (28%), with clinical problem-solving part grades (belonging to theory session) being notably higher in 2021 and 2022. Intriguingly, the MCQ Score results showed the identical patterns. The courses of orthodontics, dental public health, and pediatrics subjects (in the group of prevention and development dentistry) stood out for their exceptional accuracy across both sessions. After examining data gathered over three years, we identified three distinct clusters: the first comprised of scattered average and low scores, the second characterized by high scores but unstable and scattered and the third cluster boasting consistently high and centered scores. According to our study, online and onsite traditional graduation exam results are relatively equivalent, but additional measures are necessary to standardize the final examination and adapt to the new normal trend in dental education.

An exploration of clinical communication needs among undergraduate dental students

INTRODUCTION

This study examines undergraduate dental students' perceptions of their self-confidence in communicating with patients and paradental staff.

MATERIALS AND METHODS

A survey questionnaire was designed based on a literature review and input from students and academic staff relating to clinical communication skills with 19 questions across 7 domains. Through email, a convenience sampling of undergraduate students were invited to complete the survey questionnaire. Qualitative and quantitative analysis of the responses was performed with a thematic analysis to the open-ended questions.

RESULTS

In total, 102 students were surveyed from 4 years of students with a 36.6% response rate. Students reported some areas of low confidence across various communication domains, in particular, building rapport, behavioural change, management of patient expectation and breaking bad news. Students reported insufficient confidence and knowledge in specialist clinical areas, layperson terms and success rates and longevity of treatment items when communicating with patients. Information sheets and visual aids such as models or photos were suggested by students to be helpful in patient communication. Students also reported challenges in communication with nurses when they might challenge or change their clinical decisions in front of their patients.

CONCLUSION

Our study reveals areas of low confidence among undergraduate dental students in communication towards patients and paradental staff. Barriers and challenges have been identified with an action plan suggested accordingly. There is a need for additional training in the form of learning content and communications experiences, and channels of communications for undergraduate students.

Near-peer teaching for learning clinical photography skills: Perceptions of students

AIM

This paper evaluates the perceptions and experience of students, in the role of both near-peer teacher and learner who participated in the clinical dental photography course, using a mixed-method analysis with focus group interviews of student tutors and a questionnaire of learner perceptions.

METHODS

A student-led course on Digital Clinical Photography took place with BDS 5 and 6 students as near-peer teachers (NPTs) and BDS 2 and 3 students as learners. Interviews were conducted with near-peer teachers, and a questionnaire was distributed to learners to evaluate students' perceptions of this novel teaching and learning experience.

RESULTS

Near-peer teaching has proven to be a beneficial alternative teaching pedagogy which was well-received by NPTs and student learners. The content creation and teaching experience deepened NPTs' understanding on the subject matter and were motivated given the autonomous nature of the project. NPTs enjoyed and benefited from the collaborative nature of the project and the relevance of the subject matter and improved their clinical skills. The student learners enjoyed the learning experience and benefits of learning from NPTs which is supported by social and cognitive congruence. The positive perception of teaching and learning in pairs were also described.

CONCLUSION

This project demonstrates the perceived benefits of near-peer teaching for clinical photography skills for student experiential learning and highlights key elements on how to structure such an activity to engage and support students to participate in such future activities.

A flipped classroom, same-level peer-assisted learning approach to clinical skill teaching for medical students

Background

Clinical procedural skills are vital components of medical education. Increased student intake and limited capacity of medical schools necessitate more efficient ways to deliver clinical skill teaching. This study employed a flipped classroom, peer-assisted learning approach to deliver clinical skill teaching. It aimed to determine the influence of pre-class demonstration video watching and in-class student-student interactions on clinical skill acquisition.

Methods

In 2017, a cohort of 205 medical students in their penultimate year of undergraduate medical study were recruited, and they learned bag mask ventilation and intravenous cannulation during this study. The participants watched a demonstration video before class, and then underwent self-directed practice as triads. Afterwards, each participant video-recorded their skill performance and completed post-class questionnaires. The videos were evaluated by two blinded assessors.

