• The korean journal of orthodontics
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• v.21 no.2 s.34
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• pp.325-340
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• 1991

There are evidences that occlusal splint therapy is critical to diagnose hidden akeleto-occlusal disharmonies in malocclusion patients and capable of enhancing stability after orthodontic treatment. In addition, evidences have implicated occlusal splint therapy in condylar positional changes during TMJ disorder treatment. In view of these evidences, this study was performed to investigate the effect of occlusal splint therapy on condylar positional changes in malocclusion patients and the possible clinical application of the occlusal splint as an additional orthodontic tool. For this study, 8 Angle's Class I malocclusion patients, who had centric occlusion-centric relation discrepancy within 1.0 mm and had no clinical symptoms of TMJ disorder, were selected as control group. And 22 malocclusion patients who had centric occlusion-centric relation discrepancy over 1.0 mm were selected and subdivided as Class I Malocclusion group, Class II div. 1 malocclusion group, Class II div. 2 malocclusion group, Open bite group, and Mandibular asymmetry group. For each subject the occlusal splint with mutually protected type of occlusal scheme was applied for 3 months. Condylar positions in centric relation and centric occlusion were measured using Panadent articulators and Panadent condylar position indicator (CPI) before and after occlusal splint therapy. On the basis of this study, the following conclusions might be drawn: 1, In control group, Class II div. 2 malocclusion group, and mandibular assymetry group, there were no significant differences in condylar positions before and after occlusal splint therapy. 2. In Class I malocclusion group, condyles were moved $0.27{\pm}0.45mm$ forward (p < 0.05) and $0.98{\pm}0.25mm$ upward (p < 0.01) after occlusal splint therapy. 3. In Class I malocclusion group, condyles were moved $0.24{\pm}0.21mm$ backward (p < 0.05) and $1.01{\pm}0.33mm$ upward (p < 0.01) after occlusal splint therapy. 4. In open bite group, condyles were moved $1.24{\pm}0.30mm$ upward (p < 0.01) after occlusal splint therapy. 5. In both control and experimental groups, there were no significant differences in lateral condylar positions before and after occlusal splint therapy.

• The korean journal of orthodontics
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• v.10 no.1
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• pp.71-79
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• 1980

The purpose of this study was (1) to determine the prevalence of some causes by which dental occlusion might be affected , (2) to determine the prevalence of malocclusion, and types of molar, vertical incisor and horizontal incisor relationships, and (3) to examine the sex difference in the prevalence ratios, and (4) to determine the between-examiner differences in assessing types of dental occlusion. The material consisted of 1281 males and 811 females, total 2091 persons, aged 17 to 21 years. Two examiners who were graduate students in the orthodontic course, examined independently dental occlusion of the material. Before calculating the statistics, the subjects consisted of 156 mates and 164 females, total 320 persons, haying any one or more causes suspected to affect dental occlusion, was eliminated. Then the remained subjects, 1124 males and 647 females, total 1771 persons, were assessed. The results were as follows 1. The prevalence of some causes by which dental occlusion might be affected was 15.32 per cent. The missing rate of any one or more first molars was 8.85 percent, that of any one or more teeth positioned anterior to the first molar was 3.83 per cent. The prevalence of crossbite of the first molar was 0.48 per cent, that of retained primary teeth was 0.77 percent, and that of orthodontic treatment was 0.43 per cent. 8. The rate of between-examiner difference was 12.53 per cent in assessing the types of molar relationship, 18.86 percent in assessing the types of horizontal incisor relationship, and 26.37 percent in assessing the types of horizontal incisor relationship. 3. There was no sex difference in the prevalence ratios of the types of molar relationship. The prevalence of Class I molar relationship was 80.91 percent, that of Class II was 5,03, that of Class II subdivision was 4.01, Percent, that of Class III was 5.99 percent and that of Class III subdivision was 4.07 percent. 4. In the prevalence of the types of horizontal incisor relationship, there were no sex differences except that of Class II division 2. The prevalence of Class I horizontal incisor relationship was 73.12 percent, that of Class II division t was 12.03 percent, that of Class II division 2 was 6.58 percent in male and 4.33 percent in female, and that of Class III was 9.09 percent. 5. In the prevalence of the types of vertical incisor relationship, there were no sex differences except that of deep bite, The prevalence of open bite was 2.20 per cent, that of edge-to-edge bite was 9.15 percent, that of normal bite was 76,34 percent, and that of deep bite was 14.15 percent in male and 9.12 percent in female. 6. There was no sex difference in the prevalence of malocclusion the prevalence of malocclusion was 82.67 percent and that of normal occlusion was 17.33 percent. 7. There was a tendency that when Class I molar relationship changed to Class II, incisor relationships were to be larger overjet or upright upper incisors and deep bite, but when that changed to Class III molar relationship, these were to be cross bite and openbite.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.2
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• pp.246-250
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• 2000

