• The korean journal of orthodontics
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• v.33 no.4 s.99
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• pp.259-277
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• 2003

This study was designed to investigate the position of anteroposterior center of resistance for genuine intrusion and the mode of change of the minimum distal force for simultanous intrusion and retraction of the upper and lower incisors according to the increase of labial inclination. For this purpose, we used the three-piece intrusion arch appliance and three-dimensional finite element models of upper and lower incisors. 1. Positions of the center of resistance in upper incisors according to the increase of the labial inclination were as follows; 1) In normal inclination situation, the center of resistance was located in 6m behind the distal surface of the lateral incisor bracket. 2) In $10^{\circ}$ increase of the labial inclination situation, the center of resistance was located in 9mm behind the distal surface of the lateral incisor bracket. 3) In $20^{\circ}$ increase of the labial inclination situation, the center of resistance was located in 12m behind the distal surface of the lateral incisor bracket. 4) In $30^{\circ}$ increase of the labial inclination situation, the center of resistance was located in 16m behind the distal surface of the lateral incisor bracket. 2. Positions of the center of resistance in lower incisors according to the increase of the labial inclination were as follows; 1) In normal inclination situation, the center of resistance was located in 10mm behind the distal surface of the lateral incisor bracket. 2) In $10^{\circ}$ increase of the labial inclination situation, the center of resistance was located in 13m behind the distal surface of the lateral incisor bracket. 3) In $20^{\circ}$ increase of the labial inclination situation, the center of resistance was located in 15m behind the distal surface of the lateral incisor bracket. 4) In $30^{\circ}$ increase of the labial inclination situation, the center of resistance was located in 18m behind the distal surface of the lateral incisor bracket. 3. The patterns of stress distribution were as follows; 1) There were even compressive stresses In and periodontal ligament when intrusion force was applied through determined center of resistance. 2) There were gradual increase of complexity in compressive stress distribution pattern with Increase of the labial inclination when intrusion and retraction force were applied simultaneously. 4. With increase of the labial inclination of the upper and lower incisors, the position of the center of resistance moved posteriorly. And the distal force for pure intrusion was increased until $20^{\circ}$increase of the labial inclination.

• The korean journal of orthodontics
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• v.22 no.3 s.38
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• pp.735-753
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• 1992

The purpose of this study was to analyze the positions of upper and lower incisors according to facioskeletal patterns. The lateral cephalometric radiographs of sixty persons with normal occlusion, forty persons with Class II Division 1 malocclusion, and forty persons with Class III malocclusion all above the age of 18, were analyzed. The following results were obtained. 1. C I angle, the measurement related to masticatory system, were $89.20{\pm}4.34^{\circ}$ in normal occlusion group, $81.68{\pm}士5.95^{\circ}$ in Class II Division 1 malocclusion group and $101.96{\pm}6.31^{\circ}$ in Class III malocclusion group. 2. In comparison with the positions of upper and lower incisors according to facioskeletal patterns, Class II Division 1 malocclusion group showed that upper incisors were different significantly in all measurements and inclined labially (P < 0.05). Lower incisors were different significantly in all measurements except LI-APog, LI-APog (mm), LI-AB, LI-AB (mm) and inclined labially (P < 0.05), Class III malocclusion group showed that upper incisors were different significantly in all measurements except UI-SN, UI-OP, and inclined labially (P < 0.05). Lower incisors were different significantly in all measurements and inclined lingually (P < 0.05). 3. In all facioakeletal patterns, LI-SN and LI-PH ware correlated moderately to facioskeletal measurements, and FMA was correlated moderately to measurements of lower incisor position. 4. Regardless of the facioskeletal patterns, the reference planes equally applicable were AB line in the measurements of upper incisor and APog line in the measurements of lower incisor.

• Journal of Oral Medicine and Pain
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• v.9 no.1
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• pp.157-167
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• 1984

A human bite-mark shows special feature according to the suspect's dentition. The teeth which most frequently give useful bite-marks are six upper and lower anteriors, while the premolar teeth somtimes give marks it is often difficult to distinguish. The author tried to classify and to analize the anterior dentition which makes the bite-mark directly by means of 672 maxillary and 691 mandibular stone model taken from Korean adult aging from 17 to 40 years old. The results were as follows : 1. There was no particular correlation between the presence of six normal-shaped and correctly positioned upper and lower anteriors and the presence of rotation of teeth. 2. Inter central incisor, inter lateral incisor, inter canine width and angles of adjecent teeth were not identical eath other in studied models. 3. The results of this analysis supported the statement that any bite-mark had no same feature.

