Occult tooth fractures are closely related to both structural defects and improper use. To prevent tooth fracture and fracture, we should advocate the correct use of teeth and minimize the influence of their own bad structure. 1, do not use teeth to gnaw or bite too hard objects such as metal bottle caps; 2, chewing bones and other hard food, the force should be small, slow; 3, the middle-aged and elderly people should be regular oral examination, if there are hidden cracks can be preventive filling, found too sharp, steep cusps can be moderately adjusted grinding change; 4, heavy deep overlap, teeth heavy wear, especially the performance of night grinding patients, should be fitted and wear occlusal pads to sleep .