Results

A hundred and thirty-one participants (63.9%) completed the questionnaire. For bag mask ventilation, participants who claimed to have watched the corresponding demonstration video before class achieved higher performance scores (those who watched before class: 7.8 ± 1.0; those who did not: 6.3 ± 1.7; p < 0.01). For intravenous cannulation, while there is no significant difference in performance scores (those who watched before class: 14.3 ± 1.3; those who did not: 14.1 ± 1.4; p = 0.295), those who watched the video before class received less interventions from their peers during triad practice (those who watched before class: 2.9 ± 1.8; those who did not: 4.3 ± 2.9; p < 0.05). The questionnaire results showed that most participants preferred the new approach of clinical skill teaching and perceived it to be useful for skill acquisition.

Conclusion

The flipped classroom, same-level peer-assisted learning model is potentially an effective way to address the current challenges and improve the efficiency of clinical procedural skill teaching in medical schools.

Compositional profile of mucosal bacteriome of smokers and smokeless tobacco users

INTRODUCTION

Smoked, and especially smokeless, tobacco are major causes of oral cancer globally. Here, we examine the oral bacteriome of smokers and of smokeless tobacco users, in comparison to healthy controls, using 16S rRNA gene sequencing.

METHODS

Oral swab samples were collected from smokers, smokeless tobacco users, and healthy controls (n = 44). Microbial DNA was extracted and the 16S rRNA gene profiled using the Illumina MiSeq platform. Sequencing reads were processed using DADA2, and taxonomical classification was performed using the phylogenetic placement method. Differentially abundant taxa were identified using DESeq2, while functional metagenomes based on KEGG orthology abundance were inferred using LIMMA.

RESULTS

A significantly higher microbial diversity was observed in smokeless tobacco users and smokers relative to controls (P < 0.05). Compositional differences in microbial communities were observed in all comparisons with healthy controls (PERMANOVA P < 0.05) but not between smokers and smokeless tobacco users. Levels of Fusobacterium spp., Saccharibacterium spp., and members of Shuttleworthia were elevated in smokers when compared to controls (BH adj P < 0.01). In addition, the relative abundance of three bacterial taxa belonging to genera Fusobacterium spp., Catonella, and Fretibacterium spp. was significantly increased in smokeless tobacco users relative to controls (BH adj P < 0.01). Major functional pathways significantly increased in smokeless tobacco users relative to both controls, and smokers were similar and involved amino acid metabolism including glutamate and aspartate biosynthesis and degradation (log FC > 1.5; BH adj P < 0.01).

CONCLUSIONS

A distinct taxonomic and functional profile of oral microbiome in smokers and smokeless tobacco users as compared to healthy controls implicates a significant role of microbes and their metabolites in diseases associated with tobacco use including oral cancer.

CLINICAL RELEVANCE

Future efforts in preventive, diagnostic, curative, and prognostic strategies for diseases associated with tobacco use in smokers and smokeless tobacco users could incorporate the oral microbiome.

Analysing Complex Oral Protein Samples: Complete Workflow and Case Analysis of Salivary Pellicles

Studies on small quantity, highly complex protein samples, such as salivary pellicle, have been enabled by recent major technological and analytical breakthroughs. Advances in mass spectrometry-based computational proteomics such as Multidimensional Protein Identification Technology have allowed precise identification and quantification of complex protein samples on a proteome-wide scale, which has enabled the determination of corresponding genes and cellular functions at the protein level. The latter was achieved via protein-protein interaction mapping with Gene Ontology annotation. In recent years, the application of these technologies has broken various barriers in small-quantity-complex-protein research such as salivary pellicle. This review provides a concise summary of contemporary proteomic techniques contributing to (1) increased complex protein (up to hundreds) identification using minute sample sizes (µg level), (2) precise protein quantification by advanced stable isotope labelling or label-free approaches and (3) the emerging concepts and techniques regarding computational integration, such as the Gene Ontology Consortium and protein-protein interaction mapping. The latter integrates the structural, genomic, and biological context of proteins and genes to predict protein interactions and functional connections in a given biological context. The same technological breakthroughs and computational integration concepts can also be applied to other low-volume oral protein complexes such as gingival crevicular or peri-implant sulcular fluids.

Interaction of storage medium and silver diamine fluoride on demineralized dentin

Objective

The effects of saliva on demineralized dentin and silver diamine fluoride (SDF) were investigated in vitro.

