Abstract
One in ten Japanese people suffer from ingrown toenail, a safe and easy correction treatment for ingrown toenail is required. The corrective device which enable fix the ingrown toenail to normal shape was developed. This method is soften the nail by immersing the nail in a hot bath then, correct normal shape, the corrected shape is retained by subsequent fully drying. The properties of a human nail after hot bath are not reported. To clarify the condition for using the device such as bathing and drying, the change in hardness of the human nail with various bating time, temperature and drying time were measured. In addition, tensile tests were carried out in the conditions of saturated softening and after drying. It was revealed that the hardness and the elastic modulus are reduced about one third by immersing the nail in the hot bath at 37-40 ℃ for ten minutes.
