• The Journal of Advanced Prosthodontics
• /
• v.13 no.1
• /
• pp.65-70
• /
• 2021

Purpose. Implant mechanical complications, including screw loosening, can influence dental implant success. It has been shown that torque values are affected by contamination occurred in implant-abutment (I/A) interface. This study aimed to examine the effects of blood, saliva, fluoride and chlorhexidine contamination on reverse torque values (RTVs) of abutment screws in oral conditions. Materials and Methods. 50 fixtures were mounted into the stainless-steel holders and divided into five groups (n = 10). Except control group (NC), fixture screw holes in other groups were contaminated with chlorhexidine (CG), saliva (SG), blood (BG), or fluoride (FG). Abutment screws were tightened with a digital torque meter. I/A assemblies were subjected to thermocycling and cyclic loading. The mean RTVs were recorded and data were analyzed with one-way ANOVA and Tukey test. Results. Except for specimens in SG (20.56 ± 1.33), other specimens in BG (21.11 ± 1.54), CG (22.89 ± 1.1) and FG (24.00 ± 1.12) displayed significantly higher RTVs compared to NC (19.00 ± 1.87). The highest RTVs were detected in CG and FG. Conclusion. The obtained data robustly suggest that RTVs were significantly affected by fluid contaminations. Specimens in FG and CG displayed the highest RTVs. Therefore, clinicians should have enough knowledge about probable contaminations in I/A interface in order to manage them during clinical procedure and to inform patients about using oral care products.

• Imaging Science in Dentistry
• /
• v.31 no.1
• /
• pp.1-7
• /
• 2001

Purpose : To evaluate the usefulness of the reconstructed 3-dimensional image on the personal computer in comparison with that of the CT workstation by quantitative comparison and analysis. Materials and Methods : The spiral CT data obtained from 27 persons were transferred from the CT workstation to a personal computer, and they were reconstructed as 3-dimensional image on the personal computer using V-works 2.0/sup TM/. One observer obtained the 14 measurements on the reconstructed 3-dimensional image on both the CT workstation and the personal computer. Paired Nest was used to evaluate the intraobserver difference and the mean value of the each measurement on the CT workstation and the personal computer. Pearson correlation analysis and % incongruence were also performed. Results: I-Gn, N-Gn, N-A, N-Ns, B-A, and G-Op did not show any statistically significant difference (p>0.05), B-O, B-N, Eu-Eu, Zy-Zy, Biw, D-D, Orbrd R, and L had statistically significant difference (p<0.05), but the mean values of the differences of all measurements were below 2 mm, except for D-D. The value of correlation coefficient y was greater than 0.95 at I-Gn, N-Gn, N-A, N-Ns, B-A, B-N, G-Op, Eu-Eu, Zy-Zy, and Biw, and it was 0.75 at B-O, 0.78 at D-D, and 0.82 at both Orbrd Rand L. The % incongruence was below 4% at I-Gn, N-Gn, N-A, N-Ns, B-A, B-N, G-Op, Eu-Eu, Zy-Zy, and Biw, and 7.18%, 10.78%, 4.97%, 5.89% at B-O, D-D, Orbrd Rand L respectively. Conclusion : It can be considered that the utilization of the personal computer has great usefulness in reconstruction of the 3-dimensional image when it comes to the economics, accessibility and convenience, except for thin bones and the landmarks which are difficult to be located.

• Journal of Veterinary Clinics
• /
• v.5 no.1
• /
• pp.23-30
• /
• 1988

A total of 127 foremilk samples from dairy farms in Chonnam district was examined for the subclinical mastitis eve. six months, using a method of the N-acetyl-${\beta}$ -D-glucosaminidase (NAGase) test in relation to the California mastitis test(CMT) and the somatic tell count(SCC) and the compatibility and efficiency rating between the NAGase test and the other screening test were conducted. Fifteen subclinically mastitic cows were treated with a single oral dose of 7.5mg/kg of levamisole hydrochloride. The results are summarized as follows. 1. A linear relationship was found among the NAGase level, the CMT score and the SCC level, and it was found that NAGase activity measurements were comparable with other screening tests for diagnosing cows with mastitis. 2. Compatibilites between the NAGase and the CMT were 96.1%, and that of the NAGase and SCC were 93.7%. On the other hand, relative efficiency ratings of Postle's equation between the NAGase and CMT were 89.4%, and that of the NAGase and SCC were 84.1%. 3. Considering the result of CMT, SCC and NAGase level after treatment with levamisole hydrochloride it seemed to be of special value in the treatment of bovine subclinical mastitis.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
• /
• v.12 no.1
• /
• pp.27-33
• /
• 1982

