Corrective jaw surgery is commonly done for dentofacial disharmonies that developed due to disproportional growth. As such, most jaw surgery patients are young, ranging from late teens to twenties. However, there is another group of patients whose dentofacial deformities are acquired due to trauma. This can happen when someone trips and falls on his face or it an also be due to sports. More serious deformities can occur through road traffic accidents. The surgeon who does that primary repair of these injuries usually does not have the luxury of doing a thorough discussion with the patient about aesthetics. The patient usually is in pain and just wants to have the injuries treated. Trauma to the face also causes a lot of swelling which obscures the true appearance of the face. As such, the initial treatment of facial injuries may not achieve good aesthetics and function. Corrective jaw surgery may be needed in some cases to rectify the residual deformity.
The assessment of traumatic facial deformities is generally the same as the developmental ones. However, several other factors are critical too. The nature of the accident, ie was it is a car accident, a sports injury, etc. The length of time since the accident also plays a role in the decision making process. The initial surgery that was done will also impact the final treatment options available.
Some of the common problems encountered are:
Surgery:
Depending on the extent of the residual deformity and how badly it affects function, the patient may choose to undergo surgery to correct them or to accept the defects. Corrective surgery is not without risks and the patient needs to be apprised of the downside. Like any other surgery, the benefit must outweigh the risks.
Patients with mis-alignment of the jaws and asymmetry can be managed just like in orthognathic surgery whereby a CT scan is done and the planning done on computer programs. Models of the teeth need to be made and the usual model surgery is done in the laboratory to determine the correct position.
Anterior open bites are a bit more tricky. The usual way to correct anterior open bite is to impact the back of the upper jaw upwards so that the back teeth are repositioned higher, allowing the lower jaw to close. However, in traumatic deformities, the open bite is a result of the shortening of the condylar neck/ramus (vertical part) of the lower jaw and not excessive growth of the back part of the upper jaw. Depending on the overall aesthetic demand, the open can be corrected by impacting the upper jaw like in conventional orthognathic surgery or by lengthening the ramus or reconstructing the condylar neck. The latter option if more complicated but is preferred if the patient wants to restore his facial height to pre-injury dimensions.
The initial trauma may have resulted in loss of bone fragments. In reconstructive surgery of the jaw, bone grafting may be needed to restore the dimensions of the jaws to its original state. Bone is usually taken from the hip bone and grafted to the deficient sites.
Conclusion..
Traumatic deformities can be managed like conventional dentofacial deformities using orthognathic surgery techniques. Without the constraint of time imposed at the initial trauma surgery, a better result can be achieved both functionally and cosmetically during secondary surgery. Some times, reconstructive techniques such as bone grafting are needed to restore normal anatomy and function.