What Is Maxillary Tuberosity?

The maxillary tuberosity is a large, rounded area on the outside surface of the maxillary bones — or the bones of the upper jaw — in the area of the posterior teeth, the molars in the back of the mouth. The maxillary tuberosity is hard and is covered by tough gum tissue. Problems can result in this part of the mouth during dental procedures such as tooth extractions.

The tuberosity is a major landmark in the upper jaw, on both sides of the top dental arch. A person will find this landmark situated just behind and above the third molar tooth, which also is known as a wisdom tooth. The posterior superior alveolar nerves usually pierce the back surface of the maxillary tuberosity. The superior alveolar nerves essentially are the nerves that cause a person to have sensation in his or her second and third molar teeth, as well as in most of the roots of the first molar tooth. The structure is permanent, as even if a dentist extracts all of an individual’s upper teeth, the maxillary tuberosity remains.

Latin terms have led to the creation of the name of the rounded prominence in the top part of the mouth. For instance, the term tuber in “tuberosity” is the Latin term for bump or lump. Meanwhile, maxilla in “maxillary” is derived from the Latin word “mala,” which means “cheek.” The Latin word macerare also means “to chew,” and this potentially was the foundation for the term “maxilla” as well.

A fracture of the maxillary tuberosity is an important medical issue. This type of fracture should be avoided because this bony projection helps a person’s upper dentures to remain in place. In addition, a fracture in this area eventually can lead to maxillary sinusitis, an inflammation of the maxillary sinuses due to viruses, fungi, and bacteria flowing from the mouth into the nose.

Several situations make a fracture in the bone behind and above the third molar tooth likely, and fixing this area often involves splinting. A molar tooth that is situated in the area by itself, excessive force used to remove the tooth, or an irregular number of roots on the tooth all can cause a maxillary tuberosity fracture. If a fracture does happen, an oral surgeon typically splints the area with archbars to make the mobile areas of the bone stable for four to six weeks.