• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.3
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• pp.239-249
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• 2001

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 $6{\sim}10mm$ 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).

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.3
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• pp.218-224
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• 2011

Purpose: The purpose of this study is to evaluate the post-operative skeletal stability after surgical correction of patients with mandibular prognathism by bilateral sagittal split ramus osteotomy (BSSRO) and to evaluate the horizontal relapse tendency after the surgery. Methods: Twenty-six patients with Class III dental and skeletal malocclusion were selected for this retrospective study. Fifteen of them underwent BSSRO for mandibular setback and eleven of them underwent two-jaw surgery (Lefort I and BSSRO). In each patient, lateral cephalometric radiographs were taken pre-operatively, post-operatively within 1 week, and post-operatively after eight months. After tracing of the cephalometric radiographs, various parameters were measured. The analyses were done by linear measurement to evaluate the change in position of hard tissue B point, pogonion and mandibular plan angle by examination on lateral cephalograms. Results: The horizontal relapse rate was 27.1% at B point and 31.6% at pogonion in patients who underwent BSSRO. The horizontal relapse rate of the group where the amount of correction exceeded 10 mm was 25.69% at B point. Conclusion: There were no statistical differences on the magnitude of setback and direction of rotation of the mandible in mandibular stability. There were also no statistical differences between single mandibular surgery and two-jaw surgery for mandibular stability.

• Journal of Yeungnam Medical Science
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• v.12 no.2
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• pp.393-399
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• 1995

Mandibular retrusion showing the facial problem with a marked maxillarry incisors protrusion and chin deficiency, resulting in a highly convex profile is uncommon in Korea.. The large incisor overjet and deep-bite create functional limitations and unpleasing esthetic result. The majority of theses cases are susceptible to correction by orthodontic therapeutic methods. But severe Class II retrognathic cases in which orthodontic treatment alone has not been capable of achieving good results. Orthognathic surgery offers several approaches. In this case, mandibular advancement by bilateral sagittal split ramus osteotomy and augmentation genioplasty has a special surgical problems. The suprahyoid muscle gorup are lengthened if the body of the mandible is surgically repositioned anteriorly. Instability of results and relapse return to original position shoud predicted during post-surgical muscular readjustment.. To maintain maximum correction with this technique, it is suggested that the mandibular body be well rotated forward at time of surgical intervention and overcorrected anteriory as much as possible. So, the authors report the case with review of concerned literature.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.6
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• pp.565-569
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• 2001

A new surgical approach to the area of the infratemporal fossa and parapharyngeal space is described. This approach results in a wide-field exposure of the infratemporal fossa, pterygomaxillary space and parapharyngeal space. We used two osteotomies on the patient's mandible and temporary resection of zygomatic arch for superior margin of tumor. Lower lip splitting was not needed because the incision was started in the frontal scalp, curved in front of and below the external auditary canal, and extended anteriorly to the greater horn of hyoid bone on the neck along a skin crease. We had good results without sacrifice of the facial nerve, mandibular function and sensory supply of the face and oral cavity.

• The korean journal of orthodontics
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• v.40 no.4
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• pp.239-249
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• 2010

Objective: The aim of this study was to identify the expression of nitric oxide synthases (NOS) in the mandibular condyle during mandible advancement by functional appliance and to correlate it with the histologic changes and bone remodeling. Methods: Twenty-four female, 35-day-old Sprague-Dawley rats were randomly divided into 3 experimental groups. In all experimental groups, the mandibles of the rats were kept in a continuous forward position with a fixed bite jumping appliance. The rats were sacrificed on the 3rd, 14th, and 30th days of experiment. More than 2 rats in each group were used for staining. Results: There were no remarkable histologic changes and NOS expression differences in the control group. The most prominent histologic changes occurred in the 14th day experimental group. NOS decreased in the 30th day experimental group. There was increased expression of $NOS_2$ and $NOS_3$ in all experimental groups, comparative to the control group. In all the experimental groups and control group, the expression of $NOS_2$ was greater than that of $NOS_3$. Conclusions: It is postulated that $NOS_2$ and $NOS_3$ in the mandibular condyle might play an important role in bone remodelling of the mandibular condyle.

• The korean journal of orthodontics
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• v.31 no.5 s.88
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• pp.517-523
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• 2001

Titanium miniscrews we being used increasingly as an anchorage for tooth movement, because they ate easy to place and to remove, increase the number of sites available, give minimum strain to patients regarding surgical procedures, and offer uneventful healing alter removal. The use of titanium miniscrews as an orthodontic anchorage has been reported in clinical case reports, but clinicians have experienced screw loosening when using such screws.' To our knowledge, there are no published reports evaluating the stability of miniscrews. Information about the length of miniscrews used in relation to the location is of some importance, as stability will vary depending on bone duality The purpose of this study was to evaluate a variety of Lengths of miniscrews (dimeter: 2mm) which were inserted in maxilla or mandible and to demonstrate in a dog model which miniscrew provides fundamental stability in the jaws. 10 mm long miniscrews in the maxilla and 8mm long: miniscrews in the mandible showed no clinical mobility and retained their position throughout an 8 weeks force (200g) application. The mucosal condition around the screws was healthy in cases in which miniserews were inserted in the alveolar bone between the roots and the head of the screws emerged into the attached gingiva. When the force application was terminated, radiographic analysis revealed neither rent resorption not periodontal pathology around the miniscrews that remained stable during the entire treatment period. This study suggests that if titanium miniscrews with adequate length are properly used depending on the location, they provide sufficient stability for orthodontic anchorage.