• Journal of dental hygiene science
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• v.13 no.3
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• pp.339-346
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• 2013

This study conducted questionnaire survey with 268 workers in Ulsan city to examine influencing factors about Oral behavior and Missing teeth of some workers. The collected data were analyzed using SPSS 12.0 program. The analysis results are as follows. 1. Oral health awareness was highest in thirties (p<0.01). For oral health sensitivity, female was higher than male (p<0.01). The lower the age was (p<0.05) and the higher the academic background was, there was statistically significant difference (p<0.01). 2. The lower the age was (p<0.001) and the higher the academic background was, the number of daily tooth brushing was more (p<0.001) and there was statistically significant difference. 3. The more the number of daily tooth brushing was, portion of Missing teeth was low (p<0.01). When oral hygiene devices such as interdental brush, dental floss etc. were used, portion of Missing teeth was low (p<0.01). When dental visit for prevention was made, portion of Missing teeth was low (p<0.05). In case of periodontal disease, portion of Missing teeth was high so that there was statistically significant difference (p<0.01). 4. There was positive relationship according to oral health awareness and oral health sensitivity, oral health status. The oral health status and Missing teeth had a negative effect relationship. Relationship between number of Tooth brushing and Missing teeth showed negative one. In summary, oral health education is needed to increase the motivation of industrial workers to control their basic dental disease.

• Journal of Korean society of Dental Hygiene
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• v.10 no.3
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• pp.441-448
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• 2010

Objectives : This study was conducted in order to investigate the percentage of adolescents who brush their teeth after lunch and its related factors using raw data from the Fourth Korea National Health and Nutrition Examination Survey. Methods : In order to extract adolescents to be subjected to this study, 300 adolescents between the age of 12 to 18 who are currently attending junior and senior high school were chosen out of a total of 4,594 subjects. The results from the health surveys and the oral checkup results from the medical examination conducted on these adolescents were analyzed. Results : 1. The percentage of adolescents who brush their teeth after lunch was 33.9%. 2. The percentage of the adolescents who brush their teeth after lunch differed significantly according to the gender (p<0.001), age (p<0.05), the time of their recent visit to the dentist (p<0.05), and whether they had suffered from permanent tooth caries (p<0.05). 3. The factors which affect whether the adolescents brush their teeth after lunch was their gender, the total number of the times they brush their teeth per day, and their age. Conclusions : Effective oral health education methods should be reinforced in order to increase the percentage of the adolescents who brush their teeth after lunch.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.21 no.2
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• pp.275-285
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• 1991

The clinical and radiographic features of 655 congenitally missing teeth were studied with full mouth periapical radiograms and/or pantomograms from 368 persons visited the Department of Oral Radiology, Infirmary of Dentistry, Kyung Hee University during January 1981 to December 1989. The obtained results were as follows: 1. The prevalence of congenitally missing teeth was revealed to be 8.75% in total examined persons, and there was a higher prevalence in females (9.5%) than in males (8.0%). 2. The most frequently missing teeth were mandibular second premolars (24.6%), followed by mandibular lateral incisors (21.7%), maxillary second premolars (16.2%), and maxillary lateral incisors (11.5%). 3. There was a higher prevalence in the mandible (60.3%) than in the maxilla (39.7%), and no significant differences between right (49.65%) and left (50.35%) side. 4. In number of congenitally missing teeth per person, 54.6% had one missing tooth, and 32.9% had two missing teeth. 5. In persons with one or two congenitally missing teeth, the most frequently missing tooth was mandibular lateral incisor, and the second premolar was the tooth most frequently missing in those persons with more than three congenitally missing teeth.

• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.3
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• pp.239-246
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• 2019

The purpose of this study was to examine dental complications and to evaluate the effects of initial treatment age, treatment modalities, and treatment duration on the disorder after radiation and chemotherapy in pediatric cancer patients. For 93 children with clinical and radiographic data, the number of teeth, the morphology of teeth, the shape of the roots, and development status of the dentition were evaluated. Dental development disorders were found in 61.3% of the children. The mostly found abnormality was root deformity with the prevalence of 31.2%. In children submitted to the therapy before the age of 6, the number of missing teeth (p = 0.029) and microdontia (p = 0.003) were greater compared to the children who started to receive the treatment after the age of 6. The combination of radiation and chemotherapy showed significantly greater incidences of missing teeth (p = 0.030), microdontia (p = 0.046), and root deformity (p = 0.009) when compared with the sole application of chemotherapy. When the children were submitted to anticancer therapy for 18 months or longer duration, greater number of missing teeth (p = 0.032), microdontia (p = 0.011), root deformity (p = 0.025), and total number of teeth affected (p = 0.036) were observed compared with duration less than 18 months. The number of dental abnormalities increased when the children were treated at earlier ages, with combination of radiation and chemotherapy, and for longer period of time.

