|Year : 2021 | Volume
| Issue : 1 | Page : 31-35
Do didactics improve clinical skills: A retrospective educational study
Poorya Jalali, Gerald N Glickman, Mikhail Umorin
Department of Endodontics, Texas A&M University College of Dentistry, Dallas, TX, USA
|Date of Submission||16-Mar-2020|
|Date of Decision||16-May-2020|
|Date of Acceptance||24-May-2020|
|Date of Web Publication||09-Jan-2021|
Dr. Poorya Jalali
Department of Endodontics, Texas A&M University College of Dentistry, 3302 Gaston Ave, Dallas, TX 75246
Source of Support: None, Conflict of Interest: None
Introduction: As predoctoral dental students navigate through the dental curriculum, the knowledge of clinical dentistry is progressively gained from didactic lecture courses. The goal of this study was to evaluate whether there is an association between endodontic didactic knowledge and endodontic preclinical skills.
Methods: The study utilized the existing preclinical endodontic assessments of 2nd-year dental students (105 students). Using ExamSoft, the nonclinical questions (e.g., microbiology and pulp biology) were excluded from the final didactic assessment, and a new didactic grade was calculated and assigned to each student. Each endodontic skill (access preparation, instrumentation and obturation, and combined) was matched with corresponding clinically related questions in the didactic assessment. For each student, the matched didactic grade was weighted against the practical grade using Kendall's τ correlation coefficient. To determine the effect of each predictor variable (didactic score and gender), an ordinal logistic regression was used.
Results: For all portions of the examination, the correlation between preclinical and didactic grades was significant, P < 0.05, but weak. Regression analysis showed that the didactic grade coefficient was significant for access, instrumentation and obturation, and combined portions of the examination. The student's gender coefficient was not significant for any portion of the examination.
Conclusion: Only a weak association was found between didactic performance and preclinical skills. Lectures on clinical topics should be improved and sequenced accordingly to better link the theory of endodontic technique to the hands-on simulation laboratory.
Clinical skills, dental education, didactics, endodontics, motor skills
|How to cite this article:|
Jalali P, Glickman GN, Umorin M. Do didactics improve clinical skills: A retrospective educational study. Saudi Endod J 2021;11:31-5
| Introduction|| |
Endodontics is the art of clinical skills combined with theoretical knowledge, and clinicians have to perform well in both areas to be effective.,, The theoretical component includes concepts such as biology, anatomy, diagnosis, pharmacology, and endodontic technique theory. On the other hand, the clinical component is the real-time application of endodontic technique theory into practice. The general skills for the clinical component of endodontics are patient management, communication, cognitive assimilation, time management, and fine motor skills. Although these two components of endodontics are taught and assessed with different methods in the curriculum, they are interdependent and of equal importance in endodontic education.
As predoctoral dental students navigate through the dental curriculum, the knowledge of clinical endodontics is progressively gained via didactic lecture courses. Before a skill is mastered in a hands-on simulation laboratory, didactic content related to the respective skill is typically required. Thus, by teaching the “theory” of endodontics, lectures are intended to assist dental students with their preclinical skills. To date, there is no study in the literature that has demonstrated an association between endodontic didactic grades and preclinical technique skills. Thus, the goal of this study was to evaluate whether there was an association between endodontic didactic knowledge and endodontic preclinical skills.
| Methods|| |
The study protocol (#2017-0382) was reviewed and granted exempt status by the Texas A&M University Institutional Review Board. The study population was compromised of students from the Texas A&M College of Dentistry graduating class of 2019 (n = 105). In this study, the assessments of the endodontic didactic course and endodontic laboratory course in 2017 were used. The endodontic didactic course was an introduction to the theory and practice of endodontics, and it included the fundamental principles for the treatment of pulpal and periapical disease. This course consisted of 14 1-h-long live lectures and 1 webcast lecture. The simulation laboratory course, through the use of acrylic teeth and extracted teeth, allowed the students to apply principles and concepts learned in the lecture course. This course consisted of 12 laboratory sessions, in which a short 20-min laboratory demonstration precedes each laboratory exercise. This course, combined with the endodontic didactic course, prepared students to provide clinical endodontic treatment.
A portion of the assessment for the didactic course was a midterm electronic examination consisting of 40 multiple-choice questions. The midterm didactic examination covered all the lectures that were given within a 6-week period before the examination. Test materials came from lectures, handouts, and reading materials covering the following topics: tooth morphology and anatomy of the root canal system, access cavity preparation, working length determination, cleaning and shaping of the root canal system, obturation of the root canal system, instruments and materials, pulp and periapical biology, and microbiology. All the lectures and laboratory demonstrations were given by either the director or co-director of the course. In order to investigate the impact of endodontic technique lectures on laboratory skills using ExamSoft (ExamSoft Worldwide, Inc., Dallas, TX, US), the nonclinical questions (i.e., microbiology and pulp biology) were redacted from the didactic assessment leaving 25 questions deemed relevant to the endodontic treatment. A new didactic grade was calculated and assigned to each student. Thus, due to relatively wide potential range of the grades, 0–25, the didactic grade was considered a continuous independent variable.
