• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.3
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• pp.328-337
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• 2010

The purpose of this study was to research the traumatized primary teeth and investigate following factors: sex, age, cause, place and time(of the year) of injury, elapsed time, area and type of injury, dental treatment and prognosis. The analysis includes total of 1533 traumatized primary teeth from 758 children aging from 6 months to 6 years(mean age: 2.8) from 2003 to 2007. The result follows : 1. The children of age between 1-2 and 2-3 were involved in the largest number of injuries in both sexes with boy/girl ratio of 1.77:1(p<0.001). 2. Fall and collision were the main causes of traumatic dental injury, especially in younger children(p<0.05). Places of injury occurrence varied: home, outdoors, and kindergarten. Warm climate accounts for frequent outdoor injuries in May, September and October(p<0.001). 3. Most of the children visited dental clinic within 24 hours of the injury(77.6%). From March to September, dental trauma occurrences were distributed evenly, except for Winter period(p<0.001). 4. Upper central incisors were the most commonly affected teeth, and the injuries usually involved 1 tooth or 2 teeth. 5. Periodontal tissue injuries dominated and subluxation was the most common type. Lateral luxation, enamel fracture, intrusion and root fracture followed.

• Magazine of the Korean Society of Agricultural Engineers
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• v.17 no.3
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• pp.3860-3871
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• 1975

This experiment was carried out to establish the mechanized methods in stumping and root-clearing, which were the most important works in the reclamation of sloping uplands. The determination of optimum teeth interval of rake blades and its operation methods to reduce the quantity of transported topsoil during the works, are the aims of this investigation. A newly designed rake blade, whose net teeth intervals could be regulated by three stages as 15cm, 25cm, and 35cm, was manufactured to attach to the bulldozer of 13ton. The experiments were carried out at Kilsang-Myon, Kwangwha-Gun, from Aug. 9 to Aug. 23, 1975. For each interval, 36 test plots of 50${\times}$10mn in size, which were regulated under three levels of land slopes of 10, 20, and 30% and two different tree stand density of high or medium values, were randomly chosen and arranged by two-replicated split-split plot design. Each stump classified by its diameter was stumped and cleared by the rake dozer to be related between diameter and stumping time. The results obtained in this experiment can be summarized as follows: 1. Stumping times for the diameters ranging from 6 to 18cm of stumps are almost the same and they are not varied by the difference of teeth intervals of rake dozer. 2. By back-ward stumping method, the number of stumps which can be stumped per hour ranges almost from 100 to 170, showing significant difference with respect to the teeth intervals. The working area is sharply varied with not only the stand density of stumps but the teeth intervals. 3. Optimum stumping distance for each teeth interval of rake dozer to minimize the quantity of transported topsoil are varied with such the rates as it is 15m or 20m for 15cm of teeth interval, but 25m for 25cm or 35cm, respectively. The clearing distance could be chosen almost double as long as the operating distance. 4. The working areas per hour of the simultaneous stumping and clearing methods are no significant difference among the various treatments of working conditions, but they are affected by the operating techniques. However, the influencing factors of the working conditions as classified before and the working directions are ranged from 10 to 15 per cent of total working area, respectively. 5. The residual rates of stumps which are not stumped by the rake dozer in each test plot are generally reduced as the teeth interval gets narrower, but there are no significant difference among them. The mean residual rates average to be about 4% for the simultaneous stumping and clearing method. The back-ward stumping method are recommended to be supervised and directed by more than one man, to show the operator where the stumps are located. 6. The results according to the stumping and clearing methods are summarized as Table IV-2. And the selection of working methods is recommended to follow as shown in Fig. IV-9 with respect to the stand density of the field. 7. Generally speaking, the narrower the teeth interval, the better become the working results, but the more the quantity of transported topsoil is increased. Therefore, it is recommended that the teeth interval should be reduced from the present distance of more than 30cm to 25cm or 15cm, by developing suitable working methods through more field works and experiments.

• The korean journal of orthodontics
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• v.28 no.4 s.69
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• pp.591-600
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• 1998

The purpose of this study was to investigate the root resolution and repair pattern of human teeth according to the force magnitude, direction and duration during the initial leveling and alignment phase. 40gms to 500gms of force applied to the 37 experimental teeth with duration of 3 weeks to 7 months. Then, the experimental teeth were extracted. 13 control teeth were extracted without treatment. The results are as follows: 1. $59.5\%$ of 37 teeth exhibited root resorption. The initial resorption site was visible at the apex within 3 weeks with 100 gms samples, and the initial repair site was visible at the apex within 3 months with 400 gms samples. 2. Number of resorbed teeth increased with the duration of the force. 3. The depth of the resorption increased with the magnitude of the force. 4. The areas of resorbed root corresponded with the loading pattern. 5. The areas of resorbed root were highly correlated with the magnitude of the force. The result of this study suggest that root resorption could occur during the initial leveling and alignment phase, These initial injuries are all small and insignificant. It is the extensive type of apical root resolution that must be regarded as deleterious to the function and stability of the tooth moved. During the initial leveling and alignment phase lighter force of the interrupted type and short treatment period would be favorable with regard to avoidance of root resorption and repair of resorbed root surface.

