• The Journal of Korean Academy of Prosthodontics
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• v.51 no.4
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• pp.276-283
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• 2013

Purpose: The purpose of this study was to investigate the fit and screw joint stability between Ready-made abutment and CAD-CAM custom-made abutment. Materials and methods: Osstem implant system was used. Ready-made abutment (Transfer abutment, Osstem Implant Co. Ltd, Busan, Korea), CAD-CAM custom-made abutment (CustomFit abutment, Osstem Implant Co. Ltd, Busan, Korea) and domestically manufactured CAD-CAM custom-made abutment (Myplant, Raphabio Co., Seoul, Korea) were fabricated five each and screws were provided by each company. Fixture and abutments were tightening with 30Ncm according to the manufacturer's instruction and then preloding reverse torque values were measured 3 times repeatedly. Kruskal-Wallis test was used for statistical analysis of the preloading reverse torque values (${\alpha}=.05$). After specimens were embedded into epoxy resin, wet cutting and polishing was performed and FE-SEM imaging was performed, on the contact interface. Results: The pre-loading reverse torque values were $26.0{\pm}0.30Ncm$ (ready-made abutment; Transfer abutment) and $26.3{\pm}0.32Ncm$ (CAD-CAM custom-made abutment; CustomFit abutment) and $24.7{\pm}0.67Ncm$ (CAD-CAM custom-made abutment; Myplant). The domestically manufactured CAD-CAM custom-made abutment (Myplant abutment) presented lower pre-loading reverse torque value with statistically significant difference than that of the ready-made abutment (Transfer abutment) and CAD-CAM custom-made abutment (CustomFit abutment) manufactured from the same company (P=.027) and showed marginal gap in the fixture-abutment interface. Conclusion: Within the limitation of the present in-vitro study, in domestically manufactured CAD-CAM custom-made abutment (Myplant abutment) showed lower screw joint stability and fitness between fixture and abutment.

• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.293-301
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• 2013

This study was carried out to investigate the pesticide residue pattern among different leafy vegetables applied with foliar spraying under greenhouse and to check extrapolating from some residue trial data to other minor crops. Leafy vegetables used in this study were: Mustard greens (Brassica juncea L.), Kale (Brassica oleracea L.), Dacheongchae (a kind of pak-choi (Brassica rapa subsp. chinensis L.)), Leaf broccoli (Brassica oleracea var alboglabra), Perilla leaf (Perilla frutescens (L.) Britton var. Frutescens), Leaf lettuce (Lactuca sativa L.), Swiss chard (Beta vulgaris L. subsp. vulgaris) and Red leaf chicory (Cichorium intybus L. var. foliosum Hegi). These are cultivated all year under indoor or outdoor and cut the leaf from plant continuously during harvest time. The amounts of pesticide deposit in/on the continuous harvesting leafy vegetables were affected by the ratios of leaf area to weight. Ratio of perilla leaf was the largest among crops as 58 $cm^2/g$. The residue levels of 7 pesticides in/on perilla leaf were the highest than those of other crops through the statistical analysis from zero day to fifth day after last application. The representative crop in 8 crops was perilla leaf selected based on the amounts of daily consumption and the high residues. This study suggest that the continuous harvesting leafy greens should be separated from the one time harvesting leafy vegetables for the pesticide recommendations because of different harvesting habits and pre-harvest intervals.

