periodontal file

例句：

1. 1. Periodontal disease is a common problem in people over the age of 30.
   牙周病是30岁以上人群中常见的问题。
2. 2. The dentist performed a thorough examination of the patient's teeth and found signs of periodontal disease.
   牙医对患者的牙齿进行了彻底的检查，发现了牙周病的迹象。
3. 3. Regular dental check-ups are essential for preventing periodontal disease.
   定期的牙科检查对于预防牙周病至关重要。