• Restorative Dentistry and Endodontics
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• v.30 no.2
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• pp.102-111
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• 2005

The purpose of this study was to assess the incidence of flare-ups among patients who received endodontic treatment and to examine the correlation with pre-operative and operative variables. Analysis was in two aspects (a) overall incidence of flare-ups as expressed by a percentage of all patients visits and (b) percentage of flare-ups that occurred as related to various factors suck as patient demo-graphics, diagnosis, and treatment procedures. 1. From the 840 teeth which were examined in this study, the total number of flare-ups was 13. 2. As to gender of patients, there was no significant difference in flare-ups. 3. As to tooth groups, there was no significant difference in flare-ups. 4. In the teeth with pre-operative symptom, there was a statistically significant higher incidence of flare-ups than the teeth without it. 5. In the teeth with apical periodontitis, there was a statistically significant higher incidence of flare-ups. 6. As to pulp and periapical status. non-vital teeth had a higher incidence as compared with vital teeth, irreversible pulpitis. 7. Multi-visit treatment resulted in the higher incidence of flare-ups than one visit treatment. 8. Re-treatment procedures had a statistically significant higher incidence of flare-ups than root canal treatment. In this study, overall percentages of flare-ups was $1.55\%$. It showed a statistically significant higher incidence related to pre-operative symptom, apical periodontitis, and re-treatment. There was no significant difference in flare-ups related to gender, tooth groups, and fistula.

• Journal of Korean society of Dental Hygiene
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• v.10 no.6
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• pp.1083-1093
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• 2010

Objective : The purpose of this study was to examine the relationship of the oral health behavior of oral prophylaxis clients and some residents in a community to their simplified oral environment index. Methods : The subjects in this study were 520 people who had their teeth cleaned in the oral prophylaxis practice lab in the department of dental hygiene at J health college. A survey was conducted from March 23 to June 3, 2010, by way of the self-reported questionnaire. The data materials are analyzed by general characteristics frequency and ratio, the relationship of oral health behavior and sex, age, scaling experience, simplified oral hygiene index $x^{2}$ test analysis. Results : 1. Concerning links between gender and oral health behavior including daily toothbrushing frequency, the largest group of the respondents brushed their teeth three times a day(p<0.05). As to educational experiences on toothbrushing method and the use of oral hygiene supplies, the women had more educational experiences than the men(p<0.05). 2. Regarding connections between age and oral health behavior involving daily toothbrushing frequency, the largest number of the respondents brushed their teeth three times a day in every age group (p <0.001). As for educational experiences on toothbrushing method, those who were in their 50s and up(64.7%) learned about that, and they had more educational experiences with age(p<0.05). As for scaling experiences, the older respondents had their teeth scaled more often (p<0.001). 3. As to relationship between scaling experiences and oral health behavior, there were differences in toothbrushing frequency according to scaling experiences(p <0.05). Regarding educational experiences on toothbrushing method, those who had their teeth cleaned received more toothbrushing education(p<0.001). Concerning smoking, the nonsmokers had more experiences to get their teeth cleaned (p<0.001). 4. As for links between simplified oral environment index and oral health behavior including a time for toothbrushing, the respondents who did toothbrushing after every meal(80.4%) had good simplified oral environment indexes(p<0.05). 5. In regard to relationship between simplified oral environment index and oral health behavior, oral environment index had a positive correlation to the use of oral hygiene supplies( r=0.129**), toothbrushing time(r=0.116**) and educational experiences on toothbrushing method (r=0.099**). Smoking(r=-0.092**) had a negative correlation to that. Conclusion : The above-mentioned findings illustrate that oral health behavior is one of crucial factors to affect oral health status and oral environment care. Therefore oral prophylaxis practice lab visitors should receive education on the right toothbrushing method and the use of oral hygiene supplies to promote their oral health, and an incremental oral health care system that involves regular scaling should be introduced.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.2
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• pp.217-223
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• 2005

The term 'impaction teeth' is used to designate a tooth which remains unerupted in jaw beyond the time at which it should normally be erupted. Most cases of impacted teeth reported in the literature are permanent teeth. The impaction of primary teeth occur rarely whereas impaction of second primary molars is more numerous than all other impactions. Failure of eruption of primary teeth may cause a number of complications, such as interference with development and eruption of successive permanent teeth, malocclusion, cystic change of tooth follicle. The clinican should consider the various treatment option available (a) No treatment and observation, (b) surgical extraction (c) space regainer. Proper treatment plan should be established after thought consideration of impacted tooth and it's relation with successive permanent tooth.