• Journal of The Korean Dental Society of Anesthesiology
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• v.14 no.1
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• pp.17-27
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• 2014

Background: Various medical emergency situations can occur during dental practices. Cardiac arrest is known to comprise approximately 1% of emergency situation. Thus, it is necessary for dentists to be able to perform cardiopulmonary resuscitation (CPR) to increase the chance of saving patient's life in emergency situation. In this paper, we conducted a survey study to evaluate to what extent dentists actually understood CPR practice and if they had experience in handling emergency situations in practice. Method: The survey was done for members of the Korean Dental Society of Anesthesiology (KDSA), who had great interest in CPR and for whom survey-by-mail was convenient. We had selected 472 members of the KDSA with a dental license and whose office address and contact information were appropriate, and sent them a survey questionnaire by mail asking about the degree of their CPR understanding and if they had experience of handling emergency questions before. Statistical analyses -frequency analysis, chi-square test, ANOVA, and so on- were performed by use of IBM SPSS Statistics 19 for each question. Result: Among 472 people, 181 responded (38.4% response rate). Among the respondents were 134 male and 47 female dentists. Their average age was $40.4{\pm}8.4$. In terms of practice type, there were 123 private practitioners (68.0%), 20 professors (11.0%), 16 dentists-in-service (8.8%), 13 residents (specialist training) (7.2%) and 9 military doctors (5%). There were 125 dentists (69.1%) who were specialists or receiving training to be specialist, most of whom were oral surgeon (57, 31.5%) and pediatric dentists (56, 30.9%). There were 153 people (85.0%) who received CPR training before, and 65 of them (35.9%) were receiving regular training. When asked about the ratio of chest pressure vs mouth-to-mouth respiration when conducting CPR, 107 people (59.1%) answered 30:2. However, only 27.1% of them answered correctly for a question regarding CPR stages, C(Circulation)- A(Airway)- B(Breathing)- D(Defibrillation), which was defined in revised 2010 CPR practice guideline. Dentists who had experience of handling emergency situations in their practice were 119 (65.6%). The kinds of emergency situations they experienced were syncope (68, 37.6%), allergic reactions to local anesthetic (44, 24.3%), hyperventilation (43, 23.8%), seizure (25, 13.8%), hypoglycemia (15, 8.3%), breathing difficulty (14, 7.8%), cardiac arrest (11, 6.1%), airway obstruction (6, 3.3%), intake of foreign material and angina pectoris (4, 2.2%), in order of frequency. Most respondents answered that they handled the situation appropriately under the given emergency situation. In terms of emergency equipment they had blood pressure device (70.2%), pulse oximetry (69.6%), Bag-Valve-Mask (56.9%), emergency medicine (41.4%), intubation kit (29.8%), automated external defibrillator (23.2%), suction kit (19.3%) and 12 people (6.6%) did not have any equipment. In terms of confidence in handling emergency situation, with 1-10 point scale, their response was $4.86{\pm}2.41$ points. The average point of those who received regular training was $5.92{\pm}2.20$, while those who did not was $4.29{\pm}2.29$ points (P<0.001) Conclusion: The result showed they had good knowledge of CPR but the information they had was not up-to-date. Also, they were frequently exposed to the risk of emergency situation during their dental practice but the level of confidence in handling the emergency situation was intermediate. Therefore, regular training of CPR to prepare them for handling emergency situation is deemed necessary.

• Journal of East-West Nursing Research
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• v.1 no.1
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• pp.82-98
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• 1997

