• The korean journal of orthodontics
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• v.38 no.5
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• pp.358-370
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• 2008

Objective: The purpose of this study was to investigate the horizontal skeletal pattern and dental arch differences between Class III malocclusion patients and normal occlusion patients. Methods: Twenty skeletal Class III malocclusion patients and ten normal occlusion patients were selected and 3D facial CT were taken to analyze the horizontal skeletal differences between the two groups. Results: In the horizontal comparison of the maxilla, skeletal width and perimeter were significantly smaller in skeletal Class III patients on ANS and A point reference planes. The difference between maxillary width of ANS and A point reference planes showed that there was greater constriction of the first and second premolar in skeletal Class III patients. In the horizontal comparison of the mandible, the widths of the canine and premolar area were significantly larger in skeletal Class III patients on B point reference plane. The differences between width of the upper and lower jaws (comparison of A and B reference planes) were significantly large in the canine and premolar area. Conclusions: From this study, the characteristics of Class III malocclusion patients were shown through horizontal constriction of the maxilla. But to make clear further detailed characteristics of Class III malocclusion patients, additional studies are necessary.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.2
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• pp.323-330
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• 1999

It is well recognized that a cross-bite tends to occur more frequently among Japanese, Chinese and Koreans more than among Europeans. A variety of functional appliances have already invented for the treatment of cross-bites. One of them is the FR III(by Rolf $Fr\ddot{a}nkel$) which applies a quite different philosophy based on the using vestibular region compared with other methods which utilize muscular forces applied directly on the teeth. The FR III also increases both the lack of muscular tension against the dental arch and the dentition and muscular forces which can then influence the teeth indirectly. This mechanism can achieve favorable developments with the basal bone, teeth, and alveolar bone. After using FR III to the anterior cross-bite patient with the eruption of a maxillary incisor the results were as follows: 1. Forward growth of maxilla and proclination of the upper incisor 2. Downward and backward rotation of the mandible 3. Increase the facial height 4. The case which was normal mandible, underdevelopmental maxilla, deeper overbite and more nagative overjet exhibited good prognosis

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.3
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• pp.473-480
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• 2007

The dentigerous cyst originates through alteration of stellate reticulum after amelogenesis has completed, with accumulation of fluid between the layers of the reduced enamel epithelium or between this epithelium and the tooth crown. Its incidence is relatively high on 10s or 20s of age and it is always related to the unerupted crown. Generally, it has no symptom, however, if the cyst is large or accompanied with pus formation, swelling and pain may occur. In radiographic findings, it shows impacted crown surrounded by well defined unilocular radiolucent lesion and occasionally displacement of adjacent teeth or root resorption. The goal of treatment is complete elimination of abnormal tissue preserving the tooth involved in the cyst. Enucleation and marsupialization are commonly used for the treatment. Marsupialization is the procedure which removes the partial portion of the cystic wall and connects with the oral mucosa. As the pressure in the cyst decreases, bone regeneration takes place in the defect area and cystic wall converts into normal mucosa. This procedure, however, is the most conservative procedure which allows the protection of adjacent important structures. If the eruption space is sufficient, then inducing the eruption of the permanent tooth in the cyst is also possible. In following cases, dentigerous cyst was diaganosed after clinical and radiographic examination. Marsupialazation was done to remove the cyst and induce the tooth, which was in the cyst, to erupt into the oral cavity.

• The korean journal of orthodontics
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• v.28 no.5 s.70
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• pp.717-729
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• 1998

This study was done to estimate arch forms and dimensions at the bracket level where archwire was placed in Angle's Class I first premolars extraction cases. 60 post-treatment dental casts which had attained good orthodontic treatment results were used in this study Many landmarks and linear measurement items to describe arch forms and dimensions were determined and measured. With a computer system and digitizer, arch forms were described and linear measurement items were statistically analysed. The following results were obtained. 1. The average labial and lingual arch forms at the bracket level were obtained. 2. Arch forms were expressed by parabolic equations and coefficients of determination. 3. Arch widths were larger in male than in female. 4. There were statistical significances in upper intercanine width, upper interfirst molar width, upper intersecond molar height, lower intercanine width and lower interfirst molar width between both sexes (p<0.05, p<0.01). 5. Interfirst molar width differences between maxilla and mandible were 6.43mm in male and 6.05mm in female.

