OBJECTIVE: To aid the development of a frontal image simulating program, we evaluated the soft tissue frontal changes in relationship to movement of hard tissue with orthognathic surgery of facial asymmetry patients. METHODS: Preoperative and postoperative frontal cephalograms and frontal view photographs of 45 mandibular surgery patients with facial asymmetry were obtained in a standardized manner. Vertical and horizontal changes of hard tissue and soft tissue were measured from cephalograms and photographs, respectively. Soft tissue change in result to hard tissue change was then analyzed. RESULTS: Both vertical and horizontal correlation analysis showed a weak relationship between the changes. Hard tissue points that were picked for 1:1 mean ratio with soft tissue points did not show any significant relevance. For each soft tissue change, regressive equation was formulated by stepwise multiple regression analysis, and the equation for soft tissue Menton was most reliable in predicting changes. Both vertical and horizontal hard tissue changes were used together in prediction of vertical or horizontal soft tissue change. CONCLUSIONS: The results suggest that computerized image simulation using regression analysis may be of help for prediction of soft tissue change, while 1:1 mean ratio method is not useful.
Facial Asymmetry ; Humans ; Orthognathic Surgery

Condylar hyperplasia is a pathologic condition showing 3-dimensional skeletal hyperplasia of the mandible. The reason for condylar hyperplasia is not yet known, but the effects of hormone, trauma, infection, genetics, fetal condition, and hypervascularity are known as possible reasons. When we diagnose a patient as having condylar hyperplasia, it is important to decide if it is in progress or not. Treatment for facial asymmetry due to condylar hyperplasia are decided accordingly, including condylectomy, that is removal of growth site of the affected condyle, and conventional orthognathic surgery only or condylectomy with orthognathic surgery after the completion of growth. Therefore, it is important to determine the growth state of condylar hyperplasia in treatment stability. This is verified through bone scan and regular check-ups with 3D CT or PA cephalogram. This case report introduces an improved case of facial asymmetry with condylectomy together with orthognathic surgery.
Facial Asymmetry ; Humans ; Hyperplasia ; Mandible ; Orthognathic Surgery

facial asymmetry. There were 40 patients whose mandibular prognathism with/without facial asymmetry were treated with orthognathic surgery from March 2002 to October 2003. The Group A(n=20) had a mandibulo-facial asymmetry over 6mm menton deviation in cephalogram PA and the Group B(n=20) had a mandibular prognathism. The preoperative frontal photograph, cephalogram PA and three dimensionalcomputed tomography(divided in hard tissuse image and soft tissue image) of two group was evaluated NDA(nasal deviation angle) and MDA(mandibular deviation angle). The NDA was statistical difference between asymmetry Group A and symmetry Group B(p<0.01), and was deviated in affected side of asymmetry. The MDA were also statistical difference between Group A and Group B(p<0.01), however the measurements of MDA between the frontal photograph, 3D-CT and cephalogram PA were similar to each others. The low correlation of NDA between frontal photograph and cephalogram PA in Group A and B demonstrate that we couldn't assess nasal deviation in cephalogram It could be concluded that patients with mandibulo-facial asymmetry have a nasal deviation and clinician must remember this fact when they assess and treat patients.]]>
Facial Asymmetry ; Humans ; Orthognathic Surgery ; Prognathism

