Mandibular torus, or mandibular tori in plural form, is a thickening or growth that occurs in the inner part of the mandible. It is classified as an abnormality of the oral cavity. Mandibular torus is also known as torus mandibularis, with the plural form being tori mandibularis.

The mandible is the bone that not only forms the human skull’s lower jaw, but also secures the lower teeth. For this reason, it is also called the inferior maxillary bone. The mandible forms the floor of the oral cavity. The torus, or outgrowth, usually appears near the bicuspids or premolars.

On most occasions, the condition actually occurs as tori instead of just one bony elevation, appearing at both the left and right sides of the mandible. Regarding gender, mandibular torus occurs a little more frequently in males than females, and in terms of age group, more than 90 percent of the cases involve adult patients. Also, the condition is more common among Asians and Inuit Eskimos.

Mandibular torus is a slow-growing condition. It also has the tendency to fluctuate in size. In some cases, where there is more than one protrusion, the tori can grow to the point of touching each other.

Medical researchers have come up with some causes for mandibular torus. A factor is bruxism, a disorder characterized by teeth grinding and jaw clenching during sleep. Other researchers attribute it to genetics or stress-related factors involving the teeth.

Physicians generally do not deem mandibular tori as significantly threatening to overall health, or prescribe treatment. The elevations, however, might present difficulty to people who wear dentures. In such cases, dental surgery can be performed to remove some of the mandible. If the teeth still have stresses, however, the torus could recur.

Mandibular torus is commonly associated with a similar condition called mandibular palatinus. The latter condition appears on the palate, which is the roof of the mouth, as compared to the mandible, which forms the floor of the mouth. Also, mandibular palatinus appears on the mid-line of the harder half of the palate, a bony section at the front of the mouth’s roof called the hard palate. It occurs more frequently than mandibular torus, accounting for up to 60 percent of mandibular growth-related cases.