Direct physical examination is the most important process to evaluate the patient’s problems and establish a surgical plan. Clinical photos are necessary, as is radiologic examination including frontal view, submentovertex view, and Waters’ view. A computed tomography (CT) scan with 3D reconstruction is also helpful to evaluate the shape of the zygomatic complex. The key variables to consider are the volume and position of the zygomatic body and the bizygomatic width. The amount of ostectomy required during the surgery is determined according to the volume of the zygomatic body. A wider resection of the zygomatic body should be planned when the volume is large. However, excessive reduction may cause a flat or deficient look. Therefore, maintaining an adequate volume of the zygomatic body in the anteroposterior dimension and transverse plane after the surgery is essential.

To make the midfacial width narrow, the lateral margin of zygoma should be trimmed or moved medially. If the outer margin of zygoma is placed laterally, the amount of osteotomy and medialization should be maximized. The maximal malar projection (MMP) point is the most protruded portion of the outer contour of zygomatic complex in the basal three-quarters view. If osteotome line is placed lateral to the MMP point, or the reduction of the zygomatic body is performed only by shaving, this point stays unchanged although the outer margin of the zygomatic body is narrowed. It results in an unnatural, two-dimensional appearance. Therefore, making adequate projection and positioning MMP point at ideal position is the key for desirable postoperative result.

The ideal MMP point may vary among different ethnicities and subjective favors; however, the following are two simple methods of determining the ideal position of the MMP (Fig. 16.3) generally.

The surgical approach and technique for reduction malarplasty was introduced in 1983. Onizuka et al. [4] introduced chiseling and/or shaving method to reduce the protruding portion of the malar bone through intraoral incision. After that, various surgical techniques have been devised, such as bone shaving, infracture of the zygomatic arch [5], and osteotomy/ostectomy of the zygomatic body [2, 6–9]. Bone shaving method is the simplest and easily practicable method when it is used for localized protrusion of a zygomatic body. However, excessive shaving of the zygomatic body may cause exposure of cancellous bone, and it can result in postoperative irregularity [10] as cancellous bone is absorbed unpredictably. Thus, the amount of shaving is limited, and the overall size of the zygomatic body cannot be reduced only with shaving method. Furthermore, shaving method cannot be applied to the zygomatic arch as thickness of arch is not enough to be reduced through shaving [11]. The in-fracture technique [5] is one of the useful methods in reducing the protrusion of the zygomatic arch. Surgeons usually conduct osteotomy of the zygomatic arch, avoiding a full-depth cut and maintaining the continuity of the periosteum (greenstick) [10] and pushing the zygomatic segments medially. Its major advantages are simplicity and speed; however, it carries the risk of an uncontrolled amount of in-fracturing in the zygomatic arch, and it has a limited effect on a prominent zygomatic body. An L-shaped osteotomy of the zygomatic body is the preferred method for patients with moderate to severe malar protrusion due to wide zygomatic arch and prominent body. An L-shaped osteotomy is made in the anterior part of the zygomatic body, and a separate osteotomy is made in the posterior part of the zygomatic arch. With or without removal of bone [6], a zygomatic segment is moved to the desired position and fixed with wires or plates and screws. The L-shaped osteotomy technique can change both the zygomatic body and arch and has the advantage of controlling the degree of reduction as well as the shape after reduction. As patients usually desire change in the zygomatic body and arch, L-shaped osteotomy is currently the most frequently used and preferred method in zygomatic reduction (Fig. 16.4).

The approach for reduction malarplasty can be simply divided into two types: the external approach (coronal incision, temporal incision, preauricular incision) and the intraoral approach. The external and the intraoral approaches have their respective advantages and drawbacks [11]. As zygomatic reduction developed from the treatment of zygomatic fracture, the coronal approach was first used to expose the entire zygomatic body and arch. However, it requires a long operation time, and it may cause bleeding and visible scarring. The intraoral approach has the advantage of hidden scars, limited bleeding, and short operation time. However, it provides limited operative exposure, resulting in difficult osteotomy, limited space for fixation, and the risk of infraorbital nerve injury. Side effects include cheek drooping due to wide dissection and volume reduction, which can be avoided by minimizing the dissection. The osteotomized segment should be rigidly fixed and postoperative elastic dressing provided to prevent cheek drooping. The intraoral approach can be used solely; however, it is usually combined with preauricular incision or temple incision to minimize the dissection and the possibility of cheek drooping.