The torus, which appears only in adulthood, is a developmental anomaly. It can continue to slowly grow throughout life. About 27/1,000 adults experience this condition. It may be the outcome of mild, constant decrease in blood supply to the membrane covering the surface of the bone resulting from mild pressures on the thin nasel membrane or a turning force of the arch of the lower jaw or sideways pressures from the roots of the underlying teeth, though this theory is as yet unconfirmed.

Torus consists of dense, layered bone with scattered osteocytes and small marrow spaces filled with fatty marrow and other tissues. A slim frame of outer bone on top of inactive cancellous, or porous, bone with considerable fatty or hematopoietic (red blood cell-forming) marrow surrounds some lesions.

The torus does not require treatment unless it becomes large to the point where it interferes with denture placement or mouth functions, or suffers from repeated traumatic surface ulceration. Ulceration can be caused by sharp foods, such as potato chips or fish bones. Treatment usually consists of chiseling off the lesions.

The presence of numerous tori may indicate Gardner's syndrome, a condition characterized by bony tumours of the skull, polyps in the colon, extra teeth, and fatty cysts in the skin.

Dental Challenges in the presence of tori:

1 - Tissue over the tori is usually quite thin and easily traumatized with hard food and utensils.

2 - Large tori can infringe on tongue space, which could impact breathing by forcing the tongue back into the throat. This distalization of the tongue into the throat could then infringe on airway space.

3 - Tori can make it very difficult, if not impossible, to fabricate a partial or full denture over them. In some cases the tori would have to be surgically removed. I would strongly recommend that people with tori have extra good oral hygiene so they do not need partials or dentures.