• The korean journal of orthodontics
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• v.28 no.1 s.66
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• pp.99-111
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• 1998

The purpose of this study was to evaluate the positioning errors according to the method of bonding lingual brackets. Dental models of twenty orthodontic patients with malocclusion were selected for this study. The positioning errors were measured on each model that brackets were bonded to. Three different bonding methods were used. For the first method the bracket was bonded intimately to the lingual surface of the model. For the second method, the bracket was bonded intimately to the lingual surface after setting up using articulator. The passive bracketing, bonding the bracket ligated first to ideal archwire, was used after setting up as the last method. The results were as follows: 1. The brackets bonded without setting up showed greater angulation errors in the upper 1st premolar and the lower canine than those in other bonding methods. The brackets bonded without passive bracketing showed greater positioning errors in upper central incisor, lower 1st and End premolars. 2. The brackets bonded without setting up showed greater torque error in lower 2nd premolar than those in other bonding methods. The brackets bonded without passive bracketing showed greater torque errors in all upper teeth, lower 1st and 2nd premolars. 3. The brackets bonded without passive bracketing showed greater rotation errors between upper central incisors, lower central incisors, lower lateral and central incisor, lower canine and lateral incisor. 4. The brackets bonded without setting up showed greater in-out errors between upper canine and lateral incisor than those in other bonding methods. The brackets bonded without passive bracketing showed greater in-out errors between upper central incisors, upper central and lateral incisors, upper 1st and 2nd premolars, lower lateral and central incisors, lower canine and lateral incisor. These results suggest that there is a large amount of positioning error in lingual brackets even by an indirect bonding technique, and it may be reduced by passive bracketing.

• The korean journal of orthodontics
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• v.6 no.1
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• pp.71-77
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• 1976

19 years old female had untreated Veau classification class II cleft palate with ectopic eruption of upper right lateral incisor and congenital missing of lower lateral incisors. Upper left lateral incisor, left first molar aid lower left first molar were root restswithperiapicalpathologiclesions. So all root rests were extracted and prosthodontic rehabilitation after orthodontic treatment was planned. She was treated by means of multibanded system with face bow. After 23 months all orthodontic correction were achieved and, as soos as debanding procedure was done she was referred to oral surgeon and prosthodontist for surgical operation and bridge construction.

• The korean journal of orthodontics
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• v.24 no.4 s.47
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• pp.759-772
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• 1994

Orthodontists have experienced the treatment of cases with three lower incisors. Occasionally a lower incisor was either congenitally missing or so seriously damaged by injury or disease that its removal presented the best prospect for the patient. Sometimes the intentional extraction of a lower incisor is needed to produce enhanced functional and esthetic results with minimal orthodontic manipulation. Such cases have unfavorable anterior tooth size discrepancies and present difficulties in achieving good occlusal results. However such difficulties can be overcome by the sensible diagnosis and treatment plan. Three different cases are presented and the conclusions are listed. 1. It is important for orthodontist who tries to treat three lower incisor cases to measure and calculate accurately the degree of deviation of tooth size and morphology and the anterior tooth size ratio. 2. A diagnostic setup model should be made to determine whether the incisor extraction is appropriate and space closure is needed or not. It is the best way to be sure that the occlusal results, including overbite and overjet, will be acceptable and how far the degree of midline deviation is. It also shows the amount of interproximal reduction to achieve an acceptable occlusal result. 3. The class I relationship between the upper canine and the lower one must be obtained to establish the canine rise during eccentric movement by the concept of mutually protective occlusion. It also helps to maintain the stable occlusal result.

• Journal of the korean academy of Pediatric Dentistry
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• v.11 no.1
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• pp.145-150
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• 1984

Author have measured the depth of gingival sulcus of the primary teeth. 333 teeth were selected from the children who attended on the department of pedodontic, College of dentistry, Yonsei University, and kindergarten children at Won Ju city aged from 1 year 8 months to 10 year 2 months. 1998 point were measured. The results were as follows. ; 1. Facial surface was the shallowest in sulcus depth compared with other surfaces. It was 1.56 mm. The depth of sulcus in lingual surface was deeper than facial. 2. The deepest part of each surface was mesial and distal, There were no statistical differences between mesial and distal part of the sulcus depth. 3. The mean sulcus depth of each tooth was as follows. Primary central incisor.....1.71mm. Primary canine....1.75mm. Primary second molar.....2.03mm. 4. The mean sulcus depth of upper was 1.86mm, and the lower was 1.76mg. The upper tooth was deeper than lower in sulcus depth. 5. The lower primary central incisor had the shallowest sulcus and the upper 2nd primary molar had the deepest compared with other tooth. 6. There wasn't specific statistical differences between the age groups of primary dentition and mixed dentition.