• Journal of Korean society of Dental Hygiene
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• v.18 no.6
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• pp.921-932
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• 2018

Objectives: The aim of this study was to investigate the number of existing permanent teeth and the denture usage status in elderly adults aged 65 years and above living in metropolitan cities and to confirm the degree of oral health inequality caused by the differences in oral conditions in each metropolitan city using the Lorenz curve and the Gini coefficient. Methods: The raw data for the analysis were obtained from the dataset of the sixth Korea National Health and Nutrition Examination Survey conducted between 2013 and 2015. The subjects included 1,764 people who underwent oral examination and answered questions. The complex samples general linear model was used to analyze the number of existing permanent teeth adjusted for age and monthly household income. The proportion of edentulousness and the denture status was analyzed using complex samples crosstabs. Results: The number of existing permanent teeth in the elderly adults aged 65 years and above was lowest in Ulsan (15.41) and highest in Gwangju (20.44). The proportion of edentulousness was highest in Busan (14.5%) and lowest in Daejeon (4.0%). With regard to the proportion of denture users, Busan had the highest tendency for denture usage (50.4%) and Gwangju had the lowest tendency (34.9) (p=0.172). The Gini's coefficient for the number of existing teeth was lowest in Busan (0.332). Oral health inequality was most severe in metropolitan cities. Conclusions: We found that oral health inequality exists among elderly adults living in the metropolitan cities of Korea using the Lorenz curve and Gini's coefficient.

• Applied Microscopy
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• v.18 no.2
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• pp.132-140
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• 1988

The radulae of six species of bithyniid snails, Bithynia striatula, B. tentaculate, B. siamensis, B. leachi, Gabbia misella and G. australis, were observed by SEM. The radular formula of all the bithyniids studied was 2 : 1 : 1 : 1 : 2. The all teeth were multicuspid and the central teeth had numerous basal denticles. The mesocones of the central and lateral teeth were spade or arrow-head shape. The mesocones of the central teeth and the lateral teeth of B. leachi, G. misella and G. australis were slightly larger than the other cusps in contrast of those of the other species. Number of cusp was varied by the specimen and the species.

• The korean journal of orthodontics
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• v.10 no.1
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• pp.55-64
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• 1980

The purpose of this study was to investigate the interrelationship of the experimental group and control group by analyzing case histories, intraoral radiographs, orthopantomographs, intraoral slide films and dental casts. The data for this study were complied from 654 outpatients of the Department of Orthodontics, Seoul National University Hospital. The following conclusions were obtained. 1. When one or more thins molar teeth were congenitally missing, the incidence of the other congenitally missing teeth was high. 2. The frequency of congenitally missing teeth was comparatively higher in male, maxilla, class II and class III. 3. The congenitally missing srea of the third molar by Angle's classification was not significant. 4. The order of frequency of congenitally missing teeth was the third molar, the second premolar, the lateral incisor, the first premolar, the central incisor, the canine, the first molar, the second molar.

• Proceedings of the KIEE Conference
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• 1991.11a
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• pp.126-129
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• 1991

The effect of each tooth for optimal design of Hybrid permanent magnet step motor is presented on this paper. For this consideration, Hybrid permanent magnet step motor was designed in the first consideration tooth structure on the stator and the rotor and poles structure, as number of teeth on the stator and the rotor and slot depth and pitch of teeth, simulated by AutoLISP. During actual rotating, a chracteristic of Hybrid permanent magnet step motor which designed by AutoLISP program is considered. A chracteristic of Hybrid permanent magnet step motor is considered in change each variable, also. As a result, it was found that characteristic of Hybrid permanent magnet step motor changed in accordance with tooth structure and number of teeth and optimal design is possible by AutoLISP.

• Restorative Dentistry and Endodontics
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• v.6 no.1
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• pp.71-75
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• 1980

The purpose of this study was to determine the close relation between clinical symptom and histopathologic finding in pulp. 20 samples of pulp tissue were collected from badly decayed teeth with considerable pulp vitality. Hemogram was also made with the first drop of bleedieg after total pulp extirpation (10cases) and vital pulpotomy(10cases). Histologic specimen was made routinely with extirpated pulp and stained by H&E and P.A.S. Stains. The results under microsopic examination were as follows; 1. Hemogram obtained from dental pulp with acute inflammation revealed increase of polymorphonuclear leukocyte in number, more lymphocytes and monocytes. 2. Hemogram from pulp with chronic inflammation shown the number of lymphocyte and monocyte was remarkably increased. 3. Histologi specimen obtained from teeth with severe clinical symptome showed polymorphonuclear leukocyte infiltration and the hemogram also showed polymorphonuclear leukocytes. 4. Specimen from teeth with moderate symptom showed lymphocyte infiltration and vessel dilatation underneath decayed area. Erythrocytes were massively accumulated inside of the vessel wall.

• The Journal of the Korean dental association
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• v.12 no.2
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• pp.107-111
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• 1974

In order to collect some necessary data to promote correcting the toothbrushing technic on the Korean public, the author had examined the number of present teeth on which had cervical abrasion and the most basic home dental care in 2,000 Korean male and female adults from 19 to 52 years in the age. Then, the cervical abrasion experience rate and the cervical abrasion experience teeth rate were calculated and evaluated. The obtained results were as follows: 1. Cervical abrasion experience rate was 32.45% 2. Cervical abrasion experience rate was gradually increased by ageing. 3. Cervical abrasion experience rate in male adults was higher than that in female adults. 4. Cervical abrasion experience rate in the lower jaw was higher than that in the upper jaw. 5. Cervical abrasion experience rate of the teeth at the right side was higher than that of the teeth at the left side. 6. Cervical abrasion experience teeth rate was 3.82%. 7. Cervical abrasion experience rate was highest on the first bicuspid, and followed in the sequence of the second bicuspid, canine, first molar, incisors, and 2nd and 3rd molars.