Abstract:

Background:
The capacity to recognize the 3-dimensional (3D) features of teeth is an essential skill for the practice of dentistry. At University College Cork tooth morphology is taught in the second year of the dentistry programme. This topic requires visualization and understanding of the various features of the human teeth and their dynamic interactions with each other. Traditional teaching methods include studying with extracted and/or plastic teeth, drawings and wax/chalk carvings, and have been supplemented with 3D computer generated models, all of which allow for the acquisition of the necessary skills and knowledge. The assessment of modules via quizzes (with feedback) promotes active learning, assists in examination preparation and has been shown to motivate students and can be invaluable.

Aim:
The aim of this study was to develop and assess a tooth morphology quiz which would incorporate interactive digital 3D models of teeth.

Methodologies:
Extracted human teeth and high quality plastic teeth were obtained and meticulously cleaned. The tooth surfaces (crown, root/s) were individually scanned using a dental 3D surface scanner (Incise, Renishaw, Gloucestershire, UK) and exported as .stl files. Hard impressions (Photo curing resin, Voco, Cuxhaven Germany) of the occlusal surfaces were also scanned to capture the intricate occlusal details and exported. All scans (2-6 scans/tooth) were sequentially imported to GOM inspect software (V7.5 SR2, Braunschweig, Germany), aligned and stitched into complete 3D digital models (.stl files) using a novel protocol.

Once scanned, all 32 teeth were imported to Blender (V2.7.3) and applied with a custom material. The 3D quiz environment was created in the Unreal Engine (v4.9.2). The environment consists of a FDI dental notation charting system, 3D tooth models, data gathering systems, feedback screens and model view manipulation interactions. To undertake the quiz, ten teeth are selected at random and the student can interact with the model (zoom and rotation features) in 3D view before submitting to the correct grid notation. On completing the quiz, the student is presented with a feedback screen containing visual and textual feedback for the wrong answers. The system's backend records the student's score, time taken, date, and creates a list of incorrect answers for further analysis.
The system was subjected to an informal pilot usability study with six third year medical students.

Results:
Usability pilot data collected indicates that students enjoyed undertaking the quiz and found it very easy to use. The students also indicated that the quiz demonstrates the 3D features of the teeth clearly. However, participants noted that the quantity of textual information on the feedback screen was overwhelming. Also, it was reported that it was unclear where to submit the tooth to the grid.

Conclusion:
The pilot study feedback shows promise for such a 3D quiz in dental education. Solutions to the issues identified in this study have now been implemented in preparation for formal testing with dental students. It is anticipated that the proposed 3D tooth morphology quiz will aid students with learning and retaining dental morphology knowledge.

*The first three authors contributed equally to the work.

Keywords:

Dental students, tooth morphology, human teeth, 3D tooth morphology teaching, online quiz.