• Journal of Preventive Medicine and Public Health
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• v.5 no.1
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• pp.97-104
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• 1972

For the purpose of ascertaining the status of physical growth and health status of the University Students, an intensive survey was conducted by the authors towards a total of 1,250 (Male 792, Female 458) who passed the written entrance examination at the Kyung Hee University in 1972. The items included the measurements on physical growth, various physical and nutritional indices, status of visual distourbance, dental status and tuberculosis. The findings and results cad be summarized as follows; 1. Physical Growth and Develspment. i) The average of body height by anthropometric was $169.39{\pm}5.05cm$ in male and $157.45{\pm}4.43cm$ in female. ii) The averages of body weight by sex were $59.42{\pm}6.47Kg\;and\;51.81{\pm}5.21Kg$, respectively. iii) The averages of chest-girth were $87.18{\pm}5.30cm\;and\;80.51{\pm}4.53cm$. iv) The averages of sitting-height were $92.21{\pm}2.79cm\;and\;86.28{\pm}2.57cm$. In all cases the male measurements were higher than female. 2. Various ludices about Physical Growth and Development; i) Relative body weights by sex were 35.08 and 32.91, relative chestgirth 51.47 and 51.13, and relative sitting-height 54.43, 54.79, respectively. ii) Rohrer index was 1.222 in males and 1.327 in females, Kaup index 2.071 and 2.089, Verveck index 86.54 and 84.04, and Pelidisi index 91.15 and 93.08, respectively 3. Status of visual distourbance The vision of the students under 0.8 with Landolt's testing chart was 45.4% in left eye and 46.6% in right eye(male: 44.4% and 45.7%, female: 47.2% and 48.0%), while under 0.6 in both visions was 41.0% and 40.5% (male: 40.8% and 40.7%, female: 41.5% and 40.2%), respectively. 4. Dental Status Out of total 19.4% (male 19.2%, female 19.6%) had gingivitis, the female incidence rate of gingivitis was higher than male. Average number of teeth in each subject was 29.6 teeth: male had 29.9 teeth and female had 29.1 teeth. The caries rate was 78.9%(male 75.6%, female 84.5%), the female caries rate was higher than male. Total filing per subject was 35.6% (male 34.0%, female 37.1%), female incidence was higher shan male. The average number of i) Caries per tooth rate was 8.5% in male and 9.2% in female, ii) Missing per tooth rate was 0.3% and 0.2%, iii) Filling per tooth rate was 3.9% and 4.2%. in all cases, the female incidences were higher than the male. The average number of D.M.F. was 3.8 teeth in male and 4.0 teeth in female, female was higher than male. The average rate of D.M.F. was 12.7% in male and 13.7% in female, female was higher than male. 5. Pulmonary infiltration Among the total, 53 students were diagnosed as pulmonary infiltration (tuberculosis), of whom 51 were minimal cases, one were moderately advanced case and one were far advanced case.

• The korean journal of orthodontics
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• v.38 no.2
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• pp.133-143
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• 2008

Objective: This study was performed to identify the characteristics of the MSX1 gene (locus chromosome 4p16) in Korean nonsyndromic cleft lip and palate (CL/P), which is assumed to be a major candidate gene acting as a causal factor in nonsyndromic CL/P and missing teeth. Methods: The 36 individuals (23 males and 13 females) who had visited the department of orthodontics at from 1998 to 2002 and who had nonsyndromic CL/P were included in the study. Using a PCR-based assay, the MSX1 gene was amplified, sequenced, and searched for inferred protein products (Reference: Homo sapiens MSX1, accession number AF426432 and NP_002439). The common single nucleotide polymorph isms were observed. Results: In exon 1, nucleotide "A" of the 253 basepair (bp) region was substituted for "G", and in the 255 bp region, nucleotide "G" was inserted. In exon 2, nucleotide "C" of the 11 bp region was substituted for "A", and "T" or "G" was inserted into the 351 bp region whereas "T" or "A" was inserted into the 352 bp region. In protein analysis, "Thr85Ala" missense mutation was found. The "Thr85Ala" missense mutation in this study is different from those of studies using subjects of other races. Conclusions: The results suggest that there is specific mutation of MSX1 in Korean and it plays an important role in Korean nonsyndromic CL/P. However, any distinct genetic polymorphisms between CL/P with missing teeth in the cleft region and CL/P without missing teeth could not be found.

