• Maxillofacial Plastic and Reconstructive Surgery
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• v.19 no.3
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• pp.250-259
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• 1997

The purpose of this study was to evaluate the interrelationship of the soft and hard tissue changes after both maxillary and mandibular anterior segmental surgery in bimaxillary protrusion patients. 11 patients had received both maxillary and mandibular anterior segmental surgery and were investigated radiologically with lateral cephalogram. The results were as follows : 1. The correlation of maxillary hard and soft tissue horizontal changes were relative high. : Coefficient between UIE and Stms was 0.89 (p<0.001). 2. The correlation of mandibular hard and soft tissue horizontal changes were very high, especially at the chin. : Coefficients were over 0.90 (p<0.001) 3. All points were moved superiorly except SLS, LS, Stms. 4. Upper and lower lip convexity to the E-Line were decreased (p<0.001) and postsurgical facial profiles were changed very esthetically.

• The korean journal of orthodontics
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• v.38 no.2
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• pp.83-94
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• 2008

Purpose: The first objective of this study was to compare the upper midface morpholgy, focusing on the soft tissues, between skeletal Class III maloccusion patients with midfacial depression and the norm. The second objective was to estimate and analyze the change in the upper midface soft tissues following surgical correction with maxillary advancement by Lefort I osteotomy and mandibular setback by bilateral sagittal split osteotomy (BSSRO). Methods: The samples consisted of 34 adult patients (15 males and 12 females) with an average age of 21 years, who had severe anteroposterior discrepancy with midfacial depression. These patients had received presurgical orthodontic treatment and surgical treatment which consisted of simultaneous Lefort I osteotomy and BSSRO. Results: The correlation coefficient between changes in maxillary advancement and changes in Or' (soft tissue orbitale) was 0.599 (p < 0.05). Change in maxillary plane angle and vertical change of the maxilla were not correlated with the change in Or' (p < 0.05). The ratio of soft tissue change in Or' to maxillary advancement was 43.57 %, and 81.54 % in Sn. Regression equations between maxillary movement and Or' were devised. The $r^2$ value was 0.476. Conclusions: The majority of measurements in the upper midface in skeletal Class III maloccusions when compared to the norm, showed significant differences. In Class III malocclusion with midfacial depression, maxillary advancement produces soft tissue change in the upper midface.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.23 no.4
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• pp.348-356
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• 2001

The factors related to relapse in 20 skeletal class III patients who performed two-jaw surgery with Le Fort I maxillary osteotomy and bilateral sagittal split ramus osteotomy was investigated. All patients were fixed with miniplate on the maxilla and three screws at each mandible. Cephalograms taken at preoperative, immediate postoperative and 8 months postoperative after surgery were traced and digitized. 1.The horizontal and vertical relapse of maxilla and mandibular chin points was within 1mm postoperatively. Compare to the preceding report concerning the mandibular set-back surgery only group, this reveals two-jaw surgery for mandibular prognathism using rigid fixation is more stable. 2.Although there was no significant relapse tendancy was observed at chin points, the screw tip land-marks moves anterio-superiorly and each side of the screws moved as a one unit. The screw tip points moved similar direction to the masticatory force and this movements might be influenced by the muscular tension to the distal segment of the mandible. 3.According to the regression analysis, the amount of horizontal and vertical movement of mandibular set-back influenced the mandibular relapse. However, direction and amount of maxillary surgical movement did not inf1uenced the maxillary and mandibular relapse.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.6
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• pp.485-491
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• 2009

Postoperative skeletal stability was evaluated in combination of Le Fort I and U-shaped osteotomies for superior repositioning of maxilla in bi-maxillary surgeries in 30 consecutive patients. The fifteen patients underwent Le Fort I osteotomy alone and the other fifteen patients underwent Le Fort I and U-shaped osteotomies. In all patients, the maxilla was first osteomized and fixed with absorbable plates system. A bilateral sagittal split ramus osteotomy (BSSRO) of the mandible was then carried out and fixation was performed using absorbable plates. Maxillo-mandibular fixation with rubber ring was used for two weeks post-operatively in all patients. Lateral cephalograms were obtained pre-operatively, 1 day post-operatively, 6 months after surgery. The changes in anterior nasal spine (ANS), point A, upper incisior (U1), and point of maxillary tuberosity (PMT) were examined. The maxillas in the fifteen patients of both examination group were repositioned nearly in their planned positions during surgery and no significant post-operative changes in the examined points of the maxilla were found. These results suggest that a combination of a Le Fort I and U-shaped osteotomy is a useful technique for reliable superior repositioning of the maxilla. The post-operative change in the maxilla using this combination osteotomy was comparatively stable.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.6
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• pp.559-565
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• 2006

