Facial asymmetry is generally the norm, not the exception. The same may be said to be true for any paired body part. Few people have identical facial halfs but most such asymmetries are minor and essentially undetectable. With the asymmetry becomes more than minor (greater than five millimeters or more), however, it may become apparent to more than just the casual eye.

One of the most common reasons for facial asymmetry is the mandible or lower jaw. In my experience, I consider it the most likely facial bone to develop differences between the two sides during growth. This most likely is because of its hinged or joint attachments (TMJ) to the skull where jaw growth is highly influenced by condylar development. Any injury, even minor, to the condyle during growth can cause bone developments differences between the two sides.

When the lower jaw is not symmetrically developed, it can be quite apparent with obvious facial asymmetry and a potential malocclusion. (poor bite) More frequently, however,  the face and jaw may be asymmetric but one’s occlusion has good interdigitation. There are many known causes of mandibular asymmetry including a superior altered cranial base (craniosynostosis, torticollis, deformational plagiocephaly), condylar deformities (fractures, hyperplasia, hemifacial microsomia, arthritic degeneration) and external compressive deformation from overlying tumors causing a mass effect.

Most commonly, however, I see mandibular-based facial asymmetries in adults which do not have a clearly identifiable cause. Regardless of the reason, known or unknown, the diagnosis only matters from the standpoint of understanding where and how the mandible is asymmetric. While 3-D CT scans make great pictures and clearly show the problem, I find that a panorex film is just as helpful. It allows for tracing and precise measurements of the vertical height of the ramus, the differences in the inferior border of the mandible from side to side, and the symmetry of the two chin halfs.

When mandibular asymmetry exists with a bite discrepancy or significant cant to the face, strong consideration should be given to a combined treatment plan of orthodontics and corrective maxillary and mandibular osteotomies. This will produce by far the best long-term solution. However, for those patients that do not want or are not capable of going through this program or for more minor asymmetries, a camouflage treatment can be done.

Camouflage treatments for any form of facial asymmetry is largely based on using bone implants for augmentation or removing bone for reduction.  For the short posterior (back part) of the mandible, the use of jaw angle implants can be very useful to made it wider or longer…often both are needed. Those jaw angle implants which extend or wrap around the lower border are particularly useful as well as more stable. When the ramus is too long, jaw angle and inferior border ostectomies (bone removal) can be done to better match the other side. Both approaches are done intraorally.

When the asymmetry involves the chin implants are not usually the best option. Cutting and leveling the chin bone (one side reduction or expansion) is usually more effective and a better long-term solution.

Significant correction of mandible-based facial asymmetries can be done by a combination of jaw angle and chin manipulations. Choosing the best options can be done through a good facial analysis and patient discussion as well as a tracing assessment of a panorex.

Dr. Barry Eppley

http://www.eppleyplasticsurgery.com

http://www.ologyspa.com

Clarian North Medical Center, Carmel, Indiana

Clarian West Medical Center, Avon, Indiana

Indianapolis

Occipital plagiocephaly is a well known congenital malformation of the back of the head marked by an oblique slant to the main axis of the skull. It is commonly corrected today by the early institution of either static or dynamic cranial orthotics or helmets. In rare cases if the skull is significantly deformed and does not respond to external molding influences, cranial reshaping can be successfully done.

Plagiocephaly is well known to affect how the face develops. What happens in the back of the skull will influence how the front of the skull and face looks. This occurs in a diametrically opposite manner. The side that is flat on the back of the head will be protrusive on the front….and vice versa. Even in cases where helmet therapy or even surgery has made a well rounded back of the head, the face may still show some of the residual effects as it develops resulting in facial asymmetry. When plagiocephaly goes untreated or was not adequately treated at a young age, this facial asymmetry may become quite apparent.

The facial asymmetry that results from a plagiocephalic influence appears as that of a ‘twisted’ face if one is looking from above. This is apparent by misaligned ears (the ear on the affected side may be pulled forward and down and be larger then the unaffected ear) and facial asymmetry, with the more forward side of the face having a fuller forehead, brow bone, and cheek. The jawbone will be tilted and one’s occlusion (bite) may have a cant to it. There may be differences in the position and shape of the jaw angles and the chin may be deviated toward the ‘weaker’ or more retrusive side.

When the facial asymmetry is very severe, complete facial bone repositioning incorporating orthodontics and multiple jaw orthognathic surgery is needed. But most of such facial asymmetry that I see in my Indianapolis plastic surgery practice is more mild and in late adolescence or adulthood. Patients are looking for less major methods for improving their facial asymmetry.

When one considers improving facial asymmetry, a careful analysis of the face must be done to determine exactly where the imbalances are. Of even greater importance is input from the patient as to which facial prominences they consider to be the good or the bad side. This is very important because weak areas can be built up with implants which is most commonly done because it is easier. But reduction of bone can be done in certain facial areas if they are too prominent.

Options in facial asymmetry correction include from top to bottom: forehead/brow augmentation, forehead/brow reduction, cheek and orbital implants, jaw angle augmentation or reduction, inferior border mandibular ostectomies, and chin osteotomies or implants. Such an array of procedures requires thoughtful and careful preoperative planning. When more than one of these is done during the operation (which is most common), the effects of facial rebalancing can be quite significant. In my experience, at least two or three facial areas are treated at the same time to get the best result.

 While complete or perfect facial symmetry is not obtainable in any case, significant camouflaging of the facial bony asymmetries can be made. Such surgical improvement provides great psychological relief to the facial asymmetry patient and can usually be achieved in a single operation.   

Dr. Barry Eppley

http://www.eppleyplasticsurgery.com

http://www.ologyspa.com

Clarian North Medical Center, Carmel, Indiana

Clarian West Medical Center, Avon, Indiana

Indianapolis