In orthognathic surgery, precise analysis and diagnosis are essential for successful results . In facial asymmetric patient, traditional 2D image analysis has been used by lateral and P-A Cephalometric view, Skull PA, Panorama, Submentovertex view etc. But clinicians sometimes misdiagnose because they cannot find exact landmark due to superimposition, moreover image can be magnified and distorted by projection technique or patient's skull position, when using these analysis and method. For overcome these defects, analysis by using of 3D CT has been introduced. In this way we can analysis precisely by getting the exact image free of artifact and finding exact landmark with no interruption of superimposition. So we want to review of relationship between various skeletal landmarks of mandible or cranial base and facial asymmetry by predictable analysis using 3D CT. We select the cases of the patients who visited our department for correction of facial asymmetry during 2003-2007 and who were taken image of 3D CT for diagnosis. 3D CT images were reconstructed to 3D image by using V-Work program (Cybermed Inc., Seoul, Korea). And we analysis the relationship between facial asymmetry and various affecting factor of skeletal pattern. The mandibular ramus hight difference between right and left was most affecting factor that express facial asymmetry. And in this research, there was no relationship between cranial base and facial asymmetry. The angulation between facial midline and mandibular ramus divergency has significant relationship with facial asymmetry
Artifacts ; Facial Asymmetry ; Humans ; Mandible ; Orthognathic Surgery ; Skull ; Skull Base

PURPOSE: This study aimed to investigate the deviation of landmarks from horizontal or midsagittal reference planes according to the methods of establishing reference planes. MATERIALS AND METHODS: Computed tomography (CT) scans of 18 patients who received orthodontic and orthognathic surgical treatment were reviewed. Each CT scan was reconstructed by three methods for establishing three orthogonal reference planes (namely, the horizontal, midsagittal, and coronal reference planes). The horizontal (bilateral porions and bilateral orbitales) and midsagittal (crista galli, nasion, prechiasmatic point, opisthion, and anterior nasal spine) landmarks were identified on each CT scan. Vertical deviation of the horizontal landmarks and horizontal deviation of the midsagittal landmarks were measured. RESULTS: The porion and orbitale, which were not involved in establishing the horizontal reference plane, were found to deviate vertically from the horizontal reference plane in the three methods. The midsagittal landmarks, which were not used for the midsagittal reference plane, deviated horizontally from the midsagittal reference plane in the three methods. CONCLUSION: In a three-dimensional facial analysis, the vertical and horizontal deviations of the landmarks from the horizontal and midsagittal reference planes could vary depending on the methods of establishing reference planes.
Facial Asymmetry ; Humans ; Orthognathic Surgery ; Tomography, X-Ray Computed

When we establish treatment planning of facial asymmetry, we must predict each asymmetrical element that will be changed upon coronal, axial, sagittal plane. At the visual point, prediction of the change of coronal plane is most important. It is important difference between Rt. and Lt. mandibular angle belonging to posterior coronal plane, as well as anterior coronal plane, such as upper and lower incisor, or midline of chin point. Several methods for control bulk of mandibular angle are additional angle shaving after osteotomy, grinding contact area between proximal and distal segment for decrease the volume, or bone graft for increase the volume. But, at the point of bimaxillary surgery, transverse position of posterior maxilla is an important factor for control it. So, we would report transverse movement of posterior maxilla for decrease asymmetry on the posterior coronal plane of face, that is, asymmetry of mandibular angular portion.
Chin ; Facial Asymmetry* ; Incisor ; Maxilla* ; Orthognathic Surgery* ; Osteotomy ; Transplants

The purpose of this study is to evaluate the amount of correction and relapse after orthognathic surgery in patients with facial asymmetry and prognathism by means of the frontal cephalogram. Out of twenty prognathism patients who had been diagnosed as having skeletal facial asymmetry in need of orthognathic operation at our institute during last 6 years, only thirteen patients with pre-existing pre-operative(T0), immediate postoperative (T1) and long term follow up(T2) frontal cephalograms were included in the study. The population was divided according to the kind of surgical operation and severity of asymmetry. The midline sagittal reference line (MSR) was drawn and four basic landmarks were marked on the frontal T0, T1 and T2 cephalograms. Radiographic facial asymmetry was found most obviously in the lower jaw(Deviation from MSR: 2.21mm at ANS, 8.34mm at menton). Facial asymmetry was corrected to minimal degree(1.34 at menton) with orthognathic procedures. On long-term follow up, the correction of deviation was maintained as 1.98mm. The relapse rate was 24.1% at menton. The contributing factor was searched and the amount of asymmetry correction and the amount of prognathism correction proved to have statistical significance (p<0.05). In conclusion, asymmetry could be corrected with orthognathic procedures, which could be maintained with minimal degree of relapse. However, in preoperative planning, the degree of relapse should be considered to maximize the aesthetic outcome.
Facial Asymmetry* ; Follow-Up Studies ; Humans ; Orthognathic Surgery* ; Prognathism* ; Recurrence*