• The Journal of Korean Academy of Prosthodontics
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• v.62 no.3
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• pp.215-223
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• 2024

The patient in this case presented with a desire to have new dentures due to discomfort with existing ones. At the initial visit, all of teeth were missing except for the mandibular left second molar. As the patient was 65 years old, treatment with dentures and implant-supported prostheses was possible under the national health insurance system, and the patient opted for the mandibular denture using implant. Temporary prostheses were initially provided for patient adaptation, and following successful adaptation period, the treatment progressed. A maxillary complete denture and a mandibular implant-supported denture using two implants in the canines were fabricated. The mandibular denture is a Kennedy Class II removable partial denture which consists of a six-unit porcelain fused to metal fixed dental prostheses supported by the implant in the canines on both sides and left second molar serving as the abutments. Despite severe bone resorption and insufficient abutment teeth, the patient expressed satisfaction with the treatment results. In cases with economic and anatomical constraints affecting the feasibility of complete denture, implant-supported overdenture, and implant-supported fixed dental prostheses, an implant-assisted removable partial denture using implant surveyed crowns proves to be a viable and effective alternative treatment option. Nevertheless, the current dearth of scientifically rigorous studies underscores the necessity for meticulous regular check-up and occlusal assessment.

• Journal of Korean society of Dental Hygiene
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• v.11 no.2
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• pp.197-211
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• 2011

Objectives : OHIP-14 and EQ-5D were used, targeting the residents of farming communities to identify the elements that influence oral cavity's health and quality of life due to health and to identify the importance of oral cavity's health in order to increase health of adults' oral cavity and quality of life via improved health. Methods : This research was conducted from July 17th, 2010 to August 16th, 2010 targeting 600 residents in Goryeong-gun, Gyeongsangbuk-do, aging over 40. The data has been analyzed using Mann-Whitney U test, Kruskal-Wallis test and hierarchical multiple regression through SPSS Win Program 18.0 version. Results : 1. OHIP-14 and EQ-5D based on general characteristics showed lower oral health-related quality of life and health-related quality of life on the following cases: women (p=0.004, p<0.001), older (p<0.001, p<0.001), lower scholastic ability (p<0.001, p<0.001), lower average of average spending money (p<0.001, p<0.001), higher number of chronic disease (p<0.001, p<0.001), less drinking (p=0.012, p=0.008), lower perceived oral health and health status (p<0.001, p<0.001) and non smoking showed only EQ-5D (p<0.001). 2. OHIP-14 and EQ-5D based on oral health behavior showed lower oral health-related quality of life and health-related quality of life on the following cases: no periodic oral check-up (p<0.001, p<0.001), less experience of oral health education (p<0.001, p<0.001), horizontal tooth-brushing method(p<0.001, p<0.001) and lower frequency of tooth-brushing showed only OHIP-14 (p=0.042). OHIP-14 and EQ-5D based on oral health status and subjective oral symptom showed lower oral health-related quality of life and health-related quality of life on following cases: number of existing tooth less than 20 (p<0.001, p<0.001), the number of missing teeth more than 9 (p<0.001, p=0.044), DMFT (Decay, Missing, Filling Teeth) index more than 18 (p<0.001, p<0.001), wears denture (p<0.001, p<0.001), edentulous (p<0.001, p=0.002), have xerostomia (p<0.001, p<0.001) and have chewing discomfort (p<0.001, p<0.001). 3. Factors affecting OHIP-14 were gender, age, perceived oral health status, perceived health status, number of existing teeth, dental status, xerostomia and chewing discomfort, and the of reliability (how well it explains) the final model was 48.7%. EQ-5D showed relevance on gender, age, presence of chronic disease, perceived health status, xerostomia, chewing discomfort and oral health-related quality of life, and the reliability of the final model was 42.9%. Conclusions : In order to improve the quality of life of ruralists, oral health needs to be improved or remained by increasing the rate of possession of the existing teeth and preventing the loss of teeth. In order to do so, improvement of accessibility of dental clinic, change of direction from treatment-centered to prevention-centered health care system, development of oral health education program and various oral health care policies which would vitalize continuous oral health care system are considered to be necessary.