Regular use of Xylitol has been shown to help reduce dental plaque - the first stage of cavity development, tartar formation and toothstaining - and promote better oral health.
有显示说常吃木糖醇有助于减少齿菌斑——蛀洞，牙石，牙渍形成的第一步——还有提高口腔的健康。
2
No amount of cleaning will remove the severe staining left by tetracycline or systemic disease because these pigments lie inside the tooth; you'll have to take more aggressive measures against these.