Lip canting is associated with facial asymmetry, and is one of the most challenging problems in surgical correction of facial deformities. The author corrected lip canting using bioabsorbable devices during orthognathic surgery. Soft tissue suspension procedures were performed on four patients with facial asymmetry. Lip lines improved for all patients. Over an observation period of five years, no complications were noted, nor did any late relapse develop. Furthermore, as time past, the effect of the Endotine suspension procedure increased probably due to induction of fibrosis on surrounding soft tissues.
Congenital Abnormalities ; Facial Asymmetry ; Fibrosis ; Humans ; Lip* ; Orthognathic Surgery* ; Recurrence

Facial asymmetry can be classified into the rolling-dominant type (R-type), translation-dominant type (T-type), yawing-dominant type (Y-type), and atypical type (A-type) based on the distorted skeletal components that cause canting, translation, and yawing of the maxilla and/or mandible. Each facial asymmetry type represents dentoalveolar compensations in three dimensions that correspond to the main skeletal discrepancies. To obtain sufficient surgical correction, it is necessary to analyze the main skeletal discrepancies contributing to the facial asymmetry and then the skeletal-dental relationships in the maxilla and mandible separately. Particularly in cases of facial asymmetry accompanied by mandibular yawing, it is not simple to establish pre-surgical goals of tooth movement since chin deviation and posterior gonial prominence can be either aggravated or compromised according to the direction of mandibular yawing. Thus, strategic dentoalveolar decompensations targeting the real basal skeletal discrepancies should be performed during presurgical orthodontic treatment to allow for sufficient skeletal correction with stability. In this report, we document targeted decompensation of two asymmetry patients focusing on more complicated yaw-dependent types than others: Y-type and A-type. This may suggest a clinical guideline on the targeted decompensation in patient with different types of facial asymmetries.
Chin ; Facial Asymmetry* ; Humans ; Mandible ; Maxilla ; Orthognathic Surgery ; Tooth Movement

BACKGROUND: Mandibular motion tracking system (ManMoS) has been developed for orthognathic surgery. This article aimed to introduce the ManMoS and to examine the accuracy of this system. METHODS: Skeletal and dental models are reconstructed in a virtual space from the DICOM data of three-dimensional computed tomography (3D-CT) recording and the STL data of 3D scanning, respectively. The ManMoS uniquely integrates the virtual dento-skeletal model with the real motion of the dental cast mounted on the simulator, using the reference splint. Positional change of the dental cast is tracked by using the 3D motion tracking equipment and reflects on the jaw position of the virtual model in real time, generating the mixed-reality surgical simulation. ManMoS was applied for two clinical cases having a facial asymmetry. In order to assess the accuracy of the ManMoS, the positional change of the lower dental arch was compared between the virtual and real models. RESULTS: With the measurement data of the real lower dental cast as a reference, measurement error for the whole simulation system was less than 0.32 mm. In ManMoS, the skeletal and dental asymmetries were adequately diagnosed in three dimensions. Jaw repositioning was simulated with priority given to the skeletal correction rather than the occlusal correction. In two cases, facial asymmetry was successfully improved while a normal occlusal relationship was reconstructed. Positional change measured in the virtual model did not differ significantly from that in the real model. CONCLUSIONS: It was suggested that the accuracy of the ManMoS was good enough for a clinical use. This surgical simulation system appears to meet clinical demands well and is an important facilitator of communication between orthodontists and surgeons.
Dental Arch ; Dental Models ; Facial Asymmetry ; Jaw ; Orthognathic Surgery* ; Splints