The purpose of this study was to determine pattern of the stress perceived by stroke patients over time. The ultimate goal of the research is to provide data to help nurses to design the plan of nursing care of the stroke patients both in the hospital and at home. A total of 57 admitted stroke patients were collected from one general hospital in Seoul from June, 12 to September, la, 1993. The data were collected for three phases(within one week after leaving the hospital). The tools for this study, three scales were used ; Stress scale developed by the investigator. Constitution classifing scale designed by Kho(1984), and Self-care measuring scale by Kang(1984). Data were analyzed in four steps using statistical analysis. First, demographic data were determined by descriptive statistics. Second. the pattern of stress perceived by stroke patients across three phases was measured using repeated measures ANOVA. Third, stress of stroke patients classified by constitution, paralyzed area. and attack frequency were measured using ANOVA or t-test, and the pattern of stress by group over time was determined using paired t-test in post hoc test. Fourth. Pearson correlation coefficients were calculated to determine the relationship between the stress and self-care activities. The results of this study are ; 1. The pattern of stress across three phases ; There was a decrease of the stress across three phases. In general. psychological stress as the highest among three phases(F=36.92. P=.000). There was a statistically significant difference of the physical stress(F=34.55, p=.000), the psychological stress (F=15.49, p=.0005) and the social stress (F=24.71. p=.000) among three phases. There was a statistically significant difference of the stress between the first phase (on admission) and the second phase(before leaving the hospital) and was a decrease of the stress (t =6.36. p=.000). 2. The pattern of stress of stroke patients classified by constitution across three phases ; Stroke patients classified as So-Eum perceived the highest stress among three groups(Tae-Eum, So-Eum. So-Yang). There was no statistically significant difference of stress according to the constitution of stroke patients among three phases. Hence. stress was not influenced by the constitution of stroke patients, but there was a statistically significant difference of stress over time. 3. The pattern of stress of stroke patients classified by the paralyzed area across three phases ; Right paralyzed stroke patients perceived higher stress than left paralyzed stroke patients. There was, however, no statistically significant difference of stress between two groups except 2nd phase. There was no statistically significant difference of the perception of stress bet ween the right and left paralyzed stroke patients. 4. The pattern of stress of stroke patients classified by the frequency of the relapse of the disease across three phases ; Stress was higher in stroke patients who had the relapse of the disease twice more than the first time. There was, however, no statistically significant difference of stress between two groups. There was no statistically significant difference of stress of stroke patients according to the relapse of the disease among three phases. Hence, stress was no influenced by the relapse of the disease. 5. The relationship between the stress and self-care activities ; There was a negative relationship between the stress and self-care activities each phase(on admission, r= -.1563 ; before leaving the hospital, r= -.4030 ; after leaving the hospital, r= -.5291). Hence, the higher the self-care activities, the lower the stress. This study has three important findings. First finding was that psychological stress perceived by stroke patients was the highest among three phases. The second finding was that factors such as the constitution, the paralyzed area, and the relapse of the disease did not have an influence on the stress perceived by stroke patients across three phases(on admission, before leaving the hospital, after leaving the hospital). There was a statistically significant decrease of the stress perceived by stroke patients across three phases. The third finding was that there was a negative relationship between the self-care ability and stress. In this study, these findings have implications for nursing care for the rehabilitation of stroke patients and suggest the need of nursing intervention to promote the self-care ability and to support the psychological self-esteem of stroke patients.

• The korean journal of orthodontics
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• v.30 no.5 s.82
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• pp.657-668
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• 2000

The purpose of this study was to evaluate the amount and interrelationship of the soft tissue of nose and maxillary changes and to identify the nasal morphologic features that indicate susceptibility to nasal deflection in such a manner that they would be useful in presurgical prediction of nasal changes after maxillary advancement surgery in skeletal Class III malocclusion. The sample consisted of 25 adult patients (13 males and 12 females) who had severe anteroposterior skeletal discrepancy. The patients had received presurgical orthodontic treatment. They underwent a Le Fort I advancement osteotomy, rigid internal fixation, alar cinch suture and V-Y advancement lip closure. The presurgical and postsurgical lateral cephalograms and lateral and frontal facial photographs were evaluated. The computerized statistical analysis was carried out. Soft tissue of nose change to h point change ratios were calculated by regression equations. The results were as follows 1. The correlation of maxillary hard tissue horizontal changes and nasal soft tissue vortical changes were high and the ${\beta}_0$ for soft tissue to ADV were 0.228 at ANt, 0.257 at SNt. 2. The correlation of maxillary hard tissue and nasal soft tissue horizontal changes were high and the ${\beta}_0$ for soft tissue to ADV were 0.484 at ANt, 0.431 at SNt, 0.806 at Sn. 3. The correlation of maxillary hard tissue horizontal changes and width changes of ala of nose were high and the ${\beta}_0$ lot alar base width ratio to ADV were 0.002. 4. The DRI, Prominence of nose, Pre-Op CA is not a quantitative measure that can be used clinically to improve the predictability of vertical and horizontal nasal tip deflection. In this study, increases in nasal tip projection and anterosuperior rotation occur when there is an anterior vector of maxillary movement. These nasal changes were Quantitatively correlated to magnitude of maxillary(A point) movement.

