The "Painting by Numbers Method" for education of students in crown preparation

3D-printed coloured tooth model for inlay preparation in pre-clinical dental education

INTRODUCTION

Accurate inlay preparation is extremely important in pre-clinical training. However, there is a lack of tools to guide students to efficiently practise inlay preparation. Therefore, a 3D-printed coloured tooth model for inlay preparation was designed to guide beginners to practise inlay preparation by themselves according to different colour prompts. This study aimed to evaluate the benefits of using a 3D-printed coloured tooth model in the pre-clinical training on inlay preparation.

MATERIALS AND METHODS

Twenty-eight students in their fourth-year undergraduate dental program participated in this study. The participants were randomly assigned to two groups for the inlay preparation. Group 1 prepared a plain tooth model for the first and fourth attempts and a 3D-printed coloured tooth model for the second and third attempts (n = 14). Group 2 prepared four plain tooth models (n = 14). The first and fourth tooth models prepared by both groups were scored using an evaluation system (Fair Grade 2000, NISSIN). Next, questionnaires answered by students were used to evaluate the benefits of using a 3D-printed coloured tooth model and self-evaluate hands-on ability using a grading system (1 = strongly agree, 2 = agree, 3 = neutral, 4 = disagree, and 5 = strongly disagree). The scores were evaluated statistically using the Mann-Whitney U test, and the given grades are displayed as percentages and mean values.

RESULTS

There was an overall increase in the clinical confidence of all students after repeated attempts to prepare an inlay; however, students from group 1, who had used the 3D-printed coloured tooth model, had more positive experiences and comments. The 3D-printed coloured tooth model for inlay preparation has been widely praised by participants. Comparing the average score of the first and fourth preparations, the average score of group 1 increased by 12% (Ø 54.46 ± 8.33, Ø 61.11 ± 7.13, p = .090), while that of group 2 increased by 0.72% (Ø 56.39 ± 9.59, Ø 56.80 ± 8.46, p = .925).

CONCLUSION

Students favoured the use of the 3D-printed coloured tooth model, and this improved the average score for inlay preparation. The 3D-printed coloured tooth model for inlay preparation is expected to play an important role in dental education in the future.

Preclinical motor chunking and fine motor skill learning in fixed prosthodontics: Contribution of 3D printing and satisfaction of dental students

INTRODUCTION

In fixed prosthodontics, simulators are essential to students for a progressive transition from preclinical to clinical condition. With the 3D printing technology, we developed resin bars allowing students to better visualise by motor chunking technique. Main objectives of this work were to describe this teaching methodology used in preclinic among different promotions of second, third and fourth dental years and to evaluate students' feedback.

MATERIALS AND METHODS

Two hundred seventy resin strips were digitally designed and printed in resin. All participants from second, third and fourth had to fulfil a User Experience Questionnaire (UEQ) after the preclinical work. The scales of this questionnaire covered the complete impression of the user experience. Both classical aspects of usability (efficiency, insight and reliability) and aspects of user experience (originality, stimulation) were measured.

RESULTS

For the second dental years, 'Attractiveness', 'Stimulation' and 'Novelty' were considered 'Excellent'. For the third dental year, novelty average was considered as 'Excellent'. For the fourth dental year, 'novelty' was considered as 'Good'.

DISCUSSION

The resin plates used in this study are original and stimulating for the students, especially for the second-year dental students who found the exercises useful for their learning. This method can also be used by creating scenarios close to the clinical situations encountered in dentistry departments (more dilapidated teeth, preparation of inlays, post and core, etc.). This 3D printed simulation model is not intended to replace the Frasaco® models but is a complement to the learning process.

Evaluation of a new 3D-printed tooth model allowing preoperative ICDAS assessment and caries removal

INTRODUCTION

Teaching caries lesion management with operative care requires tooth models with highly realistic anatomical detail and caries lesions that can be assessed using ICDAS. This study aimed to develop and evaluate a new 3D-printed teeth model for ICDAS assessment and caries removal for pre-clinical hands-on education.

