Journal of Korean Academy of Oral and Maxillofacial Radiology
/
v.14
no.1
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pp.141-152
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1984
The author analysed the bone changes, the positional relationships between condylar head and articular fossa, and the interrelationship between the bone changes and the abnormal position of condylar head, from 1,036 radiographs of 259 patients with temporomandibular joint arthrosis, which were obtained by the oblique-lateral transcranial projection and orthopantomograms. The results were as follows: 1. Among the radiographic bone changes of the temporomandibular joint arthrosis, deformity was 36.90%(217 case), sclerosis 34.18% (20 cases), errosive chang 25.85% (152 cases) and marginal proliferation 3.06% (18 cases) respectively. 2. In the positional changes between condylar head and articular fossa, the downward positioning of condylar head in centric occlusion was most frequent(36.90%), of which frequency was signifiantly higher than forward positioning (11.22%) and backward positioning(4.76%) in same condition. Also, radiographs showed that the enlargement of articular space showed higher frequency than its narrowing. In the opening position of mouth, the restricted movement of condylar head within articular fossa was most frequent(35.03%). The forward positioning and the downward positioning was 15.65% and 9.52% respectively. Also, radiographs revealed that the incomplete movement or no positional change of condylar head was most frequent. 3. In the interrelationship between bone changes and abnormal position of condylar head, deformity was 42.79% in the cases of downward positioning of condylar head in centric occlusion and 37.50% in those of normal positioning of condylar head in same condition. This revealed that deformity was most frequent bone change in above condylar positionings. However, erossive change was 34.62% in the cases of downward positioning of condylar head in centric occlusion and 33.33% in those of forward positioning. In opening position of condylar head, and deformity in the cases of normal positioning, forward positioning and downward positioning of condylar head was 38.38%, 36.96% and 44.64% respectively. 4. Bone changes of condylar head was 47.11%, articular eminence 41.50% and articular fossa 11.39% respectively. This revealed that the frequencies of bone changes. were higher in the projected portion of bony structures of temporomandibular joint than their depressed portions. On the otherhand, in the bone changes of condylar head, deformity was 59.57% which was the most frequent. In the bone changes of articular eminence and articular fossa, however, sclersis was 41.39% and 65.67% respectively, which was the most frequent in those portions.
We report a case involving a young female patient with severe mandibular retrognathism accompanied by mandibular condylar deformity that was effectively treated with Le Fort I osteotomy and two genioplasty procedures. At 9 years and 9 months of age, she was diagnosed with Angle Class III malocclusion, a skeletal Class II jaw relationship, an anterior crossbite, congenital absence of some teeth, and a left-sided cleft lip and palate. Although the anterior crossbite and narrow maxillary arch were corrected by interceptive orthodontic treatment, severe mandibular hypogrowth resulted in unexpectedly severe mandibular retrognathism after growth completion. Moreover, bilateral condylar deformities were observed, and we suspected progressive condylar resorption (PCR). There was a high risk of further condylar resorption with mandibular advancement surgery; therefore, Le Fort I osteotomy with two genioplasty procedures was performed to achieve counterclockwise rotation of the mandible and avoid ingravescence of the condylar deformities. The total duration of active treatment was 42 months. The maxilla was impacted by 7.0 mm and 5.0 mm in the incisor and molar regions, respectively, while the pogonion was advanced by 18.0 mm. This significantly resolved both skeletal disharmony and malocclusion. Furthermore, the hyoid bone was advanced, the pharyngeal airway space was increased, and the morphology of the mandibular condyle was maintained. At the 30-month follow-up examination, the patient exhibited a satisfactory facial profile. The findings from our case suggest that severe mandibular retrognathism with condylar deformities can be effectively treated without surgical mandibular advancement, thus decreasing the risk of PCR.
Objective: This study aimed to evaluate the following null hypothesis: there are no differences in the morphology of the temporomandibular joint (TMJ) structures in relation to vertical and sagittal cephalometric patterns. Methods: This retrospective study was performed with 131 participants showing no TMJ symptoms. The participants were divided into Class I, II, and III groups on the basis of their sagittal cephalometric relationships and into hyperdivergent, normodivergent, and hypodivergent groups on the basis of their vertical cephalometric relationships. The following measurements were performed using cone-beam computed tomography images and compared among the groups: condylar volume, condylar size (width, length, and height), fossa size (length and height), and condyle-to-fossa joint spaces at the anterior, superior, and posterior condylar poles. Results: The null hypothesis was rejected. The Class III group showed larger values for condylar width, condylar height, and fossa height than the Class II group (p < 0.05). Condylar volume and superior joint space in the hyperdivergent group were significantly smaller than those in the other two vertical groups (p < 0.001), whereas fossa length and height were significantly larger in the hyperdivergent group than in the other groups (p < 0.01). The hypodivergent group showed a greater condylar width than the hyperdivergent group (p < 0.01). The sagittal and vertical cephalometric patterns showed statistically significant interactions for fossa length and height. Conclusions: TMJ morphology differed across diverse skeletal cephalometric patterns. The fossa length and height were affected by the interactions of the vertical and sagittal skeletal patterns.
