• Journal of the Korean Academy of Esthetic Dentistry
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• v.7 no.1
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• pp.28-31
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• 1998

It is difficult to make an artificial central incisor similar to natural tooth. All ceramic porcelain of this patient is not esthetic, and there is gingival recession due to ill-fitted margin. She has class II division 1 occlusion, so upper central incisors is labioversed. Upper light central incisor is well-characterized but the yellowish brown color of dentin is appeared on the incisal third portion of the central incisor. At 1st trial, the shape and characterization of restoration is good but shade is little dark. At 2nd trial, the shape is better but patient complained on black triangle of mid interdental space, so mesiocervical portion of restoration is overcontoured to compromise the black triangle. Completed metal ceramic crown is in harmony with the adjacent central incisor in aspect of shape, shade, and characterization.

• The korean journal of orthodontics
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• v.43 no.4
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• pp.201-206
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• 2013

This article describes the orthodontic treatment of a 25-year-old Korean female patient with anterior crowding, including palatally displaced lateral incisors. Her facial profile was satisfactory, but 3.5 mm of maxillary anterior crowding was observed. To correct this crowding, we decided to minimize the use of the conventional fixed orthodontic appliances and employed a less bulky and more aesthetic appliance for applying light continuous force. We determined the final positions of the maxillary teeth via a working model for diagnostic set up and achieved space gaining and alignment with simple Ni-Ti spring and stainless steel round tubes. Tooth alignment was achieved efficiently and aesthetically without the conventional brackets.

• The Journal of the Korean dental association
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• v.48 no.11
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• pp.803-812
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• 2010

Regenerative endodontic procedure (REP) is a treatment option to replace damaged pulp tissue with the viable tissue which restores the normal function of the pulp-dentin complex. Possible reason for doing REP is not clearly known, however, clinicians perform REP in order to recover the histological structure as well as function of the traumatized and diseased tooth so that this tooth can restore its original root shape and thickness. This REP can be explained by the concept of revascularization or revitalization after induction of blood clot formation in the canal space. For this purpose, several treatment strategies have been suggested. In this regard, the rationale for the application of triantibiotics, calcium hydroxide or mineral trioxide aggregate is discussed in this paper. As a result, we will try to find the best method for REP by reviewing each available technique and their advantages and disadvantages.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.3
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• pp.651-659
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• 1997

This report presents a case of adolescent patient who had multiple impacted teeth and no systemic disease, and was treated with removable and fixed orthodontic appliances. The results obtained through these cases were summarized as follows : 1. Even in the case without systemic disease, there can be the delayed eruption of multiple teeth 2. If the root formation is not completed, root have no excessive curvature, axial inclination of the tooth is not excessive, and there is eruption space, the tooth can be induced to normal occlusion. 3. Since esthetically proper occlusion and dentition was acquired by recovery of the impacted teeth to normal occlusion, the prosthodontic treatment after extraction of the impacted teeth was less needed. 4. This treatment brought psychological stability to pubertal patient who was interested in his facial profile.

• Journal of the korean academy of Pediatric Dentistry
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• v.3 no.1
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• pp.7-11
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• 1976

The author measured the degree of development and the eruption pattern of first permanent molars with orthopantomography in 553 Korean children(male; 302, female; 251) from 4 to 9 years old. The orthopantomographs were obtained from dept. of pedodontics, college of dentistry, Seoul National University. The results of the studies were as follows: 1. Upper first permanent molars were erupted with distal inclination of about 30 degrees in the early stage and they gradually moved in the mesial direction by bodily movement of the tooth to be in contact with the disto-proximal surface of primary secondary molars in the late stage. 2. Lower first permanent molars were erupted with mesial inclination in the early stage and moved mesially by tipping movement of the tooth to be in contact with the disto proximal surface of the second primary molars in the late stage. 3. The eruptive forces were considered to be main etiologic factors of space closure after the premature loss of primary molars.

• The Journal of Korean Academy of Prosthodontics
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• v.31 no.3
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• pp.447-459
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• 1993

A two dimensional finite element model was constructed to analyze the mechanical behavior of four unit fixed partial dentures (FPD) with a 2nd premolar abutment either employing a rigid or nonrigid connector and a 2nd molar abutment(Branemark implant, IMZ implants and natural tooth). Gap elements were used to model the clearance space of the nonrigid connectors and each components of implants. All FPDs with a implant abutment alter the patterns of stress distribution and displacement, but the magnitude of stress in the periodontium was not greater than that of the control. A FPD with rigid connectors induced the smaller stresses in the periodontium than a FPD with a nonrigid connector. A FPD with a Branemark implant exhibited the more desirable mechanical stress states as compared to the IMZ implants with IME or IMC.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.23 no.2
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• pp.155-162
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• 2001

