Skeletal relapse is known as a complication following orthognathic surgery of mandibular prognathism and occurring during intermaxillary fixation period. Therefore relapse of teeth and skeleton during intermaxillary fixation period is considered as a important problem of orthognathic surgery. In this study, cephalolateral radiographs taken at pre-operation, immediate post-operation and after release of intermaxillary fixation were measured for evaluation of dental and skeletal relapse in 30 cases. The cases were classified as screw fixation group and plate fixation group, then we compared magnitude of dental and skeletal changes of each group. The results were as follows 1. The 1 SN angle increased at immediate post-operation with a mean value of 0.12 degrees and at intermaxillary fixation period with a mean value of 0.43 degrees (p>0.05). 2. The l .. MP angle decreased with a mean value of 0.14 degrees at immediate post-operation and with a mean value of 1.28 degrees during intermaxillary fixation period but there were not significant difference(p>0.05). 3. There were not significant difference in magnitude of dental position changes between screw fixation group and plate fixation group(p>0.05). 4. Gonial angle increased with a mean value of 0.62 degrees during intermaxillary fixation period. Each group showed changes of gonial angle during intermaxillary fixation period but there were not significant difference(p>0.05).
Mandible* ; Orthognathic Surgery ; Prognathism ; Recurrence ; Skeleton ; Tooth*

To evaluate the relapse pattern and long-term stabilities depanding on surgical methods following orthognathic surgery of Cl III patients, the author selected 24 subjects(10 male, 14 female) operated by SSRO and 26 subjects(10 male, 16 female) operated by IVRO. Each subject took four lateral cephalograms: just before surgery(Tl), within 48hrs after surgery(T2), 4-8 wks after surgery(T3), 6 month or more after surgery(T4), and the landmarks were digitized. The differences of relapse patterns in each interval between two groups were compared and the significance of correlation among the variables of each group was tested The obtained results are as follows; 1. Horizontal early relapse was forward movement of mandible in SSRO group, as compared to the backward movement in IVRO group, and there was a statistical significance between the two groups. 2. Vertical early and late relapses were decreases in anterior facial height in both groups and there was no statistical significance between the two groups. 3. There was a statistical significance in negative correlation between mandibular hornontal late relapse and surgical change of articular angle in SSRO group. 4, There was a statistical significance in negative correlation between amount of mandibular set-back and mandibular horizontal early relapse in both groups.
Humans ; Male ; Mandible ; Orthognathic Surgery* ; Recurrence*

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

surgery because their positional change may leads to postoperative skeletal relapse as well as TM joint problem. Various condylar positioning devices, therefore, have been introduced and utillzed in orthognathic surgery. Even though most of them provided us with improvement of surgical results, we also found some problems including limited indication, etc. For more accurately repositioning the maxilla and the mandible and its wide versatility, a newly designed maxilla and condylar positioning device based on the fixed part of cranium is introduced.]]>
Joints ; Mandible ; Maxilla ; Orthognathic Surgery ; Recurrence ; Skull

OBJECTIVETo investigate the method for mandible osteotomy in order to make the mandible of various square face appear harmony.

METHODSAccording to different types of the mandible, mandible angle osteotomy was performed in combination with mandible edge, mandible half ring osteotomy or chin augmentation.

RESULTSA total of 312 cases have been treated since 1996. In this series, mandible angle and mandible edge osteotomy was performed in 200 cases; only mandible edge osteotomy in 23; mandible half ring osteotomy in 15, chin sharpening in 9, chin augmentation with autogenous bone implantation, in 32. Postoperative follow-up of 150 cases for 1-12 months showed that the satisfactory rate was 97%.

CONCLUSIONIntegrated mandible osteotomy can make the square face look natural and nice-looking.