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.
Journal of Korean Academy of Oral and Maxillofacial Radiology
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v.14
no.1
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pp.121-134
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1984
The authors analyzed the morphological change of bone structure from 3,140 radiographs (1570 joints) of 785 patients with temporomandibular joint arthrosis, which were obtained by the oblique lateral transcranial projection and orthopantomographs. The interrelation of bone change and clinical symptoms, duration of the diseases were examined. Also, the bone changes of articular eminence, condyle, articular fossa were examined according to positional change of the condyle in the mouth open and close state. The results were as follows. 1. In the 785 patients with TMJ arthrosis, 782 patients (99.62%) show the positional change of the condyle. Among them 691 patients (88.03%) show the bone change. 2. In TMJ arthrosis patients with bone changes 451 patients (65.27%) showed both the condylar positional changes and bone changes bilaterally. 198 patients (28.65%) show the condylar positional changes bilaterally and bone changes unilaterally. 3. The bone changes in the TMJ arthrosis were in order of frequency eburnation (647 cases, 32.8%), erosion (548 cases, 27.79%), flattening (418 cases, 21.20%), deformity (138 cases, 6.99%). sclerosis (115 cases, 5.83%), marginal proliferation (106 cases, 5.38%). The region of bone change in TMJ arthrosis with condylar positional changes were in order of frequency the articular eminence (43.97%) condylar head (38.64%), articular fossa (17.39%). In the patients with bone changes, their clinical symptoms were pain (44.34%), clicking sound (33.5%), limitation of mouth opening (22.52%). In the patients complaining pain the most frequent bone change was erosion (28.60%), in the patients complaining clicking sound, eburnation (28.97%) in the patients complaining the limitation, eburnation (29.40%). Also in the patients with the duration below 1 year most common bone change was eburnation. 5. The most common condylar positional change was downward position (39.94%) in closed state, restricted movement of condyle (30.07%) in open state. The condylar positional changes and bone changes according to the region were as follows: a) In the condylar head the most frequent bone change was erosion (30.45%) and the most frequent condylar positional change was downward position (37.40%) in closed state, restricted movement of condyle (33.2%) in open state. b) In the articular eminence the most frequent bone change was eburnation (39.91%) and the most frequent condylar positional change was downward position (39.79%) in closed state, restricted movement of condyle (27.22%) in open state. c) In the articular fossa the most frequent bone change was eburnation (53.94%) and the most frequent condylar positional change was downward position (42.57%) in closed state, restricted movement of condyle (30.32%) in open state.
Journal of the Korean Association of Oral and Maxillofacial Surgeons
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v.36
no.1
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pp.28-38
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2010
The factors influencing the relapse and recurrence of skeletal deformity after the orthognathic surgery include various factors such as condylar deviation, the amount of mandibular set-back, stretching force by the soft tissues and muscles around the facial skeleton. The purpose of this report is to recognize and analyze the possible factors of reoperation after orthognathic surgery, due to early relapses. Six patients underwent reoperation after the orthognathic surgeries out of 110 patients from 2006 to 2009 were included in this study. In most cases, clincal signs of the insufficient occlusal stability, anterior open bite, and unilateral shifting of the mandible were founded within 2 weeks postoperatively. Although elastic traction was initiated in every case, inadequate correction made reoperation for these cases inevitable. The chief complaints of five cases were the protruded mandible combined with some degree of asymmetric face and in the other one case, it was asymmetric face only. Various factors were considered as a major cause of post-operative instability such as condylar sagging, counter-clockwise rotation of the mandibular segment, soft tissue tension related with asymmetrical mandibular set-back, preoperatively existing temporomandibular disorder (TMD), poor fabrication of the final wafer, and dual bite tendency of the patients.