The updated didactic grades were compared against the grades of the midterm practical examination, which was taken 2 weeks following the didactic midterm examination. The midterm practical examination was part of the competency assessment for the laboratory course, in which students completed nonsurgical root canal treatment on a simulated acrylic maxillary central incisor. The examination consisted of complete endodontic treatment, i.e., access opening, cleaning and shaping with crown-down technique using a reciprocating instrumentation system, and obturation with synchronized hydraulic obturation technique. The examination was a manikin-based examination, and the students were required to adhere to infection control guidelines including the use of rubber dam. After the completion of examination, each case was graded independently by two endodontic faculties, and the graders were blinded to each other assessments. In addition, a code was assigned to each student; therefore, the evaluators were blinded to the students' names. Each endodontic skill (1. access cavity preparation and 2. instrumentation and obturation) was graded separately from a scale of 0–4, with 0 being very poor and 4 being excellent. Therefore, each faculty assigned two grades to each case and the final grade was calculated by averaging the grades of the two faculties. A disagreement of more than one grade separation for each skill was solved by consensus after consulting a third examiner. Thus, the practical grade was an ordinal dependent variable.
Finally, the didactic questions were categorized into two groups based on their relevance to each preclinical skill and were weighted against them. Therefore, average didactic grades for the topics “Tooth morphology and anatomy of the root canal system” and “Access cavity preparation” (7 questions) were weighted against laboratory “Access cavity preparation” grade. Additional, average grades for the topics “Tooth morphology and anatomy of the root canal system,” “Working length determination,” “Cleaning and shaping of the root canal system,” “Obturation of the root canal system,” and “Instruments and materials” (21 questions) were weighted against laboratory “instrumentation and obturation” grade.
[Table 1] lists the subtopics of the didactic examination that corresponded to each portion of the practical examination.
|Table 1: Partial Kendall's tau correlation coefficients between practical and didactic grades when controlling for variation in student's sex and their statistical significance for access, instrumentation and obturation, and combined portions of the examination|
Click here to view
The strength of association between students' performance on the didactic and practical examinations was assessed using a partial correlation coefficient to control for variability in student's gender. Analysis was performed in the R statistical software environment using ppcor software package.
To determine the effect of each predictor variable: didactic examination score and student's gender, on the corresponding practical examination score (separately for access, instrumentation and obturation, or combined portions), an ordinal logistic regression model using the two predictors was fit to the student examination data. Analysis was performed in the R statistical software environment (Foundation for Statistical Computing, Vienna, Austria) using VGAM software package.,
The level of significance adopted was 5% (P < .05).
| Results|| |
Partial Kendall's tau coefficients when eliminating the effect of sex and their statistical significance for different portions of the examination are presented in [Table 1].
For all portions of the examination, the correlation between preclinical and didactic grades was significant, P < 0.05, but weak. The strongest correlation was observed for the combined examination, where the partial correlation was 0.3, thus accounting for 9% of grade variability.
The results of fitting the proportional odds model using didactic examination grade and students' gender as predictors for each of the portions of the practical examination: access, instrumentation, and obturation, or combined, are presented in [Table 2]. The didactic grade coefficient was significant for access, instrumentation and obturation, and combined portions of the examination. The significance of the coefficient could not be calculated for the instrumentation and obturation portion due to the structure of the data. The student's gender coefficient was not significant for any portion of the examination.
|Table 2: Coefficients and their statistics from fitting the proportional odds model using didactic examination grade and students gender as predictors for the access, instrumentation and obturation portions, and the combined examination|
Click here to view
| Discussion|| |
The motor skills learning theory by Fitts and Posner identifies 3 distinct phases, which are widely accepted in the medical literature. These 3 overlapping phases involved in the learning of any motor skill: cognitive, associative, and autonomous.,, During the initial stage (cognitive stage), the student focuses on the cognitive component of the procedure, and the task is carried out in discrete steps. For example, when a student learns how to perform a nonsurgical root canal treatment, the student will focus on how to hold the file or a handpiece, and how to control the working length during instrumentation based on the information he/she gets from the radiograph. Each of these steps requires concentration, and with practice and feedback from the teacher, the student moves to the associative stage in which knowledge is integrated into motor behavior, and therefore, less concentration is required to finish the task. With consistent practice, the student may reach the final stage where the performance becomes autonomous, and the task can be completed appropriately even when concentrating on other aspects of the task, such as communication with the patient. It would be reasonable to assume that, during the preclinical course, dental students may perform within the first two phases. In addition, it would not be far from the truth to assume that the technique theory learned during the lecture course (understanding the task) may have a positive effect on initial learning phases. For example, remembering the exact obturation protocol can improve the quality of root canal filling, or knowledge in root canal anatomy (e.g., location of the pulp horns) can improve student's ability to perform an endodontic access.
