1.The influence of fitness and type of luting agents on bonding strength of fiber-reinforced composite resin posts
Kkot-Byeol BAE ; Hye-Yoon JUNG ; Yun-Chan HWANG ; Won-Mann OH ; In-Nam HWANG
Journal of Dental Rehabilitation and Applied Science 2023;39(4):187-194
Purpose:
A mismatched size in the post and post space is a common problem during post-fixation. Since this discordance affects the bonding strength of the fiber-reinforced composite resin post (FRC Post), a corresponding luting agent is required. The aim of this study was to evaluate the bonding strength of the FRC post according to the fitness of the fiber post and the type of luting agent. Materials and Methods: Thirty mandibular premolar were endodontic-treated and assigned to two groups according to their prepared post space: Fitting (F) and Mismatching (M). These groups were further classified into three subgroups according to their luting agent: RelyX Unicem (ReX), Luxacore dual (Lux), and Duolink (Duo). A push-out test was performed to measure the push-out bond strengths. The fractured surfaces of each cross-section were then examined, and the fracture modes were classified.
Results
In the ReX and Duo subgroups, the F group had a higher mean bond strength; however, the Lux subgroup had no significant difference between the F and M groups. In the analysis of the failure modes, the ReX subgroup had only adhesive failures between the cement and dentin. Conclusion: The result of this study showed that the bond strength of an FRC post was influenced by the type of luting agent and the mismatch between the diameter of the prepared post space and that of the post.
2.Effect of surface sealant on surface roughness of dental composite with different surface roughness
Dong-Ah SHIN ; Seon-Ju JIN ; Kkot-Byeol BAE ; In-Nam HWANG
Journal of Dental Rehabilitation and Applied Science 2023;39(4):195-203
Purpose:
This study aimed to evaluate the influence of surface sealants on the surface roughness of composite resins.
Materials and Methods:
The study used microfilled composite resin (Metafil CX, Sun Medical Co.) and hybrid composite resin (Aelite™ LS posterior, Bisco). Sixty specimens (8 mm in diameter and 4 mm in height) of each composite resin type were prepared and divided into 3 groups. Each specimen was ground with 600, 1000, and 2000-grit sandpaper. The Surface roughness (Ra) values were measured using a surface roughness tester (SJ-301, Mytutoyo) before and after surface sealant application. Surface sealants, BisCover™ LV (Bisco), Optiguard® (Kerr), and Seal-n-Shine™ (Pulpdent), were applied to the specimens, as instructed and observed by scanning electron microscope (JSM-7500, JEOL) and atomic force microscope (MultiMode IV, Veeco Instruments).
Results:
Specimens ground with 600-grit sandpaper coated with surface sealants exhibited significantly lower Ra values than the untreated group (P < 0.05).Specimens ground with 1000 and 2000-grit sandpaper showed statistically no difference. There was no significant difference in surface roughness among BisCover™ LV, Optiguard®, and Seal-n-Shine™. SEM and AFM revealed remarkably decreased microdefects on the surfaces of composite resins after surface sealant application.
Conclusion
Surface sealants can influence surface roughness when applied on the rough surface of composite resins but not on highly polished composite resins.
3.Validation of high-sensitivity troponin I levels for major adverse cardiac events in low risk chest pain patients
Hyun Jin RYU ; Ha Young PARK ; Tae Sik HWANG ; Han Byeol KIM ; Ju Hong LEE
Journal of the Korean Society of Emergency Medicine 2023;34(6):586-598
Objective:
This study examined whether the efficiency of the level of detection (LOD) and upper reference limit (URL) for high-sensitivity cardiac troponin I (hs-cTnI) is increased when major adverse cardiovascular events (MACEs) occur in patients with low-risk chest pain who visit the emergency department (ED) and how long they stay in the ED.
Methods:
The URL for hs-cTnI used in the hospital improved from 0.04 ng/mL (LOD <0.0041 ng/mL) in 2018 to 19.8 pg/mL (LOD <2.3 pg/mL) in 2019. In these two years, the occurrence of MACEs, frequency of hs-cTnI follow-up in the ER, and the length of stay in the ER were compared. In addition, the three calculated risk assessment scores for the safety level of early discharge were compared.
Results:
In 2018, there were six MACEs out of 120 patients (5.0%), no cardiac deaths, one acute myocardial infarction (AMI), and five unplanned coronary revascularizations. In 2019, six MACEs out of 105 patients (5.7%) were all unplanned coronary revascularizations without any cardiac deaths or AMIs.
