• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.12 no.1
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• pp.49-56
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• 1982

The purpose of this study was to observe the anatomic variation of condylar head and the positional relationship between condylar head and other anatomic structures of head by means of cephalometry using the submentovertex cephalogram from each person in centric occlusion for producing a good quality of temporomandibular joint radiograph. The 100 submentovertex cephalograms of 100 Korean adults consisted of 50 females ranged from 20 to 24 years age and 50 males ranged from 22 to 30 years age, were studied and analyzed statistically. The results were as follows; 1. The mean of the horizontal angulation of condylar head to the transmeatal line (EE-LA) was 18.5° (S.D. 7.9°), and all measurements that indicate the horizontal angulation of condylar head showed considerable differences among individuals. 2. In the comparison of male vs. female in the measurements, statistically significant differences were found in the majority of measurement items, and with exception of R-LA and LA-LA, the rest of these measurements were larger in male than in female. 3. In the comparison of left vs. right in the measurements, statistically significant differences were found in the majority of measurement items, and with exception of PC-CC, the rest of these measurements were larger in right than in left. As above, because the majority of measurements that involve the horizontal angulation of condylar head varied among individuals, between male and female, and between left and right, the condition of various temporomandibular joint radiography should be determined by means of cephalometry using the submentovertex cephalogram for producing the accurate radiographic image of temporomandibular joint.

• 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.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.25 no.2
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• pp.447-457
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• 1995

The subjects of this study consisted of 75 patients with 83 condylar fractures, who were admitted to Chonbuk National University Hospital from Jan. 1988 to Oct. 1995. The purpose of this study was to compare the imagings of conventional radiograms with those of computed tomograms and to aid in the diagnosis of condylar fractures. Also the author evaluated the usefulness of 3-dimensional reconstructive imaging in condylar fractures. The obtained results were as follows: 1. The condylar fractures were observed mainly between 2nd and 4th decades, but there was no significant difference of incidence between decades. The incidence of condyalr fractures by fracture site was subcondyalr(44.6％), condylar head(36.1％), condylar neck(19.3％) in orders. 12 of 30 condylar head fractures were sagittal splitting fractures. 2. According to the relationship of condylar head to articular fossa, the incidence of condylar fractures was higher in Type II and Type m. And the incidence of subcondylar fractures was higher in Type I classified by Mclennan. But there was no significant difference of incidence between Types. 3. The more the fracture fragments were displaced, the easier the fracture patterns were detected in conventional radiograms. The computed tomograms were also useful in the diagnosis of sagittal splitting fractures which were displaced mesially. 4. The 3-dimensional reconstructive imaging were useful in the evaluation of the fracture patterns, but they were not useful when the size of fragment and the degree of displacement were small.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.13 no.1
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• pp.7-15
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• 1983

The purpose of this study was to investigate the radiographic images of the condylar head in clinically normal subjects and the TMJ patients using standardized projection technique. 45 subjects who have not clinical evidence of TMJ problems and 96 patients who have the clinical evidence of TMJ problems were evaluated, but the patients who had fracture, trauma and tumor on TMJ area were discluded in this study. For the evaluation of radiographic images, the author has observed the condylar head positions in closed mouth and 2.54㎝ open mouth position taken by the standardized transcranial oblique lateral projection technique. The results were as follows: 1. In closed mouth position, the crest of condylar head took relatively posterior position to the deepest point of the glenoid fossa in 8.9 % of the normals and in 26.6% of TMJ patients. 2. In 2.54㎝ open mouth position, condylar head took relatively posterior position to the articular eminence in 2.2% of TMJ patients and 39.6% of the normals. 3. In open mouth position, the horizontal distance from the deepest point of the glenoid fossa to the condyla head was 13.96㎜ in the normals and 10.68㎜ in TMJ patients. 4. The distance of true movement of condyalr head was 13.49㎜ in the normals and l0.27㎜ in TMJ patients. 5. The deviation of mandible in TMJ patients was slightly greater than that of the normals.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.40
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• pp.13.1-13.8
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• 2018