Methods

Dentin samples stored in deionized water (DIW), buffer solution (BS), basal medium mucin (BMM), and unstimulated whole saliva (UWS) were demineralized for 3 days and immersed in the same storage media. SDF as a 38 mass% solution was applied to the dentin samples for 3 minutes after they had been replaced in their respective medium. Surfaces were analyzed by scanning electron microscopy, energy-dispersive X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD).

Results

Scanning electron microscopy showed various surface deposits and coatings, including occlusion of dentinal tubules. DIW resulted in the thinnest coating, whereas BMM resulted in the thickest. EDX and XPS showed the formation of metallic silver and silver compounds in all four media, with the greatest formation in BS. XRD indicated that the main product was silver chloride except in DIW. Sulphur was found in BMM and UWS. EDX and XPS detected fluoride and XRD detected calcium fluoride and fluorohydroxyapatite in BS, BMM, and UWS.

Conclusion

The interaction between SDF and demineralized dentin was dependent upon the storage medium. BMM provided an outcome most similar to human saliva.

Salivary bacterial shifts in oral leukoplakia resemble the dysbiotic oral cancer bacteriome

Objective: While some oral carcinomas appear to arise de novo, others develop within long-standing conditions of the oral cavity that have malignant potential, now known as oral potentially malignant disorders (OPMDs). The oral bacteriome associated with OPMD has been studied to a lesser extent than that associated with oral cancer. To characterize the association in detail we compared the bacteriome in whole mouth fluid (WMF) in patients with oral leukoplakia, oral cancer and healthy controls. Methods: WMF bacteriome from 20 leukoplakia patients, 31 patients with oral cancer and 23 healthy controls were profiled using the Illumina MiSeq platform. Sequencing reads were processed using DADA2, and taxonomical classification was performed using the phylogenetic placement method. Sparse Partial Least Squares Regression Discriminant Analysis model was used to identify bacterial taxa that best discriminate the studied groups. Results: We found considerable overlap between the WMF bacteriome of leukoplakia and oral cancer while a clearer separation between healthy controls and the former two disorders was observed. Specifically, the separation was attributed to 14 taxa belonging to the genera Megaspheara, unclassified enterobacteria, Prevotella, Porphyromonas, Rothia and Salmonella, Streptococcus, and Fusobacterium. The most discriminative bacterial genera between leukoplakia and oral cancer were Megasphaera, unclassified Enterobacteriae, Salmonella and Prevotella. Conclusion: Oral bacteria may play a role in the early stages of oral carcinogenesis as a dysbiotic bacteriome is associated with oral leukoplakia and this resembles that of oral cancer more than healthy controls. Our findings may have implications for developing oral cancer prevention strategies targeting early microbial drivers of oral carcinogenesis.

In Vitro Salivary Protein Adsorption Profile on Titanium and Ceramic Surfaces and the Corresponding Putative Immunological Implications

Immune responses triggered by implant abutment surfaces contributed by surface-adsorbed proteins are critical in clinical implant integration. How material surface-adsorbed proteins relate to host immune responses remain unclear. This study aimed to profile and address the immunological roles of surface-adsorbed salivary proteins on conventional implant abutment materials. Standardized polished bocks (5 × 5 × 1 mm3) were prepared from titanium and feldspathic ceramic. Salivary acquired pellicle formed in vitro was examined by liquid chromatography-tandem mass spectrometry and gene ontology (GO) analysis to identify and characterize the adsorbed proteins. Out of 759 proteins identified from pooled saliva samples, 396 were found to be attached to the two materials tested-369 on titanium and 298 on ceramic, with 281 common to both. GO annotation of immune processes was undertaken to form a protein-protein interaction network, and 14 hub proteins (≥6 interaction partners) (coding genes: B2M, C3, CLU, DEFA1, HSP90AA1, HSP90AB1, LTF, PIGR, PSMA2, RAC1, RAP1A, S100A8, S100A9, and SLP1) were identified as the key proteins connecting multiple (6-9) immune processes. The results offered putative immunological prospects of implant abutment material surface-adsorbed salivary proteins, which could potentially underpin the dynamic nature of implant-mucosal/implant-microbial interactions.

