Problem-based learning: effects on standard outcomes

Dental students at the Harvard School of Dental Medicine (HSDM) participate fully in the first two years of the curriculum with the Harvard Medical School (HMS) while also taking parallel dental classes. HSDM students were first exposed to problem-based learning (PBL) in 1987 when the "New Pathway" curriculum was introduced at HMS in the first two years of the medical school curriculum (the HSDM courses remained traditional lecture-based classes). In 1994, HSDM incorporated PBL into the first, second, and third (clinical year) year dental courses, and the curriculum shifted from a five-year curriculum to a four-year curriculum. The purpose of this study was to evaluate the effect of PBL and program length on measurable outcomes for dental education: NBDE Part I scores, attrition and graduation rates, and percentage of graduates entering postdoctoral training programs. This study was designed as a retrospective analysis of outcomes data from 1980 to 2002. Univariate linear regressions were computed for each measure against each outcome. Subsequent bivariate regression analyses revealed that the implementation of PBL has markedly affected NBDE Part I scores, graduation rates, attrition rates, entrance into postdoctoral plans, and percentage of graduates entering GPR/AEGD programs, while program length has had an effect on graduation rates, attrition rates, entrance into postdoctoral programs, and percentage of graduates entering GPR/AEGD programs. The findings of this report suggest that the implementation of PBL combined with a change in program length has been successful for all outcomes measured and that PBL alone has contributed to the rise in NBDE Part I scores among HSDM graduates.     

The impact of targeted shortened preclinical exercises on student perceptions and outcomes

The Harvard School of Dental Medicine (HSDM) introduced problem-based learning (PBL) into the dental curriculum in 1994 as a part of curriculum reform. During the reorganization, departments were consolidated, and courses were taught in an interdisciplinary fashion rather than in a discipline-based approach. The changes required a reduction in lecture and preclinical clock hours, which might have affected student performance and anxiety levels. The objectives of this study were to 1) compare the HSDM didactic and laboratory preclinical hours in Endodontics, Operative, and Prosthodontics before and after PBL implementation; 2) compare the HSDM didactic and laboratory preclinical hours in Endodontics, Operative, and Prosthodontics with other schools nationwide; 3) measure students' perceptions of their levels of stress and self-confidence at two time points during their preclinical and clinical years; 4) investigate the correlation between the number of preclinical hours and the students' stress level and self-confidence; and 5) evaluate the impact of shortened preclinical hours on the performance of HSDM students on the National Board Dental Examination Parts I and II. A survey regarding the students' level of stress, self-confidence, and preparation to treat patients during preclinical laboratory exercises was distributed to the HSDM classes of 2005 and 2006 (n=70). The HSDM preclinical curriculum hours were compared to national data as reported by the American Dental Association (ADA). Cross-tabulations were constructed, and the Fisher's exact test was conducted to examine the relationships between the variables. We found that HSDM preclinical hours in Endodontics, Operative, and Prosthodontics were significantly lower than at other schools. During the preclinical exercises, the Prosthodontics preclinical exercises were found to be the most stressful and provided the lowest self-confidence in treating patients as compared to the other preclinical subject areas. HSDM students' scores on the National Board Part I and II examinations continue to be among the highest in the nation and have not been affected by the change in curriculum. We conclude that the change in HSDM's curriculum that resulted in targeted, shorter preclinical exercises has not affected clinical and didactic outcomes, but may have affected the anxiety that students feel when entering the clinic.     

Association Between National Board Dental Examination Part II Scores and Comprehensive Examinations at Harvard School of Dental Medicine

