• The Journal of the Korean dental association
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• v.51 no.6
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• pp.322-329
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• 2013

Among the occlusal discrepancies, maxillary transverse deficiency is quite common in several reasons. The reasons are comprised of maxillary hypoplasia, thumb sucking habits, non-syndromic palatal synostosis and syndromal patients including cleft patients. Orthodontic treatment is used routinely to correct a deficiency in young patients while it has limitations for a skeletally mature patient. Surgical treatments help provide effective maxillary expansion to correct a deficiency in adults. Surgical methods can be categorized to segmental Le Fort I osteotomy and surgically assisted rapid maxillary expansion(SARME). Both methods seem successful but each method would have its own indication. We give a review on transverse maxillary deficiency and two surgical methods.

• Proceedings of The Korean Cleft Lip And Palate Association
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• 2002.05a
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• pp.35-35
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• 2002

• Maxillofacial Plastic and Reconstructive Surgery
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• v.35 no.2
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• pp.82-87
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• 2013

Purpose: This study evaluated postoperative maxillary stabilities in patients with skeletal Class III malocclusion who were taken both maxillary advancement surgery and mandibular retrusive surgery, using Le Fort I osteotomy, through three-dimensional computed tomography. Methods: We selected 14 patients who were taken postoperative three-dimensional computerized tomography at the time before surgery, immediately after surgery, six months after surgery among the patients undergone both maxillary advancement surgery using Le Fort I osteotomy and mandibular retrusive surgery using bilateral sagittal split ramus osteotomy. We measured and compared the vertical distance of A-point and posterior nasal spine (PNS), the horizontal distance of A-point and PNS in transverse plane and coronal plane of the three-dimensional reconstructed images, respectively. Results: In transverse plane, the distance difference between immediately after surgery ($S_1$) and immediately before surgery ($S_0$) of A-point was $-0.04{\pm}1.80$ mm, $S_2$ and $S_0$ was $-0.15{\pm}1.69$ mm, and between $S_1$ and $S_2$ was $0.11{\pm}0.58$ mm. There were no significant differences between these data (P>0.05). In transverse plane, the distance between $S_1-S_0$ of PNS was $-3.87{\pm}2.37$ mm, $S_2-S_0$ of PNS was $-3.79{\pm}2.39$ mm, and $S_1-S_2$ of PNS was $-0.08{\pm}0.18$ mm. There were significant differences between these data (P<0.05). In coronal plane, the distance between $S_1-S_0$ of A-point was $3.99{\pm}0.86$ mm, $S_2-S_0$ was $3.57{\pm}1.09$ mm, and $S_1-S_2$ was $0.42{\pm}0.42$ mm. There were significant differences between these data (P<0.05). In coronal plane, the distance between $S_1-S_0$ of PNS was $3.82{\pm}0.96$ mm, $S_2-S_0$ was $3.43{\pm}0.91$ mm, and $S_1S_2$ was $0.39{\pm}0.49$ mm. There were significant differences between these data (P<0.05). In transverse plane, it was estimated that PNS has no statistical postoperative stability in the same direction. In coronal plane, it was estimated that both A-point and PNS had no statistical postoperative stability (P<0.05). Conclusion: Clinically, the operation plan needs to take into account of the maxillary relapse.

• The korean journal of orthodontics
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• v.51 no.5
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• pp.321-328
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• 2021

Objective: To examine the accuracy of computer-aided intraoperative navigation (Ci-Navi) in bimaxillary orthognathic surgery by comparing preoperative planning and postoperative outcome. Methods: The study comprised 45 patients with congenital dentomaxillofacial deformities who were scheduled to undergo bimaxillary orthognathic surgery. Virtual bimaxillary orthognathic surgery was simulated using Mimics software. Intraoperatively, a Le Fort I osteotomy of the maxilla was performed using osteotomy guide plates. After the Le Fort I osteotomy and bilateral sagittal split ramus osteotomy of the mandible, the mobilized maxilla and the distal mandibular segment were fixed using an occlusal splint, forming the maxillomandibular complex (MMC). Real-time Ci-Navi was used to lead the MMC in the designated direction. Osteoplasty of the inferior border of the mandible was performed using Ci-Navi when facial symmetry and skeletal harmony were of concern. Linear and angular distinctions between preoperative planning and postoperative outcomes were calculated. Results: The mean linear difference was 0.79 mm (maxilla: 0.62 mm, mandible: 0.88 mm) and the overall mean angular difference was 1.20°. The observed difference in the upper incisor point to the Frankfort horizontal plane, midfacial sagittal plane, and coronal plane was < 1 mm in 40 cases. Conclusions: This study demonstrates the role of Ci-Navi in the accurate positioning of bone segments during bimaxillary orthognathic surgery. Ci-Navi was found to be a reliable method for the accurate transfer of the surgical plan during an operation.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.6
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• pp.404-412
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• 2012