• The korean journal of orthodontics
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• v.6 no.1
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• pp.55-63
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• 1976

This study was undertaken to establish the roentgenocephalometric standards of the Korean children in Hellman dental age III C. The subjects consisted of 33 males and 33 females with the normal occlusion and acceptable profile. The lateral cephalometric films were taken with the teeth in centric occlusion, the soft tissue outline of the nose, lips, and chin was made visible by the low-speed films, 70Kvp, 100Mas. Their linear and angular measurements were performed by Jarabak's methods. The following results were obtained; 1) The author made the tables of standard deviation from the measured values. 2) Each linear measurement of the skull was greater in males than in females. 3) The maxillary basal bones were more protrusive in Korean children than in Caucasian. 4) The degree of the facial convexity was larger in Korean children than in Caucasian. 5) The labial inclination of the upper & lower incisors was greater in Korean children than in Caucasian. The labial inclination of the upper incisor was greater in females, but the labial inclination of the lower incisor was greater in males.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.4
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• pp.547-552
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• 2001

Extracting mandibular incisors for orthodontic treatment may adversely affect the occlusion. However, when properly used, extraction of mandibular inciors is a selection for the correction of the malocclusion. Generally, treatment for crowding needs to select between nonextraction and four premolar extraction. Approaches for crowded mandibular incisors include distal movement of posterior teeth, lateral movement of canines, labial movement of incisors, interproximal enamel reduction, removal of premolars, removal of one or two incisors, and various combinations of the above. Extraction of incisors is used in case of crowding, anterior tooth size discrepancy, absent of maxillary lateral incisors, and ectopic eruption. But severe overjet. overbite, and space are the contraindication of it. A patient had severe crowding on upper anterior teeth, impacted upper left lateral incisor, palatal ectopic eruption of upper right incisor and severe crowding on lower anterior teeth. Lower lateral incisors are extracted for space availability and facial esthetics. We report the case of orthodontic treatment of upper and lower anterior crowding through extraction of lateral incisor.

• The Journal of Korean Academy of Prosthodontics
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• v.43 no.1
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• pp.41-51
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• 2005

Statement of problem. Anatomic landmarks have been used in the orientation of occlusal plane and the determination of vertical dimension for edentulous patients. Such as labial vestibules of anterior region and hamular notches, retromolar pads of posterior region are very useful anatomic landmarks for fabrication of occlusion rim because they are to be identified on master casts. Therefore, if average distances between landmarks of maxillae and mandible in dentate subjects are measured and applied, not only occlusal plane but also vertical dimension can be established initially. Purpose. The purpose of this study is to measure vertical distances between anatomic landmarks and to present a guide to the orientation of occlusal plane and the determination of vertical dimension of edentulous patients. Material and method. Upper and lower border-molded casts were made in 93 Korean dentulous subjects, mean age 25 years. Incisal edges of central incisors, bottoms of labial vestibules, hamular notches and the half level of retromolar pads were marked on casts. Measurements of vertical distances from incisal edge of central incisor to the bottom of labial vestibule, between upper and lower bottoms of labial vestibules, from hamular notch to retromolar pad and from hamular notch to the occlusal plane established by the incisal edge of maxillary central incisor and mesiopalatal cusps of both maxillary first molars were made on each cast. Results and conclusion. 1. The mean distance from the incisal edge of central incisor to the bottom of labial vestibule was 20.8mm(SD 1.7) on upper casts and 17.3mm(SD 1.4) on lower casts. 2. The mean distance between both bottoms of labial vestibules of upper and lower casts was 35.0mm(SD 2.7). 3 The mean distance from hamular notch to the half level of retromolar pad was 5.0mm(SD 1.3). 4. The mean distance from hamular notch to occlusal plane was 7.9mm(SD 1.5). 5. Distances from incisal edge of central incisor to labial vestibule on lower casts(P<0.01) and from hamular notch to retromolar pad(P<0.0001) were greater in male than in female.