Harvard School of Dental Medicine (HSDM) uses a hybrid problem-based approach to teaching in the predoctoral program. The objective structured clinical examination (OSCE) is a formative examination designed to assess the performance of students in the problem-based learning (PBL) curriculum. At HSDM three comprehensive examinations with OSCE components are administered during the third and fourth years of clinical training. The National Board Dental Examination (NBDE) Part II is taken in the final year of the predoctoral program. This study examines the association between the NBDE Part II and the comprehensive exams held at HSDM. Predoctoral students from the HSDM classes of 2005 and 2006 were included in this study. The outcome variable of interest was the scores obtained by students in the NBDE Part II, and the main independent variable of interest was the performance of students in the comprehensive exams (honors, pass, make-up exam to pass). The Mann-Whitney U-test was used to examine the association between the grades obtained in the each of the three comprehensive exams and the NBDE Part II scores. Multivariable linear regression analysis was also used to examine the association between the NBDE Part II scores and the comprehensive exam grades. The effect of potential confounding factors including age, sex, and race/ethnicity was adjusted. The results suggest that students who performed well in the comprehensive exams performed better on the NBDE Part II, even after adjusting for confounding factors. Future studies will examine the long-term impact of PBL on postdoctoral plans and career choices.     

Problem-based learning at the Harvard School of Dental Medicine: self-assessment of performance in postdoctoral training

Problem-based learning (PBL) was implemented into the dental curriculum at the Harvard School of Dental Medicine (HSDM) in 1994 with an expectation that this pedagogy would enhance students' critical thinking and communication skills as well as general professional competencies. Previous studies have described several aspects of the outcome of PBL curricula at the predoctoral level. However, there is no information available on the perceptions and performance of PBL graduates during their postdoctoral training in dentistry. The purpose of this study was to evaluate the effect of PBL methodology on the performance of HSDM graduates during their postdoctoral training in comparison with their non-HSDM (traditional) co-residents. Surveys containing traditional knowledge-based criteria, preclinical and clinical criteria, and PBL criteria were sent to HSDM graduates from the classes of 2002 through 2004 who were in postgraduate training programs. The HSDM and traditional graduates were asked to evaluate and compare their performance in selected areas with those of their co-residents from either a PBL curriculum or a traditional curriculum. The directors of each program were also asked to assess HSDM graduates relative to other graduates in the program based on the same aspects. Overall, HSDM graduates rated themselves more highly than non-HSDM graduates on all competencies. No significant difference between HSDM and non-HSDM responses was found in general dental knowledge, specialty specific knowledge, preclinical skills, clinical skills, communication with staff, and patient education, whereas significant differences (p<0.05) were found for communication with patients, critical thinking, independent learning, performance in small group settings, self-assessment, and teamwork. The data obtained from the program directors revealed corresponding results. The HSDM graduates' capacity for independent learning was rated as "excellent" by 65.31 percent of the directors and 80.95 percent of the HSDM graduates themselves. These findings suggest that the performance of HSDM graduates during their postdoctoral training met expectations and were similar to non-HSDM graduates for traditional residency program competencies. However, the PBL training appears to provide HSDM graduates with enhanced abilities in independent learning, communication, and cooperation skills.     

Students' Perceptions of Prosthodontics in a PBL Hybrid Curriculum

Purpose: A survey was distributed to the Harvard School of Dental Medicine (HSDM) predoctoral student classes of 2005 and 2006 to assess their perceptions regarding preclinical prosthodontics laboratory exercises. Prosthodontics curriculum clock hours, prosthodontics teaching participation, and plans for specialization were also analyzed. We hypothesized that reduced hours and perceived stress in the prosthodontics curriculum might impact students' choice of specialty at HSDM
Materials and Methods: HSDM preclinical prosthodontics clock hours were compared with national means from published data. A survey was distributed to the HSDM classes of 2005 and 2006 (n = 70) at the end of their preclinical prosthodontics laboratory exercises, prior to students seeing their first patient in the clinics.
Results: A 100% response rate was achieved. Results from this study show that HSDM preclinical prosthodontics clock hours are on average shorter than other schools. The majority of the students felt stressed during the laboratory exercises, and they felt they did not gain adequate knowledge from the lectures, resulting in low self-esteem (confidence) in treating patients in the clinic. Despite this perception, HSDM students do just as well, if not better, than other students, as judged by external and internal outcome measures. Graduate prosthodontics specialization is still a specialty of choice among the graduates when compared to national data.
Conclusions: The shortened preclinical didactic and laboratory exercises in prosthodontics at HSDM affect student anxiety, but not their didactic and clinical performances or their decisions in choosing their graduate program. Problem-based learning (PBL) tutorials help the students to integrate preclinical and clinical knowledge and skills in prosthodontics.     