Journal of Korean Academy of Oral and Maxillofacial Radiology
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v.10
no.1
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pp.47-55
/
1980
The author analysed the routine radiographic changes and clinical symptoms of 205 cases of temporomandibular joint arthrosis. The clinical symptoms of the patients were classified and the morphological ylar head, articular eminence, and articular fossa were analized and discussed view point. The positional changes of condylar head and articular fossa relatation in TMJ arthrosis were observed. The frequencies of coincidence between the site of complaints and the site of the abnormal images which could be detected were examined. The results were obtained as follows; 1. Bone erosion, deformity, marginal proliferation and sclerosis were selected from many abnormal images as the radiographic diagnostic criteria of TMJ arthrotic lesions. 2. Abnormal radiographic findings were revealed in 150 cases (73.9%) of 205 total TMJ arthrosis cases and site with abnormal findings coincided with the site of complaints in 106 cases (70.7%) of 150 cases and coincidence rates were higher above fourth decades than below third decades. 3. Sclerosis of the abnormal radiographic findings could be found more often below third decades than above fourth decades. 4. The positional changes of condylar head were revealed in 176 cases (85.9%) of 205 total cases. 5. Pain complaints were revealed in 170 cases(82.9%) and clicking sounds were revealed in 120 cases (58.6%) of clinical symptoms of TMJ arthrosis. 6. No tendency was found so far the differential diagnosis between pain dysfunction syndrom and osteoarthrosis of TMJ.
During the condylar shaving procedure, the articular soft tissue cover can be removed. Author compaired the histological healing process of the articular soft tissue cover between the preservative and unpreservative group group with 45 New Zealand rabbits(Average wt. : about 2.5kg). In unpreservative group, the usual high condylar shave with the removal of soft tissue cover was performed. In the preservative group, the underlying bone, replaced in its original position and sutured. The animals were sacrified 1, 2, 3, 4, 6 weeks interval after operation. The specimens were fixed in 10% neutral formalin and decalcified, paraffin embedded and stained by Hematoxylin & Eosin, and Masson's trichrome. The obtained results were as follows. 1. The condyles of the both group were covered with an articular sop tissue layer. 2. The cartilage cells in subarticular layer has regular continuous patterns in the preservative group but frequently interrupted in the unpreservative group. 3. The incision made in the posterior part of the articular surface for the elevation of the articular soft tissue frequently caused a deformity such as the interruption of the subarticular layer of cartilage. 4. By the above findings, the preservation of articular sop tissue cover may be the effective operation method on concept of bone remodelling.
Background: Along with the advances in technology of three-dimensional (3D) printer, it became a possible to make more precise patient-specific 3D model in the various fields including oral and maxillofacial surgery. When creating 3D models of the mandible and maxilla, it is easier to make a single unit with a fused temporomandibular joint, though this results in poor operability of the model. However, while models created with a separate mandible and maxilla have operability, it can be difficult to fully restore the position of the condylar after simulation. The purpose of this study is to introduce and asses the novel condylar repositioning method in 3D model preoperational simulation. Methods: Our novel condylar repositioning method is simple to apply two irregularities in 3D models. Three oral surgeons measured and evaluated one linear distance and two angles in 3D models. Results: This study included two patients who underwent sagittal split ramus osteotomy (SSRO) and two benign tumor patients who underwent segmental mandibulectomy and immediate reconstruction. For each SSRO case, the mandibular condyles were designed to be convex and the glenoid cavities were designed to be concave. For the benign tumor cases, the margins on the resection side, including the joint portions, were designed to be convex, and the resection margin was designed to be concave. The distance from the mandibular ramus to the tip of the maxillary canine, the angle created by joining the inferior edge of the orbit to the tip of the maxillary canine and the ramus, the angle created by the lines from the base of the mentum to the endpoint of the condyle, and the angle between the most lateral point of the condyle and the most medial point of the condyle were measured before and after simulations. Near-complete matches were observed for all items measured before and after model simulations of surgery in all jaw deformity and reconstruction cases. Conclusions: We demonstrated that 3D models manufactured using our method can be applied to simulations and fully restore the position of the condyle without the need for special devices.
Fractures of the mandibular condyle are among the most frequently occuring facial bone fractures. Anatomical structures around the joint inhibit the ideal reposition of the fragments, so variable treatment modalities have been tried selectivly. There can be functional disturbances postoperatively, and normalization of joint function must be considered primarily in treatment planning. Secondly, the possible joint ankylosis and facial deformity following developmental disturbance of facial skeleton must be considered. The authors reviewed 73 patients treated in Dept. of Oral and Maxillofacial Surgery. Inje College of medicine Pusan Paik Hospital from 1981 to 1987. Also literatures were reviewed, and we obtained some reference points concerning the selection of the treatment modality and prevention of the possible complication.
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