• The korean journal of orthodontics
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• v.22 no.3 s.38
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• pp.509-529
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• 1992

Skeletal Class III malocclusion is one of the most difficult type to treat and stabilize. For a child with developing skeletal Class III malocclusion, the treatment objective would be to stimulate maxillary growth, particulary one who has markedly deficient maxilla, and to restrain excessive mandibular growth. In order to stimulate the maxillary growth, maxillary protraction appliance is the one of the effective orthopedic appliances in skeletal Class III. The purposes of this study were as follows ; evaluation of the skeletal and dental changes of the maxillary protraction in children with Class III Maxillary deficiency , comparison of the clinical effects between the group with RPE and labiolingual intraoral appliances , comparison of the clinical effects and stability related to the ages of the patients : stability of the maxillary protraction about 1 year after retention. The subjects consisted of 60 children between the ages of 8 and 13.4 who were diagnosed as Class III with maxillary deficiency and were treated with Face Mask (Delaire Type) from the Dept. of Orthodontics Yong Dong Severance Hospital, Yonsei University. 48 children wore the RPE and 12 children wore Labiolingual Appliance. Lateral Cephalograms were taken for each patient at before and after correction of anterior cross-bite in 60 children, and after an observation period of 10 to 14 months in 19 children. X and Y coordinate of 10 landmarks were analyzed using a horizontal line through sella and rotated $6^{\circ}$ down anteriorly as the horizontal reference axis, and a perpendicular verticual line through sella as the vertical reference axis. Each of the 31 measurents (10 verticals, 10 horizontals, 2 angles and 9 others) was statistically analyzed using SPSS/PC statistics. The results are as follows; 1. After maxillary protraction the maxilla and maxillary teeth moved downward and forward, while the mandible and mandibular incisor rotated downward and backward. 2. Maxillary protraction with rapid palatal expansion appliance was more effective than with labiolingual appliance. 3. More downward movement of the posterior palatal plane obserbed with maxillary protraction doing the midpalatal suture opening than with protraction after finishing the palatal expansion 4. The clinical effects of protraction and changes of the retention periods were not statistically significant among the age groups. 5. During the retention period, maxilla and maxillary teeth, and mandible and mandibular teeth moved downward and forward, however the mandibular changes were larger than the maxillary changes.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.1
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• pp.95-101
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• 2013

Recently, the demand for esthetic improvement by a treatment neither time consuming nor invasive is increasing. The patient wanted the maxillary anterior teeth appearance to be improved by prosthetic treatment, not other treatments such as orthodontic, periodontal, and endodontic treatments, despite the limit of esthetic improvement. In this case, among the recent variety of all ceramic systems for the aesthetic prosthetic restoration, we selected the zirconia-based system as a method of restoration in order to conceal the discoloration of teeth. The patient was satisfied with the esthetic results.

• The Journal of Korean Academy of Prosthodontics
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• v.21 no.1
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• pp.67-72
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• 1983

Path of insertion(1) can be defined that the direction of movement of an appliance from the point of initial contact of its rigid parts with the supporting teeth to the place of final rest. Krol(2) described that in the conventional path of insertion, all the rests are seated more or less simultaneously but in the use of the rotational path one segment of the partial denture is seated first then the remainder of the prosthesis is rotated into position. The rotational path of insertion is limited primarily to the tooth borne prosthesis. Its great advantages are the elimination of anterior clasps to improve ethetic and reduction of tooth coverage to minimize plaque accumulation. Either a rigid minor connector or proximal plate provides retention through its intimate contact with a proximal tooth surface below the height of contour as indicated at a o-degree tilt. A specially designed rest in conjunction with this retentive component satisfies the basic requirements of clasp design. The purpose of this study was a clinical evaluation of rotational path removable partial dentures. Author delivered rotational path removable partial dentures to three different cases of patients and evaluated function of the dentures, difficulties of removal and insertion of the dentures and supporting structures of the abutment teeth by means of clinical and X-ray examinations for eighteen months. According to the examination data author came to the conclusion that the prognosis of the rotational path removable partial dentures was excellent.

• The korean journal of orthodontics
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• v.47 no.6
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• pp.365-374
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• 2017

Objective: The objective of this study is to investigate the eruption pattern and root resorption of the bovine anterior dentition in relation to growth-related parameters based on dental maturity. Methods: A cross-sectional study was conducted on 110 bovine anterior mandibles by using standard radiography, cone-beam computed tomography (CBCT), and actual measurements. We determined the relationships between the stages of dental maturity by using a modification of Demirjian's method and various growth-related parameters, such as the activity of the root-resorbing tissue and mobility of the deciduous teeth. The correlation of growth-related parameters with interdental spacing and distal unusual root resorption (DRR) of the deciduous fourth incisor was assessed. The cause of mesial unusual root resorption (MRR) of the deciduous fourth incisor was determined on the basis of the arrangement of the permanent third incisor. Results: An independent t-test and chi-square test indicated significant differences in growth-related parameters associated with dental arch length discrepancy and factors related to the shedding of deciduous teeth between the low and high dental maturity groups. The samples with interdental spacing and DRR showed a larger sum of mesiodistal permanent crown widths and higher dental maturity than did the respective controls. Samples with MRR tended to show a lingually rotated distal tip of the adjacent tooth crown. Conclusions: Dental maturity has relevance to the interdental spaces and unusual root resorption of mixed dentition. The position of the adjacent tooth crown on CBCT may be correlated with the occurrence of unusual root resorption of the incisor.