Comparison of clinical productivity of senior dental students in a dental school teaching clinic versus community externship rotations

The aim of this study was to report on the clinical and monetary productivity of fourth-year dental students at community-based clinical sites and school-based clinics at the Harvard School of Dental Medicine (HSDM). This study included forty-seven students from the graduating classes of 2006, 2007, and 2008. These fourth-year students were required to spend twelve weeks at one of several participating community health centers throughout Massachusetts and New Hampshire. Students also treated their patient pool in the teaching practice at HSDM in the fourth year. The most common sixty American Dental Association procedure codes were compared, and variables were created by grouping them by specialty or type of service. HSDM dental students completed 8,365 procedures at an externship site during their community experience. An average of 178 procedures was completed per student, and mean revenue of $17,486 was produced. In comparison, the same students completed 3,640 procedures during an equal amount of time spent (normalized for this study) at the school teaching practice clinic, where each student completed an average of seventy-seven procedures and generated $16,802 in revenue. The results of this study show that fourth-year dental students at the community health centers, working under the supervision of adjunct faculty, completed more than double the number of procedures they did in the HSDM teaching practice clinic. However, the revenue generated was very similar at the two sites. In addition, the types of procedures performed by students at externship sites were simpler than the complex and specialized procedures performed at the HSDM clinic, which include fixed and removable prosthetics, periodontal surgery, and implantology.     

Factors associated with dental implant survival: a 4-year retrospective analysis

Background: Dental implants are a predictable treatment option for replacing missing teeth and have strong survival and success outcomes. However, previous research showed a wide array of potential risk factors that may have contributed to dental implant failures. The objectives of this study are to study if implant survival rates were affected by known risk factors and risk indicators that may have contributed to implant failures. The secondary outcome measures were whether the level of expertise of the periodontal residents affected success rates and how the rate of implant success at the Harvard School of Dental Medicine (HSDM) compared to published standards. Methods: A retrospective chart review of patients at the HSDM who had one of two types of rough‐surface implants (group A or B) placed by periodontology residents from 2003 to 2006 was performed. Demographic, health, and implant data were collected and analyzed by multimodel analyses to determine failure rates and any factors that may have increased the likelihood of an implant failure. Results: The study cohort included 341 dental implants. The odds ratio for an implant failure was most clearly elevated for diabetes (2.59 implant surface group B (7.84), and male groups (4.01). There was no significant difference regarding the resident experience. The success rate for HSDM periodontology residents was 96.48% during the 4‐year study period. Conclusions: This study demonstrates that implant success rates at HSDM fell within accepted published standards, confirmed previously identified risk factors for a failure, and potentially suggested that other acknowledged risk factors could be controlled for. Furthermore, the level of experience of the periodontology resident did not have an impact on survival outcomes.     

Preclinical restorative training

In conjunction with its problem-based learning curriculum, Harvard School of Dental Medicine (HSDM) developed a shortened preclinical restorative training curriculum. This study compared our curriculum with those in other dental schools and examined student reaction to it. Twenty-nine U.S. dental schools responded to a survey regarding the length of their preclinical course in Operative Dentistry. Nationally, preclinical courses ranged from 179 hours to 280 hours (mean +/- SEM = 193 +/- 9 hours; n = 29). In marked contrast, the new seventy-five-hour preclinical curriculum at Harvard was the lowest of any school, and significantly lower than the U.S. average (p < 0.01). In Harvard's previous curriculum, students spent 232 curriculum hours. Reactions of Harvard students to this compact preclinical curriculum were surveyed using a three-topic, three-category survey instrument. Results indicated that, prior to beginning clinical patient care, approximately 80 percent of students felt that the course was too short and 20 percent just right. Conversely, and retrospectively, after completing their dental school training, only 35 percent felt it was too short, and 65 percent felt it was just right. Retrospectively, in terms of clinical preparedness, 55 percent felt adequately prepared and 35 percent felt well prepared to treat their patients. No significant change was noted between Part II National Board scores following the change to the reduced curricula time. The average National Board Part II scores prior to initiating the new curriculum was 86.3, and afterwards, it was 86.2. Further, for the North East Regional Board, HSDM students in the past four years demonstrated a 98 percent overall success rate with 100 percent primary pass in the operative dentistry part of the examination. These results suggest that an abbreviated preclinical training is not only possible, but may make time available for training opportunities in other areas, such as aesthetic dental procedures and new biomaterials.     

