• Korean Journal of Cleft Lip And Palate
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• v.4 no.2
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• pp.19-27
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• 2001

This study was performed to determine the prevalence of hypodontia and hyperdontia of permanent teeth among Korean schoolchildren, and to compare differences in the prevalence between Korea, other country, and other ethnic groups. The sample consisted of 346 girls aged 6.9～0.3 yr and 375 boys aged 6.8～0.4 yr on whom a panoramic radiograph was taken at Yeonchun-Gun community in Korea. The prevalence of congenitally missing teeth (third molars excluded) was 6.7% in boys and somewhat higher, 9.5% in girls, and 8.0% for both sexes combined. On the average, number of missing teeth per affected child was 1.9 teeth. The most commonly congenitally missing teeth were the mandibular second premolar (32.7%), followed by the mandibular incisor (28.7%), the maxillary second premolar (16.7%), and the maxillary lateral incisors (10.2%). The prevalence of supernumerary teeth was 2.1 % in boys, 1.4% in girls, and 1.8% for both sexes combined. The most common supernumerary teeth were the mesiodens (76.9%), followed by the supernumerary premolar (23.1 %). The affected male-female ratio was 1.6: 1.0. The prevalence of congenital missing teeth in this study was similar to in studies of Japanese, Danish, American and German. The frequency of hyperdontia was lower in this study than in studies of Chinese children, Japanese and American.

• Journal of dental hygiene science
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• v.17 no.5
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• pp.447-453
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• 2017

The purpose of this study was to analyze the relationship between objective oral health status determined by dentists, self-perceived subjective oral health status, and oral health related quality of life (OHRQoL) in the elderly. The related factors affecting OHRQoL in the elderly were also surveyed. Four hundred and thirty elderly individuals who visited the three public health centers and four dental clinics in Busan were selected by convenience sampling. Twelve dental hygienists investigated the subjective oral health status and OHRQoL using the 14-item Oral Health Impact Profile (OHIP-14) and twentyone dentists examined the objective oral health status, including healthy remaining teeth, treated remaining teeth, functional remaining teeth, missing teeth, and non-treated missing teeth. Data were analyzed using SPSS ver. 12.0. OHRQoL was higher when oral and periodontal status was perceived as healthy, when there was no toothache, no interference in mastication, and when study subjects had the ability of food softening. It was also higher when study subjects had ${\geq}20$ remaining teeth and <9 missing teeth, and were wearing denture. The related factors affecting OHRQoL of the elderly were the type of medical insurance, toothache, ability of food softening, perception of periodontal status, and the number of healthy remaining teeth. There was a significant relationship between the subjective-objective oral health status and OHRQoL in the elderly. A continuous oral health care system aimed at retaining ${\geq}20$ healthy remaining teeth is needed to improve oral health and OHRQoL for the elderly, especially for the elderly receiving medical aid.

• Journal of dental hygiene science
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• v.17 no.5
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• pp.454-461
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• 2017

The purpose of this study was to confirm the relevance of dental health capacity and pulmonary function status. The subjects of this study were adults aged 40 years and older, who participated in pulmonary function and oral examinations. The data used for this study were raw data from the sixth Korea National Health and Nutrition Examination Survey (2013~2015). Statistical analysis was performed by analysis of complex sample survey data. The results were as follows: First, restrictive and obstructive patterns were more prevalent among males than females. They were even worse in older subjects. Approximately 67% of smokers had obstructive pattern. Second, there was a relevance between dental health capacity and pulmonary function status. The functioning teeth index, number of present teeth, and number of sound teeth (ST), which are indicators of dental health, declined with decreased pulmonary function. The number of missing teeth (MT) increased as the pulmonary function deteriorated (p<0.05). Third, the relevance between dental health capacity and pulmonary function status after stratifying the life-long smoking experience was statistically significant in the tissue health (T-health) index and ST among non-smokers. The relevance between dental health capacity and pulmonary function status after stratifying the life-long smoking experience was statistically significant (p<0.05) for the T-health index, ST, and MT among smokers. However, there was no relevance between dental health capacity and pulmonary function status after stratifying the life-long smoking experience and adjusting confounding variables. In conclusion, there was a relevance between dental health capacity and pulmonary function status after confounding variables were adjusted. However, there was no relevance between dental health capacity and pulmonary function status after stratifying the life-long smoking experience and adjusting confounding variables.