Conclusion
Although the level of hs-cTnI measurement was improved, there was no difference in the incidence of MACEs in patients with low-risk chest pain who were discharged from the ED, and the number of hs-cTnI follow-ups and time in the ED increased. Interestingly, there were only short-term MACEs and no medium-term MACEs. In addition, there was little to no coronary artery occlusion disease. The risk assessment score combined with hs-cTnI improved the predictive performance for MACEs.
4.Guillain-Barré Syndrome Associated with Shiga Toxin-Producing and Enterotoxigenic Escherichia coli Infection
Jaeho KANG ; Jeong Ik EUN ; Hyunyoung HWANG ; Byeol-A YOON ; Kyong Jin SHIN
Journal of the Korean Neurological Association 2022;40(3):256-258
GuillainBarré syndrome (GBS) is the inflammatory neuropathy that affects the myelin and nodal or paranodal areas of peripheral nerves. Immunoglobulin G GM1 antibody is well known as the cause of GBS associated with Campylobacter jejuni infection. However, the relationship between other specific infectious agents and autoantibodies is not yet well elucidated in patients with GBS. Recently we have experienced a case with GBS associated with antiGM1 and phosphatidic acid complex antibody that occurred after Shiga toxinproducing and enterotoxigenic Escherichia coli enteritis.
5.Effect of the cutting flute of the orthodontic miniscrew on insertion and removal torque
Cheol-Soo PARK ; Byoung-Gu LIM ; Eun-Kyu WON ; Jo-Yeon HWANG ; Byeol HWANG ; Jeong-Hui JI ; Woo-Yong JEON ; Min-Ho LEE ; Tae-Sung BAE
Korean Journal of Dental Materials 2021;48(1):53-60
The purpose of this study was to evaluate the structural characteristics of the thread length of orthodontic mini-screws and the effects of insertion and removal torques according to the formation of the cutting flute. Two types of mini-screws were made, with a thread length of 6.0 mm and a thread length of 3.3 mm. In order to examine the effect of flute formation, the experiment group was divided into a miniscrew test group with flute formation and an experiment group without flute formation. To evaluate the effect of flute formation, two flutes were formed at 180°on the circumference, and at the tip of the mini screw, up to 4 mm for thread length of 6.0 mm and 2.4 mm for thread length of 3.3 mm. A biomechanical test block formed of 2 mm cortical bone and 10 mm cancellous bone was used to eliminate the influence of the difference in cortical bone thickness and bone density according to the insertion site. 1 mm diameter guide hole was drilled on the test block and the mini-screw was placed vertically. Using a 0.1 N·cm precision digital torque gauge, the maximum torque value was recorded at this time by embedding it to the top of the screw under a static load of 1.2 kg and the value when it was removed in the opposite direction. The insertion torque values for the 6.0 mm and 3.3 mm length mini screws were (29.53±1.84) N·cm and (26.84±2.15) N·cm, and the removal torque values are (14.50±1.37) N·cm and (13.15±2.89) N·cm, respectively.There were no statistically significant differences (P>0.05). The flute of 6.0 mm mini-screws had no statistically significant difference in both insertion and removal torque values and increased to (30.13±1.97) N·cm and (18.65±1.10) N·cm (P>0.05). In experiments with 3.3 mm mini-screws, the insertion and removal torque values decreased to (20.99±3.94) N·cm and (11.32±2.03) N·cm, respectively, showing a statistically significant decrease only in the insertion torque values (P<0.05). The insertion and removal torque values of the mini-screw were not significantly increased even when the screw length was doubled, and the flute formation effect was different with the screw length.
6.Effect of the cutting flute of the orthodontic miniscrew on insertion and removal torque
Cheol-Soo PARK ; Byoung-Gu LIM ; Eun-Kyu WON ; Jo-Yeon HWANG ; Byeol HWANG ; Jeong-Hui JI ; Woo-Yong JEON ; Min-Ho LEE ; Tae-Sung BAE
Korean Journal of Dental Materials 2021;48(1):53-60
The purpose of this study was to evaluate the structural characteristics of the thread length of orthodontic mini-screws and the effects of insertion and removal torques according to the formation of the cutting flute. Two types of mini-screws were made, with a thread length of 6.0 mm and a thread length of 3.3 mm. In order to examine the effect of flute formation, the experiment group was divided into a miniscrew test group with flute formation and an experiment group without flute formation. To evaluate the effect of flute formation, two flutes were formed at 180°on the circumference, and at the tip of the mini screw, up to 4 mm for thread length of 6.0 mm and 2.4 mm for thread length of 3.3 mm. A biomechanical test block formed of 2 mm cortical bone and 10 mm cancellous bone was used to eliminate the influence of the difference in cortical bone thickness and bone density according to the insertion site. 1 mm diameter guide hole was drilled on the test block and the mini-screw was placed vertically. Using a 0.1 N·cm precision digital torque gauge, the maximum torque value was recorded at this time by embedding it to the top of the screw under a static load of 1.2 kg and the value when it was removed in the opposite direction. The insertion torque values for the 6.0 mm and 3.3 mm length mini screws were (29.53±1.84) N·cm and (26.84±2.15) N·cm, and the removal torque values are (14.50±1.37) N·cm and (13.15±2.89) N·cm, respectively.There were no statistically significant differences (P>0.05). The flute of 6.0 mm mini-screws had no statistically significant difference in both insertion and removal torque values and increased to (30.13±1.97) N·cm and (18.65±1.10) N·cm (P>0.05). In experiments with 3.3 mm mini-screws, the insertion and removal torque values decreased to (20.99±3.94) N·cm and (11.32±2.03) N·cm, respectively, showing a statistically significant decrease only in the insertion torque values (P<0.05). The insertion and removal torque values of the mini-screw were not significantly increased even when the screw length was doubled, and the flute formation effect was different with the screw length.
