If the bump to which you refer is the bony prominence immediately above the "star" , this is a formation known as a "torus mandibularis
". This is a normal anatomic variant, and is the result of a growth of normal bone that extends beyond the usual contours. About 20% of people have either mandibular tori or palatal tori (on the roof of the mouth).
Torus mandibularis, because it is a normal variant, does not usually require any treatment. However, as you have already discovered, they can interfere with the comfort of a partial denture
. This issue usually only happens when the tori get quite large, as they sometimes do-- see:
Your tori do not appear to be sufficiently large to warrant surgical removal. However, your partial denture may require modification or replacement to permit comfort. It is customary to design a lower partial denture with "relief"-- a small gap between the bar or denture base in the front and the tissues immediately behind the lower front teeth, to eliminate pressure between the denture and the thin tissues in this location. Your denture may be old, and may have settled into your torus, and the pressure between the denture and this bony lump can cause a pressure ulcer to occur. Your dentist may be able to grind off a sufficient amount of material at the place of tissue pressure to allow you to wear your denture comfortably. If not, your dentist may need to construct a new denture with additional relief in the problematic area to prevent tissue compression and allow comfort.
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