• Journal of Korean Academy of Oral and Maxillofacial Radiology
• /
• v.7 no.1
• /
• pp.39-42
• /
• 1977

Authors have obserbed a rare case of unilateral hypertrophy occured in the left mandibular condyle of 25 years old man. In the serial roentenograms, Authors have drawn following conclusions. 1. The patients face is markedly asymmetrical. This asymmetry consisted of an elongation and widening of the left mandibular ramus, neck and head of condyle which pushed the chin to the other side. 2. Left mandibular angle is flattened and mandibular inferior border is lower than right. 3. In the relationship of the left posterior teeth, severe mesioocclusion is occured.

• Restorative Dentistry and Endodontics
• /
• v.39 no.1
• /
• pp.45-50
• /
• 2014

Ambiguity in the root morphology of the mandibular second molars is quite common. The most common root canal configuration is 2 roots and 3 canals, nonetheless other possibilities may still exist. The presence of accessory roots is an interesting example of anatomic root variation. While the presence of radix entomolaris or radix paramolaris is regarded as a typical clinical finding of a three-rooted mandibular second permanent molar, the occurrence of an additional mesial root is rather uncommon and represents a possibility of deviation from the regular norms. This case report describes successful endodontic management of a three-rooted mandibular second molar presenting with an unusual accessory mesial root, which was identified with the aid of multiangled radiographs and cone-beam computed tomography imaging. This article also discusses the prevalence, etiology, morphological variations, clinical approach to diagnosis, and significance of supernumerary roots in contemporary clinical dentistry.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
• /
• v.20 no.2
• /
• pp.201-210
• /
• 1990

The purpose of this study was to observe the relationship between mandibular asymmetry and Temporomandibular Disorders by means of the cephalometry using the posteroanterior cephalogram and the submentovertex cephalogram which were taken in 35 Temporomandibular Disorder patients and 35 normal persons ranged from 20S to 30S. The results were as follows: 1. The angulation which was formed by the median line with the ANS-Menton line (MAP) was greater in patients group and there was statistically significant difference. 2. The angulation which was formed to the median line with the Menton-Odontoid process tip line (MES), the difference of the distances from the center of the posterior surface of the both condyles to the most anterior point of the chin (DD), the difference of the distances from the center of the both condyles to the horizontal reference line (DE), the difference of the angulations which were formed by the both condyles axes with the horizontal reference line (DCE), the difference of the lengths of the both condyles (CL) and the difference of the widths of the both condyles (DW) were greater in patients group and there were statistically significant differences. There was reversed correlation between MAP and the difference of the distances from the 3. bilateral points of the lateral margin of the both zygomaticofrontal sutures to the at the lateral inferior margin of the both antegonial protuberances in mandible (DH). There was reversed correlation between MES and DD, DE, DCE. 5. There was correlation between MAP and MES.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.16 no.1
• /
• pp.51-62
• /
• 1994

The sagittal split osteotomy of the mandibular ramus is a common procedure which has been used in the correction of mandibular deformities for a few decades. Although the technical improvements have increased the reliability and stability of SSRO procedure, the postoperative relapse is imperative and clinically more significant than any other complication. One of the major causes of the relapse is due to the displacement of the proximal segment during SSRO procedure, which is well documented in the literature. Therefore it is important to preserve the original position of the proximal segment during SSRO proced and maxillofacial fixation period. In the case of mandibular asymmetry, if one side of mandible is advanced and the other side of mandible is setback during SSRO procedure, the proximal segment in the advancement site will rotate laterally and the proximal segment in the setback site will rotate medially. For the prevention of the lateral rotation or flaring of the proximal segment in the advancment site. we deliberately fracture the posterior protion of the distal segment in green-stick fashion during SSRO procedure, and there is no need to fix the fractured lingual segment. We fix the two osteotomized bony segments in the buccal cortex area rigidly with adjustable monocortical plates and screws. During SSRO procedure the lingual fracture technique was applied to nine patients with severe mandibular asymmetry who underwent orthognathic surgery in our hospital since march, 1992. These clinical experiencies enable us to find the lingual fracture technique has the following advantages. 1. The proximal segment is displaced minimally. 2. The osteotomized bony segments are contacted intimately. 3. The postoperative relapse and the healing period are decreased.

• The korean journal of orthodontics
• /
• v.53 no.4
• /
• pp.219-231
• /
• 2023

Objective: This study aimed to clarify differences in the positions of cone-beam computed tomography (CBCT) landmarks according to different midsagittal planes (MSPs) in patients with skeletal Class III facial asymmetry. Methods: Pre-treatment CBCT data from 60 patients with skeletal Class III were used. The patients were classified into symmetric (menton deviations of < 2 mm) or asymmetric (menton deviations of > 4 mm) groups. Six MSPs were established based on previous studies, and three-dimensional analyses were performed for the planes in both the groups. The measurement outcomes were compared statistically. Results: A statistically significant interaction (p < 0.01) was observed between MSPs and facial asymmetry. No significant differences were observed among MSPs in the symmetric group. However, significant differences in linear measurements were identified among MSPs in the asymmetric group. Specifically, the upper facial MSP revealed both maxillary and mandibular transverse asymmetries. On the other hand, anterior nasal spine (ANS)-associated MSP could not identify maxillary asymmetry. Furthermore, the menton deviation was approximately 3 mm lower when estimated using the ANS-associated MSP than that using upper facial MSP. Conclusions: The choice of MSP can significantly affect treatment outcomes while diagnosing patients with asymmetry. Therefore, care should be taken when selecting MSP in clinical practice.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.32 no.5
• /
• pp.447-453
• /
• 2010

