1.A comparison of the fracture resistances of endodontically treated mandibular premolars restored with endocrowns and glass fiber post-core retained conventional crowns.
Jing GUO ; Zhiming WANG ; Xuesheng LI ; Chaoyang SUN ; Erdong GAO ; Hongbo LI
The Journal of Advanced Prosthodontics 2016;8(6):489-493
PURPOSE: This in-vitro study aimed to evaluate the fracture resistances and failure modes of endodontically treated mandibular premolars restored with endocrowns and conventional post-core retained crowns. MATERIALS AND METHODS: Thirty mandibular premolars were assigned into three groups (n=10): GI, intact teeth; GE, teeth with endocrowns; GC, teeth with conventional post-core supported crowns. Except for the teeth in group GI, all specimens were cut to 1.5 mm above the cementoenamel junction and endodontically treated. Both endocrowns and conventional crowns were fabricated from lithium-disilicate blocks using a CEREC 3D CAD/CAM unit. All specimens were subjected to thermocycling and then to 45° oblique compressive load until fracture occurred. The fracture resistance and failure mode of each specimen were recorded. Data were analyzed with one-way ANOVA and LSD Post Hoc Test (α=.05). RESULTS: The fracture resistances of GE and GC were significantly lower than that of GI (P<.01), while no significant difference was found between GE and GC (P=.702). As of the failure mode, most of the specimens in GE and GC were unfavorable while a higher occurrence of favorable failure mode was presented in GI. CONCLUSION: For the restoration of mandibular premolar, endocrown shows no advantage in fracture resistance when compared with the conventional method. Both of the two methods cannot rehabilitate endodontically treated teeth with the same fracture resistances that intact mandibular premolars have.
Bicuspid*
;
Crowns*
;
Glass*
;
Lysergic Acid Diethylamide
;
Methods
;
Tooth
;
Tooth Cervix
2.Shear bond strength of indirect composite material to monolithic zirconia.
Fatih SARI ; Asli SECILMIS ; Irfan SIMSEK ; Semih OZSEVIK
The Journal of Advanced Prosthodontics 2016;8(4):267-274
PURPOSE: This study aimed to evaluate the effect of surface treatments on bond strength of indirect composite material (Tescera Indirect Composite System) to monolithic zirconia (inCoris TZI). MATERIALS AND METHODS: Partially stabilized monolithic zirconia blocks were cut into with 2.0 mm thickness. Sintered zirconia specimens were divided into different surface treatment groups: no treatment (control), sandblasting, glaze layer & hydrofluoric acid application, and sandblasting + glaze layer & hydrofluoric acid application. The indirect composite material was applied to the surface of the monolithic zirconia specimens. Shear bond strength value of each specimen was evaluated after thermocycling. The fractured surface of each specimen was examined with a stereomicroscope and a scanning electron microscope to assess the failure types. The data were analyzed using one-way analysis of variance (ANOVA) and Tukey LSD tests (α=.05). RESULTS: Bond strength was significantly lower in untreated specimens than in sandblasted specimens (P<.05). No difference between the glaze layer and hydrofluoric acid application treated groups were observed. However, bond strength for these groups were significantly higher as compared with the other two groups (P<.05). CONCLUSION: Combined use of glaze layer & hydrofluoric acid application and silanization are reliable for strong and durable bonding between indirect composite material and monolithic zirconia.
Hydrofluoric Acid
;
Lysergic Acid Diethylamide
;
Microscopy, Electron, Scanning
;
Shear Strength
;
Surface Properties
3.Assessment of foodservice management practices in the employee feeding operations according to type of workers.
Journal of the Korean Dietetic Association 1997;3(1):63-73
This study was conducted to evaluate the industry foodservice management practices and to suggest guidelines for the effective foodservice management. The survey for the analysis was conducted through the questionnaires to dietitians. They were divided into two groups: the site color worker and the blue color worker. The questionnaires were received for a response rate of 73.2%. Statistical data analysis was completed using the SAS programs for descriptive analysis, chi-square test, T-test, F-test, and Fisher's LSD. The results of the study can be summarized as follows: 1) The level of education of dietitians and food cost in the employee feeding operations for the blue color worker was lower than the employee feeding operations for the white color worker. 2) The labor productivity indices were not significantly different according to types of workers. But in the employee feeding operations for the blue color worker, full-time foodservice employees worked more than 10.7 hour per week than their counterpart. This indicates the full-time foodservice employees in the employee feeding operations for the blue color worker performed more loaded work compared to the employee feeding operations for the white color worker. 3) Equipped rate of facilities in the employee feeding operations for the blue color worker was low especially in the food preparation and cooking processes.
