• Maxillofacial Plastic and Reconstructive Surgery
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• v.16 no.2
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• pp.157-161
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• 1994

A 14-year-old male patient was referred to us for evaluation of Right TMJ clicking sound and mandibular deviation during mouth opening. On examinaaation, protrusion and lateral excursion was also restricted. Radiographs showed hook-like curved elongation of Right coronoid process with limitation o right condylar translation. His past medical and dental history was noncontributory. This patient underwent an extraoral coronoidectomy and the specimen revealed coronoid process malformation mimicking condylar head. Microcoically, the specimen discloses mature bony trabeculae. At postoperative 5 days, physical therapy was instituted. At present, this patient could open his mouth well with any clicking sound and mandibular deviation. The asymmetric face of this patient is expectated to be corrected by periodic observation and remained growth porential. If not to be corrected, orthognathic surgery will be done.

• Journal of Oral Medicine and Pain
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• v.48 no.3
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• pp.123-130
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• 2023

This case report describes the orthodontic treatment of a patient with severe anterior open bite and skeletal class II malocclusion with temporomandibular joint (TMJ) osteoarthritis (OA) of the left condyle. The 21-year-old male patient had open-bite malocclusion, mild crowding, and protrusion of the anterior teeth. Mild erosive changes were detected in the anterior part of the left mandibular condyle on cone-beam computed tomography; however, because no clinical symptoms were present, orthodontic treatment was performed. It is imperative to consider the potential implications of orthodontic treatment on the stability of the TMJ throughout the duration of treatment, as any instability can exacerbate TMJ OA. Hence, it is crucial to opt for the least invasive treatment modality available. In this regard, orthodontic treatment using a skeletal anchorage system as an alternative to conventional orthognathic surgery for patients with open bite holds great promise, as it not only ensures mandibular stability but also significantly ameliorates the open-bite condition.

• The korean journal of orthodontics
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• v.39 no.4
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• pp.257-272
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• 2009

This case report describes the treatment of an adult patient with a Class I canine and molar relationship but a convex profile with a retrognathic mandible and marked lip protrusion, as well as an excessive lower anterior facial height and reduced transverse width on both arches due to a nasal airway obstruction. The constricted arches were expanded by surgically-assisted rapid palatal expansion and the application of a Schwarz appliance to the maxilla and mandible. Acceptable facial balance was obtained using contemporary directional force technology with microimplant anchorage (MIA), which provided horizontal and vertical anchorage in the maxillary and mandibular posterior teeth, as well as intrusion and torque control in the maxillary anterior teeth, resulting in a favorable counterclockwise mandibular response. The total treatment period was 29 months and the results were acceptable for 13 months after debonding.

• Journal of Oral Medicine and Pain
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• v.16 no.1
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• pp.85-93
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• 1991

In this study, 88 dental students were examined to evaluate the relationship between occlusal states and TM disorders for the epidemiologic study of TM disorders. The clinical evaluation were composed of mandibular movement, TMJ noise, occlusal states and muscle palpation. The following results were disclosed. 1. The frequencies of pain on mandibular movement were 3.4% on maximum opening, 1.13% on protrusion and no pain on laterotrusion. 2. The frequencies on TMJ sound were 21.6% in click, 1.13% in crepitus. 3. The frequency of tenderness on palpation was 12.5% on extra oral, intraoral and neck muscles, tenderness on palpation of TMJ capsule were reported 5 cases, and 4 of them were female. 4. The distribution of Angle's classification was found 79.5% in class I, 4.5% in clasII-div.1 and 15.9% in class III. There was no significant differences on TM disorders between Angles classifications. 5. There was no significant differences on TM disorders between the subjects of canine guided occlusion and group function occlusion, and also for the differences between the subjects of nonworking side interferences and no interferences on laterotrusion. 6. There was no significant differences on TM disorders between the subjects of anterior teeth trauma in C.C. and no anterior teeth trauma, but there were significant differences between the subjects of posterior protrusive contact and no posterior protrusive contact.

• The korean journal of orthodontics
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• v.14 no.1
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• pp.75-92
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• 1984

This study attempted to analyze the distribution of stress, to examine the bending effect in the mandible according to the pulling directions and determine on which pulling directions are adequate when an orthopedic force was applied to the mandible. An orthopedic force, 500gm, was applied to the gnathion, one point of the chin area, in three directions. The three directions were ; high puli' from gnathion to the center of condyle head, and vertical pull, from gnathion to a parallel line with the posterior border of the ramus, and medium pull, from the gnathion to a parallel line with the lower border of mandible. The distribution of principal stress, bending moment and amount of displacement within the mandible was analyzed by a 3-dimensional finite element method and that of the various portions of mandible were computed and compared according to the pulling directions. The results were as follows : 1. The bending moment of each part of a mandible has been found to be markedly larger in case of vertical pull than in case of either high pull or medium pull. In vertical pull the bending moment turned out to largest at the condyle head and neck portion, the gonial angle portion, the coronoid portion and the ascending ramus portion, respectively, while comparatively large at the cuspid and bicuspid portion and the first molar portion. In case of high pull it was largest at the gonial angle portion and becoming smaller at the coronoid portion, the ascending ramus portion, the condyle head and neck portion, and the cuspid and bicuspid portion, in that order. In case of medium pull, however, the bending moment was largest at the condyle head and neck portion, becoming smaller at the first molar portion, the ascending ramus portion, the coronoid portion, the cuspid and bicuspid portion, and gonial angle portion, in that order. 2. As for the bending effect it was calculated to be mostly oriented downward at the mandibular body and backward at the mandibular ramus in both high pull and vertical pull. In case of medium pull it was oriented upward at the mandibular body and forward at the mandibular ramus. 3. The bending effect also turned out to be mostly oriented outward in case of high pull and medium pull, and inward in vertical pull. 4. At the mandibular body and ramus, the bending effect in the upward-downward direction and that in the forward-backward direction were found to be larger than in the inward-outward direction. 5. If and when we expect any correcting effect on the mandibular protrusion by means of the chin cup appliance, we can say sure as conclusion that high pull and vertical pull are more effective than medium pull.