The purpose of this study is to obtain some informations for the differential diagnosis of ameloblastoma from dentigerous cyst by analysis of the radiographic findings of these lesions. The author studied age and sex distribution, the site of the lesion, tooth behavior and several radiographic features of ameloblastoma and dentigerous cyst. The material consisted of 65 patients of ameloblastoma and 37 patients of dentigerous cyst. The results were obtained as followings. 1) The incidence was highest in 2nd decade (29.2%) and total 65 cases consists of 35 males (53.8%) and 30 females (46.2%) in ameloblastoma. 62 cases were found in lower jaw (95.4%) and the highest site of occurence of ameloblastoma was mandibular molar. region 27 cases. (41.5%) 2) In 65 cases of amelobl!!stoma, 18 cases were seen in association with tooth and 15 cases (83.2%) out of those were associated with mandibular molar teeth. Mandibular molar were most frequently involved in dentigerous cyst (11/31 cases, 29.7%). 3) (a) 23 cases (35.3%) of tooth resorption were found in ameloblastoma and 11 cases (29.7%) of tooth resorption were found in dentigerous cyst. (b) 15 cases (23.1%) of tooth migration were found in ameloblastoma and 10 cases (27.0%) of tooth migration were found in dentigerous cyst. 4) Several radiographic features. (a) Monolocular type ameloblastoma were seen in 23 cases (35.4) and multilocular type of ameloblastoma were seen in 42 cases (64.6%). Monolocular type of dentigerous cyst were seen in 33 cases (89.2%) and multilocular type was seen in 4 cases. (b) Monolocular type ameloblastoma showed 20 cases (87.0%) of scalloped border but 32 cases (97.0%) of dentigerous cyst showed smooth border. (c) 34 cases (81.0%) of ameloblastoma showed honey-comb appearance, soap-bubble appearance or mixed appearance. but all 4 cases of dentigerous cyst showed multicystic appearance. (d) 12 cases (52.2%) of monolocular type ameloblastoma showed slightly increased radiopacity in surrounding bone, and 22 cases (66.7%) of monolocular type dentigerous cyst showed sharp osteosclerotic border. 27 cases (64.3%) of multilocular type ameloblastoma and 3 cases (75.0%) of multilocular type dentigerous cyst showed no changes in surrounding bone.

• Journal of dental hygiene science
• /
• v.12 no.4
• /
• pp.348-358
• /
• 2012

This study aims to prepare the basic data of the teeth color by measuring analyze mode using the color of the maxillary anterior teeth (maxillary central incisor, lateral incisor, canine) of the college students in their twenties as the dental colorimeter. The maxillary anterior teeth of the subjects of study as 467 students (male 89, female 378) were measured from 14 November to 2 December, 2011, so the color of total 1,401 teeth was examined, and oral health and eating habit attributes were researched. The survey results were as follows. 1. The color of maxillary anterior teeth was changed from maxillary central incisor to maxillary canine, brightness ($L^*$) was decreased $76.79{\pm}4.86$ to $69.72{\pm}4.62$, red chroma ($a^*$) was increased $2.02{\pm}2.00$ to $4.10{\pm}2.60$, yellow chroma ($b^*$) was increased $15.51{\pm}3.42$ to $20.10{\pm}3.46$. 2. Brightness ($L^*$) was different according to sex (p< 0.001), major (p<0.001), grade (p<0.001), smoking (p<0.001), oral health education (p<0.01), daily brushing frequency (p<0.001), brushing method (p<0.05), oral hygiene devices (p<0.001), and red chroma ($a^*$) to major (p<0.001), daily brushing frequency (p<0.05), brushing time after meals (p<0.01), oral hygiene devices (p<0.01), and yellow chroma ($b^*$) to brushing time after meals (p<0.01), subjective tooth color (p<0.001). 3. Brightness ($L^*$) of eating habit attributes was different according to coke, candy ($R^2=0.053$, p<0.05). In conclusion, this study demonstrates that the color of maxillary anterior teeth has differences in brightness ($L^*$), red chroma ($a^*$), yellow chroma ($b^*$) from each tooth, also these showed various tendency according to the oral health and eating habit attributes.