Cooking
;
Data Interpretation, Statistical
;
Education
;
Efficiency
;
Lysergic Acid Diethylamide
;
Nutritionists
;
Surveys and Questionnaires
4.Evaluation of the accuracy of linear and angular measurements on panoramic radiographs taken at different positions.
Sima NIKNESHAN ; Mohamad SHARAFI ; Naghmeh EMADI
Imaging Science in Dentistry 2013;43(3):191-196
PURPOSE: This study assessed the accuracy of linear and angular measurements on panoramic radiographs taken at different positions in vitro. MATERIALS AND METHODS: Two acrylic models were fabricated from a cast with normal occlusion. Straight and 75degrees mesially and lingually angulated pins were placed, and standardized panoramic radiographs were taken at standard position, at an 8degrees downward tilt of the occlusal plane compared to the standard position, at an 8degrees upward tilt of the anterior occlusal plane, and at a 10degrees downward tilt of the right and left sides of the model. On the radiographs, the length of the pins above (crown) and below (root) the occlusal plane, total pin length, crown-to-root ratio, and angulation of pins relative to the occlusal plane were calculated. The data were subjected to repeated measures ANOVA and LSD multiple comparisons tests. RESULTS: Significant differences were noted between the radiographic measurements and true values in different positions on both models with linear (P<0.001) and those with angulated pins (P<0.005). No statistically significant differences were observed between the angular measurements and baselines of the natural head posture at different positions for the linear and angulated pins. CONCLUSION: Angular measurements on panoramic radiographs were sufficiently accurate and changes in the position of the occlusal plane equal to or less than 10degrees had no significant effect on them. Some variations could exist in the pin positioning (head positioning), and they were tolerable while taking panoramic radiographs. Linear measurements showed the least errors in the standard position and 8degrees upward tilt of the anterior part of the occlusal plane compared to other positions.
Dental Occlusion
;
Dimensional Measurement Accuracy
;
Head
;
Lysergic Acid Diethylamide
;
Posture
;
Radiography, Panoramic
5.Effects of Health Belief on Fall Prevention Activities of Emergency Room Nurses.
Min Kyoung PARK ; Hyun Young KIM
Journal of Korean Academy of Nursing Administration 2014;20(2):176-186
PURPOSE: The purpose of this study was to analyze factors affecting fall prevention activities of emergency room (ER) nurses based on their health belief factors (perceived susceptibility, perceived benefits, perceived severity, perceived barriers, and cues to action). METHODS: The study design was a descriptive survey using questionnaires which were given to 127 emergency room nurses from two regional emergency medical centers, four local emergency medical centers, and two local emergency medical facilities. Data were analyzed using descriptive analysis, t-test, one-way ANOVA with LSD test, Pearson correlation, and multiple regressions. RESULTS: ER nurses' fall prevention activities had a mean of 3.78+/-0.50. Eight individual characteristics and health belief factors accounted for 30.8% of the fall prevention activities. Fall prevention activities were found to be positively affected by emergency medical facilities, perceived benefits, and cues to action and negatively affected by factors, such as ER career and perceived severity. CONCLUSION: The results indicate that it is necessary to formulate a plan for enhancing perceived benefits and cues to action to improve fall prevention activities. In addition, fall prevention activities should be encouraged for ER nurses who have worked in local medical institutions for less than 1 year or more than 5 years.
Accident Prevention
;
Accidental Falls
;
Cues
;
Emergencies
;
Emergency Service, Hospital*
;
Health Behavior
;
Lysergic Acid Diethylamide
;
Surveys and Questionnaires
6.A Validation Study for the Korean Version of Delirium Rating Scale-Revised-98 (K-DRS-98).
