Flexural impact force absorption of mouthguard materials using film sensor system

Purpose Several methods have been used to measure the impact force absorption capacities of mouthguard materials; however, the relationships among these measurement systems have not been clearly determined. The purpose of the present study was to evaluate the impact force‐absorbing capability of materials using a drop‐ball system with film sensors and load cells to clarify the relationship between these two sensor systems. Materials and methods Disk‐shaped specimens (1, 2, and 3 mm thick) were prepared using three commercial thermoplastic mouthguard materials (Bioplast, Impact Guard, MG 21) and one experimental mouthguard material [mixture of Poly (ethyl methacrylate)]. Impact force was applied by letting a stainless steel ball drop free‐fall onto the specimens and then measuring the impact load under each specimen using a film sensor system and a load cell sensor system. Results The total load measured with the film sensor system decreased with an increase in mouthguard thickness, while almost none of the transmitted impact forces measured with the load cell system were statistically different. Conclusions The film sensor system was considered to be superior to the load cell system because the maximum stress and stress area could be determined.