Relationship between dental students' performance on standardized multiple-choice examinations and OSCEs

The purpose of this study was to examine the relationship among dental students' performance on the National Board Dental Examination (NBDE Parts I and II), comprehensive written multiple-choice question examinations (MCQ examinations), and objective structured clinical examinations (OSCEs) administered at the Harvard School of Dental Medicine (HSDM). Outcomes were measured during the third and fourth years at HSDM for the classes of 2006 and 2007. Three separate OSCE exams and two comprehensive MCQ examinations are administered during years 3 and 4 at HSDM per class. The study group was made up of sixty-two students (thirty-two females and thirty males). The average NBDE Parts I and II scores of the study population were 93.32 +/-4.02 and 84.63 +/-4.25, respectively, and were associated with outcomes on all three OSCE examinations (p相似文献   

Dental students' evaluation of 2 community-oriented PBL modules.

OBJECTIVES: To evaluate dental students' perception of 2 problem-based learning (PBL) modules in Dental Public Health implemented within the context of a traditional formal curriculum. METHODS: 2 dental community modules were implemented with an 8-month interval between them on the same group of dental undergraduates; the first in Term 2 and the second in Term 4 of a 5-year 15-term dental course. At the end of each module, a semi-structured questionnaire was administered to evaluate the introductory lecture, the fieldwork activity and the organisation of the modules. RESULTS: In both modules, students reported gaining insight into the subject matter, skills in teamwork, making presentations and collecting data. Some students in the 1st module needed more time to fulfil their learning objectives and had difficulty in collecting data. In the 2nd module, students reported that they lacked motivation because of the place of the module within their timetable. Opinions differed about groupwork. The content of and interest generated by fieldwork activity was rated more positively in the 2nd module than the 1st. Less positively rated in the 2nd module was the introductory lecture and module organisation. CONCLUSIONS: Implementing PBL within a traditional curriculum does not offer uniform outcomes for students. Optimum group size and adequate time are necessary if students are to benefit from PBL. A consistent and continuous PBL approach should be adopted rather than a sporadic one. Further research should establish the optimum balance between PBL and traditional approaches that would allow students to maximise the benefits of both and to identify those students best equipped to benefit from a 'mixed economy' of learning.     

Which factors influence students' selection of advanced graduate programs? One institution's experience

The reasons that students choose certain specialties may be integral to the quality of specialty programs and the future of those specialties. The Harvard School of Dental Medicine (HSDM) has a high percentage (87.6 percent) of students who enroll in postgraduate programs. The goals of this study were to establish a baseline of factors that affect postgraduate program selection at HSDM and to determine if there was a significant difference in factor selection by gender, relationship status, graduation year, or choice to specialize versus choice to pursue advanced training in general dentistry. As a pilot study, we asked HSDM graduates from the classes of 2005 to 2007 to rank the importance of forty-two factors in selecting a field of dentistry and a particular program or institution within a specialty. Overall, students felt that intellectual content, challenging diagnostic problems, and possessing a special skill or talent unique to a specialty were the most important factors in choosing a field of dentistry. Influence of family members in dentistry was ranked as least important. In choice of a certain program or institution within a given field, clinical training and philosophy of training were ranked most highly. Students felt that the opportunity to moonlight was least important. Significant differences (p<0.05) were found regarding gender, relationship status, and students who chose to specialize versus those pursuing advanced general dentistry training. No significant differences were found among the students in different graduating classes.     

