Difficulty levels of extracted human teeth used for pre-clinical training in endodontics in an Australian dental school

A Novel Self-Assessment Method for Training Access Cavity on 3D Printed Endodontic Models

BACKGROUND

New technologies can facilitate the transition from pre-clinical to clinical settings. We investigate students' satisfaction with a novel learning method adopted in access cavity exercises.

METHODS

Students performed their access cavity on inexpensive, in-house 3D printed teeth. Their performances were evaluated by scanning the prepared teeth with an intraoral scanner and visualized using a mesh processing software. Then, the same software was used to align the tooth prepared by the student and the teacher's one for self-assessment purposes. Students were asked to answer a questionnaire about their experiences with this new learning method.

RESULTS

From the teacher's perspective, this novel learning approach was easy, straightforward and affordable. Overall, student feedback was positive: 73% found that access cavity assessment by scanning was more useful compared to a visual inspection under magnification and 57% reported that they had a better understanding of errors and mishaps. On the other hand, students pointed out that the material used to print teeth was too soft.

CONCLUSION

The use of in-house 3D printed teeth in pre-clinical training is a simple way to overcome some of the drawbacks associated with extracted teeth, such as limited availability, variability, cross-infection control, and ethical constraints. The use of intraoral scanners and mesh processing software could improve student self-assessment.

Comparative Evaluation of Hybrid 3D-Printed Models versus Cadaveric Animal Jaws: A Student's Perspective

Objective

To get a feedback from students participating in a skill enhancement course where a combination of a 3D-printed mandible with a natural tooth in place of the impacted tooth for surgical training is used and to compare it to an animal jaw model used for the same purpose.

Methods

41 participants were enrolled for the study, and extraction procedure was performed on both the bovine jaw and the 3D-printed mandible. Participants evaluated both models using a validated questionnaire to assess the anatomical and operative simulation and to compare its cost effectiveness.

Results

Overall significant differences between the two models were found in the student assessment. Whilst the animal jaw models achieved better results in the haptic feedback of the soft tissue, the 3D-printed models were regarded significantly more realistic with regard to the anatomical correctness, the degree of freedom of movement and the operative simulation.

Conclusion

The 3D-printed models presented a realistic alternative to cadaveric jaw models in the training of operational skills of dental surgeons. Whilst the 3D-printed models received positive feedback from students in a hands-on course, some aspects of the model leave room for improvement.

Effect of an endodontic e-learning application on students' performance during their first root canal treatment on real patients: a pilot study

BACKGROUND

E-learning has found its way into dental teaching in general and endodontic teaching in particular. The present study aimed to implement a newly developed multimedia learning application and assess its effect on students' first root canal treatment on real patients. With the COVID-19 outbreak, the application's performance was investigated during the pandemic.

METHODS

A total of 138 students in the initial clinical endodontic course participated in this study. The control group (n = 49) followed the traditional curriculum, including practice on artificial teeth and face-to-face teaching events. In addition to the traditional curriculum, test group 1 (n = 54) had access to an endodontic e-learning application containing videos demonstrating artificial teeth and patient cases. With the COVID-19 outbreak, test group 2 (n = 35) had no face-to-face teaching; however, endodontic patient treatments were included. The quality of students' first root canal treatment on real patients was compared using performance and radiographic assessment items. Statistical analysis was done using Kruskal-Wallis and chi-squared tests. Test groups received a questionnaire to assess the learning application. Test group 2 also completed a COVID-19-specific survey to measure students' perceptions of how the pandemic affected their endodontic education.

RESULTS

The results of endodontic treatments were significantly better for test group 1 (P < 0.001) and 2 (P < 0.001) than for the control group. Likewise, there were significantly fewer treatment errors in test group 1 (P < 0.001) and 2 (P < 0.001). No significant differences were found between test groups 1 and 2. Students of the test groups positively evaluated the e-learning application. Students of test group 2 expressed their fear of negative impacts on their course performance.

CONCLUSION

The e-learning application was well-received and seemed to improve endodontic education. The results imply that the quality of education may be maintained by implementing e-learning to compensate for face-to-face teaching. As no difference was found between online and face-to-face teaching, students' and lecturers' concerns that endodontic education is suffering because of the pandemic may be eased.

Determining the impact of stressors on students' clinical performance in endodontics

OBJECTIVES

This study aims to evaluate the impact of stress on the clinical performance of endodontics dental students.

METHOD

The study sample consists of 16 randomly selected fourth-year dental students who had completed pre-clinical activities stipulated in their curriculum. The distal canal of a plastic mandibular first molar is prepared on two separate occasions, first under normal conditions and then under stressful conditions. The preparation accuracy of the root canal and the time taken to complete the task area measured. Stress is assessed using subjective (State-Trait Anxiety Inventory and Perceived Stress Scale) and objective (heart rate) measures.

