• The korean journal of orthodontics
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• v.27 no.4 s.63
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• pp.523-538
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• 1997

In order to investigate TMD prevalence in malocclusion patients and to study its relationship with occlusal factors, 205 malocclusion patients (M67, F138, 6Y1M-46Y8M) were examined. The following examinations were carried out, Questionnaire personal history, TMD symptoms, and the associated factors Clinical examination : TMJ sound and maximum mouth opening Orthopantomogram : condyle abnormalities, length of Co'-Inc' and Co'-Go', ratio Co'- Inc'/ Co'-Go', and depth of antegonial notch Transcranial view limitation of anterior movement of condyle Model Angle classification, overjet, overbite, midline discrepancy, missing of posterior teeth, posterior crossbite, attrition of palatal cusp of maxillary molars, crowding/spacing The results could be summarized as follows, 1. The prevalence of TMD showed that Helkimo Anamestic Inder(Ai) 0 was $46.8\%$, Ai I was $22.0\%$, Ai II was $31.2\%$ and subjective symptoms increased with aging (p<0.001) and were frequent in females (p<0.05). 2. Flattening ($4.4\%$) was the most frequent condyle abnormality on Orthopantomogram, and $8.3\%$ of subjects showed some abnormalities on Orthopantomogram. 3. The cases with neck and shoulder pain (p<0.001), clenching, lip biting (p<0.01), and headache (p<0.05) showed higher scores of Ai. 4. Angle class II showed high frequency of condylar abnormalities on Orthopantomogram, and subjects whose palatal cusp of maxillary molars had been attrided had the tendency to show high hi scores (p<0.05). The other occlusal factors had nothing to do with the symptoms of TMD. 5. In the cases that 1)the value of Co'-Inc', Co'-Go' or Co'-Inc'/Co'-Go' were low or 2)the differences of Co'-Go' or Co'-Inc'/Co'-Go' between the right and the left were large, condylar abnormalities were frequently obserbed on Orthopantomogram.

• 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.29 no.1
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• pp.100-106
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• 2002

The prevalence of Class III malocclusion is approximately 5% in the Caucasian population, rising to as mush as 50% in the Japanese and Korean population. Recent studies have suggested than 63% of this malocclusion display maxillary retrusion. If left untreated, the malocclusion tends to worsen. Consequently, early treatment is commonly indicated to obtain a more normal jaw relationship. This report is 2 cases treated patients who diagnosed as skelectal Class III malocclusion due to deficient maxilla using facemask.

• The korean journal of orthodontics
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• v.46 no.3
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• pp.137-145
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• 2016

Objective: The purpose of this study was to investigate the characteristics of orthodontic patients at Yonsei Dental Hospital from 2008 to 2012. Methods: We evaluated Angle's classification from molar relationships, classification of skeletal malocclusion from the A point-nasion-B point angle, facial asymmetry, and temporomandibular joint disorders (TMDs) from the records of 7,476 patients who received an orthodontic diagnosis. The orthognathic surgery rate, extraction rate, and extraction sites were determined from the records of 4,861 treated patients. Results: The patient number increased until 2010 and gradually decreased thereafter. Most patients were aged 19-39 years, with a gradual increase in patients aged ${\geq}40years$. Angle's Class I, Class II divisions 1 and 2, and Class III malocclusions were observed in 27.7%, 25.6%, 10.6%, and 36.1% patients, respectively, with a gradual decrease in the frequency of Class I malocclusion. The proportion of patients with skeletal Class I, Class II, and Class III malocclusions was 34.3%, 34.3%, and 31.4%, respectively, while the prevalence of facial asymmetry and TMDs was 11.0% and 24.9%, respectively. The orthognathic surgery rate was 18.5%, with 70% surgical patients exhibiting skeletal Class III malocclusion. The overall extraction rate among nonsurgical patients was 35.4%, and the maxillary and mandibular first premolars were the most commonly extracted teeth. Conclusions: The most noticeable changes over time included a decrease in the patient number after 2010, an increase in the average patient age, and a decrease in the frequency of Angle's Class I malocclusion. Our results suggest that periodic characterization is necessary to meet the changing demands of orthodontic patients.

• Journal of the korean academy of Pediatric Dentistry
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• v.2 no.1
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• pp.13-17
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• 1975

The purpose of this investigation was to make a comprohensive study and evaluation of the oral health of a group of orthopedically handicapped children by considering the DMF rate, occlusion, and oral hygiene status of 194 orthopedic children. The obtained results were as follows. 1. The DMF rate of over all examined children was 59.85%, and when the four orthopedic groups were compared among themselves, it was found that Cerebral Palsy group had a significant higher DMF rate than that occuring in any of the remaining groups. 2. Total prevalence of malocclusion was 50. 10%, and it was found that Cerebral Palsied children had a significantly higher incidence of malocclusion ($67.90{\pm}4.12$), and that Cerebral Palsy group showed a significantly different distribution of higher percentage of Class II occlusions from that observed in the remaining groups. 3. In dental plaque index, Average plaque index per tooth was 2.09. Plaque index of each group was as follows A) Cerebral palsy: 2.35 B) Poliomyelitis: 2.24 C) Tb Group: 1.65 D) miscellaneous Group: 1.72.