• The Journal of Advanced Prosthodontics
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• v.8 no.2
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• pp.125-130
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• 2016

PURPOSE. The purpose of this study was to determine the effect of changes in the horizontal plane angle on the mesiodistal width ratios of the maxillary anterior teeth during the acquisition of frontal view photographs, derive these ratios for Korean adults on the basis of the data obtained, and analyze them using the Golden Proportion as a reference. MATERIALS AND METHODS. In experiment I, 30 plaster casts were mounted on an articulator and positioned on the angle-measuring device with a center setting of $0^{\circ}$. The device was rotated to $10^{\circ}$ in $1^{\circ}$ increments in a counterclockwise direction. At each angle, photographs were obtained and analyzed. Experiment II was based on 60 patients who visited the Department of Prosthodontics at Kyungpook National University Dental Hospital from February 2012 to February 2015. The patients were divided into three groups [Male (M), Female (F), Total (M + F)]. Frontal views were obtained for all groups and analyzed. RESULTS. From $1^{\circ}$ to $10^{\circ}$, the relative mesiodistal width ratios for the maxillary anterior teeth showed no significant differences from those at $0^{\circ}$. In all three groups, the relative width ratio of the maxillary central incisor was smaller than that specified in the Golden Proportion; the opposite was true for the canine. CONCLUSION. Our results suggest that the mesiodistal width ratios of the maxillary anterior teeth do not follow the Golden Proportion in Korean adults, and that a change in the horizontal plane angle from $1^{\circ}$ to $10^{\circ}$ during frontal photography does not affect these ratios.

• The korean journal of orthodontics
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• v.46 no.5
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• pp.280-289
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• 2016

Objective: The aim of this study was to analyze tooth movement and arch width changes in maxillary dentition following nonextraction treatment with orthodontic mini-implant (OMI) anchorage in Class II division 1 malocclusions. Methods: Seventeen adult patients diagnosed with Angle's Class II division 1 malocclusion were treated by nonextraction with OMIs as anchorage for distalization of whole maxillary dentition. Three-dimensional virtual maxillary models were superimposed with the best-fit method at the pretreatment and post-treatment stages. Linear, angular, and arch width variables were measured using Rapidform 2006 software, and analyzed by the paired t -test. Results: All maxillary teeth showed statistically significant movement posteriorly (p < 0.05). There were no significant changes in the vertical position of the maxillary teeth, except that the second molars were extruded (0.86 mm, p < 0.01). The maxillary first and second molars were rotated distal-in ($4.5^{\circ}$, p < 0.001; $3.0^{\circ}$, p < 0.05, respectively). The intersecond molar width increased slightly (0.1 mm, p > 0.05) and the intercanine, interfirst premolar, intersecond premolar, and interfirst molar widths increased significantly (2.2 mm, p < 0.01; 2.2 mm, p < 0.05; 1.9 mm, p < 0.01; 2.0 mm, p < 0.01; respectively). Conclusions: Nonextraction treatment with OMI anchorage for Class II division 1 malocclusions could retract the whole maxillary dentition to achieve a Class I canine and molar relationship without a change in the vertical position of the teeth; however, the second molars were significantly extruded. Simultaneously, the maxillary arch was shown to be expanded with distal-in rotation of the molars.

• Journal of the korean academy of Pediatric Dentistry
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• v.10 no.1
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• pp.115-122
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• 1983

The author surveyed 2,082 schoolchildren (Male: 1,078, Female: 1,004) from 7 to 12 years old in "N" primary school in kwang Ju City, and studied on 304 schoolchildren (Male: 176, Female: 128) having maxillary median diastema. The results were as follows: 1. The prevalence of maxillary median diastema was 14.6%, and it showed the greater rate at the boys than at the girls and the highest rate at 8 years old in the both sexes. 2. The maxillary median diastema showed decreasing tendency with ageing. 3. The frenum distance in children without local factors showed no change and the divergent degree of maxillary median diastema showed decreasing tendency after the eruption of maxillary lateral incisors. 4. The rate of maxillary median diastema associated with local factors was 37.8% and it showed increasing tendency with ageing. 5. The prevalence of median diastema according to etiology was as follows; rotated tooth; 12.2%, supernumerary teeth; 10.9%, abnormal frenum; 9.5%, peg lateralis; 7.2%, open bite; 2.6%, abnormal pattern of interseptal alveolar bone; 2.6%, missing lateral incisor; 0.7%, tooth size discrepancy; 0.3%.

