Reusability of dental models modeled with virgin PLA added to recycled polylactic acid (PLA)

Abstract

 This study aimed to reduce industrial waste in dentistry. After models made of polylactic acid (PLA) were sculpted and polished by a fused filament method (FFF) 3D printer, we investigated whether adding different proportions of virgin PLA to reused PLA filaments would increase the number of times they could be reused. Three cycles of recycling were performed with virgin PLA added at 25%, 50%, and 75% of the recycled PLA to verify the accuracy. The same provisional crown was placed on a PLA model and photographed using micro-computed tomography, and the marginal fit was measured using 3D image analysis software to determine accuracy. It was suggested that the 25% virgin PLA group could be reused three times, the 50% virgin PLA group twice, and the 75% virgin PLA group once.