Dysregulation of innate interferon signaling by Epstein-Barr virus tegument protein BGLF2

Epstein-Barr virus (EBV) successfully infects more than 90% of adults, causing lymphoid or epithelial malignancies such as lymphomas, nasopharyngeal and gastric carcinomas only in a small subset of infected people. EBV can switch between latency and lytic replication in B lymphocytes and epithelial cells. To maintain its life cycle, EBV has to develop mechanisms to evade host innate immune responses. In this study we identified EBV tegument protein BGLF2 as another viral modulator of JAK-STAT-dependent innate immune responses. BGLF2 interacted with STAT2 and promoted its degradation by enhancing K48-linked ubiquitination. BGLF2 also inhibited phosphorylation of JAK1 and STAT1, probably by recruiting a tyrosine phosphatase to these targets. As a result, BGLF2 suppressed ISRE-dependent transcription of interferon (IFN)-stimulated genes (ISGs) induced by type I IFNs. In addition, BGLF2 also exerted an inhibitory effect on type II and type III IFN signaling. Pre-treatment of host cells with IFN-β desensitized them for EBV primary infection and reactivation. Expression of BGLF2 in IFN-β-pre-treated cells reversed IFN-β-mediated inhibition and restored EBV infectivity. Thus, BGLF2 might subserve an IFN-antagonizing function in EBV lytic infection. Our findings reveal a novel EBV modulator of innate IFN response. Supported by HMRF 17160822, RGC C7027-16G and AoE/M-06/08.

The communal consultation video-Enhancing learning and broadening experience through observing dialogue

INTRODUCTION

This study presents a novel, student-centred, on-demand video learning modality that supports students as they transition from theory to clinical practice. Authentic, one-to-one teacher and student consultations have been video recorded and uploaded online for the peers and subsequent years of students to consume and learn from. This study describes the development and use of these communal consultation videos (CCVs), examines how students perceive this novel intervention and proposes supporting educational theory.

METHODS

A library of 28 CCVs has been archived online, to enable learning for students not present at the original staff consultation. A questionnaire was designed and administered to evaluate student perceptions of this novel learning intervention and administered to see how students used and perceived its benefit.

RESULTS

The CCV has proven to be popular, well received and valued by students. Students reported the videos were interactive, engaged them cognitively and supported them for assessments and in preparation for the clinical care of their own patients. Students also reported that watching the videos broadened their "clinical" experience of others cases that were different to their own.

CONCLUSION

This novel learning modality demonstrates new engaging learning opportunities for students and teachers that support students for assessments and clinical skill practice and afford observational clinical experience.

A qualitative analysis of students' perceptions of videos to support learning in a psychomotor skills course

INTRODUCTION

This qualitative study analysed students' experiences and perceptions about different types of videos in a psychomotor skills course, relating to clinical knowledge and skills and how they benefited learners in and out of the classroom.

METHODS

Subjects were recruited from 4th and 5th year dental undergraduate programme. The recruitment was terminated after 24 students participated since data saturation was reached. A semi-structured interview was conducted with each participating student, digitally recorded and transcribed verbatim. A thematic analysis was performed using an inductive approach to identify key themes.

RESULTS

Four key domains were identified from thematic analysis: functionality and access; learning and understanding; clinical skills preparation and performance and supplementary learning resources. Students perceived videos to be an important and vital learning tool relating to its on-demand access, control of functionality and use for particular needs that is not possible from textbooks or lectures. Video learning materials allows students to clarify knowledge, improve cognitive thinking and enhance revision of theoretical concepts and clinical skills. Two types of video were regarded as particularly useful as students reported being actively and cognitively engaged in the learning content and broadened their clinical experience. In addition, students reported mental preparation of clinical psychomotor skills using their own mental visualisation which enabled them to prepare for the clinical care of their patients.

CONCLUSION

This qualitative research supports the benefits of learning from videos in relation to convenience of access and functionality of the videos. In addition, it shows novel aspects to learning from videos that are more cognitively engaging and in mental preparation of clinical skills prior to patient care.