Kyoung Ok LIM ; Soo Young KIM ; Yang Hyun LEE ; Sun Woo LEE ; Jeong Lan KIM
Journal of Korean Neuropsychiatric Association 2006;45(6):518-526
OBJECTIVE: This study was conducted to develop and to validate the Korean version of Delirium Rating Scale-Revised-98 (K-DRS-98), which is a scale for diagnosing delirium and evaluating its severity. METHOD: After developing the K-DRS-98, 102 patients were rated by it among 4 diagnostic groups, such as delirium (N=25), dementia (N=27), schizophrenia (N=25) and others (N=25). To test for reliability, K-DRS-98 was independently administered by two psychiatrist. To test for validity, Korean version of Mini-Mental State Examination (MMSE-K) and Clinical Global Impression (CGI) were administered simultaneously. Statistical analysis was done with SPSS window version 12 package and statistical significance was p<0.05. RESULT: Internal consistencies (Cronbach alpha) of two raters were 0.867 and 0.858, respectively. Inter-rater reliability (kappa) was 0.893 for severity items of K-DRS-98 and kappa value of diagnosis items was 0.969. In Delirium group, Pearson correlation coefficients (gamma) of K-DRS-98 were -0.682 for MMSE-K and 0.667 for CGI. In comparison Delirium group with Others, ANOVA post hoc multiple comparison LSD was statistically significant (p<0.001). The cutoff score to diagnosis of delirium can be recommended 16 for severity items and 21.5 for total score, respectively. CONCLUSION: The K-DRS-98 was showed good reliability and validity for the assessment of delirium. The K-DRS-98 is an easy and useful tool for diagnosing delirium and assessing its severity.
Delirium*
;
Dementia
;
Diagnosis
;
Humans
;
Lysergic Acid Diethylamide
;
Psychiatry
;
Reproducibility of Results
;
Schizophrenia
7.Clinical Nurses' Knowledge and Attitudes on Pain Management.
Journal of Korean Academy of Adult Nursing 2000;12(3):369-383
The purpose of this study was to understand clinical nurses' knowledge and attitudes on pain management. The subject of the study were 254 nurses working at two hospitals affiliated with a university in Seoul. The questionnaires included four areas: general knowledge on pain, knowledge on the use of analgesia, knowledge and implementation on the pain assessment scales and pain interventions and nurses' general characteristics. The data were analyzed with descriptive statistics, analysis of variance, LSD test and t-test using SPSS statistical package. The results were as follows. 1. The mean score of the general pain knowledge was 61.46 and that of knowledge on the use of analgesia was 52.19. 2. Most nurses(74%) answered with hesitation about injecting narcotic analgesia to patients. 3. The pain assessment scale which nurses knew (57.5%) and used(48.0%) extremely was a simple descriptive scale. 4. The pain intervention which nurses knew (94.5%) and implemented(92.1%) extremely was to inject analgesia. 5. The number of nurses who had learned about pain management was 49 of 254(19.3%). 6. Nurses' knowledge on the use of analgesia was of relevance to having learned pain management, but general pain knowledge was not so relevant. According to this research, I suggest the following. 1. It is necessary to develop an education program with actual practice and intervention which nurses can perform for themselves. 2. It is necessary to continuously educate about pain management in clinical wards.
Analgesia
;
Education
;
Humans
;
Lysergic Acid Diethylamide
;
Pain Management*
;
Pain Measurement
;
Seoul
;
Weights and Measures
;
Surveys and Questionnaires
8.Construction of spvD gene deletion mutant and compensation strains in Salmonella enteritidis and its effects on Caco-2 cells.
Yue HOU ; Bo PANG ; Zhe LI ; Qiang ZHAO ; Jie LIU
Chinese Journal of Preventive Medicine 2022;56(4):486-493
Objective: To analyze the effects of spvD gene on invasion and intracellular proliferation of Caco-2 cells and in order to provide insight into the function of that gene and the underlying mechanism of Salmonella caused infection. Methods: Functional verification of spvD gene deletion mutant and compensation strain. The deletion mutant strain was constructed through a suicide plasmid-mediated homologous recombination. The compensation plasmid constructed by cloning the coding sequence of spvD by PCR into plasmid pBAD33 was mobilized into the deletion mutant by conjugation and the pBAD33 was introduced into wild strains and deleted mutant strains as control. The relative expression of spvD mRNA was detected by quantitative reverse transcription PCR. In order to analyze the virulence of spvD against Caco-2 cells, Caco-2 cells was cocultured with wild type Salmonella enteritidis carrying spvD gene, the deletion mutant strain and compensation strain respectively. The expression level of spvD mRNA and the the number of Salmonella enteritidis after Caco-2 cells intervention were compared between the three groups by LSD-t test, and the invasion rate was compared by χ2 test. Results: The expression level of spvD mRNA in wild type Salmonella enteritidis was set as unit "1", the deletion mutant strain was "0.00", and the compensation strain was "2.60" (LSD-twild, deleted=1.11, P=0.31; LSD-twild, compensation=-1.77, P=0.13; LSD-t deleted, compensation=-2.88, P=0.03), which confirmed the successful construction of the deletion mutant strain and the compensation strain. The invasion experiment results of the above three Salmonella enteritidis strains on Caco-2 cells showed that the invasion rate of wild strain was 0.23%, the invasion rate of deleted mutant strain was 0.16%, and the invasion rate of compensation strain was 0.16%, with no statistical significance (χ2=1.13, P=0.570). By comparing the number of Salmonella enteritidis at different time points after Caco-2 cells intervention, it was discovered that the number of Salmonella enteritidis in wild strains (6.50×106 CFU/ml) and compensation strains (7.25×106 CFU/ml) was significantly increased than that in deletion mutant strain (1.90×106 CFU/ml) after 16 h coculture (LSD-twild, deleted=7.95, P=0.00; LSD-twild, compensation=-1.27, P=0.25; LSD-t deleted, compensation=-9.22, P=0.00). Conclusion: It is not considered that spvD gene can affect the invasion of Salmonella enteritidis on Caco-2 cells, but the gene can promote the reproduction of Salmonella enteritidis in Caco-2 cells.
