Tori and Exostoses

A torus (plural “tori”) is a harmless growth of bone. Tori commonly found in the mandible (lower jaw) are called tori mandibularis. Tori occurring on the palate (roof of the mouth) are called torus palatinus.

Tori or exostoses are asymptomatic, bony protuberance of mature bone.  They are characterized by slow growing, hard swelling usually present on the hard palate (roof of the mouth), along the inner portion of the mandible, or the outer posterior aspects of the upper and lower jaw.  Bony growth found on the roof of the mouth are called maxillary tori.  Mandibular tori are found on the inner aspect of the mandible around the canine to premolar region.  Exostoses occurs on the outer portion of the upper and lower jaw.

The characteristic swelling or growth of the hard tissue can occur in young adults or in the adult population.  It is thought to be an inherited condition.  Cause of tori growth and the precipitating factors that initiate or stimulate growth are not known. The mucosa covering the tori can be very thin and prone to injury during consumption of food with hard texture.

Maxillary tori, or palatal tori, are usually found in the center of the hard palate (roof of the mouth) and can show both symmetrical or irregular pattern.  The palatal tori are more prevalent in Asians, Native Americans, and Eskimos. The prevalence of maxillary tori in the general population is about 20 to 25 %.  It usually appears during the second or third decade of life, although it may occur at any age.

Mandibular tori are more prevalent in African American and Asian populations. The overall incidence of mandibular tori in the United States is about 6 to 12 %.  It has been suggested that parafunctional habits may play a role in development of the condition.  These lesions are asymptomatic and slow growing.  Usually occur during the second or third decade of life.  In extreme cases, bony plates growing from the inner portion of the mandible can come to a point of contact. This can impede movement of the tongue.

Exostoses are single or multiple bony nodules that can occur on the buccal or outer portion of the alveolar bone (bone supporting the teeth). The classification is done strictly by the location of the lesions.  Usually found bilaterally in the posterior regions of the upper and lower jaw.

Treatment of these lesions is usually not necessary because they are asymptomatic and slow growing.  May need to be excised for prosthetic considerations, if dentures will be fabricated, or if the lesions interfere with speech, function, or oral hygiene.  Removal is usually completed under local anesthesia by a general dentist or an oral surgeon.