The aim of this study was to evaluate the amount and interrelationship of the soft and hard tissue changes after simultaneous maxillary clockwise rotation and mandibular setback surgery in skeletal class III malocclusion. The sample comprised of 16 adult patients who had anteroposterior skeletal discrepancy. These patients had received presurgical orthodontic treatment and surgical treatment which consisted of Le fort I Osteotomy and bilateral saggital split ramus osteotomy. The presurgical (T1) and postsurgical (T2) lateral cephalograms were evaluated. The computerized statistical analysis was carried out with SPSS/PC program. The results demonstrated a decrease in the vertical dimension in the soft and hard tissue. The nasolabial angle was increased and the mentolabial angle was decreased. The results showed also many statistically significant correlations(p<0.05). The lower lip closely followed the skeletal movement of the B- point in the horizontal plane. The double jaw rotation surgery can afford a good solution to solve the problems of class III malocclusion cases.

• Journal of Dental Rehabilitation and Applied Science
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• v.26 no.3
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• pp.359-371
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• 2010

Facial asymmetry has been found with a higher frequency (70~84%) in skeletal class III malocclusion patients. Anticipating the poor prognosis of prosthesis due to malocclusion, occlusal stability must be obtained by orthodontic treatment. Moreover, orthodontic surgery would be needed in some severe cases for better functional and esthetic results. The orthognathic surgery is performed on one jaw or two jaw depending on the results of facial diagnosis. Genioplasty may change the vertical, horizontal, sagittal position of chin by osteotomy or augmentation using implants, also. This case is about a 24 year-old male patient who visited our clinic to solve the facial asymmetry and mandibular prognathism. Skeletal class III malocclusion, maxillary canting and menton deviation to left by 13 mm were detected. Multiple ill-fitting prostheses, unesthetic maxillary anterior prostheses, and several dental caries were found. After pre-operative orthodontic treatment, Le-Fort I osteotomy, sagittal split ramus osteotomy, genioplasty, right mandibular angle augmentation were done for the correction of jaw relation and asymmetry. By diagnostic wax-up after post-operative orthodontic treatment, maxillary full mouth rehabilitation and mandibular posterior restorations were planned out. For better result, clinical crown lengthening procedure was done on #11, 12 and implant was placed on left mandibular first molar area. The patient was satisfied with the final prostheses. Because of his high caries risk, long-term prognosis will depend on the consistent maintenance of oral hygiene and periodic follow-up.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.5
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• pp.407-412
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• 2011

Purpose: The purpose of the present study was to evaluate the postoperative skeletal stability of two-jaw surgery (Le Fort I osteotomy and bilateral sagittal split ramus osteotomy) via surgery first orthodontic treatment (SFOT) in class III malocclusion. Methods: Thirty-two patients who had two-jaw surgery via SFOT were included in this study. Serial lateral cephalograms were obtained before (T0), immediately after (T1), and six months after (T2) surgery. Twelve variables were measured for horizontal and vertical skeletal stability as well as for dental change. All measurements were evaluated statistically by a paired t-test ($P$ <0.05). Results: The mean skeletal changes were $0.1{\pm}2.5$ mm at point A and $-12.0{\pm}7.4$ mm at the pogonion. The mean horizontal relapse was 11.6% at the pogonion, and the mean vertical surgical changes included an upward displacement of $2.1{\pm}7.1$ mm and a forward displacement of $1.4{\pm}4.6$ mm at the pogonion. Upper incisor inclination decreased after surgery and was maintained at T2, and lower incisors were proclined from T1 to T2 by postsurgical orthodontic treatment. Conclusion: Postoperative skeletal stability of two-jaw surgery via surgery first orthodontic treatment in class III malocclusion was clinically acceptable.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.2
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• pp.137-143
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• 2011

