What is the ruling on filing teeth due to yellowness and chipping at their base?

It is understood from the Hadith that the blameworthy alteration of Allah's creation is that which is sought for the sake of beautification. Accordingly, it is permissible to file teeth for treatment or to remove severe disfigurement. The yellowing of teeth along with their breakage is considered a harm that permits filing if no other means are available to remove it.