Does the use of amoxicillin/amoxicillin-clavulanic acid in third molar surgery reduce the risk of postoperative infection? A systematic review with meta-analysis

The objectives of this systematic review were to investigate the efficacy of amoxicillin/amoxicillin-clavulanic acid for reducing the risk of postoperative infection after third molar surgery and to evaluate the adverse outcomes in these patients, as well as in healthy volunteers. A systematic search of four databases was performed on May 26, 2017. Eleven studies qualified for the qualitative analysis and eight were found suitable for meta-analysis. The results suggest that both amoxicillin-clavulanic acid and amoxicillin significantly reduce the risk of infection after third molar extraction (overall relative risk (RR) 0.25, P<0.001). However, with the exclusion of randomized controlled trials with a split-mouth design (due to an inadequate crossover period after antibiotic treatment), only amoxicillin-clavulanic acid was found to be effective (RR 0.21, P<0.001). The risk of adverse effects was significantly higher in the amoxicillin-clavulanic acid group (RR=4.12, P=0.023) than in the amoxicillin group (RR 1.57, P=0.405). In conclusion, amoxicillin-clavulanic acid and amoxicillin may significantly reduce the risk of infection after third molar extraction. However, their use in third molar surgery should be viewed with caution, as recent clinical trials on healthy volunteers have shown evidence of the negative impact of amoxicillin use on bacterial diversity and antibiotic resistance.

Evaluation of peer-generated MCQs to assess and support learning in a problem-based learning programme

PURPOSE

Problem-based learning (PBL) students report uncertainty on the depth and breadth of learning required, and this is a significant stressor and challenge. Student-generated MCQ questions were trialled and evaluated as a way to support depth and breadth of learning.

METHODS

Students set MCQs relating to specified learning issues, and an analysis and evaluation of setting and answering the MCQs were performed. The Revised Study Process Questionnaire (R-SPQ-2F) and final written examination scores were correlated to question setting and answering. Students were asked to rate the impact of the MCQs on their learning in PBL.

RESULTS

A total of 147 questions were created and 2373 answered. Students reported challenges with setting questions, although these made them think more deeply and helped their learning and affirming their learning progress. MCQs authored indicated significant associations with Understanding, and examination scores were associated with MCQs authored. Students reported a moderate response to how the MCQs supported their depth and breadth of learning.

CONCLUSIONS

While MCQ setting was perceived as a useful learning exercise, students engaged to different levels and experienced challenges. Students were uncertain whether the MCQs helped clarify the depth and breadth of learning in PBL, as they were not clear whether the questions set by their peers were relevant to the required learning outcomes.

Challenges in the transition to clinical training in dentistry: An ADEE special interest group initial report

INTRODUCTION

Curricular integration in higher education has been widely supported in the educational literature. As a result, several health care and specifically dental curricula have evolved from compartmentalised disciplinary training to integrated modalities; however, in many courses, a pre-clinical-clinical watershed remains a barrier to integration in dental education. This article introduces a general description of the pre-clinical-clinical transition in dentistry according to the outcomes of the discussion held during the first working group session of the "Transition to Clinical Training" Special Interest Group during the 2016 annual meeting of the Association for Dental Education in Europe.

MATERIALS AND METHODS

An online questionnaire was made available before the meeting to survey the curricular characteristics of the participants' schools. During the meeting, a working session related to the pre-clinical-clinical transition occurred. Conclusions from the discussion are summarised in this article.

RESULTS

Fourteen dental schools from 12 countries participated in the online survey. The included programmes had an average duration of 5.3 years (SD = 0.48), with high school or the local equivalent as the required entrance level for dentistry. The hybrid curriculum was the leading curriculum design (n = 9) followed by competence-based curricula (n = 3), with patient treatment as the core of clinical training in every included programme.

CONCLUSION

The pre-clinical-clinical transition in dentistry is a recognisable matter in dental education that requires assessment and research to ease the management of a stage with relevant influence on educational outcomes. This article presents an initial framework for further research and educational intervention.

A randomized controlled trial of home bleaching of tetracycline-stained teeth

OBJECTIVES

To investigate the effectiveness of two home bleaching modalities on whitening of tetracycline-stained teeth (TST).

METHODS

A randomized controlled trial on the bleaching effect of 15% carbamide peroxide gel loaded in tray and 6.5% hydrogen peroxide strip in subjects with TST was performed. Eligible subjects were judged independently by two assessors, and randomly assigned into the tray or the strip group. Lightness (L*), redness (a*) and yellowness (b*) were measured with colorimeter at baseline, one, two and three months. Any adverse reaction associated with bleaching were also recorded. Overall colour changes (ΔE) were analysed by one-sample and independent t-test/Wilcoxon test at significance level α=0.05.

