• Imaging Science in Dentistry
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• v.52 no.3
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• pp.267-273
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• 2022

Purpose: The aim of this study was to assess the influence of kilovoltage- peak (kVp) and the metal artifact reduction (MAR) tool on the detection of buccal and lingual peri-implant dehiscence in the presence of titanium-zirconia (Ti-Zr) and zirconia (Zr) implants in cone-beam computed tomography (CBCT) images. Materials and Methods: Twenty implant sites were created in the posterior region of human mandibles, including control sites (without dehiscence) and experimental sites (with dehiscence). Individually, a Ti-Zr or Zr implant was placed in each implant site. CBCT scans were performed using a Picasso Trio device, with variation in the kVp setting (70 or 90 kVp) and whether the MAR tool was used. Three oral radiologists scored the detection of dehiscence using a 5-point scale. The area under the receiver operating characteristic (ROC) curve, sensitivity, and specificity were calculated and compared by multi-way analysis of variance (α=0.05). Results: The kVp, cortical plate involved (buccal or lingual cortices), and MAR did not influence any diagnostic values (P>0.05). The material of the implant did not influence the ROC curve values(P>0.05). In contrast, the sensitivity and specificity were statistically significantly influenced by the implant material (P<0.05) with Zr implants showing higher sensitivity values and lower specificity values than Ti-Zr implants. Conclusion: The detection of peri-implant dehiscence was not influenced by kVp, use of the MAR tool, or the cortical plate. Greater sensitivity and lower specificity were shown for the detection of peri-implant dehiscence in the presence of a Zr implant.

• The korean journal of orthodontics
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• v.48 no.6
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• pp.405-411
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• 2018

Objective: This study was performed to investigate the rate of tooth movement and histological characteristics of extraction sockets those were subjected to corticotomy. Methods: A split-mouth randomized controlled trial experiment was designed. Thirty-two adult, male Wistar rats were divided into 2 groups: healing extraction socket (H) and recent extraction socket (R); these groups were randomly classified into 4 subgroups (0/7/21/60 days). The first maxillary molar was extracted on 1 side and 2 months were allowed for complete bone healing; then, the corresponding molar was extracted on the other side and surgical intervention was performed at the mid-alveolar point of the first maxillary molar. Ten grams of continuous force was applied. The outcomes measured were rate of tooth movement, percentage of periodontal space and histological evaluation. The rate of tooth movement was calculated as the measured distance divided by the duration of molar movement. Histomorphometric evaluations were performed on the second and third maxillary molars. The Wilcoxon signed rank test was used to compare differences between the two groups. Results: There were no significant differences in the rates of tooth movement between H and R groups at any of the 4 time points. The histological appearance and percentage of periodontal space between the R and H groups also demonstrated no significant differences. Conclusions: The rates of orthodontic tooth movement into recent and healed socket sites did not differ between the groups. Histological analysis of tooth movement revealed regional acceleration during every time period.

• Journal of the Korean Society of School Health
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• v.14 no.1
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• pp.107-114
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• 2001

The purpose of this study was to collect basic data for the development of oral health education program of parents and to encourage their actual interest and participation in school oral health program. The authors surveyed parents' awareness and behaviors about the oral health of their children. The subjects in this study were 193 parents of elementary school children in Seoul. The collected data were analyzed, the obtained results were as follows: 1. Thirty-five percent of the parents investigated paid a regular visit to a dental clinic. The most common tooth brushing time among them was after dinner, the second was after breakfast, and this was followed by before bedtime and before breakfast 2. Ninety-four percent of the parents responded that prevention is necessary, 92.2% had a plan to visit a dental clinic to prevent dental caries, and 60.1% experienced receiving pit and fissure sealants. Ninety-seven percent responded that they did check their children's dental caries. 54.9% checked their children's oral status after tooth brushing. The parents who visit a dental clinic on a regular basis were more likely to check their children's teeth after tooth brushing than those who don't(P<0.05). 3. Eighty eight percent of respondents wanted to keep the fluoride mouth rinse program. 4. It is recommended that an oral health education program be developed for parents to visit dental clinics on a regular basis, to educate as to the right tooth brushing time, and to check out their children's oral status after tooth brushing.

