The effect of aging on the mechanical properties of 3-dimensional printed biocompatible resin materials used in dental applications: An in vitro study

Abstract

The mechanical properties of biocompatible printable resin materials in an intraoral environment is still being investigated. This study aimed to assess the effect of the aging process on the mechanical properties of resin samples produced by stereolithography appearance (SLA) and digital light processing (DLP) 3-dimensional printer systems. The cylindrical sample (4.00 × 20.00 mm) was designed by software, and the data were transformed into digital format. A DLP printer (n= 40) and an SLA printer (n= 40) carried out the printing process. The aging procedure was applied to 20 samples from each group using a thermocycling device. After the aging procedure, the samples were placed in the universal testing device for the 3-point bending test. This study showed that the aging procedure decreased maximum load, bending stress, and Young's modulus values and increased maximum deflection values of the DLP group (P<0.01). However, no statistical difference was detected in the parameters compared with the SLA group except for the maximum deflection values. Furthermore, statistically significant differences were found between maximum deflection and Young's module values of SLA and DLP control and study groups (P<0.05). This invitro study revealed that the biocompatible printable resin materials produced by DLP and SLA printers had the mechanical strength to resist the values resembling the physiological occlusal forces even after the aging procedure and could produce intraoral appliances.