• Journal of Oral Medicine and Pain
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• v.23 no.1
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• pp.65-73
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• 1998

This study evaluated whether substantial airflow resistance changes occurred by changing jaw position in normal and snoring subjects. A case-control design was utilized to assess group differences. Subjects included 11 snoring patients and 10 non-snoring subjects. Airway resistance was assessed using a whole body plethysmograph. Subjects in this study had their mouth opening standardized to a position of 7 mm of vertical separation and the resistance was measured under the following conditions; normal jaw position and 2/3 maximum protrusive jaw position. The results were as follows : 1. The airway resistance was higher in snoring group than in non-snoring group. 2. Both groups had a significant decrease in their airflow resistance upon jaw protrusion. In conclusion, these data document that airflow resistance can be significantly influenced by jaw positioning. Moving the jaw in a protrusive position produced reduction of resistance.

• The korean journal of orthodontics
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• v.23 no.4 s.43
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• pp.475-483
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• 1993

The purpose of this study was to investigate the treatment effects on anterior crossbite patients using chin cap and labiolingual arch appliance. In the present study, I statistically evaluated measurement values on a cephalogram before and after treatment form twenty anterior crossbite cases. The results were as follows: 1. In the craniofacial patterns, cranial base increased after treatment. 2. In the maxillo-mandibular relationship, ANB and Facial convexity significantly increased. 3. In the denture patterns, occlusal plane, Ul to FH and Overjet significantly increased. On the contrary overbite decreased significantly. Lower incisors inclined lingually. 4. In the soft tissue profile changes, lower lip protrusion was signifacantly improved.

• Journal of Oral Medicine and Pain
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• v.6 no.1
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• pp.9-14
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• 1981

Maximal active movements of the mandible in the vertical and the horizontal plane were measured in 106 mem and 78 women. ranging from 20 to 29 years old, with a method devised by agerberg. The studied persons who were dental students of the School of Dentistry Seoul National University (SNU), nurses and dental auxiliaries of the SNU Hospital, had no pain or severe symptoms of dysfunction of the masticatory system. The obtained results were as follows : 1. The mean values for maximal opening and protrusion differed significantly between men and women, 55.9 mm and 49.7 mm, 9.3 mm and 7.4 mm respectively. 2. The means found for maximal lateral movement to the right and to the left were practically the same, 8.5 - 9 mm and did not differ with sex. 3. The lower limit of the normal range of horizontal movements may be regarded as 4 mm for men and 3 mm for women and maximal opening as 44 mm for men and 39 mm for women. 4. The maximal mandibular movement ranges of 20-year old person with 95 % probability were calculated and presented grphically.

• The Journal of the Korean dental association
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• v.57 no.2
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• pp.93-99
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• 2019

Ectodermal dysplasia is a genetic disorder in which various clinical manifestations involve two or more of the differentiated tissues of the ectoderm. Facial deformity, which is frequently associated with ectodermal dysplasia, appears in the form of cleft lip or cleft palate, especially in the middle facial area.Cleft and tooth defects result in decreased alveolar bone development.This leads to severe skeletal incongruity. Facial features include frontal protrusion, malar bone hypoplasia, flat nose, mandibular prominence and long lower facial height. This clinical report presents treatment including orthognathic surgery of a patient with Hypohidrotic Ectodermal dysplasia with cleft palate.

• The korean journal of orthodontics
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• v.44 no.5
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• pp.236-245
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• 2014

Objective: To evaluate the therapeutic effects of a preformed assembly of nickel-titanium (NiTi) and stainless steel (SS) archwires (preformed C-wire) combined with temporary skeletal anchorage devices (TSADs) as the sole source of anchorage and to compare these effects with those of a SS version of C-wire (conventional C-wire) for en-masse retraction. Methods: Thirty-one adult female patients with skeletal Class I or II dentoalveolar protrusion, mild-to-moderate anterior crowding (3.0-6.0 mm), and stable Class I posterior occlusion were divided into conventional (n = 15) and preformed (n = 16) C-wire groups. All subjects underwent first premolar extractions and en-masse retraction with preadjusted edgewise anterior brackets, the assigned C-wire, and maxillary C-tubes or C-implants; bonded mesh-tube appliances were used in the mandibular dentition. Differences in pretreatment and post-retraction measurements of skeletal, dental, and soft-tissue cephalometric variables were statistically analyzed. Results: Both groups showed full retraction of the maxillary anterior teeth by controlled tipping and space closure without altered posterior occlusion. However, the preformed C-wire group had a shorter retraction period (by 3.2 months). Furthermore, the maxillary molars in this group showed no significant mesialization, mesial tipping, or extrusion; some mesialization and mesial tipping occurred in the conventional C-wire group. Conclusions: Preformed C-wires combined with maxillary TSADs enable simultaneous leveling and space closure from the beginning of the treatment without maxillary posterior bonding. This allows for faster treatment of dentoalveolar protrusion without unwanted side effects, when compared with conventional C-wire, evidencing its clinical expediency.