The oral screen is a functional appliance, suitable for the treatment of developing malocclusion associated with aberrant muscular patterns. The better muscle balance between tongue and the buccinator mechanism can be established, and the reestablishment of normal growth and development can be achieved. The oral screen can be used for the correction of the following conditions : (1) thumbsucking, tongue thrusting and lip biting, (2) mouth breathing, (3) mild distocclusion with premaxillary protrusion, (4) open bites in deciduous and mixed dentition, and (5) incompetent lips. The patient should wear the oral screen every night and also during the day whenever possible. The effects of oral screen can be elevated through lip seal exercise : the lips should be kept in contact all the time to improve the lip seal. In the presented two cases, the patients were considered mouth breathers and to have incompetent lips, and one patient with maxillary incisal protrusion and the other with open bite. They were instructed to wear the oral screen with lip seal exercise. After wearing the appliance for 1 and 2 years respectively, mouth breathing was decreased and lip length and strength were increased, the maxillary incisors were retruded and open bite reduced.

• The korean journal of orthodontics
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• v.47 no.1
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• pp.39-49
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• 2017

Objective: This retrospective, cross-sectional study aimed to establish reference data for normal crown and root lengths and the root-crown ratios (R/C ratios) for the mature maxillary and mandibular incisors in a Korean population by using cone-beam computed tomography (CBCT). Methods: We included 672 Korean patients (141 men and 531 women; mean age, $27.2{\pm}7.7years$) who underwent CBCT examinations during various dental treatments. Crown and root lengths and the R/C ratios of the maxillary and mandibular incisors were measured using CBCT data, which were analyzed to detect significant differences between demographic factors as well as sagittal and vertical skeletal or occlusal relationships. Results: Teeth of the same type in each half-arch were symmetrical. The mean R/C ratios varied from 1.1 to 1.2 for the maxillary incisors and from 1.3 to 1.4 for the mandibular incisors. Crown and root lengths were greater in men than in women, regardless of tooth type. Root lengths and R/C ratios for the mandibular incisors were significantly greater in patients with skeletal Class II malocclusion or an excessive overjet than in the other patients. The R/C ratios for the mandibular incisors were lower in patients with an open bite than in those with a normal or deep bite. Moreover, the R/C ratios for the mandibular incisors increased with age. Conclusions: The data obtained in our study can serve as reference values for crown and root lengths and the R/C ratios for the maxillary and mandibular incisors in the Korean population.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.35 no.3
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• pp.189-194
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• 2013

Osteochondroma is a benign neoplasm, osseous projection surrounded with cartilage, 35.8% of benign osseous tumor, 8.5% of whole osseous tumor and usually arises from the skeletal bone. Osteochondroma is a cartilaginous derivation and relatively uncommon in the craniofacial bone. Osteochondroma of the mandible has slow growth rates which mainly affect women around forty years of age and it can appear through the coronoid process and mandibular condyle, especially in the medial half. Clinical finding associated with osteochondroma of condyle are primarily a palpable, painless temporomandibular area mass with facial asymmetry, malocclusion and midline deviations. Sometimes pain and dysfunction like trismus often accompany the anatomic derangement. Other features include malocclusion with open-bite on the affected side and cross-bite on the contralateral side. In this study, a 45-years old female patient exhibits pain on the left temporo-mandibular joint area and malocclusion due to loss of the molar region with osteochondroma on the top left of her mandibular condyle head. The patient is able to recover gradually from the symptom through treatments on manipulation, stabilization splint, arthroscopic lavage and surgical excision, thus, this is reported as a clinical case.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.12 no.2
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• pp.158-160
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• 2001

