1.A Study on Reproducible Locations for Evaluating Masseter Muscle Function with Ultrasonography
Hyun-Jeong PARK ; Jong-Mo AHN ; Sun-Kyoung YU ; Ji-Won RYU
Journal of Oral Medicine and Pain 2025;50(1):25-33
Purpose:
This study aimed to identify reproducible locations for evaluating masseter muscle function by measuring its thickness using ultrasonography (US). The study focused on comparing two measurement locations: the thickest part of the masseter muscle during ultrasonographic scanning (TMUS) and the most prominent part during clenching (PMC).
Methods:
Forty healthy adults (20 males and 20 females) participated in the study. US images were obtained from both sides of the masseter muscle under resting and clenching conditions. Measurements were taken at the TMUS and PMC locations, and the clenching-to-resting (C/R) ratio was calculated. Intra- and inter-rater reliability were assessed using intraclass correlation coefficients (ICCs), and the agreement between the two locations was further analyzed using Bland–Altman (BA) plots.
Results:
The measurements at both TMUS and PMC showed high intra- and inter-rater agreement, with no significant difference in measurements between the two locations.However, the PMC location demonstrated slightly higher ICC values (0.94) compared to TMUS (0.91). The C/R ratio for PMC showed higher consistency (0.89) compared to TMUS (0.65). BA plots indicated that the agreement between TMUS and PMC was slightly better during clenching than at rest, with smaller mean differences in clenching (–0.06 mm) than resting (–0.13 mm). Additionally, the number of measurements outside the upper and lower limits was lower during clenching (10) than at rest (13).
Conclusions
Both TMUS and PMC locations demonstrated reliable measurements, but the PMC location showed slightly better consistency across different muscle states. The findings suggest that PMC provides a more reproducible and standardized approach for masseter muscle assessment, making it a better choice for both clinical practice and research in evaluating masticatory function.
2.Dental Age Estimation in Children Using Convolution Neural Network Algorithm: A Pilot Study
Byung-Yoon ROH ; Hyun-Jeong PARK ; Kyung-Ryoul KIM ; In-Soo SEO ; Yeon-Ho OH ; Ju-Heon LEE ; Chang-Un CHOI ; Yo-Seob SEO ; Ji-Won RYU ; Jong-Mo AHN
Journal of Oral Medicine and Pain 2024;49(4):118-123
Purpose:
Recently, deep learning techniques have been introduced for age estimation, with automated methods based on radiographic analysis demonstrating high accuracy. In this study, we applied convolutional neural network (CNN) techniques to the lower dentition area on orthopantomograms (OPGs) of children to develop an automated age estimation model and evaluate its accuracy for use in forensic dentistry.
Methods:
In this study, OPGs of 2,856 subjects aged 3-14 years were analyzed. The You Only Look Once (YOLO) V8 object detection technique was applied to extract the mandibular dentition area on OPGs, designating it as the region of interest (ROI). First, 200 radiographs were randomly selected, and were used to train a model for extracting the ROI. The trained model was then applied to the entire dataset. For the CNN image classification task, 80% of OPGs were allocated to the training set, while the remaining 20% were used as the test set. A transfer learning approach was employed using the ResNet50 and VGG19 backbone models, with an ensemble technique combining these models to improve performance. The mean absolute error (MAE) on the test set was used as the validation metric, and the model with the lowest MAE was selected.
Results:
In this study, the age estimation model developed using mandibular dentition region from OPGs achieved MAE and root mean squared error (RMSE) values of 0.501 and 0.742, respectively, on the test set, and MAE and RMSE values of 0.273 and 0.354, respectively, on the training set.
Conclusions
The automated age estimation model developed in this study demonstrated accuracy comparable to that of previous research and shows potential for applications in forensic investigations. Increasing the sample size and incorporating diverse deep learning techniques are expected to further enhance the accuracy of future age estimation models.
3.Orofacial Pain and Nonodotogenic Toothache of Cardiac Origin:Case Report
Jong-Mo AHN ; Ji-Won RYU ; Hyun-Jeong PARK
Journal of Oral Medicine and Pain 2024;49(1):18-21
Orofacial pain has various causes, making it challenging to differentiate from dentalrelated diseases based solely on symptoms. Toothache, usually attributed to pathological changes in the pulp and periodontal tissue, is the most common cause of orofacial pain and relatively easy to diagnose. However, distinguishing orofacial pain and nonodontogenic toothache due to myofascial, neuropathic, neurovascular, paranasal sinus and cardiac originating, and psychogenic pain presents diagnostic challenges that may result in incorrect treatment. Therefore, dentists must recognize that orofacial pain can arise from not only dental issues but also other causes. This case report explores the necessary considerations in diagnosing orofacial pain and nonodontogenic toothache by examining the diagnoses of patients presenting at the dental hospital with orofacial pain and nonodontogenic toothache of cardiac origin.