• Journal of Korean society of Dental Hygiene
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• v.10 no.3
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• pp.523-530
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• 2010

Objectives : In order to provide basic data necessary for developing oral health education plane for school continued oral health education by understanding knowledge and activities of oral health. Methods : This study was performed against 324 students at 5th grade of 2 elementary schools in Iksan-si, Jellabuk-do selected through convenience sampling, who were in mixed dentition period that might experience dental caries of permanent tooth. Results : As results, For the knowledge level on oral health by questions, it was found that the case that the elementary school students had correct knowledge on oral health was 'chocolates, snacks, and candies were foods that might often cause dental caries' and 95.8% of the students recognized it well. It was found that for 'must do toothbrushing before going to bed', 'during toothbrushing, I clean my tongue', and 'Proper time necessary for toothbrushing is about 3 minutes', 89.3%, 93.2%, and 89.3% of the students knew the, respectively. When oral health knowledge level by groups was divided into 3 groups and observed, they were classified into Low (0-4 points), Mid (5-7 points), and High (8-10 points). It was found that the knowledge level of each group was High 64.1%, Mid 33.9%, and Low 2.0% and it was identified that the high group took the largest ratio. It was suggested also for oral health knowledge level depending on their father's academic background that there was a statistically significant difference in the group higher than university graduate(p<.05). It was found for oral health knowledge level depending on parents' dental condition that an answer that both parents were good was high and there was a statistically significant difference. But post-analysis resulted that there was no apparent difference among groups. It was found that the ratio of respondents who answered for toothbrushing method 'toothbrush should be moved and rotated downward for the upper teeth and upward for the lower teeth to clean the teeth and gum' were 33.2% of male students and 29.4% of female students and showed statistically significant difference (p<0.05). It was found also that the ratio of respondents who answered to use a toothbrush for about 3 months' were 29.4% of male students and 25.5% of female students and showed statistically significant difference (p<0.05). Conclusions : Oral health program through the elementary school students and their parents for the development of proper oral health care education programs continue to be made should be considered.

• Journal of Yeungnam Medical Science
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• v.8 no.1
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• pp.198-205
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• 1991

We obtained successful functional and esthetic results by grafting of iliac marrow-cancellous bone in 2 cases of alveolar-palatal cleft patients. Bone graft of alveolar-palatal clefts provide bony support to adjacent teeth of cleft area, prevented from relapse of orthodontic arch expansion, closure of oroantral fistula and improvement of speech problem. 1. In one case, extraction of upper right central incisor that was little bone support, alignment of rotated teeth and expansion of collapsed arch segment were done with pre-ortodontic treatment. The other case, Bone grafting was done after removal of prosthesis with no preorthodontic treatment. 2. After mucoperiosteal incision in cleft area. The mucosal flap of labial area, palate and nose were separation and the raised nasal mucosa was sutured for closure of oroantral fistula. Then, the iliac marrow-cancellous bones were grafted to cleft site. 3. After 6 months of operation, we had seen the new bone deposition to cleft site in dental radiography and prosthetic treatments of missing teeth were done.

• The korean journal of orthodontics
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• v.17 no.2
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• pp.185-200
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• 1987

This paper was undertaken to observe the displacement of craniofacial complex with cervical headgear and to compare narrowing or widening effect of palate by use of contraction or expansion face-bow, respectively. The 3-dimensional finite element method(FEM) was used for a mathematical model composed of 597 nodes and 790 elements and an electrical resistance strain gauge investigation was performed to validate the finite element model. The outer bow of cervical headgear was adjusted to be placed below the occlusal plane by $25^{\circ}$ and met the midsagittal plane by $40^{\circ}$, and was loaded 1kg on each right and left hook toward posterior direction. The results were as follows 1. Generally, the maxillary teeth and facial bone were displaced in posterior, medial and downward direction. 2. It was the maxillary 2nd bicuspid that moved bodily. 3. The craniofacial complex rotated in a clockwise direction around the rotating axis which lay from the most posterior and lowest point connecting nasal crest of maxillary bone and vomer, progressively toward a more posterior, lateral and upward direction, anterior and upper area of pterygomaxillary fissure, base of medial pterygoid plate and laterally to the contact area of zygomatic arch with squamous part of temporal bone. 4. No contraction effect was observed by contraction face-bow when compared to the standard face-bow. 5. In case of expansion face-bow, the areas of maxillary 2nd bicuspid, molars and palate were expanded remarkably.