Evaluation of student and faculty perceptions of the PBL curriculum at two dental schools from a student perspective: a cross-sectional survey

Abstract Problem‐based learning (PBL) research has primarily highlighted issues related to medical education and less evaluation has been reported from the field of dental education. Furthermore, literature reports tend to focus mainly on PBL from a pedagogic and curriculum constructional view and up to this date, studies from a student perspective are lacking. The aim of this study was to approach the evaluation of student and staff perceptions of PBL curricula from a student perspective at two separate schools: the Faculty of Odontology at the University of Malmö, Sweden and the dental school of the University of Southern California, School of Dentistry (USCSD), Los Angeles, CA, USA. The study was initiated and conducted by two of the authors, at the time senior students at the Faculty of Odontology in Malmö, Sweden. The study was comprised of a literature search, a 2 week field trip to USCSD, USA, survey distribution to students and faculty in both schools, analysis of the data and a written report for oral defence. The results from the survey were intended to provide feedback on student and faculty perceptions regarding the PBL curriculum. The results indicate a general student and faculty satisfaction with the PBL curriculum. Perhaps, surprisingly their perceptions did not differ significantly despite differences in geography, culture and implementation of PBL pedagogy.     

Students’ perception of a problem‐based learning scenario in dental nurse education

Background: In July 2008, The General Dental Council implemented mandatory registration for Dental Nurses in the United Kingdom, recognising them as legally responsible for patient care. As dentistry comes to terms with the impact registration has on dental nurses, sustained advances in the teaching of students in other healthcare disciplines demonstrate the way in which the role of pedagogy in dental nurse education has been underdeveloped. In an attempt to see dental nursing stand in line with other progressive healthcare professionals, the authors have implemented Problem‐Based Learning (PBL) into a dental nurse program in NHS Education for Scotland, Glasgow. Aim: The aim of the research is to assess the perceptions of dental nurse students with regard to participation in active learning. Materials and Methods: The study is facilitated by a short PBL package which offers introductory exposure to this method of learning. A qualitative approach has been taken to gather experiential data using a questionnaire. Thematic analysis took place to reveal emergent themes. Results: Analysis reveals that the participants found PBL to be an enjoyable experience that could be valuable in the acquisition of deep knowledge and improved patient care. The participants raised concerns with regard to confidence in their own knowledge acquisition in PBL sessions and highlighted a need for improved feedback. Discussion and conclusion: While the participants enjoyed the self directed nature of PBL, it is important to note that the need for facilitator guidance was considered imperative, especially where the students had little or no experience of PBL, as in this study.     

Using innovative group-work activities to enhance the problem-based learning experience for dental students

Problem-based learning (PBL) in medical and dental curricula is now well established, as such courses are seen to equip students with valuable transferable skills (e.g. problem-solving or team-working abilities), in addition to knowledge acquisition. However, it is often assumed that students improve in such skills without actually providing direct opportunity for practice, and without giving students feedback on their performance. 'The Manchester Dental Programme' (TMDP) was developed at The University of Manchester, UK as a 5-year, integrated enquiry-led curriculum. The existing PBL course was redesigned to include a unique, additional PBL session ('Session 4') that incorporated an activity for the group to complete, based on the subject material covered during student self-study. A summative mark was awarded for each activity that reflected the teamwork, organisational and overall capabilities of the groups. This paper describes the different types of activities developed for the Session 4 and presents an analysis of the perceptions of the students and staff involved. The student response to the Session 4 activities, obtained via questionnaires, was extremely positive, with the majority finding them fun, yet challenging, and 'worthwhile'. The activities were perceived to enhance subject understanding; develop students' problem-solving skills; allow the application of knowledge to new situations, and helped to identify gaps in knowledge to direct further study. Staff found the activities innovative and exciting learning tools for the students. The Session 4 activities described here are useful educational resources that could be adapted for other PBL courses in a wide variety of subject areas.     

The changing face of dental education: the impact of PBL.

The past decade has seen increasing demands for reform of dental education that would produce a graduate better equipped to work in the rapidly changing world of the twenty-first century. Among the most notable curriculum changes implemented in dental schools is a move toward Problem-Based Learning (PBL). PBL, in some form, has been a feature of medical education for several decades, but has only recently been introduced into dental schools. This paper discusses the rationale for the introduction of a PBL pedagogy into dental education, the modalities of PBL being introduced, and the implications of the introduction of PBL into dental schools. Matters related to implementation, faculty development, admissions, and assessment are addressed. Observations derived from a parallel-track dental PBL curriculum at the University of Southern California (USC) are presented and discussed. This program conforms to the Barrows (1998) concept of "authentic PBL" in that the program has no scheduled lectures and maintains a PBL pedagogy for all four years of the curriculum. The USC dental students working in the PBL curriculum have attained a high level of achievement on U.S. National Dental Boards (Part I) examinations, significantly superior to their peers working in a traditional lecture-based curriculum.     