7.The Clinical Characteristics of Acinar Cell Carcinoma in the Pancreas.
Hye Un KIM ; Je Kyu RYU ; Sae Byeol CHOI ; Ho Kyoung HWANG ; Kyung Sik KIM ; Dong Sup YOON ; Woo Jung LEE
Korean Journal of Hepato-Biliary-Pancreatic Surgery 2009;13(1):54-59
Acinar cell carcinoma (ACC) is a very rare type of pancreatic cancer that makes up less than 1% of all pancreatic cancers. The prognosis of ACC is very poor and the mean survival interval is only 18-19 months. The only effective treatment is currently early radical resection. MATERIALS AND METHODS: To determine ACC`s clinical characteristics and the treatment efficacy, we conducted a retrospective chart review to study the clinical characteristics, laboratory findings, pathology and treatment responses of 10 ACC patients among 3042 pancreatic cancer patients who were diagnosed in Severance Hospital and Kangnam Severance Hospital of Yonsei University, College of Medicine from 1988.01.01 to 2008.12.31. RESULTS: The 10 ACC patients were 6 males and 4 females. The mean age of the 10 ACC patients was 53.2 years. The most of the patients (7/10) complained the pain on the epigastric area and there was no jaundice in 8 patients (80%). Unfortunately, regional or distant metastases were founded in 8 patients (80%) at the time of the first diagnosis. The initial mean CA19-9 level was increased to 73.5 U/ml (range: 0.1~350.0 U/ml). Six of 10 patients underwent radical surgery and 4 of 10, including 1 with open and closure, were treated with conservative treatment. The median survival interval was 22.4 months with operative treatment and 1.5 months with conservative treatment. The median overall survival interval was 19.4 months. The median disease free survival was 17 months. The liver was the most common recurrent site (3 cases). CONCLUSIONS: An early radical resection is currently the best and only treatment for ACC, but in rare cases, post-operative adjuvant chemotherapy shows hopeful results and so this requires more study.
Acinar Cells
;
Carcinoma, Acinar Cell
;
Chemotherapy, Adjuvant
;
Disease-Free Survival
;
Female
;
Humans
;
Jaundice
;
Liver
;
Male
;
Neoplasm Metastasis
;
Pancreas
;
Pancreatic Neoplasms
;
Prognosis
;
Retrospective Studies
;
Treatment Outcome
8.The Reliability and Validity of the Korean Version of Behavioral Activation for Depression Scale.
Ji Hye OH ; Na Ri HWANG ; Yun Ji CHA ; Eun Byeol LEE ; Kee Hong CHOI ; Ho Jun SEO
Journal of Korean Neuropsychiatric Association 2017;56(2):89-97
OBJECTIVES: The Behavioral Activation of Depression Scale (BADS) has been reported to be a valid tool for assessing the different behavioral aspects of depression, such as activation, rumination or avoidance, and functional impairment. The aim of this study was to assess the reliability and validity of the Korean version of BADS (K-BADS). METHODS: A sample of 196 outpatients completed the K-BADS and the data were analyzed for internal consistency and factor structures. An additional 51 outpatients re-filled the K-BADS after two weeks for the test-retest reliability. To test for the validity, the Hospital Anxiety and Depression Scale (HADS), Working Alliance Inventory (WAI), Drug Attitude Inventory-10 (DAI-10), and Mindfulness Attention Awareness Scale (MAAS) were administered. RESULTS: Internal consistency of K-BADS was good (Cronbach's alpha=0.843) and principal component factor analysis revealed the four-factor structure. The K-BADS showed a reasonable test-retest reliability (r=0.863, p<0.001). The total score of K-BADS correlated significantly with the total scores of the HADS depression (r=−0.694) and HADS anxiety (r=−0.681). No correlations were found between the K-BADS and the K-WAI (r=0.170) and between the K-BADS and the K-DAI-10 (r=0.311). CONCLUSION: The K-BADS is a reliable and valid instrument for measuring the behavioral activation for depression in Korean patients with depressive symptoms.