Sagittal split ramus osteotomy (SSRO) is one of the surgical techniques used to correct mandibular deformities. In order to prevent many surgical anatomical problems, we observed the anatomical structures related to SSRO. In dry mandibles of Koreans, lingular tips were located somewhat posteriorly and superiorly on the mandibular ramus. On the coronal sections of mandible, the mean cortical width of facial cortex was increased toward the ramus region while the lingual cortex was thinnest in the ramus region. On the same sections, all the fusion points of the buccal and lingual cortical plate were located above the mandibular lingula and beneath the mandibular notch. So, performing the SSRO on Koreans, medial horizontal osteotomy should be done through the superior aspect of the mandibular lingula. The cut line is extended 5-8 mm posterior to the mandibular lingula to preserve sufficient cortical width to strengthen the involved osseous segments and reduce possible surgical complications.
Anatomy, Artistic ; Human ; Human ; Mandible/surgery* ; Mandible/anatomy & histology* ; Medical Illustration ; Osteotomy/methods*

Defects were created in the mandible of a rabbit model whereby the right side was implanted with hydroxyapatite (HA) while the left side was left empty to act as control. Both the implant and control sites were evaluated clinically and histologically at 4,12,20,22 weeks. Decalcified sections were studied under confocal laser scanning microscope. No reactive cells were evident microscopically in all sections. There was bone ingrowth as early as 4 weeks when viewed by the topographic method. Enhancement of osteoconduction was evident by the presence of abundant capillaries, perivascular tissue and osteoprogenitor cells of the host. At 22 weeks, the implanted defect showed mature bone formation filling almost the whole field. This study demonstrated that the dense HA exhibits excellent biocompatibility as noted by the complete absence of reactive cells. It also promotes osteoconduction.
*Bone Substitutes ; *Hydroxyapatites ; Mandible/pathology ; Mandible/*surgery ; *Materials Testing ; Osseointegration/physiology

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

The purpose of this study was to evaluate the patterns of skeletal changes of proximal and distal segments after one jaw surgry and two jaw surgery with posterior impaction using SSRO on mandible in order to determine the skeletal origin of relapse and compare the stability of surgical methods in anterior open bite. The points and lines from lateral cephalometrics were measured before, after surgery, and at least 6-month follow up period. And then, the positional change of the proximal and distal segment were evaluated respectively. The results obtained were as follows; In cases of two jaw surgery, the results were stabler because they had less relapse factors. In cases of one jaw surgery, the value of APD were increased but it didn't relapse to the original value. Both of proximal and distal segments were responsible for the relapse tendency. But in one jaw surgery, the rotation of proximal segment was more responsible, and in two jaw surgery, the rotation of distal segment was.
Follow-Up Studies ; Jaw ; Mandible* ; Open Bite ; Orthognathic Surgery* ; Recurrence

The purpose of this study is to evaluate the relationship of the factors which could be influenced by orthognathic surgery especillay SSRO. We measured the amounts of the maximum opening, lateral movements, maximum velocity and pattern of mandibular path during the opening and closing of mandible at the following times ; preoperative, 1 month after operation, 6 months after operation respectively using MKG. And the results were compared according to the categorized subgroups. Following results were obtained : 1. The change of the amounts of mandibular lateral movement and maximum opening velocity were statistically different between male and female (p<0.05), but the others were not. 2. According to the method of operation, there was no difference in the change of the mandibular movements between the group of SSRO and SSRO plus LeFort I osteotomy (p>0.05). 3. According to the amounts of mandibular movement, the recovery of left lateral movement of the group of 6~10mm was better than the other groups (p<0.05). 4. In the frontal pattern of the opening and closing of the mandible, the complex deflected type (F5), simple deflected type (F4), complex deviated type (F3), simple deviated type (F2), straight type (F1) were obtained in order at the time of preoperative, simple deflected type, simple deviated type, complex deviated type, straight type, complex deflected type in order at the time of 1 month after surgery, and the result at the time of 6 months after surgery was the same with that of the time of preoperative. In the sagittal pattern, non-coincident type (S2) was predominant at the time of preoperative, and coincident type (S1) was predominant at the time of 1 month after surgery. After 6 months, the result was also the same with that of the preoperative in sagittal pattern. 5. There was not a statistical difference in the change of the mandibular movement between group of presence of the preoperative TMJ symptoms and non-presence group (p>0.05). 6. There was not a statistical difference in the change of the mandibular movement between repositioning device applied group and non-applied group (p>0.05). 7. Sixty three percents of the patients who had preoperative TMJ symptoms were improved after surgery and preoperative TMJ symptoms were more improved after operation in the repositioning device non-applied group statistically (p<0.05).
Female ; Humans ; Male ; Mandible ; Orthognathic Surgery* ; Osteotomy ; Temporomandibular Joint