periodontics

例句：

1. 1. Periodontitis is a commoncondition that affects the gums andteeth.
   牙周病是一种常见的状况，影响牙龈和牙齿。
2. 2. The dentist performed athorough examination of my teeth and recommended periodontitis treatment.
   牙医对我牙齿进行了彻底的检查，并推荐了牙周病治疗。
3. 3. Periodontitiscan lead to serious health problems if leftuntreated.
   如果不治疗，牙周病可能会导致严重的健康问题。