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.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.
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.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.
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.Comparison of complications in patients with NSTEMI according to the timing of invasive intervention: early versus delayed
Chang Wan SEO ; Ha Young PARK ; Han Byeol KIM ; Jai Woog KO ; Jun Bae LEE ; Yoon Jung HWANG ; Tae Sik HWANG
Journal of the Korean Society of Emergency Medicine 2025;36(2):54-62
Objective:
Acute coronary syndrome often requires urgent intervention. The 2023 European Society of Cardiology guidelines recommend invasive procedures within 24 hours for high-risk cases. Nevertheless, there have been limited studies on non-ST-segment elevation myocardial infarction (NSTEMI) in South Korea. This study compared the risk of complications based on the timing of intervention.
Methods:
A retrospective observational study was conducted on patients with chest pain and elevated high-sensitivity troponin T from January to December 2021 in the emergency department. Patients were categorized into early (≤24 hr) and late (>24 hr) intervention groups. Primary outcomes (death, restenosis, or stroke) at 12 months were compared. Survival and subgroup analyses were performed to examine the factors affecting the outcomes in the two groups.
Results:
Three hundred seventy six patients were enrolled in the study, and 115 patients were excluded. Among 261 patients, 106 and 155 patients were in the early intervention group (≤24 hr), and late intervention group (>24 hr), respectively. The primary outcome (death or restenosis) showed no significant difference (hazard ratio [HR] in the early intervention group at 12 mo; 1.03; 95% confidence interval [CI], 0.63-1.70; P=0.905). However, risk of stroke was lower in the early intervention group (HR in the early, 0.08; 95% CI, 0.00-0.66; P=0.013). Subgroup analysis showed no significant advantage for early intervention.
Conclusion
In NSTEMI patients, early intervention does not reduce death or restenosis but lowers stroke incidence. No specific risk factors favored early intervention.
8.Comparison of complications in patients with NSTEMI according to the timing of invasive intervention: early versus delayed
Chang Wan SEO ; Ha Young PARK ; Han Byeol KIM ; Jai Woog KO ; Jun Bae LEE ; Yoon Jung HWANG ; Tae Sik HWANG
Journal of the Korean Society of Emergency Medicine 2025;36(2):54-62
Objective:
Acute coronary syndrome often requires urgent intervention. The 2023 European Society of Cardiology guidelines recommend invasive procedures within 24 hours for high-risk cases. Nevertheless, there have been limited studies on non-ST-segment elevation myocardial infarction (NSTEMI) in South Korea. This study compared the risk of complications based on the timing of intervention.
Methods:
A retrospective observational study was conducted on patients with chest pain and elevated high-sensitivity troponin T from January to December 2021 in the emergency department. Patients were categorized into early (≤24 hr) and late (>24 hr) intervention groups. Primary outcomes (death, restenosis, or stroke) at 12 months were compared. Survival and subgroup analyses were performed to examine the factors affecting the outcomes in the two groups.
Results:
Three hundred seventy six patients were enrolled in the study, and 115 patients were excluded. Among 261 patients, 106 and 155 patients were in the early intervention group (≤24 hr), and late intervention group (>24 hr), respectively. The primary outcome (death or restenosis) showed no significant difference (hazard ratio [HR] in the early intervention group at 12 mo; 1.03; 95% confidence interval [CI], 0.63-1.70; P=0.905). However, risk of stroke was lower in the early intervention group (HR in the early, 0.08; 95% CI, 0.00-0.66; P=0.013). Subgroup analysis showed no significant advantage for early intervention.
Conclusion
In NSTEMI patients, early intervention does not reduce death or restenosis but lowers stroke incidence. No specific risk factors favored early intervention.
9.Comparison of complications in patients with NSTEMI according to the timing of invasive intervention: early versus delayed
Chang Wan SEO ; Ha Young PARK ; Han Byeol KIM ; Jai Woog KO ; Jun Bae LEE ; Yoon Jung HWANG ; Tae Sik HWANG
Journal of the Korean Society of Emergency Medicine 2025;36(2):54-62
Objective:
Acute coronary syndrome often requires urgent intervention. The 2023 European Society of Cardiology guidelines recommend invasive procedures within 24 hours for high-risk cases. Nevertheless, there have been limited studies on non-ST-segment elevation myocardial infarction (NSTEMI) in South Korea. This study compared the risk of complications based on the timing of intervention.
Methods:
A retrospective observational study was conducted on patients with chest pain and elevated high-sensitivity troponin T from January to December 2021 in the emergency department. Patients were categorized into early (≤24 hr) and late (>24 hr) intervention groups. Primary outcomes (death, restenosis, or stroke) at 12 months were compared. Survival and subgroup analyses were performed to examine the factors affecting the outcomes in the two groups.
Results:
Three hundred seventy six patients were enrolled in the study, and 115 patients were excluded. Among 261 patients, 106 and 155 patients were in the early intervention group (≤24 hr), and late intervention group (>24 hr), respectively. The primary outcome (death or restenosis) showed no significant difference (hazard ratio [HR] in the early intervention group at 12 mo; 1.03; 95% confidence interval [CI], 0.63-1.70; P=0.905). However, risk of stroke was lower in the early intervention group (HR in the early, 0.08; 95% CI, 0.00-0.66; P=0.013). Subgroup analysis showed no significant advantage for early intervention.
Conclusion
In NSTEMI patients, early intervention does not reduce death or restenosis but lowers stroke incidence. No specific risk factors favored early intervention.
10.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
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Depression*
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Humans
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Mindfulness
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Outpatients
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Reproducibility of Results*