4.Colon cancer: the 2023 Korean clinical practice guidelines for diagnosis and treatment
Hyo Seon RYU ; Hyun Jung KIM ; Woong Bae JI ; Byung Chang KIM ; Ji Hun KIM ; Sung Kyung MOON ; Sung Il KANG ; Han Deok KWAK ; Eun Sun KIM ; Chang Hyun KIM ; Tae Hyung KIM ; Gyoung Tae NOH ; Byung-Soo PARK ; Hyeung-Min PARK ; Jeong Mo BAE ; Jung Hoon BAE ; Ni Eun SEO ; Chang Hoon SONG ; Mi Sun AHN ; Jae Seon EO ; Young Chul YOON ; Joon-Kee YOON ; Kyung Ha LEE ; Kyung Hee LEE ; Kil-Yong LEE ; Myung Su LEE ; Sung Hak LEE ; Jong Min LEE ; Ji Eun LEE ; Han Hee LEE ; Myong Hoon IHN ; Je-Ho JANG ; Sun Kyung JEON ; Kum Ju CHAE ; Jin-Ho CHOI ; Dae Hee PYO ; Gi Won HA ; Kyung Su HAN ; Young Ki HONG ; Chang Won HONG ; Jung-Myun KWAK ;
Annals of Coloproctology 2024;40(2):89-113
Colorectal cancer is the third most common cancer in Korea and the third leading cause of death from cancer. Treatment outcomes for colon cancer are steadily improving due to national health screening programs with advances in diagnostic methods, surgical techniques, and therapeutic agents.. The Korea Colon Cancer Multidisciplinary (KCCM) Committee intends to provide professionals who treat colon cancer with the most up-to-date, evidence-based practice guidelines to improve outcomes and help them make decisions that reflect their patients’ values and preferences. These guidelines have been established by consensus reached by the KCCM Guideline Committee based on a systematic literature review and evidence synthesis and by considering the national health insurance system in real clinical practice settings. Each recommendation is presented with a recommendation strength and level of evidence based on the consensus of the committee.
5.Clinical Practice Guidelines for Oropharyngeal Dysphagia
Seoyon YANG ; Jin-Woo PARK ; Kyunghoon MIN ; Yoon Se LEE ; Young-Jin SONG ; Seong Hee CHOI ; Doo Young KIM ; Seung Hak LEE ; Hee Seung YANG ; Wonjae CHA ; Ji Won KIM ; Byung-Mo OH ; Han Gil SEO ; Min-Wook KIM ; Hee-Soon WOO ; Sung-Jong PARK ; Sungju JEE ; Ju Sun OH ; Ki Deok PARK ; Young Ju JIN ; Sungjun HAN ; DooHan YOO ; Bo Hae KIM ; Hyun Haeng LEE ; Yeo Hyung KIM ; Min-Gu KANG ; Eun-Jae CHUNG ; Bo Ryun KIM ; Tae-Woo KIM ; Eun Jae KO ; Young Min PARK ; Hanaro PARK ; Min-Su KIM ; Jungirl SEOK ; Sun IM ; Sung-Hwa KO ; Seong Hoon LIM ; Kee Wook JUNG ; Tae Hee LEE ; Bo Young HONG ; Woojeong KIM ; Weon-Sun SHIN ; Young Chan LEE ; Sung Joon PARK ; Jeonghyun LIM ; Youngkook KIM ; Jung Hwan LEE ; Kang-Min AHN ; Jun-Young PAENG ; JeongYun PARK ; Young Ae SONG ; Kyung Cheon SEO ; Chang Hwan RYU ; Jae-Keun CHO ; Jee-Ho LEE ; Kyoung Hyo CHOI
Journal of the Korean Dysphagia Society 2023;13(2):77-106
Objective:
Dysphagia is a common clinical condition characterized by difficulty in swallowing. It is sub-classified into oropharyngeal dysphagia, which refers to problems in the mouth and pharynx, and esophageal dysphagia, which refers to problems in the esophageal body and esophagogastric junction. Dysphagia can have a significant negative impact one’s physical health and quality of life as its severity increases. Therefore, proper assessment and management of dysphagia are critical for improving swallowing function and preventing complications. Thus a guideline was developed to provide evidence-based recommendations for assessment and management in patients with dysphagia.
Methods:
Nineteen key questions on dysphagia were developed. These questions dealt with various aspects of problems related to dysphagia, including assessment, management, and complications. A literature search for relevant articles was conducted using Pubmed, Embase, the Cochrane Library, and one domestic database of KoreaMed, until April 2021. The level of evidence and recommendation grade were established according to the Grading of Recommendation Assessment, Development and Evaluation methodology.
Results:
Early screening and assessment of videofluoroscopic swallowing were recommended for assessing the presence of dysphagia. Therapeutic methods, such as tongue and pharyngeal muscle strengthening exercises and neuromuscular electrical stimulation with swallowing therapy, were effective in improving swallowing function and quality of life in patients with dysphagia. Nutritional intervention and an oral care program were also recommended.
Conclusion
This guideline presents recommendations for the assessment and management of patients with oropharyngeal dysphagia, including rehabilitative strategies.