This is a clinical study on patients who had visitied the Emergency Room of Pusan National University Hospital and then been treated in the Department of Oral and Maxillofacial Surgery during recent 5 years, from 1992 to 1996. The results were as follow ; 1. The total number of patients was 2,680 and the ratio of male to female was 1.96:1, The highest monthly incidence was shown in September(12.1%) and October(10.5%) and the age distribution peaks was the third decade(24.3%), followed by the first(23.1%) and the fourth decade(17.2%). 2. Soft tissue injury group(29.1%) was the most prevalent, followed by tooth injury group(16.1%), facial bone injury group (16.0%), toothache group(11.2%), socket bleeding group(11.1%), infection group(9.8%) and TMJ dislocation group(5.9%). 3. The percentage of in-patients and out-patient were 21.6% and 78.4%, respectively. The frequent causes of admission were facial bone fracture(73.8%), infection(20.8%) and soft tissue injury(4.8%) in order. However, soft tissue injury was the most frequent cause in out-patient, followed by tooth injury(20.5%), toothache(14.3%), socket bleeding(14.2%) and TMJ dislocation(7.6%). 4. In the facial bone injury group, the mandibular fractures(70.6%) showed the highest incidence, followed by zygomatic bone and arch fractures(7.5%), maxillary bone fractures(4.0%) and nasal bone fractures(4.0%). 5. In the mandibular bone fracture, the most common location was symphysis(36.7%), followed by the mandibular angles(33.1%) and the condyles(21.8%). 6. The common causes of facial bone fractures were violence, fall and traffic accident in order. 7. The common causes of soft tissue injury were fall down, fight and traffic accident in order and the highest incidence was observed in infants before the age of 10 years(44.0%). 8. In the group of tooth injury, tooth luxation(38.5%) showed the highest incidence followed by tooth fracture(33.2%) and tooth loss(17.1%). The common causes of tooth injury were fall, fight and traffic accident in order. 9. In infected patients group, the ratio of in-patients to out-patients was 1 : 1.28, Buccal(24,7%) and infraorbital space abscess(23.3%) showed the highest incidence. 10. The pain caused by dental caries(39.0%) and pericoronitis(26.6%) showed high incidence in the toothache group. 11. The high incidence was observed during third(34.0%) and fourth (24.5%) decades in TMJ dislocation group. 12. In the group of socket bleeding patients, 92% was post-operative hemorrhage and 8% was accompanied with other systemic hemorrhagic diseases.

• The Journal of Korean Academy of Prosthodontics
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• v.57 no.4
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• pp.405-415
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• 2019

Excessive tooth wear can cause irreversible damage to the occlusal surface and can alter the anterior occlusal relationship by destroying the structure of the anterior teeth needed for esthetics and proper anterior guidance. The anterior deep bite is not a morbid occlusion by itself, but it may cause problems such as soft tissue trauma, opposing tooth eruption, tooth wear, and occlusal trauma if there are no stable occlusal contacts between the lower incisal edge against its upper lingual surface. The most important goal of treatment is to form stable occlusal contact in centric relation. In this case report, patients with decrease in vertical dimension and anterior deep bite due to maxillary posterior tooth loss and excessive tooth wear were treated full mouth rehabilitation with increased vertical dimension to regain the space for restoration and improve anterior occlusal relationship and esthetics. The functional and aesthetic problems of the patient could be solved by the equal intensity contact of all the teeth in centic relation (CR), anterior guidance in harmony with the functional movement, and restoration of the wear surface beyond the enamel range.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.8
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• pp.1029-1033
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• 2013

Elliptical gear is used as a rotor of oval flowmeter. The elliptical gear can assist water flow-rate measurement by the space of the elliptical shape. Presently, elliptical gears have been processed using hob tool imported from Japan. But if it were not for the technical cooperation with Japan company, the Elliptical gears can't be processed. The purpose of this study is developing a domestic technology for elliptical gears and overcoming the dependence of foreign technical skills. It will bring the import substitution effect. In case of pressure angle $20^{\circ}$, the elliptical gears have an interference of tooth. The increase of pressure angle makes the root of a tooth thick and the top of tooth thin. By results of this study, tooth of elliptical gear was designed and verified through the 2D and 3D simulation.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.2
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• pp.219-227
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• 2020

Tooth eruption involves a complex developmental process of tooth migration from the dental follicular origin to the final occlusion position in the oral cavity via the alveolar process. Disturbance of tooth eruption can occur at any point in a series of eruption stages; however, horizontal impaction of the mandibular first molar and primary retention of the primary mandibular second molar are rarely observed simultaneously. This study describes the treatment for two cases of horizontally impacted first molar with primary retention of primary molar. The primary retention of the primary mandibular second molar was extracted, and orthodontic traction was applied to the horizontally impacted primary mandibular first molar. Subsequently, displacement of the premolar tooth bud was improved and space regaining for eruption was achieved, guiding to normal eruption of the first molar.