Purpose: Orthognathic surgery is required in patients with severe skeletal disharmony and facial asymmetry, which results in functional and esthetic improvement. Recently, bimaxillary surgery has become generalized. Establishment of the occlusal plane among several other factors included in the surgery plan is a major consideration for the diagnosis and treatment plan and it is also an important factor for postoperative stability. Methods: In this study, we assessed postoperative stability of occlusal plane, B-point, and pogonion point on 20 patients who underwent two-jaw surgery in the Chosun Dental Hospital from 2000 to 2007. Preoperative and postoperative states and at least a one year postoperative follow-up were compared. Results: The postsurgical relapse volume of the occlusal plane to the SN plane and the FH plane was $-0.26{\pm}2.8^{\circ}$ and $-0.44{\pm}3.29^{\circ}$, respectively and after two-jaw surgery, the stability of occlusal plane was maintained. The horizontal relapse degree was $0.85{\pm}0.46$ mm and $0.76{\pm}0.48$ mm, respectively, and the vertical relapse degree was $1.16{\pm}0.36$ mm and $1.13{\pm}0.71$ mm of the B point and the Pogonion point at the time after minimal 1 year. Conclusion: The vertical relapse amount was shown to be slightly larger than the horizontal relapse amount.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.2
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• pp.148-156
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• 2007

Purpose: The aim of this study is the changes of upper respiratory airway space in patients with mandibular prognathism after 2-jaw orthognathic surgery in patients with skeletal classs III malocclusion. Method: We measured the lines between selected upper airway landmarks on lateral cephalometric x-ray films of skeletal class III 64 persons who had not been operated yet, were 6 months after operation. The test subjects were divided into 3 groups according to maxillary movement, as follows; maxillary advancement (MA) group, maxillary posterior impaction (MPI) group, maxillary posterior impaction and superior repositioning (MPI+MSR) group. Result: In this study, nasopharyngeal airway space in MPI+MSR group was significantly increased after operation (p<0.05). Oropharygeal and hypopharyngeal airway space in MA group and MPI group were significantly decreased after operation (p<0.05). From hyoid bone to anterior mandible point distance in MA group and MPI group were significantly decreased after operation (p<0.05). Conclusion: Oropharygeal and hypopharyngeal airway space were influenced more by mandibular set-back than maxillary movement. Maxillary movement surgery as well as mandibular setback surgery should be taken into consideration in order to minimize symptoms related to obstructive sleep apnea syndrome after operation.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.1
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• pp.21-26
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• 2006

Considering the skeletal class III malocclusion that complains of mandibular prognathism, there have been some studies of the mandibular change for comparing the changes of pre operative with post operative state. Nowadays it is common to do the orthognathic 2-jaw surgery for the correction of the maxillary deficiency, the post operative stability and the esthetics. We compare and analyze the changes of soft tissue around the nose and the lip with the changes in the direction and the amount of maxilla. Patients who were diagnosed as maxillofacial deformity and received orthognathic surgery of both jaws at Yongdong Severance hospital from 2001 through 2003 were included in this study. Their lateral cephalograms were analyzed, and the post operative change of hard tissue and soft tissue were studied. Upon analyzing the preoperative cephalograms and 6 month post operative cephalograms, there were significant in the vertical change of Labialis superius(Ls) and Stomion(Stm) in soft tissue in relation to the vertical change of skeletal landmarks (Anterior Nasal Spine, Subspinale, Prosthion, Incision Superious). In addition, there were no significance in horizontal movement of the skeletal landmarks among groups. In terms of hard tissue landmarks, group 3(maxillary posterior impaction and advancement surgery group) showed significantly greater change in the vertical movement of Anterior Nasal Spine(ANS), Subspinale(A), Prosthion(Pr), and Incision Superious(Is) compared with other groups. In terms of soft tissue change, group 3 showed more significant change in the vertical movement of Ls and Stm. This study calculated the changes of the skeletal and soft tissue landmarks in order to act as a guide in planning and performing the surgery and as a reference in predicting the postoperative change of facial appearance.