RESULT

Twelve and fourteen participants were allocated to the tray and the strip group respectively. Both groups experienced noticeable and significant L*a*b* improvement at the end of the trial in comparison to the baseline (p<0.05). Significant improvement was observed in the first month for the tray group (p<0.05) and in the first two months for the strip group (p<0.05). While greater lightness improvement was observed in the tray group over the strip group in the first month (p=0.02), the reverse was noticed in the second month (p=0.01). There was no difference between two groups at the end of this trial (p<0.05) and no significant adverse reactions were observed.

CONCLUSION

Over a three-month period, 6.0% hydrogen peroxide strip performed equally well as the 15% carbamide peroxide tray delivery system in TST.

CLINICAL SIGNIFICANCE

Home bleaching systems produce noticeable tooth whitening effect in subjects with tetracycline-stained teeth.

Elevated α-synuclein caused by SNCA gene triplication impairs neuronal differentiation and maturation in Parkinson's patient-derived induced pluripotent stem cells

We have assessed the impact of α-synuclein overexpression on the differentiation potential and phenotypic signatures of two neural-committed induced pluripotent stem cell lines derived from a Parkinson's disease patient with a triplication of the human SNCA genomic locus. In parallel, comparative studies were performed on two control lines derived from healthy individuals and lines generated from the patient iPS-derived neuroprogenitor lines infected with a lentivirus incorporating a small hairpin RNA to knock down the SNCA mRNA. The SNCA triplication lines exhibited a reduced capacity to differentiate into dopaminergic or GABAergic neurons and decreased neurite outgrowth and lower neuronal activity compared with control cultures. This delayed maturation phenotype was confirmed by gene expression profiling, which revealed a significant reduction in mRNA for genes implicated in neuronal differentiation such as delta-like homolog 1 (DLK1), gamma-aminobutyric acid type B receptor subunit 2 (GABABR2), nuclear receptor related 1 protein (NURR1), G-protein-regulated inward-rectifier potassium channel 2 (GIRK-2) and tyrosine hydroxylase (TH). The differentiated patient cells also demonstrated increased autophagic flux when stressed with chloroquine. We conclude that a two-fold overexpression of α-synuclein caused by a triplication of the SNCA gene is sufficient to impair the differentiation of neuronal progenitor cells, a finding with implications for adult neurogenesis and Parkinson's disease progression, particularly in the context of bioenergetic dysfunction.

Structural stability of posterior retainer design for resin-bonded prostheses: a 3D finite element study

The purpose of this in vitro study was to compare the stress distribution and natural frequency of different shape and thickness retainer designs for maxillary posterior resin-bonded prostheses using finite element (FE) method. A 3D FE model of a three unit posterior resin-bonded prosthesis analysis model was generated. Three different shaped retainer designs, viz. C-shaped (three axial surface wraparounds), D-shaped (three axial surface wraparounds with central groove) and O-shaped (360° wraparounds), and three different thicknesses, viz., 0.4, 0.8, and 1.2 mm, resin-bonded prostheses were used in this study. The resin-bonded prosthesis analysis model was imported into an FE analysis software (ANSYS 10.0, ANSYS, USA) and attribution of material properties. The nodes at the bottom surface of the roots were assigned fixed zero displacement in the three spatial dimensions. A simulated angle of 45° loading of a 100 N force was applied to the node of the pontic lingual cusp surface. The stress distributions and corresponding natural frequencies were analyzed and resolved. The C-shaped retainer for 0.4 mm thickness recorded the greatest von Mises stresses of 71.4 MPa for all three groups. C-shaped, D-shaped and O-shaped retainer presented natural frequencies 3,988, 7,754, and 10,494 Hz, respectively. D-shaped retainer and O-shaped retainer increased natural frequencies and structural rigidity over the traditional C-shaped retainer. The maximum von Mises stresses values of the remaining tooth and prosthesis decreased with greater retainer thickness. D-shaped retainer and O-shaped retainer increased natural frequencies and structural rigidity over the traditional C-shaped retainer.

Journal-based learning, a new learning experience building on PBL at HKU

OBJECTIVE

To evaluate the effectiveness of a new journal-based learning (JBL) programme designed to equip students with skills necessary to understand dental research publications, thereby preparing them for continuing professional development.