Ankyloglossia is the presence of a lingual frenulum, which can range from a mucous membrane band to a short and thick band and, in extreme cases, to fusion of the tongue to the floor of the mouth. The effects of such a condition, in addition to speech defects and occasionally restriction of sucking, including dental deformities, such as open bite, or even prognathism. Treatment is surgical. The preferred treatment is horizontal sectioning of the frenulum down to the lingual septum and then suturing of the mucosa. The main problem after the healing of surgical wound is adhesion and contracture. Adhesion restrict the movement of tongue like tongue-tie. Z-plasty at the site of incision can solve this problem by changing the direction of scar. We have experienced a patient with ankyloglossia with speech defect, who underwent frenuloomy by Z-plasty. So we present a surgical treatment of Ankyloglossia using Z-plasty and discuss the treatment with a review of literature.

• Journal of the korean academy of Pediatric Dentistry
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• v.21 no.2
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• pp.504-509
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• 1994

Achondroplasia is characterized by undergrowth of long bones and cartilages and by low height. The name of this disease had been called classical chondrodystrophy, dyschondroplasia, chondrodystrophy and micromelia before Parrot reported the term of this disease as Achondroplasia. We are reporting in this paper on an 3-year and 4-month-old boy with achondroplasia. The dental findings are as follows: 1. Open bite and relatively mandibular prognathism were observed in the front teeth. 2. The size, number, shape, structure of the teeth were usual and the tongue was a little bigger than the normal. 3. The metacarpal bones were short and broadening. Mesial, distal border of the prox. phalanges were irregular and also trabecular pattern was abnormal in the hand-wrist P-A view. 4. According to lat. cephalometric analysis, the cranial basis was underdeveloped.

• The korean journal of orthodontics
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• v.42 no.5
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• pp.270-278
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• 2012

In the correction of dental Class III molar relationship in skeletal Class II patients, uprighting of the mandibular posterior segments without opening the mandible is an important treatment objective. In the case reported herein, a C-tube miniplate fixed to the lower labial symphysis and connected with a nickel-titanium reverse-curved archwire provided effective uprighting of the lower molars, without the need of orthodontic appliances on the mandibular anteriors. Using this approach, an appropriate magnitude of force is exerted on the molars while avoiding any negative effect on the mandibular anteriors.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.5
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• pp.349-356
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• 2012

Osteochondroma is one of the most common benign tumors that occur in the bone, but in the head and neck region, osteochondroma appears rarely. Malocclusion, temporomandiublar disorders and facial asymmetry can occur in most cases with osteochondroma of the mandibular condyle. Most surgeons prefer massive removal of osteochondroma and reconstruction of condyle, simultaneously, to prevent various complications, such as a lateral open bite on the contralateral side. We report a surgical treatment and reconstruction of osteochondroma on a mandibular condyle through intraoral approach.

• The Journal of the Korean dental association
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• v.58 no.4
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• pp.206-212
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• 2020

The infraocclusion is defined as a condition, in which teeth are present with their occlusal surface below the neighboring teeth, and long after, they reach occlusion. The most common cause of infra-occlusion is thought to be ankylosis. The treatment options for patient with infraocclusion of primary molars are observation, restoration and surgical removal of the affected teeth. We report a case of 8 - year - old boy who visited our clinic for consultation of orthodontic treatment. The patient was diagnosed by multiple infraoccluded primary molars with permanent successors. Surgical extraction were performed on primary molars. After follow-up of 7 months period, #44, 45 were erupted and the degree of posterior open bite was decreased.