• The korean journal of orthodontics
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• v.30 no.1 s.78
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• pp.43-52
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• 2000

Hemifacial microsomia ( HFM ) is the second most common craniofacial abnormalies. HFM represnted a spectrum of clinical findings such as hypoplasia of the mandibular ramus and condyle, confinement of maxilla growth, external and/or middle ear defects, involvement of some cranial suture, buccal soft tissue, facial nerve, and muscles in the affected side. HFM often showed progressive facial asymmetry and occlusal plane slanting to the affected side with growth. There were several reports about asymmetry of tooth maturation, hypodontia, delayed eruption, enamel hypoplasia in HFM. Since teeth develope in close association with size and morphology of the maxillary and the mandible, it is highly likely that dental changes will be present in HFM. So the Purpose of this study was to investigate the differences of the primary and the permanent teeth dimensions in the maxillary and the mandibular dentition between the affected and the non-affected side of HFM.. The sample of this study consisted of 34 unilateral HFM Patients (18 males and 16 females, average age : 5 year 11 months old). The authors examined the mesiodistal and the faciolingual dimensions of the primary and the permanent teeth and performed statistical study by using paired t-test. The results were as follows 1. The mesiodistal dimensions of the mandibular second primary molar and the mandibular first permanent molar in the affected side of HFM were significantly smaller than those of non-affected side. But there were no significant differences in the anterior teeth and the mandibular first primary molar. It means that a gradient of severity from anterior teeth to posterior teeth was found in the mandibular dentition. 2. Although there were no significant differences in the faciolingual dimensions of the primary and the permanent teeth in the maxillary and the mandibular dentition between the affected and non-affected side of HFM, there were general trend of compensatory increase in faciolingual dimension of the mandibular primary and the permanent teeth in the affected side Therefore these results showed that HFM might affect on the abnormality of tooth dimension, especially the most posterior teeth, in the affected side of the mandible.

• The korean journal of orthodontics
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• v.30 no.1 s.78
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• pp.53-66
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• 2000

This study was performed to find out the effect of projection errors on cephalometric linear and angular measurements according to head rotation during taking lateral cephalometric radiographs. Seventeen skulls with permanent dentition and no gross asymmetry were obtained from the Department of Anatomy, Medical School, Chosun University. Total 527 x-ray films were taken with $1^{\circ}$ interval from the reference position($0^{\circ}$) to ${\pm}15^{\circ}$ around the vertical axis (Z axis) which is perpendicular to the midpoint of the line connecting the center of two ear rods in submento-vertex direction. Statistical analysis was performed by paired t-test if there were statistically significant differences between the mean of the reference position($0^{\circ}$) and that of each rotation angle. The following results were obtained. 1. The projection errors of angular measurements were smaller than those of linear measurements. 2. The projection errors of angular measurements including midline landmarks were smaller than those including bilateral landmarks. 3. The horizontal linear measurements were gradually decreased when the stroll was rotated toward the film, but slightly increased and then decreased when the skull was rotated toward the focal spot. However, the changes were smaller in focal direction. 4. The projection errors of horizontal linear measurements were larger than those of vertical linear measurements. 5. The projection errors of vertical linear measurements were increased with increased distance from the rotation axis to vertical measurements. It is concluded that the use of angular measurements rather than linear measurements is recommended to minimize the projection errors.