• Journal of Digital Convergence
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• v.14 no.2
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• pp.279-286
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• 2016

Recently, with the population growth of elderly people, concerns about oral health related to the quality of life of the elderly are increasing. The purpose of this study is to assess the association between the elderly women divided into dementia, suspected dementia, healthy groups and the remaining teeth of them. Total 177 elderly women of over 60 years old, visiting on senior center in some community dwelling, were assessed for oral condition and their cognitive function with MMSE score. All the collected data were analyzed by chi-square test, t-test, and multiful logistic regression using SPSS. Multiful logistic regression was used to analyze the relationship of dementia according to MMSE score and remaining teeth, and 95% confidence intervals were computed. Odds ratio(OR) of the number of remaining teeth 0-10 was 3.43 (95% confidence interval: 1.382-8.997). This study showed significant difference and the relationship between dementia according to MMSE score and the number of remaining teeth of the elderly women.

• Journal of Digital Convergence
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• v.14 no.7
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• pp.225-232
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• 2016

This paper aimed to study on the relevance of mental health and oral health. The subjects were recruited total 3,261 elderly of over 40 years old, using the Sixth Korea National Health and Nutrition Examination Survey(KNHANES). All the collected data were analyzed by chi-square test, t-test, and logistic regression using SPSS 23.0 version. Logistic regression was used to analyze the relationship of sleeping time or stress and the number of remaining teeth, and 95% confidence intervals were computed. Sleeping time odds ratio(OR) of the number of remaining teeth was 1.52 (95% confidence interval: 1.074-2.135) and Stress odds ratio(OR) was 2.39 (95% confidence interval: 1.855-3.090), but there is no statistically significant difference after adjusted age, gender and other variables.

• Journal of the korean Society of Automotive Engineers
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• v.3 no.2
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• pp.27-33
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• 1981

In the paper, it was attempted to verify how the strength around fillet area of shifted gear would be affected by variables such as number of teeth, shifted value, and diametral pitch. Thereafter, the Lewis' tooth factor of the shifted gear was computed in terms of previously mentioned variables in order to observe the characteristics of stress change related from tooth factor and tooth number with the parameter of shifted values and diametral pitches. From the results of quasi-theoretical values by Finite Element Method(F.E.M.)and experimental values through the photo-elastic tests, the followings were identified. The more the number of gear teeth increased, the more the profile of the tooth became close to that of rack, and accordingly the stresses in the fillet area decreased significantly in certain range. Furthermore, as the shifted value and pressure angle increase the stresses tend decrease. Moreover, the stresses analyzed by F.E.M. in the filled area became around 1.22 times larger than the stresses computed by Lewis' form factor, and this is supposed as on influence of the stress concentration in fillet area.

• Journal of Korean society of Dental Hygiene
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• v.19 no.5
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• pp.715-729
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• 2019

Objectives: This study aimed to validate the moderating effect of oral health on the relationship between perceived health status and health-related quality of life in the elderly and to use this information as primary data to suggest oral health policies for the aged society. Methods: This study included 3,707 subjects aged over 65 years who answered all the variables used in the study model and completed the health questionnaire and screening survey based on the sixth Korea National Health and Nutrition Examination Survey. Baron & Kenny's linear regression analysis using SPSS 22.0 and SPSS Macro Version 3.1 programs was performed to confirm the moderating effect of the number of remaining natural teeth, chewing difficulty, and cardiovascular disease on the relationship between perceived health status and healthrelated quality of life in the elderly. Results: The number of remaining natural teeth, chewing difficulties, and cardiovascular diseases affected the perceived health status of the elderly. As the number of remaining natural teeth increased, the effect of perceived health status on the quality of life in the elderly was buffered. The effect of perceived health status on the quality of life increased with chewing difficulties and the number of cardiovascular diseases. In particular, it was confirmed that chewing difficulties, rather than the number of cardiovascular diseases. had a greater effect on the quality of life in the elderly. Conclusions: Oral health policies and projects are required to ensure oral rehabilitation with dentures and implants and restore chewing function to improve the quality of life of the elderly in Korea.