• Journal of the Korean Society of School Health
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• v.21 no.1
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• pp.33-41
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• 2008

Purpose : The purpose of this study was to provide the basic data for p lanning oral health education in elementary schol. Methods conducted using a postal, self-administered questionnaire. A questionnaire containing 19 questions about oral health education which was provided by health teachers in elementary schol was used for data colle ction. Total response rate was 64.3% (119 out of 185). Results : Oral health education except one through textbooks was conduc of which taught oral health themselves. The contents of oral he alth education through special clas was mainly focusing on the tothbrushing method, dental caries, and the use of fluo ride. Acording to the grades clasified by the level of education, the order was the 3rd, 1st, and 2nd grade, which mea ns that the lower grades got more training than the h was acquired through the internet (72.2%), health-related organizations or academies (51.5%). Also, materi als for oral health education were obtained from health-related organizations or academies (67%), self-productio n (49.5%). According to the data during the past 5 years it was found that 13.4% health teachers had oral health-related that more traing neded to be conducted from 89.7% health tea chers. The most dificult problem in oral health education were insufficient time (56.7%). Conclusion : For effective oral health education, there needs a developmen t of targeted goal to achieve a systemic oral health education for each grades as wel as a ned for as health teachers to eficiently acquire knowledge and materials for oral health education, it is necessary to hold regular workshops for health teachers, and develop and distribute appro priate educational materials.

• The Journal of Korean Academy of Prosthodontics
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• v.30 no.2
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• pp.286-318
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• 1992

The objective of preventive dentistry is the maintenance of a healthy dentition for the life of a patient. Unfortunately, if an individual has not received the benefit of a comprehensive program of preventive dentistry and has finally reached the edentulous state, as a consequence, he receives a set of complete denture. Dentures are mechanical devices and subject to the principles of mechanics. In some cases, the general health and nutritional status of the patient are felt to be the causative factors. But, the most important thing in residual ridge resorption is felt to be caused by the unequal distribution of functional forces. This study was to analyze mandibular stresses of complete denture occlusion by three dimensional finite element method. The results were as follows ; 1. As deformation and stress distribution of the complete denture of the mandible were concentrated on the upper lingual side of the mandible, alveolar ridge resorption of the mandible occurred from lingual side to labio-buccal side. 2. Analyzing by three dimensional F. E. M., the mandible is a very effective form for tolerating stress and deformation biomechanically. 3. According to the concentration of stress distibution in the upper buccal side of the lower posteriors, buccal shelf area must be a primary stress bearing area in the lower complete denture. 4. Lower complete denture moved horizontally to the balancing side under lateral occlusal force. 5. Bilateral balanced occlusion should be constructed in the complete denture for denture stability, especially in the protrusive movement. 6. Physical property of the denture base material was as important for stress distribution in the denture base as or even more than that in the mandible. 7. Impression technique is very important because of most of stress was concentrated between them due to close contact of the mandible and the denture base.

• Korean Journal of Cleft Lip And Palate
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• v.6 no.2
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• pp.69-89
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• 2003

The purpose of this study was to examine and analyze the basic conditions of dental health of cleft lip and palate patients at early mixed dentition (7-year-old, experimental group A) and early permanent dentition period (12,13-year old, experimental group B) and compare them with those of normal children. The sample was consisted of 25 patients at the age of 7 years, 15 at the age of 12 years and 5 at the age of 13 years. Two trained dentists examined orthopantomographs and clinical photos at the first visit of each patient and distinguished the states by teeth and dental surface and filled them on the prescribed forms. DMF rate, DMF index, FT rate, mean number of permanent teeth with fissure sealants, DMFS index and mean percentage of caries experienced maxillary anterior 6 teeth by tooth type are calculated and compared to those of other studies examined normal children. Oral hygiene of experimental groups is poorer than control groups'. Preventive and treatment rate of experimental groups' are lower than control groups'. More concem and effort are needed about prevention and treatment of dental caries of cleft lip and palate patients.