• Journal of Technologic Dentistry
• /
• v.30 no.2
• /
• pp.121-133
• /
• 2008

The purpose of this study was to evaluate the role of socioeconomic factors and health behaviors on the prevalence of oral diseases(dental caries and periodontal disease) among Korean adults. Data from the 2005 National Health and Nutrition Examination Survey was analyzed for adults aged over 19 years (n=25,215). Oral disease was defined as disease diagnosed by a dentist for the previous 12 months. Chi-square test and logistic regression analysis were used to conduct statistical analysis. The population without dental caries and periodontal diseases were used as the reference category for all analysis. The overall prevalence of annual dentist-diagnosed dental caries and periodontal diseases were 23.5% and 10.6% respectively. The relative risk of developing dental caries for graduates of middle school and lower were 1.53 times (95% CI: 1.24-1.89) more likely to develop dental caries comparing to college graduates. Low income earners were 1.23 times(95% CI: 1.01-1.49) more likely to develop dental caries than high income earners. Persons covered by national medical insurance were 1.45 times(95% CI: 1.08-1.95) more likely to develop dental caries comparing to persons covered by employee medical insurance. Compared with persons not eating snacks, the risk of developing caries in persons eating snacks once a day was 1.16(95% CI: 1.01-1.32), while those who snacked twice or more a day were 1.19(95% CI: 1.01-1.41). The relative risk of developing periodontal disease was 3.71(95% CI: 2.38-5.80) higher in older individuals than younger. In terms of education level, middle school graduates and lower were 1.54 times more likely to develop periodontal disease than college graduates. Low income earners were 1.47 times more likely to develop periodontal diseases than high income earners. Using data from a large, nationally representative sample of Korean populations, we support the hypothesis that the prevalence of oral diseases is related with socioeconomic factors and health behaviors. More intensive intervention efforts to reduce the prevalence of dental diseases are warranted in Korea.

• Journal of Periodontal and Implant Science
• /
• v.25 no.1
• /
• pp.89-98
• /
• 1995

P. intermedia are considered an important pathogen in adult periodontitis, rapidly progressing periodontitis, refractory periodontitis, pregnancy gingivitis, acute necrotizing ulcerative gingivitis, pubertal gingivitis. So far 2 DNA homology groups and 3 serotypes of P. intermedia have been reported but there is no data available as yet regarding genetic diversity for the species P. intermedia. The purpose of this study is to investigate, using bacterial DNA restriction endonuclease analysis, genetic diversity between individual strains of P. intermedia which are indistinguishable by serotyping and biotyping, occurrence of an intrafamilial transmission and genetic heterogeneity between P. intermedia strains isolated within a patient and within the same serotypes. The families who have had no systemic disease, no experience of periodontal treatment for the previous 1 year and no experience of antibiotics for the previous 6 months were selected and subgingival plaque was collected at 4 sites in each person and incubated in the anaerobic chamber. P. intermedia were identified by colony shape, gram stain, biochemical test, SK-I03(Sunstar Inc.) test and IIF using monoclonal antibody was perfomed for the determination of serotypes. P. intermedia strains were grown in BHI broth and whole genomic DNA was extracted and digested by restriction endonuclease. The resulting DNA fragments were separated by agarose gel electrophoresis, stained and photographed under UV. As the results of this study, intrafamilial vertial transmissions could be assessed in 2 families and horizintal transmissions in another 2 families. There were different DNA digest patterns within a patient, so P. intermedia showed that individuals could be colonized by multiple clonal types at anyone time. And different serotypes could be found within a patient and in the same serotype within a patient, obvius genetic heterogeneity could not be assessed. But in the same serotype in different famies, there were differences in the DNA digest patterns.

