Frequent mouth ulcers may be related to the following reasons: 1, the lack of vitamins and trace elements caused by. The lack of vitamins and trace elements is mainly related to picky eating or partial eating, in the daily diet if you are not willing to eat fruits or vegetables, it is very easy to cause vitamins; 2, there are dentures in the mouth, and the quality of dentures is not qualified, dentures will often stimulate the oral mucosa, causing mouth ulcers; 3, the teeth are not aligned, if the teeth are tilted outward, it is easy to bite to the oral mucosa when eating. The location that is often bitten will easily cause mouth ulcers; 4, the body resistance is too low, often stay up late, irregular work and rest or older people are prone to this symptom. For patients with frequent mouth ulcers, it is best to go to the hospital for oral examination, if the cause of oral disease, need to be treated as soon as possible.