• 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 dental hygiene science
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• v.18 no.1
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• pp.1-8
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• 2018

Stroke is the second cause of death worldwide, although the survival period is increasing after the occurrence of stroke, severe physical disability is caused with aftereffect. Oral inflammation is not limited to the oral cavity, it can cause malignant changes in other tissues and organs. In previous studies, we confirmed the relationship between tooth loss and stroke due to periodontal inflammation. The purpose of this study was to investigate the relationship between oral health and stroke such as oral hygiene behavior, tooth loss and periodontal disease among Korean adults over 40 years of age. This study was analyzed using the 6th Korea National Health and Nutrition Examination Survey (KNHANES) data. A total of 3,389 adults over 40 years of age were analyzed as final subjects. Socioeconomic statuses and oral health status was analyzed using a complex sample analysis technique. Logistic regression was used to analyze the relationship of oral health and stroke, and 95% confidence intervals were computed using SPSS. When the prevalence of stroke according to oral hygiene behavior was checked, the prevalence of strokes was lower in subjects who had a lot of brushings per day and subjects who used oral hygiene products (p<0.05). The risk of stroke was 2.17 times (95% confidence interval, 1.43~3.28) higher in the group with less than 19 remaining teeth, but it was not statistically significant as a result of adjusting for age and sex, income level, education level, drinking and smoking (p>0.05). Loss of teeth was found to be associated with the risk factor of stroke. Therefore, loss of teeth due to periodontal disease is an additional issue that should be considered as a risk factor for stroke.

• Korean Journal of Health Education and Promotion
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• v.14 no.1
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• pp.63-72
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• 1997

In order to develop the programme for the improvement of dental health among primary school children, epidemiological survey to examine dental caries status was conducted among primary school children in Changwon, Korea. We sampled 2 primary schools and surveyed children from first to sixth grade aged 6-11 years. All samples were 3,206 consisted of 1,715 males and 1,491 females. We assessed caries prevalence on permanent teeth. 1. Children with caries experience on permanent teeth were 15.1% at 1st grade, 48.2% at 2nd grade, 73.8% at 3rd grade, 75.6% at 4th grade, 76.8% at 5th grade, 77.4% at 6th grade. 2. Decayed, Missing and Filled teeth were 0.31 at 1st grade, 1.16 at 2nd grade, 2.12 at 3rd grade, 2.38 at 4th grade, 2.50 at 5th grade, 2.69 at 6th grade. 3. Decayed teeth among Decayed, Missing and Filled teeth were totally 63.4%. Filled teeth among Decayed, Missing and Filled teeth were totally 36.6%. 4. Community dental health programmmes including water fluoridation, fluoride mouth rinsing, use of fluoride-containing toothpastes and fissure sealants should be developed to prevent dental caries among school children. 5. School incremental dental care programme should be also developed to prevent and treat children's dental caries by use of dentists and oral hygienists.

• Journal of Korean society of Dental Hygiene
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• v.16 no.2
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• pp.295-301
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• 2016

Objectives: The purpose of the study was to investigate the association between denture wearing and dementia using a Mini-Mental State Examination (MMSE-K) in the community dwelling elderly. Methods: The study subjects were 184 community dwelling elderly using Korean version of mini-mental state examination(MMSE-K). The variables included the general characteristics of the subjects, denture earing, number of mastication tooth, subjective mastication ability, and MMSE(dementia). Denture wearing was divided into two groups of the natural dentition including the fixed prosthesis and removable denture including the complete and/or partial denture. The data were analyzed by ${\chi}^2$ test, t-test, and binary logistic regression using SPSS version 22.0 program. Logistic regression was used to analyze the association of MMSE-K score and denture wearing, and 95% confidence interval was calculated. The subjective mastication ability was measured by Likert 5 points scale. Dementia was measured by MMSE-K. Results: There was a significant association between MMSE-K score and denture wearing. The odds ratio(OR) of denture waering was 6.01(95% CI: 2.824-12.784). After adjusting the age, gender, residence and education, OR was 5.53(95% CI: 2.364-12.935). Conclusions: This study showed a significant association between MMSE-K score and denture wearing in the Korean elderly.