The hemifacial microsomia is characterized by variable underdevelopment of the craniofacial skeleton, external ear, and facial soft tissues. So, patients with hemifacial microsomia have an occlusal plane canting and malocclusion with facial asymmetry. Distraction osteogenesis (DO) with an intraoral or extraoral device is a technique using tension to generate new bone with gradual bone movement and remodeling. DO has especially been used to correct craniofacial deformities such as a hemifacial microsomia, facial asymmetry, and mandible defect that could not adequately be treated by conventional reconstruction with osteotomies. It has a significant advantage to lengthen soft and hard tissue of underdeveloped site without bone graft and a few complication such as nerve injury or muscle contracture. A 13-years old girl visited our clinic for the chief complaint of facial asymmetry. She had a left hypoplastic maxilla and mandible, occlusal plane canting and malocclusion. We diagnosed hemifacial microsomia and lanned DO to lengthen the affected side. Le Fort I osteotomy, left mandibular ramus and symphysis osteotomy were performed. The internal distraction devices fixed with screw on maxillary and mandibular ramus osteotomy sites. External devices were adapted to lower jaw for DO on symphysis osteotomy site and to upper jaw for rapid maxillary expansion (RME). At 7days after surgery, distraction was started at the rate of 1mm per day for 13days, and after 4months consolidation periods, distraction devices were removed. Simultaneous multiple maxillo-mandibular distraction osteogenesis with RME resulted in a satisfactory success in correcting facial asymmetry as well as occlusal plane canting for our hemifacial microsomia.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.34 no.6
• /
• pp.622-627
• /
• 2008

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

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.33 no.1
• /
• pp.55-61
• /
• 2011

Conventional slinding genioplsty has the risk of mental nerve injury after operation and difficult to correct vertical asymmetry of chin. So, authors propose a new genioplasty to correct asymmetry of chin. Switching genioplasty is a modification method of conventional genioplasty. Between mandibular right and left canine, osteotomy line of triangular shape make until mandibular lower border. In large side, osteotome line of wedge shape is added to reduction. After osteotomy, segment of wedge shape was separated from chin. Distal segment was rotated to reduction side. Because of rotation of distal segment, space is made in opposite side. Seperated segement of wedge shape from large side is switched this space to fill. So, stability of distal segment is achieved. Authors applied to swiching genioplasty the patients who was remained the chin asymmetry after both sagittal split ramus osteotome was done because mandible asymmetry. After operation, patient and operator were satisfied with excellent esthetic results without any other complication. The switching genioplasty is effective surgical technique for chin asymmetry because it has more advantages than conventional sliding genioplasty. First, other donor side does not need for bone graft. Second, the switching genioplasty can reduce infection, bone resroption, dehiscence, capsular contraction after allograft. Third, have little mental nerve damage. Forth, anteroposterior correction is possible. Fifth, operation time is less than other genioplasty for chin asymmetry.

• The korean journal of orthodontics
• /
• v.39 no.1
• /
• pp.18-27
• /
• 2009

Objective: The purpose of this study was to understand the differences in masseter muscle(MM) between the shifted and non-shifted sides in facial asymmetry patients, and the changes shown by MM after mandibular surgery. Methods: Pre- and post-operative CT scans were performed on 12 Class III patients with facial asymmetry who were treated by intraoral vertical ramus osteotomy and 10 subjects with normal occlusion. Using the V-works 4.0 program(Cybermed, Seoul, Korea), 3-dimensional images of the mandible, and MM were reconstructed, and evaluated. Results: In the asymmetry group, the MM angle between the shifted and non-shifted sides was only significantly different(p<0.05). Compared with normal occlusion, the asymmetry group showed a significantly smaller volume and maximum cross-sectional area in both sides of MM(p<0.05). After mandibular surgery, the angle of MM(p<0.01) and differences in angle between the shifted and non-shifted sides of MM(p<0.05) were significantly decreased. The thickness in the maximum cross-sectional area was significantly increased(p<0.01). After surgery, MM in facial asymmetry patients was similarly changed to those in the normal occlusion group except for widths. Conclusions: MM in facial asymmetry was definitely different from those in normal occlusion. However, this study suggests that MM changed symmetrically in conjunction with the mandible after proper mandibular surgery.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.38
• /
• pp.18.1-18.9
• /
• 2016

Background: The aim of this study was to examine the relationship between improvements in lip asymmetry at rest and while smiling after orthognathic surgery in patients with skeletal class III malocclusion. Methods: This study included 21 patients with skeletal class III malocclusion and facial asymmetry. We used preoperative and postoperative CT data and photographs to measure the vertical distance of the lips when smiling. The photographs were calibrated based on these distances and the CT image. We compared preoperative and postoperative results with the t test and correlations between measurements at rest and when smiling by regression analyses. Results: There were significant correlations between the postoperative changes in canting of the mouth corners at rest, canting of the canines, canting of the first molars, the slope of the line connecting the canines, and the slope of the line connecting first molars. The magnitude of the postoperative lip line improvement while smiling was not significantly correlated with changes in the canting and slopes of the canines, molars, and lip lines at rest. Conclusions: It remains difficult to predict lip line changes while smiling compared with at rest after orthognathic surgery in patients with mandibular prognathism, accompanied by facial asymmetry.