Background: We evaluated change in the mandibular condyle after orthognathic surgery using cone-beam computed tomography (CBCT) in patients with facial asymmetry. Methods: Thirty patients with skeletal class III malocclusion and mandibular prognathism or facial asymmetry were classified into two groups according to the amount of menton deviation (MD) from the facial midline on anteroposterior (AP) cephalogram: group A (asymmetry, MD ≥ 4 mm; n = 15) and group B (symmetry, MD < 4 mm; n = 15). Position and angle of condylar heads on the axial, sagittal, and coronal views were measured within 1 month preoperatively (T0) and postoperatively (T1) and 6 months (T2) postoperatively. Results: On axial view, both groups showed inward rotation of condylar heads at T1, but at T2, the change was gradually removed and the condylar head returned to its original position. At T1, both groups showed no AP condylar head changes on sagittal view, although downward movement of the condylar heads occurred. Then, at T2, the condylar heads tended to return to their original position. The change in distance between the two condylar heads showed that they had moved outward in both groups, causing an increase in the width between the two heads postoperatively. Analysis of all three-dimensional changes of the condylar head positions demonstrated statistically significant changes in the three different CBCT views in group B and no statistically significant changes in group A. Conclusions: There was no significant difference between the two groups in condylar head position. Because sagittal split ramus osteotomy can be performed without significant change in symmetrical and asymmetrical cases, it can be regarded as an effective method to stabilize the condylar head position in patients with skeletal class III malocclusion and mandibular prognathism or facial asymmetry.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.21 no.1
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• pp.65-72
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• 1991

For the enhancement of a comprehension in temporomandibular joint radiographs, the author has compared and analysed the roentgenographic images of the temporomandibular joint of human dry skull which was taken by submentovertex projection, panoramic radiography, oblique lateral transcranial projection, corrected anterio-posterior tomogram and corrected lateral tomogram. The obtained results were as follows. 1. The submentovertex projection represented in detail the both poles and the posterior surface of the condylar head of the mandible. 2. The oblique lateral transcranial projection represented the articular space, the outer contour of the condylar head and the position of the condylar head within the mandibular fossa, but the relationship of the temporomandibular joint was not revealed accurate, because of the oblique direction of a central ray in taking radiographs. 3. The corrected antero-posterior tomogram was superior method in representation of roent- genographic images of the superior surface and the both poles of the condylar head and the corrected lateral tomogram was considered as the most accurate method among some radiographic techniques for the interpretation of articular space and condyle-fossa relationship. 4. It was possible to observe three-dimensionally the head of condyle with the combinated use of submentovertex projection, corrected antero-posterior tomogram and corrected lateral tomogram.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.13 no.1
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• pp.151-162
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• 1983

The author analyzed the morphologic changes of bone structure from 848 radiograph is (424 joints) of 212 patients with temporomandibular joint arthrosis, which were obtained by the oblque-Iateral transcranial projection and orthopantomography. The interelation of the bone changes and condylar head positions the results were as follows: 1. In the 212 patients with TMJ arthrosis, 210 patients(99.05%) show the condylar positional changes. Among them, 187 patients 989.05%) show the bone changes. 2. In TMJ arthrosis patients with bone changes, 10% patients(57.75%) show both the condylar positional changes and bone changes. 66 patients( %) show the condylar psoitional changes bilaterally and bone changes unilaterally. On the other hand, 11 patients (5.88%) show the condylar positional changes unilaterally and bone change bilaterally. 3. The bone changes in the TMJ arthrosis patients with the condylar positional changes were as follows: There were the flatlening of articular surface in 103 cases (26.55%) the erosion in 99cases 925.57%), and the erosion in 88 cases (22.68%). There were not much differences among the three types of bone changes. And the deformity in 70 cases (18.04%), the sclerosis in 22 cases(5.67%), the marginal protiferation in 6 cases(1.55%) were seen. 4. The regions of bone changes in TMJ arthrosis patients with condylar positional changes were as follows: They occurred at the condyle head(51.04%), the articular eminence(39.20%) and the articular fossa(9.60%) in that order. The condylar positional changes and bone changes according to the regions were as follows: a) In the bone changes at the condyle head, the flatteming (34.63%) was a most frequent finding and the deformity(27.63%) the erosion(24.32%) in the order. In the condylar positional changes, the downward positioning of condyle(41.44%) was a most frequent finding in the mouth closed state and the restricted movement within the articular fossa(35.46%) in the mouth open state. b) In the bone changes at the articular eminence, the eburnation(33.26%) was a most frequent finding and the flatteming(31.16%), the erosion(28.37%) in that order. In the condylar positional changes, the downward positionirg of condyle(39.81%) was a most frequent finding in the mouth closed state and the restricted movement within the articular fossa(24.77%) in the mouth open state. c) In the bone changes at the articular fossa, the eburnation(72.90%) was amost frequent finding and theerosion(17.76%), the sclerosis(9.35%) in that arder. In the condylar positional changes, the downward positionirg of condyle(41.5%) was a most frequent finding in the mouth closed state and the mormal positionirg of condyle(27.78%) in the mouth open state.

