periodontal disease

例句：

1. 1. Hehas been suffering from periodontal diseasefor years.
   他多年来一直患有牙周病。
2. 2. The dentist advised him to take careof his teeth and prevent periodontaldisease.
   牙医建议他要好好照顾牙齿，预防牙周病。
3. 3. Thepatient was referred to aspecialist for treatment of periodontal disease.
   患者被转介给一位专家治疗牙周病。