One and a half year old baby mouth ulcers, may be the baby’s teeth, decreased immunity, genetic factors such as caused by the need for anti-inflammatory pain, to prevent re-infection. 1. baby’s own factors: baby’s new teeth are relatively sharp, the oral mucosa is more tender, the teeth may stimulate the oral mucosa, thus causing ulcers, you can use zinc glycyrrhizate and other medications, and at the same time need to pay attention to the baby carefully clean the teeth, so as not to cause ulcers again. 2. recurrent oral ulcers: immune abnormalities, family genetic factors may cause oral ulcers, and has a periodic, recurrent, self-limiting characteristics. You can use drugs such as triamcinolone, furacillin, cidadex iodine tablets for anti-inflammatory, lidocaine gel and other drugs for pain relief, physical therapy and so on. The occurrence of mouth ulcers need to pay attention to oral hygiene, it is recommended to take the baby as soon as possible to seek medical treatment, under the guidance of the doctor to use drugs.