Caco-2 Cells
;
Gene Deletion
;
Humans
;
Lysergic Acid Diethylamide
;
RNA, Messenger/genetics*
;
Salmonella enteritidis/genetics*
9.Effect of surface treatments of fiber posts on bond strength to composite resin cores.
Journal of Korean Academy of Conservative Dentistry 2010;35(3):173-179
The purpose of the present study was to compare the influence of post-surface treatment with silane, hydrogen peroxide, hydrofluoric acid or sandblasting and to investigate the effect of silane in combination of the other treatments on the microtensile bond strength between fiber posts and composite resins for core build-up. Thirty-two glass-fiber posts (FRC Postec Plus, Ivoclar Vivadent, Schaan, Liechtenstein) were divided into eight groups according to the different surface pretreatments performed: silane application (S); immersion in 28% hydrogen peroxide (HP); immersion in hydrogen peroxide followed by application of silane (HP-S); immersion in 4% hydrofluoric acid gel (HF); immersion in hydrofluoric acid gel followed by application of silane (HF-S); sandblasting with aluminum oxide particles (SB); sandblasting followed by application of silane (SB-S). In control group, no surface treatment was performed. The composite resin (Tetric Flow, Ivoclar Vivadent, Schaan, Liechtenstein) was applied onto the posts to produce the composite cylinder specimen. It was sectioned into sticks to measure the microtensile bond strength. The data was analyzed with one-way ANOVA and LSD test for post hoc comparison (p < 0.05). Post pretreatment with sandblasting enhanced the interfacial strength between the fiber posts and core materials. Moreover, sand-blasting followed by application of silane appears to be the most effective method that can improve the clinical performance of glass fiber posts.
Acrylic Resins
;
Aluminum Oxide
;
Composite Resins
;
Glass
;
Hydrofluoric Acid
;
Hydrogen Peroxide
;
Immersion
;
Lysergic Acid Diethylamide
;
Polyurethanes
;
Waxes
10.Drug Abuse and Psychosis: New Insights into Drug-induced Psychosis.
Suji HAM ; Tae Kyoo KIM ; Sooyoung CHUNG ; Heh In IM
Experimental Neurobiology 2017;26(1):11-24
Addictive drug use or prescribed medicine abuse can cause psychosis. Some representative symptoms frequently elicited by patients with psychosis are hallucination, anhedonia, and disrupted executive functions. These psychoses are categorized into three classifications of symptoms: positive, negative, and cognitive. The symptoms of DIP are not different from the symptoms of schizophrenia, and it is difficult to distinguish between them. Due to this ambiguity of distinction between the DIP and schizophrenia, the DIP animal model has been frequently used as the schizophrenia animal model. However, although the symptoms may be the same, its causes are clearly different in that DIP is acquired and schizophrenia is heritable. Therefore, in this review, we cover several DIP models such as of amphetamine, PCP/ketamine, scopolamine, and LSD, and then we also address three schizophrenia models through a genetic approach with a new perspective that distinguishes DIP from schizophrenia.
Amphetamine
;
Anhedonia
;
Classification
;
Executive Function
;
Hallucinations
;
Humans
;
Lysergic Acid Diethylamide
;
Models, Animal
;
Psychotic Disorders*
;
Schizophrenia
;
Scopolamine Hydrobromide
;
Substance-Related Disorders*