• Journal of the korean academy of Pediatric Dentistry
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• v.23 no.3
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• pp.667-673
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• 1996

The prevalence of class III malocclusion is approximately 5$\sim$9%, and about one fourth of this malocclusion is due to underdeveloped maxilla. Maxillary protraction appliance is an orthopedic device which promote the growth of a deficient maxilla by applying extraoral force to actively growing patients. The object of using maxillary protraction appliance is to guide a normal growth of maxilla and mandible and improve the occlusal relationship and also improve the facial profile. The author treated three patients whom were diagnosed as a class III malocclusion due to deficient maxilla using maxillary protraction appliance and the followings are the conclusions : 1. In these cases, anterior crossbite was corrected by anterior movement of maxilla and downward backward rotation of mandible and simultaneously, anterior facial height was increased. 2. The amount of dental change compare to skeletal change was greater as the patients got older. 3. When 500gm of force to each side was applied, the treatment period has been decreased. 4. As a result of applying the force between maxillary first primary molar and canine, there was a small degree of changes in palatal plane. So, it can be concluded that the maxillary protraction appliance is effective in treating growing patients with a deficient maxilla.

• Journal of the korean academy of Pediatric Dentistry
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• v.10 no.1
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• pp.13-23
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• 1983

The purpose of this study was to make a comprehensive study and provide information about the oral status of handicapped. 874 (male: 540, female: 334) persons who are housed by 12 institution aged from 4 to 28 years in Seoul area was examined by considering the DMF rate, periodontal condition and occlusion. The obtained results were as follows: 1. Cerebral palsy, poliomyelitis, mental retardation, and blindness groups had a significant higher DMF rate than that occurring in any of the remaining groups. 2. Prevalence of periodontal disease in blindness, mongolism, cerebral palsy, poliomyelitis groups showed higher than that of the remaining groups. 3. Mongolism group had a significantly higher incidence of malocclusion (69.23%).

• Journal of Oral Medicine and Pain
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• v.32 no.1
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• pp.91-104
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• 2007

An epidemiologic investigation was carried out to determine the prevalence of symptoms of temporomandibular disorders in college students that aged 19-31 years. 460 students were investigated with a questionnaire from September to December 2006. The obtained results were as follows : 1. The prevalence of symptoms of temporomandibular disorders was 80.6%. 2. The most frequently complained symptom was headache and joint sound was the next one without distinct difference between men and women. 3. While the rate of occurrence of symptom of acute malocclusion decreased with age in men, that of TMJ pain during chewing or speech increased with age in women. 4. Symptoms including TMJ pain during mouth opening, chewing or speech, TMJ fatigue and acute malocclusion occurred significantly more frequently in women than in men. Contributing factors including resting cheeks on hands, stressful state, gum chewing, insomnia and clenching occurred significantly more frequently in women than in men. 5. There was a highly significant relationship between symptoms and contributing factors including resting cheeks on hands, stressful state, unilateral chewing, insomnia and clenching. 6. There was a highly significant relationship between symptoms and general personality.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.6 no.1
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• pp.19-22
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• 2010

Cerebral palsy is an umbrella term encompassing a group of non-progressive non-contagious motor conditions that cause physical disability in human development. Motor disorder of cerebral palsy is often accompanied by disturbances of sensation, perception, cognition, communication, behavior and seizure disorder. Disharmony of motor function leads to frequent falling down. Moreover patients have high prevalence of class II malocclusion. Compared to normal patients, the patients with cerebral palsy tends to have high prevalence of recurrent trauma and bruxism which make restoration of the anterior tooth more difficult. This case report is consisted of three cases of cerebral palsy patients who have challenging problems with restoration of anterior teeth.

• Journal of the korean academy of Pediatric Dentistry
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• v.41 no.3
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• pp.199-206
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• 2014

The number of reported traumatic injuries has been increasing in recent years, particularly that of dental trauma in children and adolescents. While the risks associated with dental trauma in this population have been increasingly realized, domestic reports on this issue seem to be insufficient. The purpose of this study was to investigate the prevalence of dental trauma and to evaluate the relevant risk factors and the level of self-recognition. 1,371 adolescents attending middle schools at Yangsan were surveyed via clinical examination and questionnaire; the results were as follows: According to the clinical examination, the overall prevalence of dental trauma was 16.8% with preponderance of males (19.2%) compared to females (13.7%) (p < 0.05). The average number of injured teeth per adolescent with a history of trauma was 1.34. Comparing the prevalence, maxillary central incisors and enamel fracture occupied the highest ranks by tooth type and mode of trauma, respectively. Class II division 1 malocclusion and overjet exceeding 8.0 mm were identified as significant risk factors (p < 0.05). The degree of self-recognition of dental trauma showed a low coincidence rate compared with results of the clinical examination. Males expressed a higher level of satisfaction toward the results of treatment for dental trauma than females (p < 0.05).