Purpose: The purpose of this study was to evaluate postsurgical facial hard tissue stability after orthognathic surgery with/without posterior impaction in skeletal class III malocclusion patients, and to evaluate the horizontal relapse tendency, according to changes in anteroposterior discrepancy and occlusal planes. Methods: Ninety patients, who had undergone orthognathic surgery in Pusan National University Dental Hospital, were enrolled in this study. Three main groups were classified as follows: Thirty patients underwent mandibular setback bilateral sagittal split ramus osteotomy (BSSRO) only (BSSRO group, BG); another thirty patients underwent mandibular setback BSSRO and Le Fort I osteotomy with posterior impaction (posterior impaction group, PG); and another thirty patients underwent mandibular setback BSSRO and Le Fort I osteotomy without posterior impaction (non-posterior impaction group, NPG). Preoperative (T0), immediate postoperative (T1) and six-month follow-up period (T2) lateral cephalograms were taken, and various parameters were measured. The analyses were done by linear and angular measurements between T0-T1 and T1-T2, to evaluate postsurgical facial hard tissue stability. Results: Mean horizontal relapse rates were distributed from 11.81% to 19.08%, and there were significant postsurgical changes (0.52 mm~2.44 mm) at the B point in all 3 groups. But, there were no statistical differences on relapse rate among BG, PG and NPG patients. Conclusion: In this study, the postsurgical stabilities of BSSRO and Le Fort I osteotomy with/without posterior impaction in skeletal class III malocclusion patients were acceptable. There were no significant statistical differences in mandibular stability according to changes in anteroposterior discrepancy and occlusal planes.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.4
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• pp.264-271
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• 2011

Purpose: This study evaluated retrospectively the postsurgical facial hard tissue profile of a Le Fort I osteotomy with/without posterior impaction and rigid internal fixation to correct mandibular prognathism. After observing a difference between the two groups, this measurement was used to prepare a treatment plan for 2-jaw surgery. Patients and Methods: Thirty patients who had undergone orthognathic surgery in Pusan National University Dental Hospital were enrolled in this study. Fifteen patients were treated using a Le Fort I osteotomy with posterior impaction and mandibular setback bilateral sagittal split ramus osteotomy, and the other fifteen patients were treated without posterior impaction. The preoperative (T0), immediate postoperative (T1) and six-month follow-up period (T2) cephalograms were taken and difference between T1-T0 and T2-T2 was analyzed. Results: Both groups was FH-ABp, SNB and ANB showed significant changes in the measurement, whereas only the posterior impaction group showed a change in the SN-U1, occlusal plane, posterior facial height, surgical movement difference from the L1 and B-point. There was no significant statistical change between the immediate postoperative (T1) and six-month follow-up (T2) hard tissue analysis in the two groups. Conclusion: A Le Fort I osteotomy with posterior impaction is considerable for patients with a flat occlusal plane angle, large posterior facial height, prominent B-point, pogonion and labioversed incisal inclination if the indications are well chosen.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.25 no.4
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• pp.324-329
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• 1999

