Thomas Corne Postma

Developing clinical reasoning in the classroom - analysis of the 4C/ID-model.

OBJECTIVES The purpose of this study is to provide a theoretical rationale for the implementation of the four-component instructional design model for complex learning (4C/ID-model) at the University of Pretoria with the aim of systematically developing the clinical reasoning of undergraduate dental students in a classroom setting. METHODS Recent literature provides a rationale for the use of the 4C/ID-model to teach clinical reasoning in terms of four strategic teaching and learning needs: (i) the need for authenticity in the learning process; (ii) the need to manage cognitive load during the learning process; (iii) the need for repeated practice; (iv) a need for valid assessment, feedback and reflection. RESULTS AND DISCUSSION The literature review indicated that the 4C/ID-model makes provision for teaching and learning in an authentic context and proposes systematically structured methods that could be practically applied to manage cognitive load during repetitive exercises. The model also makes provision for cognitive feedback following assessment in order to eliminate misconceptions about content and to develop the cognitive strategies of the learner. CONCLUSIONS On the basis of the literature review above, it is recommended that the 4C/ID-model be considered as a basis for classroom teaching and learning to develop competence in clinical reasoning in undergraduate dental students, even at pre-clinical level. The model may also have an application in medical education.

Developing integrated clinical reasoning competencies in dental students using scaffolded case-based learning - empirical evidence.

INTRODUCTION This study provides empirical evidence of the development of integrated clinical reasoning in the discipline-based School of Dentistry, University of Pretoria, South Africa. Students were exposed to case-based learning in comprehensive patient care (CPC) in the preclinical year of study, scaffolded by means of the four-component instructional design model for complex learning. METHODS Progress test scores of third- to fifth-year dental students, who received case-based teaching and learning in the third year (2009-2011), were compared to the scores of preceding fourth- and fifth-year cohorts. These fourth- and fifth-year cohorts received content-based teaching concurrently with their clinical training in CPC. The progress test consisted of a complex case study and 32 MCQs on tracer conditions. Students had to gather the necessary information and had to make diagnostic and treatment-planning decisions. RESULTS Preclinical students who participated in the case-based teaching and learning achieved similar scores compared to final-year students who received lecture-based teaching and learning. Final-year students who participated in the case-based learning made three more correct clinical decisions per student, compared to those who received content-based teaching. Students struggled more with treatment-planning than with diagnostic decisions. CONCLUSION The scaffolded case-based learning appears to contribute to accurate clinical decisions when compared to lecture-based teaching. It is suggested that the development of integrated reasoning competencies starts as early as possible in a dental curriculum, perhaps even in the preclinical year of study. Treatment-planning should receive particular attention.

Self-regulation – the key to progress in clinical reasoning?

Background. In 2009 a new case-based instructional design was implemented during the preclinical year of study of the undergraduate dental curriculum of the University of Pretoria, South Africa. The objective of the educational intervention was to improve the development of clinical reasoning skills. To achieve this, systematic scaffolding, relevance, integration and problem-solving were actively promoted as part of teaching and learning. A student’s clinical reasoning was measured by a progress test containing 32 multiple choice questions (MCQs), formulated on a knowledge application level. In 2011 it became clear that some students showed progression while others did not. Objectives. This study was conducted to gauge the value of the case-based intervention with the aim of determining the need for further scaffolding and support, especially for non-progressing students. Methods. The 2011 BChD IV cohort (N=48) was identified for the study. Two semi-structured focus group discussions were conducted. Group 1 (n=8) consisted of students who progressed ≥9%, while group 2 (n=8) comprised students who did not progress to the same extent. Results. Both groups lauded the scaffolding that the case-based curriculum provided. Strategic thinking, goal orientation and self-regulation ability were identified in group 1. A lack of diligence, poor data-processing ability and a possible lack of interest were identified in group 2 students, who were unaware of learning opportunities. Conclusion. There is a need for early identification of students lacking self-regulated learning and for providing timely feedback and support to progressively develop their clinical reasoning skills.

Second-year dental students’ perceptions about a joint basic science curriculum

Background . Medical and dental students often participate in joint basic science curricula, such as the basic science curriculum at the University of Pretoria, South Africa. Reports from the USA and Australia, however, show that it may be problematic because joint basic science curricula are mostly tailored around the needs of the medical students only, which may lead to prejudice and marginalisation of dental students. There are no local studies to inform decision-making in this regard. Objectives. To determine whether dental students perceived the joint basic science curriculum at the University of Pretoria to be relevant to their needs and if they felt marginalised. Methods. Reflective essays with regard to the 2011 and 2012 second-year dental students’ perceptions of the first 2 years of study in the joint curriculum were qualitatively analysed using a thematic approach. Frequency distributions of the identified themes were also calculated. Results. Despite positive comments, the dental students perceived that the joint basic science curriculum at the University of Pretoria may not be relevant to their needs and that they are being marginalised in the teaching and learning processes. Conclusion . The current study highlights the need for improvements in the manner in which joint basic science curricula are being administered in order to foster interprofessional collaboration. Alternatively, dental and medical students should be separated to ensure that the educational objectives of basic science curricula are being met for minority groups, such as dental students.

