noun 下载 🔗分享 牙骨质，牙骨 Cement。 A bony substance that covers the root of a tooth; cement. Examples : "The dentist explained that the cementum, a hard tissue covering the root of the tooth, helps anchor it to the jawbone. " 牙医解释说，牙骨质，也就是覆盖在牙根上的一层坚硬组织，有助于将牙齿固定在颌骨上。 anatomy body part medicine 与AI对话词汇游戏阅读练习