The facial esthetics are much affected by nasal changes due to especially its central position in relation to facial outline and so appropriately evaluated should be the functional and esthetic aspects of the nose associated with the facial appearance. Generally, a maxillary surgical movement is known to induce the changes of nasolabial morphology secondary to the skeletal repositioning accompanied by muscular retraction. These changes can be desirable or undesirable to individuals according to the direction and amount of maxillary repositioning. We investigated the surgical changes of bony maxilla and its effects to nasal morphology through the analysis of the lateral cephalogram in the Le Fort I osteotomy. Subjects were 10 patients(male 2, female 8, mean age 22.3 years) and cephalograms were obtained 2 weeks before surgery(T1) and 6 months after surgery(T2). The surgical maxillary movement was identified through the horizontal and vertical repositioning of point A. Soft-tissue analysis of the nasal profile was performed employing two angles: nasal tip projection(NTP), columellar angle(CA). Also, alar base width(ABW) was assessed directly on the patients with a slide gauge. The results were as follows; 1. Both anterior and superior movement above 2mm of maxilla rotated up nasal tip above 1mm. Either anterior or superior movement above 2mm of maxilla made prediction of the amount & direction of NTP changes difficult. Especially, a correlation between horizontal movement of maxilla and NTP rotated-up was P<0.01. 2. Both much highly anterior and superior movement of maxilla is accompanied by more CA increase than either highly. Especially, the correlation between horizontal movement of maxilla and CA change was P<0.05. 3. Anterior and/or superior movement of maxilla was accompanied by the unpredictable ABW widening. 4. The amount of changes of NTP, CA, and ABW is not in direct proportion to amout of anterior and/or superior movement of maxilla. 5. Nasal morphologic changes following Le Fort I osteotomy are affacted by not merely bony repositioning but other multiple factors.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.35 no.5
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• pp.316-324
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• 2013

This case report describes the treatment of a 23-year-old woman who had lip protrusion with gummy smile and mentalis muscle strain. Orthognathic surgery was performed in conjunction with orthodontics. Minimum dental decompensation was performed with presurgical orthodontics followed by an anterior segmental osteotomy for the majority of dental decompensation. Counterclockwise rotation of the maxillomandibular complex was applied by LeFort I osteotomy, and bilateral sagittal split ramus osteotomies with anterior segmental osteotomy to achieve overall facial balance. The active treatment period was 15 months. Stable occlusion and skeletal relationship were observed after a 10-month follow-up period.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.40
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• pp.37.1-37.7
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• 2018

Background: Fibrous dysplasia (FD) is characterized by the replacement of normal bone by abnormal fibro-osseous connective tissue and typically treated with surgical contouring of the dysplastic bone. When dysplastic lesions involve occlusion, not only is surgical debulking needed, orthognathic surgery for correction of dentofacial deformity is mandatory. However, the long-term stability of osteotomized, dysplastic bone segments is a major concern because of insufficient screw-to-bone engagement during surgery and the risk of FD lesion re-growth. Case presentation: This case report reviewed two patients with non-syndromic FD that presented with maxillary occlusal canting and facial asymmetry. Le Fort I osteotomy with recontouring of the dysplastic zygomaticomaxillary region had been performed. The stability of osseous segments were favorable. However, dysplastic, newly formed bone covered the previous plate fixation site and mild bony expansion was observed, which did not influence the facial profile. Including the current cases, 15 cases of orthognathic surgery for FD with dentition have been reported in the literature. Conclusion: The results showed that osteotomy did not appear to significantly reduce the long-term stability of the initial fixation insufficiency of the screw to the dysplastic bone. However, based on our results and those of the others, long-term follow-up and monitoring are needed, even in cases where the osteotomized segment shows stable results.

• Archives of Plastic Surgery
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• v.44 no.1
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• pp.19-25
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• 2017

Background Numerous condylar repositioning methods have been reported. However, most of them are 2-dimensional or are complex procedures that require a longer operation time and a highly trained surgeon. This study aims to introduce a new technique using a condylar repositioning plate and a centric relation splint to achieve a centric relationship. Methods We evaluated 387 patients who had undergone surgery for skeletal jaw deformities. During the operation, a centric relation splint, intermediate splint, final centric occlusion splint, and condylar repositioning plate along with an L-type mini-plate for LeFort I osteotomy or a bicortical screw for bilateral sagittal split ramus osteotomy were utilized for rigid fixation. The evaluation included: a physical examination to detect preoperative and postoperative temporomandibular joint dysfunction, 3-dimensional computed tomography and oblique transcranial temporomandibular joint radiography to measure 3-dimensional condylar head movement, and posteroanterior and lateral cephalometric radiography to measure the preoperative and postoperative movement of the bony segment and relapse rate. Results A 0.3% relapse rate was observed in the coronal plane, and a 2.8% relapse rate in the sagittal plane, which is indistinguishable from the dental relapse rate in orthodontic treatment. The condylar repositioning plate could not fully prevent movement of the condylar head, but the relapse rate was minimal, implying that the movement of the condylar head was within tolerable limits. Conclusions Our condylar repositioning method using a centric relation splint and miniplate in orthognathic surgery was found to be simple and effective for patients suffering from skeletal jaw deformities.