METHODS

Printable tooth with different layers for enamel, dentin and carious lesions was designed and tested by 31 dental students. They were asked to visually and radiologically assess the ICDAS severity of the simulated carious lesions, establish the therapeutic strategy according to CariesCare 4D, and perform a qualitative assessment of the models based on five-point Likert scale items.

RESULTS

Concerning carious lesions, the texture was realistic, and the shade was adequate for 94% and 97% of the participants. Ninety per cent of the participants found the model adequate to perform an ICDAS visual assessment. Seventy-four per cent of the students found the hardness adequate. Concerning the difference in shade and the noticeable hardness difference between enamel and dentin, participants have mixed agreement with a proportion of 61% and 55%, respectively. All the participants agreed these 3D-printed models provide a good caries simulation, are suitable for hands-on operative dentistry courses, and that learning outcomes better than the standard model.

CONCLUSION

The present work shows that rapid prototyping paves the way for customized educational models capable of supporting operative but also preoperative skills. 3D printing opens up new opportunities by reducing the gap between pre-clinical training and clinical reality in caries management, which can positively impact the quality of patient care.

Modular training model for education of students in restorative and prosthodontic dentistry

INTRODUCTION

At the moment, no commercial model solution is available for the individualisation of the dentition depending on the clinical case scenario. Furthermore, the realistic training of most restorative and prosthodontic procedures on a single dental study model is not possible. The aim of this study was the creation of a new training model to fill this gap.

MATERIALS AND METHODS

Complete upper and lower jaw models were created based on existing scans and radiological data from a patient. All components for 100 complete models and 1128 teeth for the training were produced with a SLA-printer. Overall, 94 voluntary students attending the first and second preclinical course in prosthodontics tested the functionality of the model with three different tooth types against a standard dental study model and real teeth. After the training, the model was rated in a questionnaire.

RESULTS

The production of the models and teeth was feasible. The overall rating of the different teeth was worse for type I (Ø 3.6 ± 1.1), significantly better for type II (Ø 2.5 ± 1.0) and type III (Ø 2.4 ± 1.0) than a standard typodont tooth (Ø 2.7 ± 1.1). The new model was rated significantly better overall (Ø 2.6 ± 1.0) than the standard training model (Ø 3.0 ± 1.1).

CONCLUSIONS

The aim of this study was fulfilled. A superior training model was created with equivalent and better tooth types. The new teeth were outstanding in terms of cost-efficiency, appearance and feeling during preparation.

Effect of a digital assessment system for the preclinical tooth preparation of metal-ceramic crowns: A pilot study

STATEMENT OF PROBLEM

Tooth preparation is a fundamental aspect of prosthodontics and serves as a focal point in preclinical courses. Conventional pedagogy relies heavily on the expertise of instructors, whereas digital technology has the potential to offer instantaneous feedback. The efficacy of a digital assessment system in comparison with traditional teaching methods remains uncertain.

PURPOSE

The purpose of this study was to compare the training effects of traditional assessment and digital evaluation on tooth preparations for the metal-ceramic crowns performed by preclinical students on the convergence angle and tooth reduction.

MATERIAL AND METHODS

A total of 40 predoctoral students were randomly divided into the digital group and the traditional group to complete tooth preparation for a metal-ceramic crown on a left mandibular first molar. Students in the traditional group were taught by an experienced instructor, while the digital group students were trained by an objective digital assessment system without instructor guidance. Each student completed the tooth preparation in 20 min, received feedback according to the respective training methods, and later prepared another tooth. In this way, all students completed 4 tooth preparations in 2 weeks. All preparations were evaluated by an optical scanner. Parameters for comparing the digital group with the traditional group were the convergence angle and reduction at different stages. Questionnaires on the digital training system were answered by the students of the digital group. The t tests or Wilcoxon signed rank tests and chi-squared tests were used to analyze the differences between the 2 groups (α=.01).

