Our dental insurance plan covers fillings on posteriors but not cosmetic whitening procedures.

我們的牙科保險方案給付後牙的補牙，但不包含美白療程。

The clinic emailed patients a reminder to schedule cleanings for their posteriors every six months.

診所寄電子郵件提醒病患，每六個月要預約一次後牙洗牙。

During the business trip, Mark cracked one of his posteriors and needed an emergency dentist.

出差期間，馬克的一顆臼齒裂了，必須緊急看牙醫。