Mandibular surgery is surgery performed to the lower jaw in order to move and reshape the bones. This process of bone moving is called osteotomy. Generally, this type of surgery is done to correct growth problems in the jaw, such as undergrowth, overgrowth, or open space. Surgery of this nature can also be performed to correct an asymmetry of the jaw, which occurs when one side of the jaw grows differently than the other.
Overgrowth of the jaw, more technically called prognathia, causes the jaw to protrude beyond the upper portion. It results in an underbite, where the bottom teeth rest on top of the upper teeth. Aside from cosmetic issues, this condition can cause various problems with a person's speech and ability to chew. To correct this condition, mandibular surgery usually involves the removal of a portion of the jawbone. This will effectively pull the lower jaw back and allow it to line up with the upper jaw.
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When a person suffers from an undergrowth of the jaw, otherwise known as retrognathia, the lower jaw and chin are receded and set back from the upper jaw, resulting in a pronounced overbite and sloping appearance. This condition can cause jaw pain and can affect a person's ability to chew. In extreme instances, it can also impact a person's ability to breathe properly. Mandibular surgery corrects this condition by adding pieces of bone onto the jaw so as to push it forward and line it up with the upper jaw. The bone that is grafted onto the jaw can be artificial or can be taken from elsewhere on a person’s body.
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There are instances when a person’s jaw grows unevenly, causing an asymmetric appearance. This asymmetry can also be corrected by mandibular surgery. Depending upon the nature of the asymmetry, additional bone might be grafted into the lower jaw, or certain sections of bone might be removed. Ultimately, the goal is to have the upper and lower jaw lined up so that a person does not experience pain, difficulties with chewing, or breathing problems such as sleep apnea.
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Whether mandibular surgery is undertaken to correct an overgrowth, undergrowth, or asymmetry, it is done under general anesthesia. The incision is usually made inside a person’s mouth. Depending upon the extent of the procedure, a person may have limited use of his or her jaw anywhere from two to six weeks. A person undergoing mandibular surgery can expect to have facial swelling as well, which generally subsides as the surgical site heals.