RESULTS

A decreasing trend in convergence angle was seen in both groups, but the 2 groups were statistically similar (P>.01). After training, a decreasing trend was seen in under-reduction and overreduction on 5 surfaces in the digital group. Conversely, in the traditional group, a noteworthy increase was seen in under-reduction on the distal surface (P=.002). Nevertheless, no significant difference was found between the 2 groups (P>.01). According to the results of the questionnaire, over 80% of the students had a positive attitude toward the digital assessment system, and more than 80% of the students expressed their interest in the digital assessment system for tooth preparation training.

CONCLUSIONS

Traditional teaching and digital feedback provided similar training effects to improve the quality of tooth preparations for preclinical dental students.

Comparison of digital and conventional assessment methods for a single tooth preparation and educational satisfaction

INTRODUCTION

Digital feedback for tooth preparation can provide dental practitioners with more objective and accurate evaluations compared to conventional methods. This study aimed to evaluate the educational effect and satisfaction of digital feedback compared with those of the conventional putty index method for tooth preparation.

MATERIAL AND METHODS

Forty-eight third-grade dental students were selected. All students performed a full-coverage preparation on a right mandibular first molar resin tooth. They were randomly divided into four groups (n = 12)-no guide (control), putty index, digital feedback, and digital and putty index assessment. Three-dimensional analysis was performed using an analysis software (GomInspect 2018, Gom) to evaluate the amount of tooth structure removed. At the end of the practice, the students completed a questionnaire to evaluate the educational satisfaction of the respective methods.

RESULTS

There was no statistical significance of the amount of preparation amongst groups in most of the measured areas only except for several specific points. Overall occlusal surface showed 0.99 ± 0.27 mm in the N group (no guide) and 1.15 ± 0.31 mm in the D group (digital feedback), and overall axial surface showed no statistical differences (p > .05). The groups that used digital assessment showed a high level of satisfaction compared with conventional assessment.

CONCLUSIONS

It was difficult to confirm that the digital-based feedback promotes accurate tooth preparation compared to conventional feedback within the limitation of this study. However, it improved educational satisfaction and permitted objective evaluation.

Three-Dimensional printed model for preclinical training in oral radiology

INTRODUCTION

3D printing is experiencing significant growth in the teaching and learning process. This study aims to present a 3D printed skull model for preclinical intraoral radiographic practice.

MATERIALS AND METHODS

Two 3D printed mannequins were created. One mannequin used an STL file of a skull that was edited using two 3D modelling software (Meshmixer and Netfabb). The second mannequin was designed directly from a patient's segmented CBCT data and then converted into an STL file. Both mannequins were printed using fused deposition modelling (FDM) technology and polylactic acid (PLA) filament; teeth for the second mannequin were also printed using digital light processing (DLP). The printed skull bones were attached, the mandible was articulated to the articular fossa of the temporal bone, and the teeth were inserted into the alveoli. Intraoral radiographs of both mannequins were taken using a digital sensor (RVG 5100, Carestream).

RESULTS

Both 3D printed mannequins showed satisfactory radiographic appearance, allowing geometric representation of each intraoral radiographic projection, regardless of STL file origin. Anatomical structures, such as the periodontal ligament space, zygomatic process of the maxilla and intermaxillary suture, were represented. The material cost of the first and second printed prototype was $34.00 and $39.00, respectively.

CONCLUSIONS

The use of 3D printed models is presented as an alternative to artificial commercial phantoms for the preclinical training of intraoral radiographic techniques through the combined benefits of superior radiographic projection quality, the possibility of model manipulation and an affordable price.

Dental students' self-reported confidence level in restorative crown and bridge procedures: A UK quantitative study

INTRODUCTION

Graduating confident students who can flourish and develop in their future career is an important outcome of dental education. The aim of the study was to gain an insight into students' self-reported level of confidence in restorative crown and bridge procedures, highlighting in which stage of the process students have the highest and lowest confidence, depending on the level of supervision required.

