## 4 Discussion
When cmAMP is applied to conventional orthognathic surgery with pre-surgical orthodontic treatment, the postsurgical occlusal relationship between the upper and lower teeth should be considered and adjusted compromisingly with overlapping cmAMP in the direction of MSP. Moreover, the need for any auxiliary surgeries like bone grafting, cortical osteotomy, and genioplasty could be reduced if cmAMP was used during surgical planning and simulation because mandible symmetry could be maximized by using cmAMP. Should additive surgery be required, it would be possible to create surgical guides through images expressed in volume discrepancies in color-codes by grafting cmAMP to commercially available 3D software. Among several factors that cause mandibular asymmetry, the different growth rates of the condylar and body units independently occurring are known to be the main etiologic cause for the asymmetry [27; 28; 29]. In this study, only the anterior segment divided by the osteotomy line was compared and analyzed in cases that received orthognathic surgery with IVRO only. If the cause of the mandibular asymmetry is the morphological difference of the condyle or posterior part of the ramus,it is possible to evaluate the asymmetry of the entire mandibular structure stereoscopically, as shown in Figures 1 and 2, such that the technique we introduced here can be applied to each case. In this study, since the anterior part can be easily improved through orthognathic surgery, we focused on the recovery of the anterior part's similarity index before and after surgery. Not only do patients with severe facial asymmetry want corrective orthognathic surgery, but patients with minor or even inexistent asymmetry now also want to receive bimaxillary surgery for improving facial aesthetics. Thus, future studies are needed to investigate whether this new approach of establishing cmAMP may be applied to patients with minor asymmetry who were planning to undergo bimaxillary orthognathic surgery. Conversely, in the case of severe asymmetric patients with a congenital deformity, if the landmark of bilateral structures, such as the mental foramen used in this study, are well maintained and detected, we can apply cmAMP to diagnose patients, help to plan surgery, and evaluate the results after surgery. However, in growing patients, even if they perform orthognathic surgery with cmAMP, the left and right structures can be changed through continuous growth. The fact that this study, as such, was only conducted among adults remains a limitation. In addition, asymmetric patients may need care throughout their lifetime. Furthermore, to date, most studies on the changes in soft tissue following bimaxillary surgical correction of facial asymmetry remain inconclusive [5; 30; 31]. Since soft tissue changes are difficult to predict with simple mathematical formulas or calculations, we have been forced to focus on improving the most predictable hard tissue in our study. However, even though it remains difficult to accurately predict the change in soft tissue according to the change in hard tissue through orthognathic surgery using CBCT images, the amount of change in the volume of the soft tissue of the corresponding area according to the change of hard tissue volume is intuitively calculated and evaluated by applying the technique we introduced. If measured, the predictability of soft tissue changes can be improved. To maximize the similarity index of soft tissue after surgery through the application of cmAMP in future studies, it is necessary to reflect the various factors (soft tissue tension, gender, age, weight, vertical skeletal pattern, etc.) of each patient that affect the prediction of soft tissue in the algorithm rather than using simple measurement points [32].