MATERIALS AND METHODS

A baseline evaluation of knowledge relating to key research terms was conducted on 52 final-year BDS students. 11 weekly seminars were conducted from 8 clinical disciplines driven by a reading list of 2-5 journal articles along with a series of 'guidance' questions relating to research terms and content knowledge aspects of each paper to focus their reading and learning. Seminars were facilitated by discipline experts with supporting notes. An exit test based on research process and terminologies for the programme was conducted with 4 repeated questions from the baseline assessment. A systematic marking scheme was used and the results analysed. A focus group was run to collect feedback regarding students' views and experiences on the JBL experience.

FINDINGS

Students showed significant improvements over the baseline score. The mean score rose from 3.5 to 11.5 in the repeated questions (P < 0.001). The focus group revealed that students had learnt new information about journal classification, evidence level determination, new research terms and the structure of research papers. From the first 4 years of PBL, students recognized the importance of learning from research papers since year 1. However, JBL gave them a deeper understanding of research and the development of critical appraisal skills.

IMPLICATIONS

JBL provided final-year students the opportunity to learn significantly more about dental research, terminologies, paper structure, critical analysis and content knowledge through active-learning small group seminars.

Self-perceived preparedness for dental practice amongst graduates of The University of Hong Kong's integrated PBL dental curriculum

OBJECTIVES

To determine how prepared for dental practice graduates from the integrated problem-based learning (PBL) dental undergraduate curriculum at The University of Hong Kong (HKU) perceive themselves to be and to identify factors associated with self-perceived preparedness.

MATERIALS AND METHODS

A postal questionnaire was sent to five cohorts of dentists who had graduated from HKU's integrated PBL curriculum between 2004 and 2008. Using a 4-point Likert scale, the questionnaire assessed the self-perceived level of preparedness in 59 competencies grouped in nine domains. Responses were dichotomised into 'poorly prepared' and 'well prepared'.

RESULTS

The response rate was 66% (159/241). The mean proportion (±standard deviation) of respondents indicating well-preparedness was 72.0±15.1% overall, and for each domain was as follows: general patient management, 93.1±12.1%; practice management, 81.0±22.2%; periodontology and dental public health, 73.5±19.3%; conservative dentistry, 92.5±13.1%; oral rehabilitation, 62.8±24.0%; orthodontics, 23.0±32.9%; managing children and special-needs patients, 64.8±28.9%; oral and maxillofacial surgery, 52.2±25.2%; and drug and emergency management, 84.7±22.6%. The odds of self-perceived well-preparedness were increased for cohorts graduating in 2004 and 2005 and graduates working in a non-solo dental practice.

CONCLUSIONS

Dental graduates of HKU's integrated PBL curriculum felt well prepared for the most fundamental aspects of dental practice. However, apparent deficiencies of training in orthodontics and oral and maxillofacial surgery will need to be addressed by continuing education, postgraduate training and planning for the new 6-year undergraduate curriculum in 2012.

Assessment of the use of problem-orientated, small-group discussion for learning of a fixed prosthodontic, simulation laboratory course

AIM

To evaluate a simulation laboratory course that used student-centred small-group problem-orientated discussion activities as the main medium of instruction.

METHODS

A structured questionnaire using a six-point Likert scale with 30 statements relating to a fixed prosthodontics course was distributed to 4th-year and 5th-year students who had completed the course.

RESULTS

A 93% response rate was achieved for both years with a mean score for the 4th-year being 94.2 (+/- 13.7) and the 5th-year 107.5 (+/-16.9). The differences between the scores of both years are highly significant (P = 0.0006) indicating that the 5th-year were more favourable about the course and learning approach used. Consistency and reliability of the questionnaire was judged reliable according to Cronbach's alpha (4th-year = 0.7, 5th-year = 0.83). Many aspects of the small-group student-centred activities were highly valued by students however, students expressed a preference for learning and interacting with teachers than colleagues.

CONCLUSION

Small-group student-centred learning activities were reported as creating an active, safe learning environment with beneficial opportunities for peer-peer interaction such as questioning, teaching and learning from students. However, students expressed a preference for teacher-centred information dissemination and activities. An understanding of the rationale of student dependence to teacher-centred learning may allow improved modifications in a student-centred learning environment.

