167 - Development of a 3d Printed Task Trainer for Alveolar Bone Graft Procedure

Poster Board Number: 167
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Odd poster #s – first hour
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Co-authors:

Brooke French - Department of Plastic Surgery - University of Colorado; Nicholas Jacobson - Inworks Innovation Initiative - University of Colorado

Abstract Body : Alveolar Bone Graft (ABG) is a complex surgery due to a series of high-consequence maneuvers involving a child’s periosteum and mucosal tissues, which are susceptible to tearing and crushing. Current surgical training models replicating alveolar clefts use mixed methods such as 3D printing, silicon injection molding, and adhesives to produce models, resulting in limited resolution and tissue properties. A fully 3D printed technique allows for increased resolution and tissue variation to create ABG training models with tissue layers that replicate the feel of bone, periosteum, and mucosa. However, replication of oral cavity tissues for surgical training is not well established because mechanical properties of oral mucosa described in the literature are not relevant for how surgeons are trained. Expert surgeons develop a feel of the tissues involved in ABG, leading to proper tissue handling during the procedure. We have created a training model that replicates an alveolar cleft and the feel of mucosal flaps intended to enhance teaching of the procedure. Opensource CT and MRI scan data are used to segment bony and soft tissues. Surface-based mesh and voxel modeling are used to model the alveolar cleft and oral mucosa. Voxel printing is used to mix different ratios of printing materials to replicate the feel of periosteum and mucosal layers. The model’s layers are tested for appropriate feel and suture retention limits with guidance from an expert surgeon. The printed material’s elastic modulus is calculated using stress-strain testing according to ASTM Standard 638 and printed on a multi-material polyjet printer. Using voxel printing methods, a task trainer with bone, periosteum, and mucosal layers is made. The layers are printed using out of the box materials for bone and custom mixtures for periosteum and mucosal layers. With guidance from an expert surgeon, the model’s layers are assessed for appropriate feel during cutting, elevation and suturing. Elastic modulus of the printed material is compared to literature values. Using voxel printing bone, periosteum, and mucosa can be developed with expert surgeon guidance and assessment to verify the feel of the materials are relevant to the ABG procedure. These materials can be combined to create an anatomically accurate model of an alveolar cleft that can be used to train surgical residents. Future studies can test the model’s effectiveness as a training tool measured by motion fluidity, motion economy, and tissue handling. Voxel printing allows for the development of a task trainer with materials mimicking the feel of real tissue. This fidelity increases the trainability of complex procedures with delicate tissue layers, and combined with task trainers, leads to better trained surgeons and improved surgical outcomes for patients.