RESULTS

While the accuracy of the root canal preparation did not differ significantly between the normal and stressful conditions (p > 0.05, paired t-test), the completion time for the root canal preparation decreased significantly under stressful conditions (p < 0.05, paired t-test).

CONCLUSION

The findings of this study suggest that there is no association between the high levels of stress and the performance breakdown of root canal hand instrumentation skills. Students develop an adaptive response to stress, enabling them to improve their completion times and maintain their performance under stressful conditions. Future research should focus on learning methods that can contribute toward better outcomes, especially in stressful environments.

Effectiveness of photon-initiated photoacoustic streaming in root canal models with different diameters or tapers

Background

This study aimed to compare the use of photon-initiated photoacoustic streaming (PIPS) and conventional needle irrigation (CNI) in conjunction with different concentrations of sodium hypochlorite (NaOCl) to remove Enterococcus faecalis (E. faecalis) suspended bacteria and biofilms from root canal systems with different diameters or tapers.

Methods

Artificial root canal samples (n = 480) were randomly divided into three groups (n = 160/group). The canals were prepared to fit file sizes #10/.02, #25/.02, or #25/.06. The size #10/.02 group was incubated for seven days. The size #25/.02 or #25/.06 group was incubated for 2 days. A stable biological model of E. faecalis infection was established. The root canals were washed with distilled water or with 1%, 2%, or 5.25% NaOCl combined with CNI or PIPS. Bacterial suspensions and biofilms were assessed using an ATP assay kit and fluorescence microscopy. Image-Pro Plus was used to analyse the average fluorescence intensity to determine the most suitable root canal irrigation solution.

Results

In the CNI and PIPS groups, the ATP value of the 5.25% NaOCl subgroup was the lowest, followed by that of the 2% and 1% NaOCl subgroups. The ATP value of the distilled water subgroup was the highest (P < 0.05). When the root canal taper was 0.02, the ATP value of the #10/.02 + PIPS group was significantly lower than that of the #25/.02 + CNI group (P < 0.05). The average fluorescence intensity of the #10/.02 + PIPS group was lower than that of the #25/.02 + CNI group (P < 0.05). When the apical diameter was #25, the ATP value of the 0.02 taper in the PIPS group was lower than that of the 0.06 taper in the CNI group (P < 0.05), and the average fluorescence intensity of the 0.02 taper + PIPS group was lower than that of the 0.06 taper + CNI group (P < 0.05). PIPS combined with 2% and 5.25% NaOCl effectively improved the long-term antibacterial effect after irrigation and re-culture for 6 h.

Conclusions

Compared with CNI, PIPS has greater ability to remove bacteria in root canals with a small preparation diameter and a small taper. PIPS with 2% and 5.25% NaOCl exhibited superior antibacterial and bacteriostatic effects.

Suitability of different tooth replicas for endodontic training: perceptions and detection of common errors in the performance of postgraduate students

AIM

To compare the perceptions of students when using five different tooth replicas and to detect common errors in the performance of students that might be attributed to a specific type of tooth replica.

METHODOLOGY

Five groups (n = 10 each) of artificial first maxillary molars (DEPT, DRSK, Nissin, DENTALIKE and TrueTooth) were used. All 50 teeth were mounted individually in opaque containers, distributed in 10 packages containing a sample from each with an assigned random order for students to perform root canal treatments. Ten postgraduate students each performed a root canal treatment on the five replicas, in the assigned order, and completed a satisfaction questionnaire. Three trained and calibrated endodontic educators, each with more than 15 years of experience, evaluated their performance using a grading rubric and completed a questionnaire to detect common errors attributed to a specific tooth replica. Inter-rater reliability was calculated with the interclass correlation coefficient for both consistency and absolute agreement. A two-way related measures anova was used to assess the interaction amongst evaluators and tooth groups on the average scores of students. Post hoc T3 Dunnet was used to compare groups. The perceptions of students amongst groups were compared with chi-square and linear-by-linear association tests.

RESULTS

Inter-rater reliability was very high for both consistency (ICCC = 0.939; 95% confidence interval (CI) 0.902-0.964) and absolute agreement (ICCA = 0.940; 95% CI 0.904-0.965). No significant differences were found amongst the ratings of evaluators; however, students performed differently when using the various tooth replicas (P < 0.05). Overall, 60% of students preferred the DRSK replica for root canal treatment training purposes, followed by DENTALIKE (30%). The least preferred was TrueTooth (70% responses) due to its complex anatomy and poor resistance to instruments and heat pluggers. Evaluators detected several common errors in specific tooth replicas and preferred tooth replicas manufactured based on microCT scans of natural teeth.

CONCLUSIONS

Tooth replicas manufactured based on microCT scans of natural teeth (TrueTooth and DENTALIKE) had much better acceptance amongst evaluators, although students rated and performed less well in TrueTooth replicas due to their greater level of difficulty.