In general, the effect of didactic knowledge on clinical skills has not been fully investigated in dentistry, and the studies about a possible relationship between the two are scarce in literature. Using a computerized assessment in this course gave us a unique opportunity to match each endodontic skill with its corresponding clinically related questions in the didactic assessment. With this approach, endodontic skill was broken into its component parts, and the effect of each didactic topic was assessed on its clinical target skill. In this study, the correlation coefficients between the practical and didactic performances were rather weak, even though significant [Table 1]. Pearson coefficients (not shown) were of similar magnitude. This indicates that student's performance on the laboratory test was not related to the performance on the didactic examination. The grades on the access portion of the examination were more variable than on the instrumentation and obturation portion. This can explain the lower and less significant correlation coefficient for the access portion of the examination. In turn, this may indicate that students who had more problems in this area could not be helped by the knowledge of the relevant theory. In addition, in this study, the significant effect of didactic grade may be a coincidence as higher performing students would simply perform high on either didactic or laboratory examination, or any other nonrelated examination, because of their innate abilities, more study time, greater commitment, etc. That is, they would perform better regardless of the knowledge from a preceding course. It would be worthwhile to see how the correlation and regression structure changes in relation to other courses or if the didactic and laboratory assessments are temporally switched.
Several studies have evaluated the impact of various predictors on the preclinical or clinical performance of dental students, and most of the predictors have shown only a weak correlation with preclinical skills.,,,,, To the best of our knowledge, there are no similar studies in the literature to compare the results with. However, few investigators have evaluated the correlation between academic performance and clinical proficiency. It has been shown that the National Board Dental Examination Part I and Dental Admission Test scores do not reliably predict dental students' clinical skills., In another study, the correlation between academic and practical performances for each course was evaluated, and no significant association was found for operative dentistry, prosthodontic, and orthodontic courses. Al-Asmar et al. in a study evaluating the grades of 3rd, 4th, and 5th-year dental students found only a weak-to-moderate correlation between didactic and practical performances. Afify et al. investigated the correlation between didactic and practical grades of dental students, and they did not find a correlation between academic performance and psychomotor skills. In addition, for complete denture prosthodontics, only a weak relationship between academic performance and practical skills was found. Therefore, in accordance with this study, most studies agree on weak or no association between didactic performance and clinical skills.
However, the effect of lectures on clinical performance should not be neglected. The fact that most of the studies have found a weak association between didactic performance and clinical skills could be due to a gap between the materials taught in didactic courses and the preclinical/clinical instruction. Hence, educators should attempt to tailor the clinical lectures accordingly to better link the theory of dentistry to clinical skills. In addition, the assessment of lecture courses should be improved to better reflect the clinical performance of students, for example, by incorporating digital objective structured clinical examination (OSCE) in didactic assessments. By integrating technology in education, educators can help students to build and demonstrate their critical thinking skills. For example, incorporating a computer-based OSCE using simulated endodontic scenarios may better reflect students' performance compared to a traditional multiple-choice examination. Further research is needed to evaluate the effect of these forms of critical-thinking assessments on clinical performance.
The findings of this study should be interpreted with caution, and they do not deny the effect of didactic knowledge on clinical abilities. The study could have benefitted by including a larger number of questions per topic. However, the large number of participants (105 students), partly, compensated for the low number of questions. The potential existence of confounding variables was another limitation of the study. One of the challenges in educational research is limiting the number of variables, and it may not be feasible to remove all the confounding variables. In this study, the effect of cofounding variables was minimized by including clinical lectures only, calibrated faculty, and a large sample size of students. Furthermore, it has to be emphasized that only some components of clinical endodontics were assessed in this study. In addition to fine motor skills and time management, clinical endodontics involves skills such as patient management and diagnosis, which were not assessed in the current study. Finally, the simulation examination used in this study lacked the complexity of real clinical scenarios that requires more cognitive ability. All these factors may have contributed to the findings of the study; therefore, the conclusion should not be generalized.
| Conclusion|| |
In this study, only a weak association was found between didactic performance and preclinical skills. Therefore, utmost importance should be given to the lectures on clinical topics in order to improve and tailor them accordingly to better link the theory of endodontic techniques to the hands-on simulation laboratory.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2]