• Journal of Microbiology and Biotechnology
• /
• v.24 no.4
• /
• pp.556-562
• /
• 2014

The occurrence of human norovirus (NoV) genogroup I (GI) and genogroup II (GII) strains was investigated in Korea. Between 2007 and 2010, 265 samples were collected from 89 Korean water source locations. NoV GI was detected in 4.5% and NoV GII in 1.5%. Samples collected in winter had the highest occurrence; 9.4% for NoV GI and 6.3% for NoV GII. NoV GI detection was highest in groundwater, with the next highest in river water and the lowest in lake water (5.9%, 5.4%, and 1.6%, respectively), and NoV GII was found only in river water. When three representative Korean basin systems (Han (H)-, Geum/Seom (G/S)-, and Nakdong (N)-river basins) were compared, both NoV genogroups were high in the G/S-, but absent in the H- river basin. The most prevalent genotypes within the GI and GII groups were GI.5 and GII.4, respectively. The NoVs found in surface water were identical to those found in patients and those found in groundwater. The NoVs appeared to be transmitted from the patient to the surface water, and then to the groundwater, suggesting a fecal-oral route of transmission. This is the first nationwide surveillance of NoV in major Korean water sources.

• Bulletin of the Korean Chemical Society
• /
• v.30 no.7
• /
• pp.1489-1496
• /
• 2009

This study was done for the determination and excretion profile of adrenosterone and its metabolites in human urine using both liquid chromatography with atmospheric pressure chemical ionization mass spectrometry and gas chromatography with mass spectrometry. Adrenosterone and its two metabolites were detected in human urine after administration a healthy volunteer with 75 mg of adrenosterone. We found that adrenosterone-M1 ($C_{19}H_{26}O_3$) was a reduction and adrenosterone-M2 ($C_{19}H_{26}O_4$) was a hydroxylation at C-ring, which did not know the exact position of the C-ring. The adrenosterone parent was detected by GC/TOF-MS, but not detected by LC/APCI/MS because of low intensity. Adrenosterone and its two metabolites were excreted as their glucuronided fractions. The recovery of this method ranged from 100.7 to 118.4% and the reproducibility and accuracy test were 85.5 to 112.0% and 1.1 to 8.4%, respectively. The excretion studies showed that adrenosterone and its metabolites were detectable in human urine during a 48 h period after oral administration, with maximum level of excretion at 4.1 h. The glucuro-/sulfaconjugated ratio of adrenosterone, M1 and M2 was 0.73 ${\pm}$ 0.03, 0.96 ${\pm}$ 0.06 and 0.89 ${\pm}$ 0.03 (n = 6), respectively. The amounts of adrenosterone excreted in urine were 14.75 ng for 48 h. Also, the maximum level of androsterone and 11$\beta$-hydroxy androsterone, which were endogenous steroids, were reached 4.1 h after the oral administration of adrenosterone.

• Journal of dental hygiene science
• /
• v.12 no.3
• /
• pp.235-243
• /
• 2012

The purpose of this study was to examine the oral symptoms, self-rated systemic health state and oral health status of industrial workers in a bid to provide some information on oral health education geared toward industrial workers. The subjects in this study were 294 workers who got a medical checkup in Korea Industrial Health Association in North Gyeongsang Province. Those who felt less inconveniences in the oral cavity led a better quality of life related to oral health in every area except physical handicaps (p<.001, p<.01). The men's OHIP-14 was higher than the women's, and the younger workers led a better quality of life related to oral health in the area of social separation(p<.01), and the married ones did in the area of physical handicaps, mental disorder and social separation(p<.05). And the workers whose household income was larger lived a better quality of life related to oral health in the areas of Psychological discomfort, physical handicaps, mental disorder, social disorder and social separation(p<.05). Those who found themselves to be generally in good health(p<.001, p<.05) and whose subjective oral health state was led a better quality of life in every area(p<.001, p<.05). The findings of the study showed that there were differences in the quality of life according to awareness of oral symptoms, general health status and oral health state.