The minimum inhibitory concentration of oral antibacterial agents against cariogenic organisms

The minimum inhibitory concentrations (MIC) of eight common dental antibacterial agents against three genera of bacteria which have been implicated in dentine caries, namely streptococci, lactobacilli and actinomycetes were investigated. The ultimate aim was to determine the most appropriate antibacterial agent which could be added to dental restorative materials for filling cavities where there was residual dentine caries. The antibacterial agents tested were chlorhexidine diacetate, chlorhexidine dihydrochloride, chlorhexidine gluconate, benzalkonium chloride, cetrimide, cetylpyridinium chloride, thymol and sodium hypochlorite. Thymol and sodium hypochlorite did not inhibit microbial growth at any of the concentrations tested. For the active antibacterial agents tested the MIC values against lactobacilli and streptococci were 0.25 microg/ml to 8.0 microg/ml and for actinomycetes 0.125 to 8.0 microg/ml. These results illustrate the wide spectrum of sensitivity of caries associated bacteria against dental antibacterial agents. From the MIC values alone, it is difficult to recommend which of the active antibacterial agents would be most effective in eliminating cariogenic organisms.

Fractional inhibitory concentration index of combinations of antibacterial agents against cariogenic organisms

OBJECTIVES

To examine the inhibitory effects between paired combinations of four antibacterial agents that have been investigated in dentistry against six bacteria associated with dentinal caries.

METHODS

The antibacterial agents tested were: chlorhexidine dihydrochloride, benzalkonium chloride, cetrimide and cetylpyridinium chloride. Two organisms each belonging to Streptococcus, Lactobacillus and Actinomyces species were evaluated against these agents. A checkerboard microtitration method was used to determine the minimum inhibitory concentration and fractionary inhibitory concentration (FIC) and summation operator FIC index of the paired combinations of antibacterial agents against the six species of bacteria. Appropriate controls were included. The summation operator FIC index was then used to determine if synergy, antagonism, or indifference occurred as a result of interactions between the antibacterial agents and the test organisms.

RESULTS

The data from a total of 295 test results were evaluated. Using summation operator FIC values for synergy as < or = 0.5 and antagonism as > 4.0 as recommended by The American Society for Microbiology, no significant synergistic or antagonistic interactions were observed between the paired antibacterial agents when tested against selected organisms. However, a tendency for an additive antibacterial effect was observed with approximately a third of the test results. Nonetheless, no combination of antibacterial agents appeared to be superior to any other.

CONCLUSIONS

According to these in vitro results, there appears to be no beneficial effect of combining the antibacterial agents against the individual cariogenic micro-organisms selected. However, it may be beneficial to use combined antibacterial agents that have a broader range of activity against an ecosystem of bacteria than using individual agents.

Two-unit cantilevered resin-bonded fixed partial dentures--a retrospective, preliminary clinical investigation

PURPOSE

The aim of this study was to retrospectively evaluate the clinical retention and abutment movement of 2-unit cantilevered resin-bonded fixed partial dentures (FPD) that were inserted at Prince Philip Dental Hospital in Hong Kong.

MATERIALS AND METHODS

Of 45 patients who were identified from a hospital computer search after receiving a 2-unit cantilevered resin-bonded FPD, 31 were clinically examined (33 FPDs). For each patient the following data were recorded: gender, age, cementation date, endodontic treatment if performed, bone support, tooth mobility, and FPD tipping or drifting. Data about any debonds with subsequent treatment and patient satisfaction on a 10-point scale were also recorded.

RESULTS

The mean service life for the 33 prostheses was 30 +/- 18 months, with a range of 72 days to 67 months. One prosthesis debonded, resulting in a clinical retention rate of 97%. No rotation, drifting, or tipping was observed for any of the prostheses during the short period of this study.

CONCLUSION

Two-unit cantilevered resin-bonded FPDs are successful in the short term, but further research is required to determine if they offer a viable alternative to fixed-fixed resin-bonded FPD designs.

Embedded problem-based learning of a clinical subject

A problem-based learning approach was used for the 'teaching' of a fourth-year bridge course in an attempt to improve student learning and academic performance in the clinical environment. The introduction of problem-based learning requires careful planning as to the desired educational objectives and design.