• Journal of Korean society of Dental Hygiene
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• v.7 no.1
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• pp.1-13
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• 2007

In Korea, respect for the aged and filial devotion is treated as basic ethics for human life, and family takes care of the aged person mainly. Nowadays, family support on the aged person is prioritized than the others. However, number of aged person is growing, and family, which is used to protect the aged, becomes nuclear through industrialization. In addition, social advancement of female induces weakened supporting function of family, and all these issues generate the problem of protection for the aged as significant social problems. Author conducted oral inspection and questionnaire for the aged in some welfare facilities in Gyeongnam location from December 2005 to February 2006 to improve quality of life and oral hygiene of the aged. Through gathered data, the actual condition of oral hygiene management on the aged person in welfare facility was evaluated as fundamental data for project development on oral hygiene of aged person. Through the analysis of inspected data, the following conclusions are derived. 1. Management status of oral hygiene is mostly not good, and toothbrushing per day is 'one time' for the most cases. 2. In free-of-charge facility, monthly allowance is 'under 50 thousand won' for the most cases. 3. Time for visiting oral treatment facility is on 'when toothache is occurred' for the most cases. For treatment content, 'prosthetic dentistry' takes 36.8% in charged facility, and 'tooth extraction' is 27.0% for free-of-charge facility. 4. Average DMFT index of the aged in charged facility is 16.81, and free-of-charge facility is 21.71. 5. Average number of functional teeth in charged facility is 15.22, and free-of-charge facility shows 7.29. 6. Average number of remained teeth in charged facility is 15.71, and the umbe in free-of-charge facility is 9.04. 7. Average number of extractable teeth in charged facility is 0.48, and for free-of-charge facility, the number goes up to 1.70.

• Journal of Korean society of Dental Hygiene
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• v.20 no.5
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• pp.743-752
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• 2020

Objectives: The objectives of this study were to investigate the distribution and level of periodontopathic bacteria with the general characteristics and oral health condition of the elderly. Methods: A total of 335 elderly individuals aged 65 years or older who lived in Ganghwa-gun, Incheon, were included in the study. Oral examination, investigation through a questionnaire, and collection of saliva were carried out. The collected saliva was analyzed for the distribution and levels of bacteria (red and orange complex bacteria) by real-time polymerase chain reaction. Statistical analyses were performed using chi-square test, t-test, one-way analysis of variance, and Pearson's correlation coefficient with SAS statistical software version 9.4. Results: Among the general characteristics, there were significant differences in the distribution of Porphyromonas gingivalis, Treponema denticola, and Parvimonas micra depending on sex, age, and dental visits (p<0.05). The number of remaining teeth and denture use were related to the distribution of periodontopathic bacteria, except T. denticola (p<0.05). Additionally, periodontitis was related to the distribution of P. gingivalis (p<0.05). As the number of remaining teeth increased, the copy number of red and orange complex bacteria also increased (p<0.05). Those individuals who did not use dentures and had periodontal disease had more periodontopathic bacteria (p<0.05). Conclusions: The distribution and copy number of periodontopathic bacteria in the elderly were more related to oral health condition than to general characteristics. In particular, the distribution and copy number of periodontopathic bacteria were higher in subjects with multiple remaining teeth, no dentures, and periodontal disease.

• The Journal of Korean Academy of Prosthodontics
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• v.57 no.1
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• pp.42-48
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• 2019

In the case of a patient with a small number of unilateral remaining teeth in the mandible, a restoration with conventional removable partial denture cannot provide sufficient retention and resistance. A harmful stress from the poor stability of denture on remaining teeth occurs due to alveolar bone resorption in edentulous area. Although implant fixed prosthesis can provide multiple benefits over conventional removable partial denture, there are limitations come from anatomic structures and costs. In this case, an implant-assisted removable partial denture (IARPD) with a couple of implants placed in strategic positions can be a treatment modality. The objective of this article is to present a case report of two patients showed satisfactory clinical outcomes during three-year follow-up period describing the fabrication and advantages of removable partial denture assisted by teeth and implants (IARPD) for a patient with a small number of unilateral remaining teeth in mandible using Locator as an implant attachment.