Assessment of the anterior loop of the inferior alveolar nerve using reformatted computed tomography : a retrospective study

The anterior loop of the inferior alveolar nerve (IAN) is an important landmark in the anterior mandible that must be considered during the placement of dental implants. We measured the length and prevalence of loops of the IAN in 188 consecutive, dentate patients using reformatted computed tomography (CT). A total of 158/188 (84%) had at least one anterior loop; 111/188 (59%) had bilateral loops. The mean (SD) length of the loops in the third quadrant was 1.4 (0.7)mm; 95% CI 1.3 to 1.6; (range 0.3 - 4.0mm). The mean (SD) length of the loops in the fourth quadrant was 1.5 (0.9)mm; 95% CI 1.4 to 1.6; range 0.3 - 5.5mm. In total 42/188 (22%) had loops that were longer than 2mm in quadrants three and four. CT images that have been reformatted with specialised software may be useful to identify loops in the IAN, particularly when recent cone-beam CT images are not freely available. The prevalence of these loops is high while their length varies, which makes meticulous assessment necessary before the placement of implants.

The prevalence of second canals in the mesiobuccal root of maxillary molars: A cone beam computed tomography study

The aim of this study was to determine the prevalence of MB2 canals in permanent maxillary molars utilising CBCT; in patients attending a university hospital. A total of 200 patient scans, (100 female and 100 male patients), were enrolled in the study. In total, 800 teeth were analysed, and teeth with additional canals in their MB roots (MB2) were identified. First maxillary molar teeth exhibited the highest prevalence of MB2 canals, 92% and 87%, for teeth 16 and 26, respectively. Second maxillary molar teeth showed a lower prevalence of MB2 canals, 69% and 65%, for the 17 and 27, respectively. There were no associations of significance between the prevalence of MB2 canals and patient age or gender. Root morphology and anatomy of permanent maxillary first and second molar teeth was found to be highly variable. The prevalence of additional canals in the MB roots is a frequent finding which has previously been underreported.

The influence of storage media on early osseointegration of titanium implants

Introduction: Marketing of implants stored in different media other than air could improve implant wettability resulting in a favorable implant bone interface with subsequent optimized early osseointegration. The effect that the different storage media, such as saline, air and argon, have on the early osseointegration of plasma treated, titanium dental implants was investigated and was compared to conventional implants stored in air, in an ovine pelvis model. 96 implants were inserted in the iliac crests of four sheep and tested for osseointegration by comparing insertion torque values and removal torque values at 4 and 6 weeks postinsertion. Twelve implants were inserted in each ovine iliac crest (24 per sheep representing six implants from each experimental group). Saline demonstrated the highest increase in torque values with argon demonstrating a linear decrease. The average percentage gain for each of the storage media at 4 weeks were plasma/air = +2%, plasma/saline = +30.4%, air = +9.6% and plasma/argon = −30.4%. The results were only statistically significant for the saline group at 4 weeks and the argon group at 2 weeks. All storage media demonstrated an initial decrease in torque value of 14.25% at 2 weeks before a strong rise in torque value could be observed. Saline as a storage media has great potential for improving early osseointegration. An interesting observation made was that the majority of the dental implants tend to demonstrate an initial decrease in osseointegration before demonstrating a strong rise in torque values. Further studies are recommended for the periods of 6 and 8 weeks after implant placement. Context: Research protocol. Aims: The purpose of the study was to compare the early osseointegration potential of plasma-enhanced implants stored in different storage mediums, to conventional implant stored in air. Settings and Design: The experiment consisted out of a comparative in vivo pilot study in which the early osseointegration potential of implants stored in four different storage media was compared. These implants were inserted in the iliac crest of four sheep, and the degree of osseointegration of the different groups was compared at 2 and 4 weeks after insertion. The osseointegration potential of the implants was evaluated by measuring and documenting the insertion torque and comparing it to the removal torque values of each implant. Subjects and Methods: A total of 96 (n = 96) dental implants (3.75 mm in diameter and 10 mm in length), including 24 plasma-enhanced dental implants stored in air; 24 plasma-enhanced dental implants stored in argon; 24 plasma-enhanced dental implants stored in saline and 24 conventional dental implants stored in air; were inserted into the iliac crests of 4 sheep. The insertion torque values were measured and documented on insertion. Two sheep were euthanized after a period of 2 weeks postinsertion, and the maximum removal torque value of each implant was measured and documented. The remaining two sheep were euthanized at 4 weeks postinsertion and the maximum removal torque of each implant measured and documented. The torque values measured on insertion, after 2 weeks, and after 4 weeks postinsertion were then compared and used to determine the level of osseointegration as well as the potential for further osseointegration. Statistical Analysis Used: Comparative graphical analysis was performed. Significance was determinant at P < 0.05. Results: Saline demonstrated the highest increase in torque values with argon demonstrating a linear decrease. The average percentage gain for each of the storage media at 4 weeks were plasma/air = +2%, plasma/saline = +30.4%, air= +9.6%, and plasma/argon = −30.4%. The results were only statistically significant for the saline group at 4 weeks and the air group at 2 weeks. All storage media demonstrated an initial decrease in torque value of 14.25% at 2 weeks before a strong rise in torque value could be observed. Conclusion: Saline as a storage media has great potential for improving early osseointegration. The majority of the dental implants tend to demonstrate an initial decrease in osseointegration before demonstrating a strong rise in torque values. Further studies are recommended for periods of 6 and 8 weeks after implant placement.