• The Journal of Korean Academy of Prosthodontics
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• v.58 no.4
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• pp.342-348
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• 2020

Anatomical changes in the facial and alveolar bones occur after multiple teeth are extracted. In the maxilla, the alveolar bone is absorbed in the direction and inclination of the root, and the remaining alveolar bone becomes shorter, reducing the diameter of the arch. In addition, as the nasolabial angle increases, the support of the lips and the aesthetics of the face are lost. This case reports a functional and aesthetically satisfactory results of full mouth rehabilitation with the implant-supported fixed prosthesis using a zirconia framework.

• The korean journal of orthodontics
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• v.32 no.2 s.91
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• pp.91-105
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• 2002

In general, orthodontists make problem lists and treatment plans based on norms of several cephalometric standards. But consideration of dentoalveolar compensation, which tends to maintain normal dental arch relationship in various skeletal jaw relationships, helps orthodontists make more individualized treatment objectives and plans. The purpose of this study was to classify skeletal patterns of normal occlusion samples by cluster analysis and to investigate the dentoalveolar compensation according to skeletal patterns. The subjects were consisted of 125 subjects who were normal occlusion samples at Seoul National University Dental Hospital, Department of Orthodontics. Lateral cephalograms in centric occlusion were traced and digitized. The skeletal patterns of normal occlusion samples were classified into three horizontal groups and three vertical groups by cluster analysis and ANOVA on the skeletal and dentoalveolar measurements among the groups were carried out. The results were as follows ; 1. Anteroposterior and vertical skeletal relationships of normal occlusion samples were very variable. 2. As the mandibular position was anterior to the maxilla, the maxillary incisors inclined more labially, the mandibular incisors more lingually, and the occlusal plane was flattened due to the anteroposterior dentoalveolar compensation. dentoalveolar height was decreased and upper posterior teeth was uprighted to the palatal plane and lower incisors and lower posterior teeth to the mandibular plane. 4. Lower incisors were more strongly associated with the dentoalveolar compensation than upper incisors according to the anteroposterior and vertical skeletal relationship.

• The Journal of Korean Academy of Prosthodontics
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• v.49 no.1
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• pp.22-28
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• 2011

Purpose: This article attempted to examine how teeth for restoration is made in a clinical practice and utilize it as future educational material of teeth formation and basic data for additional research. Materials and methods: This experiment investigated the models sent to milling center for production of zirconia crowns. After scanned with Lava CAD/CAM System (3M ESPE, Seefeld, Germany), they are measured on 'ImageJ (version 1.32j, National Institutes of Health, USA)' program and compared and analyzed. Convergence angle from mesio-distal surfaces and bucco-lingual surfaces of each teeth are measured. Also, bucco-lingual diameter of the region lowered as much as 0.4 mm from incisal edge in anterior teeth except canines.(This measure is defined as the Peak 0.4) The analysis of data between each group was conducted by Windows SPSS statistic program, and was proved significant on 95% confidence level by independent t-test, one-way ANOVA and multiple analysis (Sheff${\'{e}}$ test). Results: The mean value of convergence angle was $18.67^{\circ}$ It is ranked as molar ($26.70^{\circ}$) > premolar ($16.87^{\circ}$) > anterior teeth ($14.81^{\circ}$) in the order of mesio-distal convergence angle; anterior teeth ($22.32^{\circ}$) > molar ($20.93^{\circ}$) > premolar ($15.41^{\circ}$) in the order of bucco-lingual convergence angle. The mean value of Peak 0.4 was 1.18 mm. Conclusion: Convergence angle of abutment of zirconia all ceramic crown has difference depending on the location in the arch. Due to the nature of production of zirconia all ceramic crown, convergence angle of abutment and line angle finishing degree can have an effect on internal suitability of restoration.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.1
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• pp.180-184
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• 2001