• The Journal of the Korean dental association
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• v.56 no.3
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• pp.134-141
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• 2018

Purpose: To measure the head tilting angle creating initial condylar cut-off and to find the head position inducing the superimposition of the cervical vertebrae over the mandibular ramus on panoramic radiograph. Materials and Methods: The panoramic radiographs were taken with Didactic skull on cervical spine model (Scientific GmbH, Hamburg, Germany) using Kodak 8000c Digital Panoramic radiography. For the inherent radiolucency of the plastic skull model, radiopaque 1 mm diameter lead wires were attached along the margin of the mandibular condyle, ramus, mandibular body, cervical vertebrae, and FH plane of the skull model. For measuring the head tilting angle creating the condylar head cutoff, panoramic radiographs were taken by tilting the FH plane downward in 5 degree increments. For finding the distance between transverse process of the third cervical vertebra and gonion inducing superimposition of cervical vertebrae on the mandibular ramus, panoramic radiographs were taken by decreasing the distance in 0.5 cm increments. Result and Conclusion: The condylar cutoff began to appear when the head of skull model was tilted downward by 15o. As the head tilting angle increasing, the condylar cutoff became more prominent. The superimposition of cervical vertebrae over the mandibular ramus began to appear when the distance between the gonion and third cervical vertebra was 1.0 cm. As the distance decreasing, the superimpostion became more prominent.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.9 no.1
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• pp.13-18
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• 1979

The purpose of this study was to investigate the radiographic images of Temporomandibular joint trouble patients. This study included 186 patients with the chief complaints of TMJ pain and dysfunction. Their age ranged from 17 to 68 years. All patients were identified in the department of Dental mary of College of Dentistry, Seoul National University, Apr. 1978 to Jun. 1979. The author has observed the radiographic variations of two positions of condylar head taken by modified transcranial oblique-lateral projection, which are one in centric occlusion and the other in 1 inch(2.54㎝) mouth open. The results were obtained as follows; 1. In centric occlusion, the distances and positional relationship between the summit of condylar head and the deepest point of articular fossa revealed more or less large variations; Normal range is of 37.9%, anterior displacement of 37.3% and posterior displacement of 22.6%. 2. In the horizontal movement of condylar heads when on 1 inch mouth open, it was revealed that normalrange was of 46.5%, anterior displacement of 12.3%, posterior displacement of 41. 1 %. 3. In the positional interrelationship of both condylar heads when on 1 inch mouth open, it was revealed that symmetry(71. 5%) occurred approximately 2.5 times as many as asymmetry. 4. In both centric occlusion and 1 inch mouth open, it was showed that almost all estimated figures were greater in male than in female, and in the horizontal movement of condylar head when on 1 inch open, it was showed that hypermobility was dominant in male and hypomobility in female.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.4 no.1
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• pp.31-37
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• 1974

The author has studied roentgenographic images of temporomandibular articulation using various conventional roentgenographies. The roentgenographic images have obtained by application of the contrast media on the glenoid fossa and condylar head in a human dry skull. Comparing the various roentgenograms by Modified Transcranial projection, A-P T.M. articulation projection, Reverse Towne projection, Mayer projection and Bregma-Menton projection. The author has drawn following results. 1. The sharp radiogaphic details were obtained by all technics used except the Bregma-Menton projection, which seemed to be impractical to the study of T.M.J. because of to be shortened the image of condylar head. 2. The best image of the condyle-fossa relationship was appeared by Modified Transcranial projection and better image was acquired by Orbito-Ramus projection, but there were all inferior in Reverse Towne projection, Mayer projection and Bregma-Menton projection. 3. In all of the above techniques, the radiographic images of condylar head were clear and were appeared to be the convex type in Modified Transcranial projection, the angled type in Orbito-Ramus and Reverse Towne projection, the flat type in Mayer projection and the distorted angled type in Bregma-Menton projection. 4. The radiographic image of condylar head was shortened in Bregma-Menton projection only and was magnified somewhat in other projection.