• The korean journal of orthodontics
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• v.27 no.5 s.64
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• pp.771-779
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• 1997

The purpose of this in vitro study was to evaluate the effects of different acid etching times on the enamel surface morphology, shear bond strength and debonding failure mode of orthodontic attachment. Ninety six extracted human mandibular premolars were divided into eight groups of twelve teeth. The buccal surfaces were etched with $37\%$, phosphoric acid for 5, 10, 15, 30, 45, 60, 90 and 120 seconds, respectively. Two teeth from each group were used for scanning electron microscope examination. On the etched buccal surfaces of remaining teeth, orthodontic attachments(lingual buttons) were bonded with light cured orthodontic adhesive. Twenty foot hours after bonding, a Instron universal testing machine was used to determine shear bond strength of orthodontic attachment to enamel. After debonding, bases of orthodontic attachments and enamel surfaces were examined under stereoscopic microscope to determine failure mode. Statistical analysis of the data was carried out with one nay ANOVA and Duncan's multiple range test The results were as follows; 1. There was no statistically significant difference in shear bond strengths between the various etching times(p<0.05). 2. The failure modes of orthodontic attachments had some differences. In 5, 10 and 15 seconds etching groups, the percentage of adhesive/enamel interface failure was higher than that of adhesive/attachment interface failure. On the contrary, in 30, 45, 60, 90 and 120 seconds etching groups, the results were reversed. 3. The etching patterns of enamel surfaces had a great variation. So, we could not find any correlation between etching pattern and bond strength. 4. The findings in this study indicate that in vitro reduction of the etching me to 5 seconds maintains clinically acceptable bond strength. However, further study is required to determine the cause of failure mode in 5, 10 and 15 seconds groups.

• Journal of dental hygiene science
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• v.12 no.4
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• pp.359-367
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• 2012

This study was to evaluate the influence of dental caries prevention-related concerned and perceived in Korean adults and oral health behavior of their first child if they had children. A cross-sectional study in 1,014 adults over 19 years old were conducted in Korean adults, asked to answer a computer-assisted telephone interview regarding their oral health-related knowledge, behavior, concerned of caries prevention and child's behaviors such as frequencies of tooth brushing, chewing the xylitol gum and dental checkup. The statistical analysis was done by using the SPSS 19.0 program (IBM Co., Armonk, NY, USA). Awareness of caries prevention in the female than male, 40~49 years old age group was higher. Parents of school-age children were higher level of awareness of the dental caries prevention than other group. As knowledge and behavior of dental caries prevention were higher, the child's conduct regular oral health checkups, fluoride topical application and dental sealant was significantly higher. The higher the concerned of caries preventive, the intention of oral health behaviors and child's oral health behaviors was more increased. Awareness of caries prevention had effect on the perception of the impact of the child's oral health behaviors.

• Journal of dental hygiene science
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• v.12 no.4
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• pp.392-403
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• 2012

This study aims at providing the basic data to help establish the right identity of dental hygienist and develop the work of dental hygienists, and thereby investigating the effect of patients' perception of dental hygienist on their social demand of dental hygienist, by conducting a survey of 300 patients visiting dentists around Busan-Gyeongnam region from April 7, 2012 to April 25, 2012. The collected data is statistically analyzed by SPSS (Statistical Packages for Social Science 14.0. SPSS Inc., Chicago, IL, USA). First, I analyzed the frequency by suggesting the demographic and descriptive characteristics of data, and conducted t-test and One-Way ANOVA at 5% of significance level to figure out the degree of perception and social demand of dental hygienists depending on customers' reason for visiting dentists, and also conducted regression analysis to find the effect of the perception of dental hygienist on patient's social demand of dental hygienist. The result suggests that as the perception of the dental hygienists' role, the social demand for dental hygienists' image increases, but as perception of dental hygienists' image increases, the social demand of dental hygienists' image decreases. Therefore, it suggests that as the knowledge about dental hygienists increases, patients demand their service more, while the perception of their image lowers the social demand for their image. It turns out that as the knowledge of dental hygienists increase, the social demand for the knowledge also increases.