Evaluation of Dimensional Changes of 3D Printed Models After Sterilization: A Pilot Study

To assess the effect of two of the most commonly used sterilization techniques on 3D printed clinical objects.

The two sterilization methods used in our hospital and investigated in this paper are: Steam heat and Gas plasma. Three objects were printed and tested in this study: a tooth replica, an orthognathic final splint, a surgical cutting guide for the purpose of mandible reconstruction. For each of the 3 objects, 4 copies were made: one original STL object, one copy of the object pre-sterilization, one copy of post-steam heat sterilization, and one copy of post-gas plasma sterilization. Each printed object was scanned using a high resolution CBCT protocol and the compared (morphologically and volumetrically).

At the level of volumetric changes, no difference was found between pre and post-sterilization for both methods evaluated. As for the morphological changes, only differences were noticed with the orthognathic splint object indicating deformation of the printed splints after sterilization. Larger differences were observed with heat sterilization, making it less reliable.

Sterilization of dental objects to be used in a clinical setting may lead to deformation of the printed model, especially for heat sterilization. Further investigations are needed to confirm these findings.