# Teaching punch biopsy and suturing with a 3D-printed skin model: design and integration into the medical curriculum

## TL;DR

A 3D-printed skin model was developed and used in medical training to teach punch biopsies and suturing, offering a realistic and cost-effective alternative to traditional methods.

## Contribution

A low-cost, reusable 3D-printed skin model was created and integrated into medical education for practical skill training.

## Key findings

- The 3D skin model successfully simulated tactile and functional aspects of punch biopsies and suturing.
- Student feedback showed increased confidence in performing these procedures on humans after using the model.
- The model had a low production cost of 0.62 € per unit, making it a cost-efficient training tool.

## Abstract

In the 2019/2020 winter semester, the University of Augsburg’s Faculty of Medicine introduced a competence-oriented model degree program with a spiral curriculum integrating theory and practice. A key feature, the clinical longitudinal course, emphasizes practical skills such as skin examination. Existing training materials for punch biopsies, e.g., foam models and fruit, have proven insufficient. This project aimed to create a realistic, cost-effective, reusable three-dimensional (3D) skin model to improve the teaching of punch biopsy and suturing techniques.

The 3D skin model was developed in a multistage process. It began with a 3D scan created via a handheld 3D scanner and refined in 3D modeling software. A fused deposition modeling (FDM) printer produced negative molds that were filled with silicone, resulting in a realistic model. After several iterations, a design was achieved that successfully simulated the tactile and functional aspects of punch biopsy and skin suturing. Student feedback was collected through an anonymous online questionnaire assessing perceived realism, usefulness for practicing punch biopsies and suturing, and impact on their confidence.

The silicone-based skin simulator debuted in the 2023–2024 winter semester’s ‘examination of the skin’ course. A total of 82 students participated in the course, of whom 58 completed the evaluation questionnaire. The students used the model to perform punch biopsies and suturing, reporting that its material properties allowed these procedures to be practiced under course conditions. With a low production cost (of 0.62 € per model) compared to commercial models, it is a cost-efficient alternative to previous materials. The students provided positive feedback, reporting increased confidence in performing these procedures on humans for the first time.

The 3D training model is an important advancement in introducing 3D technologies in practical training, providing realistic, cost-effective practice for punch biopsy and suturing. Its successful integration into the curriculum highlights its potential for broader applications in medical education. The evaluation indicated that the model provided realistic skin properties and proved effective for practicing punch biopsies and suturing, thus addressing the limitations of traditional training materials.