Cleidocranial Dysplasia(CCD) is an autosomal dominant human bone disease characterized by abnormal clavicles, patent sutures and fontanelles, and dental anomalies. Among dental anomalies, it is characterized that permanent dentition is severly disturbed due to multiple supernumerary teeth and abnormalities of tooth morphology. A eight-year-old female patient diagnosed as cleidocranial dysplasia visited in our hospital. Upon clinical oral exam, retained deciduous teeth, constriction of dental arch, anterior cross bite, and multiple dental caries were observed. In the dental panoramic radiograph, retained deciduous teeth and multiple supernumerary teeth in the maxilla and the mandible were found. In the cephalometric radiograph, open sutures and wormian bones were seen. In the chest P-A view absence of clavicles was observed. The cleidocranial dysplasia patients have eruption problems in permanent dentition both in regions with and without supernumerary teeth. The severely delayed or arrested eruption of permanent teeth has been ascribed to various factors : 1) The presence of multiple supernumerary teeth, 2) malformed roots with lack of cellular cementum, 3) the jaw bone being too dense, and 4) abnormal resorption of bone and primary teeth. Formation and maturation of primary teeth in cleidocranial dysplasia are normal, whereas the permanent dentition has various anomalies. Therefore, dentists should understand the development of dentition in cleidocranial dysplasia, and treat them in proper time.

• Journal of the korean academy of Pediatric Dentistry
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• v.38 no.3
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• pp.303-308
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• 2011

Tooth impaction refers to situations in which the eruption is inhibited by some physical barriers in eruptive path and the tooth remains unerupted beyond the normal time of eruption. The etiology of impacted tooth is controversial, but ankylosis has been suggested probably as a leading role. Impacted primary molars may cause several problems such as space loss, tipping of adjacent teeth, supra-eruption of the antagonists, dislocation of succeeding premolar, cystic change and infection. As one of conventional treatments of impacted primary molars, early tooth extraction or surgical extraction following space regaining when there is space loss has been suggested. However, when they are in normal formation and not ankylosed, orthodontic traction following surgical exposure can be the choice of treatment. In this case, a 3-year-old boy was referred to the department of pediatric dentistry for the unerupted mandibular right second primary molar. After surgical removal of gingiva on the occlusal surface, orthodontic traction was performed. After treatment, we could get normal alignment of primary teeth and the opportunity for normal development of permanent teeth.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.3
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• pp.539-547
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• 2008

Apert syndrome is an autosomal dominant condition characterized by craniosynostosis, midface hypoplasia, and syndactyly of the hands and feet. It occurs in about 1 of every 65,000 to 160,000 births and is caused by a mutation in the fibroblast growth factor receptor 2(FGFR2) gene. Apert syndrome typically produces acrobrachycephaly(tower skull). The occiput is flattened, and there is a tall appearance to the fore head. Ocular proptosis is a characteristic finding, along with hypertelorism and downward slanting lateral palpebral fissures. The middle third of the face is markedly retruded and hypoplastic, resulting in a relative mandibular prognathism. The reduced size of the nasopharynx and narrowing of the posterior choana can lead to mouth breathing, contributing to an open-mouth apprance. Three fourths of all patients exhibit either a cleft of the soft palate or a bifid uvula. The maxillary hypoplasia leads to a V-shaped arch and crowding of the teeth. A 6-year-old male patient visited to the Department of Pediatric dentistry, Kangnung National University of Dental Hospital. He visited the hospital to get treatment of carious teeth. The purpose of this report is to present a specific dental manifestations about the apert syndrome.