Adding problem-based learning tutorials to a traditional lecture-based curriculum: a pilot study in a dental school

This article reports on the implementation of a problem-based learning (PBL) tutorial in our advanced program for second year students within an existing curriculum. The program was opened on the last 5 days of the summer vacation and students could volunteer to be part of the group. Students separated themselves into small groups by random sampling. The PBL tutorials were done during the first 3 days for medical problems according to our original scenarios (based on medical cases), and during the last 2 days, students made presentations of their learning outcomes, using information technology (IT) by themselves. Throughout this program, students were expected to engage in self-learning, except for a 1¹/₂-h group session with a tutor. Assessment was done by attendance at a group session and by portfolio analysis. Following the portfolio analysis, students identified the number of learning issues (group A, 26 ± 7 issues; group B, 20 ± 3 issues; group C, 21 ± 7 issues). Research, by questionnaire, revealed that 84% of the students were strongly interested in each scenario and 95% of the students felt familiar with each scenario. The levels of satisfaction with the tutor were different in the three groups. All of the students were comfortable in the discussion room and IT center. These results suggested that PBL tutorials are supported by the scenario, the tutor, and the location of the group session, as well as by self-learning. Moreover, one of the most important factors for a PBL tutorial that the student is ready for the free discussions and has enough time for individual self-learning.     

Does a case completion curriculum influence dental students' clinical productivity?

The purpose of this study was to evaluate the effects of a new clinical curriculum on dental student productivity as measured by number of procedures performed in the student teaching practice. Harvard School of Dental Medicine adopted a new clinical education model for the predoctoral program in summer 2009 based upon a Case Completion Curriculum (CCC) rather than a discipline-based numeric threshold system. The two study groups (threshold group and case completion group) consisted of students who graduated in 2009 and 2010. Clinical performance was assessed by clinical productivity across five major discipline areas: periodontics, operative dentistry, removable prosthodontics, fixed prosthodontics, and endodontics. The relationships between the two study groups with regard to number of procedures performed by category revealed that the case completion group performed a significantly higher number of operative and removable prosthodontic procedures, but fewer periodontal and endodontic procedures (p≤0.03). No statistically significant difference in number of procedures was observed with fixed prosthodontic procedures between the two groups. Clinical productivity as a result of redesigning the clinical component of the curriculum varied in selected disciplines. The CCC, in which the comprehensive management of the patient was the priority, contributed to achieving a patient-based comprehensive care practice.     

Providing support for problem-based learning in dentistry: the Manchester experience

The introduction of problem-based learning (PBL) into any programme demands a period of adjustment on the part of faculty. Similarly, students new to PBL take time to adapt to what is, for the majority of them, an unfamiliar mode of learning. At Manchester, closed loop PBL is used throughout the first and second years of the dental programme; the method is interdisciplinary; there are no subject boundaries. Dental students work in groups of between 10 and 15, facilitated by a tutor from the Department of Biological Sciences, to research topics and share information in a mutually supportive environment. Each week a different problem forms the focus for learning. In this paper, we seek to describe the measures introduced in response to student feedback collected via routine meetings with the senior tutor, after meetings with their academic or personal tutors and through discussion at the staff students' committee, which we at Manchester have taken to facilitate the process of adaptation to PBL. Changes have been made in the areas of recruitment, pre-admission interviewing, induction (development of an induction booklet and communication skills module) and tutorial support (overhaul of personal tutor system and introduction of peer-assisted study (PAS) and personal and academic development programmes (PADPs)). Feedback on these changes, gathered via the routes described above, has been positive and continues to be central to our processes of development in these areas. Although the various ways in which PBL has been implemented worldwide may place limits on the transferability of our methods, this paper serves to illustrate some of the means available to support students in the transition to self-directed learning. The latter is not only an essential component of PBL but also something we should be seeking to foster in all students, no matter what philosophy and method of course delivery are utilized.