MATERIALS AND METHODS

Fourth and final year students (n = 85) were invited to complete a 71-item closed questionnaire specific to self-reported confidence based on the level of supervision required in stages of crown and bridge procedures. Clinical activity for each student from their portfolio system was collected. Non-parametric tests, specifically the Mann-Whitney U-test was used to analyse the continuous non-normal data.

RESULTS

A response rate of 65% was obtained. Final year students were more confident in crown and bridge procedures than fourth year students. Fourth year students were more confident in bridges, whilst final year students were more confident with crowns. Majority of students expressed "average confidence requiring minimal supervision" in crown and bridge procedures. An association between clinical activity, confidence and year of study was noted. Gender was not strongly associated with confidence. Stages in crown and bridge procedures were noted where students lacked confidence.

CONCLUSION

The study highlighted areas in which students were most and least confident in crown and bridge procedures. A positive relationship between clinical activity in crown and bridge procedures and student self-confidence has been noted for both years, though slightly higher in the bridge procedure for fourth year students. We attribute this to the fact that fourth year students had recently completed their bridge competency assessment. Upon graduating, final year students still require supervision and reported average confidence in certain aspects of crown and bridge procedures, namely occlusal, bevel and axial reduction.

3D Digital technology as an alternative educational tool in preclinical dentistry

INTRODUCTION

The advancement of 3D digital scanners has allowed educators to uphold the quality of education whilst implementing novel methods of assessment.

OBJECTIVE

The purpose of this study was to compare two evaluation methods, conventional and digital scanned assessments, on student cavity preparations and students and faculty's perceptions of these assessment methods.

METHODS

Predoctoral students performed Class II amalgam and Class III resin composite preparations on simulated teeth for their preclinical competency examinations. Two calibrated faculty evaluated the students' preparations using dental instruments for conventional assessments and 3D scanned images for digital assessments. Faculty scores from both assessment methods were compared and statistically analysed (p < .05). Students also self-assessed their performance using the digital scanned images and filled out a perception survey.

RESULTS

There was no statistically significant difference between the conventional (Class II; 73.3 ± 12.2 and Class III; 82.5 ± 8.9) and the digital assessment with scanned images (Class II; 71.3 ± 11.0 and Class III; 82.2 ± 8.2). Faculty scores from both methods have shown a trend of comparability. Most students agreed that digital ideal preparation models were useful (84.2%) and almost all students agreed that digital technology helped them learn operative dentistry (91.1%). In contrast, most students agreed that conventional assessment should be the main self-evaluation system (82.2%) and disagreed that digital assessment is more effective than conventional self-assessment (68.3%).

CONCLUSION

Our study demonstrated that 3D digital technology could be an alternative and/or supplementary educational tool to aid in upholding the quality of dental education.

3D printed versus commercial models in undergraduate conservative dentistry training

INTRODUCTION

The treatment of carious lesions is one of the most fundamental competencies in daily dental practice. However, many commercially available training models lack in reality regarding the simulation of pathologies such as carious lesions. 3D printed models could provide a more realistic simulation. This study provides an exemplary description of the fabrication of 3D printed dental models with carious lesions and assesses their educational value compared to commercially available models in conservative dentistry.

MATERIALS AND METHODS

A single-stage, controlled cohort study was conducted within the context of a curricular course. A stereolithographic model was obtained from an intraoral scan and then printed using fused deposition modelling. These models were first piloted by experts and then implemented and compared against commercial models in a conservative dentistry course. Experts and students evaluated both models using a validated questionnaire. Additionally, a cost analysis for both models was carried out.

RESULTS

Thirteen dentists and twenty-seven 5th year dental students participated in the study. The 3D printed models were rated significantly more realistic in many test areas. In particular, the different tactility and the distinction in colour was rated positively in the 3D printed models. At 28.29€ (compared to 112.36€), the 3D printed models were exceptionally cost-efficient.

CONCLUSIONS

3D printed dental models present a more realistic and cost-efficient alternative to commercial models in the undergraduate training of conservative dentistry.