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

Abstract

Introduction No commercially available solution to improve the teaching of a crown preparation directly on typodont teeth exists at the moment. To fill this gap and support the supervisors of dental courses, a printable and inexpensive tooth was created for structured self‐assessment. The aim of this study was to test this printable tooth under realistic pre‐clinical situations. Materials and methods A two‐coloured, double‐layer practice tooth was developed. This tooth was consisting of a layer for a correct preparation and the crown. All printed teeth were produced with a stereolithographic printer. 35 voluntary second‐year dental students in the second pre‐clinical course in prosthodontics were randomly divided into two groups. All students had experience with typodont teeth and models. The first group was trained on four standard model teeth. The second group used model teeth for the first and fourth attempt and printed teeth for second and third attempt. The preparations of the students were scanned by an in‐lab scanner and the surface deviations in contrast to a perfect preparation were measured. The differences between the first and fourth attempt were calculated. Benefits of the printed tooth were also evaluated by a questionnaire using German school grades completed by the students (1 = Excellent, 2 = Good, 3 = Satisfactory, 4 = Adequate, 5 = Poor, 6 = Unsatisfactory). Results The workflow was feasible and cost‐effective regarding the production of the printed teeth. The overall rating of the printed tooth in the questionnaire was good (Ø 2.1 ± 0.22). Students reported different advantages of this method in the free text. The comparison of the preparation between the first and fourth attempt showed that there was a significant better preparation with the printed teeth. The complete preparation had median values of 0.05 mm (Group1: standard model tooth) and −0.03 mm (Group2: printed tooth) (P = .005). Divided into single surfaces, the vestibular and occlusal regions were significantly better. The vestibular surface was 0.11 mm (Group1) and −0.04 mm (Group2) (P = .018). The occlusal surface was 0.13 mm (Group1) and −0.05 mm (Group2) (P = .009). Conclusions The aim of this study was fulfilled. The printed tooth was tested successfully in a pre‐clinical course. The feasibility of this teaching concept was confirmed by the questionnaire and the analysis of the preparation form. A significant difference to a standard model tooth was measurable. The students had the possibility to learn a correct crown preparation on a standardised two‐layered tooth with included preparation. This printed tooth enabled the students to control the crown preparation directly on their own.

3D printed versus commercial models in undergraduate conservative dentistry training

“…There are some studies that sought to investigate the educational benefit of 3D printed models in dentistry and maxillofacial surgery 8–16 …”

“…There are some studies that sought to investigate the educational benefit of 3D printed models in dentistry and maxillofacial surgery. [8][9][10][11][12][13][14][15][16] To train the excavation of a carious lesion and the preparation of a cavity Kroeger et al used the PolyJet technique to 3D print individualised tooth models which received positive feedback from students. However, students criticised the missing differentiation in colour between the carious lesion and the healthy tooth structure.…”

“…Studies from Höhne et al, [12][13][14][15] Marty et al 16 and Soares et al 9 used the dual-light processing technique to print individualised tooth models and added pathologies such as carious lesions digitally in a computer aided design method. Compared to commercial KaVo (KaVo, Biberach an der Riß, Germany) models, these models were rated positively by students and experts.…”

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

“…Likewise, we must consider the large amount of time students spend learning and checking their preparations. Therefore, adequate equipment should be available to avoid long waiting times amongst students and, without a doubt, will require considerable high financial investment on the part of dental schools 5,22,30‐32 …”

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

“…The best way to ensure this could be through practice on phantom heads in the skills laboratory and regular patient flow for exposure to crown and bridge procedures. Other methods have been reported to improve the teaching of crown and bridge preparations including the use of 3D multilayered printed teeth with included preparations, 10,11 the use of CEREC prepCheck (Dentsply Sirona, York, Pennsylvania, USA) for the control of a preparations 12,13 and a more advanced method utilising virtual 3D models 14,15 . However, two factors appear to threaten the UK undergraduate clinical experience.…”