Torus mandibularis
Encyclopedia
Torus mandibularis (or mandibular torus (pl. mandibular tori) in English) is a bony
growth
in the mandible along the surface nearest to the tongue
. Mandibular tori are usually present near the premolar
s and above the location of the mylohyoid muscle
's attachment to the mandible. In 90% of cases, there is a torus on both the left and right sides, making this finding an overwhelmingly bilateral condition.
The prevalence of mandibular tori ranges from 5% - 40%. It is less common than bony growths occurring on the palate
, known as torus palatinus
. Mandibular tori are more common in Asian and Inuit populations, and slightly more common in male
s. In the United States, the prevalence is 7% - 10% of the population.
It is believed that mandibular tori are caused by several factors. They are more common in early adult life and are associated with bruxism
. The size of the tori may fluctuate throughout life, and in some cases the tori can be large enough to touch each other in the midline of mouth. Consequently, it is believed that mandibular tori are the result of local stresses and not solely on genetic
influences.
Mandibular tori are usually a clinical finding with no treatment necessary. It is possible for ulcers to form on the area of the tori due to trauma. The tori may also complicate the fabrication of dentures
. If removal of the tori is needed, surgery
can be done to reduce the amount of bone, but the tori may reform in cases where nearby teeth still receive local stresses.
Bone
Bones are rigid organs that constitute part of the endoskeleton of vertebrates. They support, and protect the various organs of the body, produce red and white blood cells and store minerals. Bone tissue is a type of dense connective tissue...
growth
Exostosis
An exostosis is the formation of new bone on the surface of a bone. Exostoses can cause chronic pain ranging from mild to debilitatingly severe, depending on where they are located and what shape they are....
in the mandible along the surface nearest to the tongue
Tongue
The tongue is a muscular hydrostat on the floors of the mouths of most vertebrates which manipulates food for mastication. It is the primary organ of taste , as much of the upper surface of the tongue is covered in papillae and taste buds. It is sensitive and kept moist by saliva, and is richly...
. Mandibular tori are usually present near the premolar
Premolar
The premolar teeth or bicuspids are transitional teeth located between the canine and molar teeth. In humans, there are two premolars per quadrant, making eight premolars total in the mouth. They have at least two cusps. Premolars can be considered as a 'transitional tooth' during chewing, or...
s and above the location of the mylohyoid muscle
Mylohyoid muscle
The mylohyoid muscle is a muscle running from the mandible to the hyoid bone, forming the floor of the oral cavity. It is named for its two attachments, with the prefix "mylo" coming from the Greek word for "molar". These muscles are mesodermal in origin...
's attachment to the mandible. In 90% of cases, there is a torus on both the left and right sides, making this finding an overwhelmingly bilateral condition.
The prevalence of mandibular tori ranges from 5% - 40%. It is less common than bony growths occurring on the palate
Palate
The palate is the roof of the mouth in humans and other mammals. It separates the oral cavity from the nasal cavity. A similar structure is found in crocodilians, but, in most other tetrapods, the oral and nasal cavities are not truly separate. The palate is divided into two parts, the anterior...
, known as torus palatinus
Torus palatinus
Torus palatinus [palatinus torus in English] is a bony protrusion on the palate. Palatal tori are usually present on the midline of the hard palate...
. Mandibular tori are more common in Asian and Inuit populations, and slightly more common in male
Male
Male refers to the biological sex of an organism, or part of an organism, which produces small mobile gametes, called spermatozoa. Each spermatozoon can fuse with a larger female gamete or ovum, in the process of fertilization...
s. In the United States, the prevalence is 7% - 10% of the population.
It is believed that mandibular tori are caused by several factors. They are more common in early adult life and are associated with bruxism
Bruxism
Bruxism is characterized by the grinding of the teeth and typically includes the clenching of the jaw. It is an oral parafunctional activity that occurs in most humans at some time in their lives. In most people, bruxism is mild enough not to be a health problem...
. The size of the tori may fluctuate throughout life, and in some cases the tori can be large enough to touch each other in the midline of mouth. Consequently, it is believed that mandibular tori are the result of local stresses and not solely on genetic
Genetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....
influences.
Mandibular tori are usually a clinical finding with no treatment necessary. It is possible for ulcers to form on the area of the tori due to trauma. The tori may also complicate the fabrication of dentures
Dentures
Dentures are prosthetic devices constructed to replace missing teeth, and which are supported by surrounding soft and hard tissues of the oral cavity. Conventional dentures are removable, however there are many different denture designs, some which rely on bonding or clasping onto teeth or dental...
. If removal of the tori is needed, surgery
Torus removal surgery
Torus removal surgery is a surgical procedure performed to remove one or more extra protuberances of bone either on the palate or the mandible. Although such segments of extra bone are not harmful in any way in and of themselves, their presence may present a problem for those patients who require...
can be done to reduce the amount of bone, but the tori may reform in cases where nearby teeth still receive local stresses.