Aesthetics of the malar-mandibular area High cheekbones and a distinct mandibular contour characterize the appearance of East Asian persons, especially those of Korean and Japanese descent. In the West, such features are valued, and these areas are frequently enhanced for optimal aesthetic appearance. However, because of the more delicate topography of the typical Asian face, zygomas and mandibular angles that are overly prominent upset the balance, rendering the face overly flat, wide, and square.
In addition to its undesirable aesthetic appearance, in some East Asian cultures the prominent zygoma and mandibular angle have traditionally been associated with negative personal characteristics. On occasion, this can lead to difficulty finding a spouse or discrimination in the workplace.
For these reasons, Asian patients who might hesitate to have other types of surgery are willing to undergo reductive correction of these areas.
Surgeons must recognize that patients seeking bone-contouring surgery, as in other aesthetic surgeries performed on Asian persons, have a desire to improve their appearance; they are not attempting to achieve an appearance more typically associated with a western European person. Preservation of ethnicity remains the cornerstone of aesthetic surgery performed on Asian persons. A mistaken presumption on the part of the surgeon that the Asian patient is seeking an appearance more typically associated with a white person will lead to great disappointment for the patient and, eventually, the surgeon.
History of the Procedure:
Malar prominence
Onizuka proposed shaving or burring-down the prominent portions of the zygoma, usually the body, through an intraoral incision. For those persons with a wide arch, Watanabe proposed resecting the arch. Yang accomplished an infracture of the zygoma through an intraoral-preauricular approach.
Baek et al (1991) considered the apparent prominent zygoma in Asian patients to be predominantly a malposition of the zygoma. They proposed a repositioning operation that involves performing an osteotomy at the arch-body junction, performing a second osteotomy at the posterior arch, and repositioning the segment superiorly.
Mandibular angle prominence
Pacific Asian persons frequently have prominence of the mandibular angle and hypertrophy of the masseter muscle. This condition is frequently referred to as benign masseteric hypertrophy, but the relationship of this medical condition, frequently accompanied by pain, to the desires of a patient seeking an aesthetic appearance is not completely clear. Nevertheless, surgical techniques for benign masseteric hypertrophy remain applicable for correction of the prominent mandibular angle. Resection of the lateral portion of the bone, contouring the posterior border of the mandible with and without removal of the masseter muscle, has been performed. The trend has been to perform the procedure through an intraoral approach whenever possible. More recently, the use of botulinum A or B toxin has been reported for the correction of masseteric hypertrophy.
Problem:
Classification of deformities
The zygoma consists of the body and the arch, either of which can be prominent. Most frequently, the defect involves the lateral portion of the body at the origin of the arch. Therefore, this is the area most frequently addressed surgically, reducing the bulk by burring the anterolateral portion of the zygomatic bone. This is followed by creating an osteotomy just lateral to the burred area, at the body, and another osteotomy at the origin of the arch. The intervening segment is then medially mobilized (in-fractured) (Baek, 1991).
Prominence of the zygoma occurs ideally in isolation; thus, correction leads to a balanced, narrower face. However, it also occurs in association with a broad skull base, as observed by Watanabe. Improvement in facial contour is less dramatic in these patients because bitemporal width remains unchanged even after the intermalar distance has been narrowed. These patients should receive appropriate preoperative counseling.
The posterior mandibular angle should be evaluated because correction of the malar area exaggerates any prominence of the mandibular angle. This situation is analogous to the relationship between the nose and chin complex.
Prominent mandibular angle
The mandibular angle can be prominent on the frontal view, lateral view, or both views. The prominence can involve primarily the bone, the masseter muscle, or both. Analysis of the problem by direct examination and by radiographs reveals the problem. The surgical correction is then directed appropriately.
Frequency: Requests for correction of malar and mandibular angle prominence are common in metropolitan areas with large East Asian populations. Occasionally, male patients seeking a sex change may request these operations.
Etiology: The etiology of this condition is unknown.
Pathophysiology: Although the etiology of benign masseteric hypertrophy is usually unknown, masseteric hypertrophy is thought to be due to work hypertrophy, such as in habitual jaw clenching or teeth grinding. Interestingly, benign masseteric hypertrophy is frequently found among Korean persons who favor dried squid, a tough and chewy delicacy.
The etiology of prominent malar bones is more obscure. Although it can occur in isolation, it frequently occurs in conjunction with benign masseteric hypertrophy. According to Baek et al, hyperostosis of the malar bone may occur at the attachment of the masseter muscle, in the same manner as hyperostosis of the mandible.
Clinical: Patients requesting zygoma reduction surgery may simply wish to have a more balanced appearance. East Asian cultures value a small face, and wide cheekbones appear to make the face bigger. In other cases, patients may attribute some misfortune in their life to the zygomatic prominence and wish it corrected for this reason. The patient with a prominent mandibular angle generally seeks aesthetic improvement. A prominent jawline creates a masculine appearance that may be undesirable. Because Asian beauty emphasizes subtlety, a prominent jawline throws off the balance of subtle midfacial features (nose, chin) by overpowering the mid face. Reducing the jawline restores the balance. When it comes to the prominent jawline, patients may have a significant muscle component, bone component, or both.
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