Strength improvement of critical-sized three dimensional printing parts by infiltration of solvent-free visible light-cured resin.

The use of light-cured acrylate resin as an infiltrant can enhance flexural modulus and flexural strength of natural polymers based three dimensional printing (3DP) parts to be closed to general use of polymethyl methacrylate resin. It was observed that flexural properties of infiltrated specimens were influenced by infiltration conditions. Curing by normal halogen light bulb was more practical for critical-sized 3DP parts than curing by typically small probe of dental visible light curing unit (VLC). Similar levels of flexural properties were obtained from these two methods. Post-heated treatment after curing was also observed to further increase the flexural modulus and strength of infiltrated samples. However, flexural strain at break was not affected by different curing conditions. Preliminary In Vitro toxicity test of infiltrated 3DP parts showed that the cells which were in contact with samples were healthy. No inhibition zone was observed.