Anxiety
;
Depression*
;
Humans
;
Mindfulness
;
Outpatients
;
Reproducibility of Results*
9.Classify the Acute Drug Intoxication Patients with Poisoning Severity Score(PSS) and Calculate the Optimal Cutoff Value of PSS, PSSsum to Predict Poor Prognosis.
Hyun Woo PARK ; Ha Young PARK ; Han Byeol KIM ; Keon Woo PARK ; Sang Hun LEE ; Hyun Wook LEE ; Je Won LEE ; Tae Sik HWANG
Journal of The Korean Society of Clinical Toxicology 2018;16(2):75-85
PURPOSE: This study examined the Poisoning Severity Score (PSS) from acute poisoning patients, to determine the relationships among the PSS, PSSsum, the primary outcome (prolonged stay at the ER over 24 hours, general ward and ICU admission and the application of intubation and mechanical ventilator, and the administration of inotropes). METHODS: A retrospective study was conducted through the EMR for 15 months. The PSS grade was classified according to the evidence of symptoms and signs. The differences in the primary outcomes between the PSS of when a single organ was damaged, and the PSS, PSSsum combined with the grade of when multiple organs were damaged, were studied. The cutoff value was calculated using the receiving operating characteristics (ROC) curve. RESULTS: Of the 284 patients; 85 (29.9%) were men with a mean age of 48.8 years, and their average arrival time to the ER was 4.4±6.7 hours. The most frequently used drug was hypnotics. The number of patients with PSS grade 0, 1, 2, 3, and 4 was 17, 129, 122, 24, and one, respectively. No ICU admissions, application of intubation and mechanical ventilators, administration of inotropes were observed among the patients with PSS grades 0 and 1 but only on patients with PSS grades 2 to 4. At PSS, when separating the patients according to the number of damaged organs, 17 had no symptoms, 133 had one organ damaged, 75 had two organs damaged, 36 had three organs damaged, and 23 had four organs damaged. Significant differences were observed between increasing number of damaged organs and the primary outcome. CONCLUSION: Among the acute poisoning patients, the PSS was higher in severity when the grade was higher. The number of damaged organs and the primary outcome showed meaningful statistical differences. This study confirmed that when the patients' PSS>2 and PSSsum>5, the frequency of ICU admission was higher, and they were considered to be severe with an increased prescription risk of application of intubation and mechanical ventilator, and the administration of inotropes.
Humans
;
Hypnotics and Sedatives
;
Intubation
;
Male
;
Patients' Rooms
;
Poisoning*
;
Prescriptions
;
Prognosis*
;
Retrospective Studies
;
Ventilators, Mechanical
10.Color comparison of glaze-treated multi-coloured lithium disilicate and zirconia
Byeol HWANG ; Jeong-Hui JI ; Cheol-Soo PARK ; Jaewoo SHIN ; Junghwan LEE ; Min-Ho LEE ; Tae-Sung BAE
Korean Journal of Dental Materials 2021;48(1):1-14
The purpose of this study was to investigate the effect of glazing treatment of multi-colored zirconia disc and lithium disilicate block on the optical properties. From an Ultra Translucent Multi-Layered (UTML) disc containing 50% cubic crystal and a lithium disilicate-based Amber Mill Direct (AMD) block, the 1.2 mm thick specimens of the upper layer (T), the center (M), and the lower layer (B) were prepared. Three types of paste glaze of InSync Glaze Paste, IPS E.max Ceram Glaze Paste, and Amber Ceram G7 Glaze Paste were applied and fired to a uniform thickness on the surface of the specimen. CIE L * , a * , b * values were measured using a spectrophotometer and contrast and translucency were calculated. The bonding interface with the glaze layer was observed using HR FE-SEM. In the glazed groups, L * value increased, but a * value and b * value decreased. The translucency value measured in the untreated group was statically higher in the AMD groups than in UTML groups (P<0.05).The translucency did not show a significant difference before and after glazing treatment in the UTML group (P>0.05), but significantly decreased compared to the untreated group after glazing treatment in the AMD group (P<0.05). The contrast ratios generally increased after glaze treatment compared to the untreated group. Since the glaze treatment can affect the optical properties of ceramic restorations, the choice of glaze should be considered important for the desired color by the dental technician.