6.In vitro comparison of the accuracy of an occlusal plane transfer method between facebow and POP bow systems in asymmetric ear position
Dae-Sung KIM ; So-Hyung PARK ; Jong-Ju AHN ; Chang-Mo JEONG ; Mi-Jung YUN ; Jung-Bo HUH ; So-Hyoun LEE
The Journal of Advanced Prosthodontics 2023;15(5):271-280
PURPOSE:
. This in vitro study aimed to compare the accuracy of the conventional facebow system and the newly developed POP (PNUD (Pusan National University Dental School) Occlusal Plane) bow system for occlusal plane transfer in asymmetric ear position.
MATERIALS AND METHODS:
. Two dentists participated in this study, one was categorized as Experimenter 1 and the other as Experimenter 2 based on their clinical experience with the facebow (1F, 2F) and POP bow (1P, 2P) systems. The vertical height difference between the two ears of the phantom model was set to 3 mm. Experimenter 1 and Experimenter 2performed the facebow and POP bow systems on the phantom model 10 times each, and the transfer accuracy was analyzed. The accuracy was evaluated by measuring the angle between the reference virtual plane (RVP) of the phantom model and the experimental virtual plane (EVP) of the upper mounting plate through digital superimposition. All data were statistically analyzed using a paired t-test (P < .05).
RESULTS:
. Regardless of clinical experience, the POP bow system (0.53° ± 0.30 (1P) and 0.19° ± 0.18 (2P) for Experimenter 1 and 2, respectively) was significantly more accurate than the facebow system (1.88° ± 0.50 (1F) and 1.34° ± 0.25 (2F), respectively) in the frontal view (P < .05). In the sagittal view, no significant differences were found between the POP bow system (0.92° ± 0.50 (1P) and 0.73° ± 0.42 (2P) for Experimenter 1 and 2, respectively) and the facebow system (0.82° ± 0.49 (1F) and 0.60° ± 0.39 (2F), respectively), regardless of clinical experience (P > .05).
CONCLUSION
. In cases of asymmetric ear position, the POP bow system may transfer occlusal plane information more accurately than the facebow system in the frontal view, regardless of clinical experience.
7.Dental Age Estimation Using the Demirjian Method: Statistical Analysis Using Neural Networks
Byung-Yoon ROH ; Jong-Seok LEE ; Sang-Beom LIM ; Hye-Won RYU ; Su-Jeong JEON ; Ju-Heon LEE ; Yo-Seob SEO ; Ji-Won RYU ; Jong-Mo AHN
Korean Journal of Legal Medicine 2023;47(1):1-7
In children and adolescents, dental age estimation is performed with the development of the teeth. Various statistical analysis methods have been used to determine the relationship between age and dental maturity and develop an accurate method of age calculation. This study attempted to apply a neural network model for the statistical analysis of dental age estimation in children and evaluated its applicability. This study used 1196 panoramic radiographs of patients aged 3–16 years, and 996 and 200 were randomly classified into training and test sets, respectively. The dental maturity of the mandibular left teeth was evaluated using Demirjian's method, the neural network model using the backpropagation algorithm was derived using training sets, and the errors were evaluated using 100 radiographs of each male and female as test sets. In addition, multiple linear regression analysis was conducted on the same training set, and the error was calculated by applying it to the test set and comparing it with the error of the neural network model. In the neural network model, the mean absolute error (MAE) and root mean squared error (RMSE) were 0.589 and 0.783 in male subjects and 0.529 and 0.760 in female subjects, respectively. In the multiple linear regression model, the MAE and RMSE were 0.600 and 0.748 in male subjects and 0.566 and 0.789 in female subjects, respectively. When applying the neural network model to the statistical analysis of the dental developmental stage, the results were as accurate as those of conventional statistical analysis methods. This study’s approach is expected to be useful for estimating the ages of children.
8.Long-term follow-up results of cytarabine-containing chemotherapy for acute promyelocytic leukemia
Young Hoon PARK ; Dae-Young KIM ; Yeung-Chul MUN ; Eun Kyung CHO ; Jae Hoon LEE ; Deog-Yeon JO ; Inho KIM ; Sung-Soo YOON ; Seon Yang PARK ; Byoungkook KIM ; Soo-Mee BANG ; Hawk KIM ; Young Joo MIN ; Jae Hoo PARK ; Jong Jin SEO ; Hyung Nam MOON ; Moon Hee LEE ; Chul Soo KIM ; Won Sik LEE ; So Young CHONG ; Doyeun OH ; Dae Young ZANG ; Kyung Hee LEE ; Myung Soo HYUN ; Heung Sik KIM ; Sung-Hyun KIM ; Hyukchan KWON ; Hyo Jin KIM ; Kyung Tae PARK ; Sung Hwa BAE ; Hun Mo RYOO ; Jung Hye CHOI ; Myung-Ju AHN ; Hwi-Joong YOON ; Sung-Hyun NAM ; Bong-Seog KIM ; Chu-Myong SEONG
The Korean Journal of Internal Medicine 2022;37(4):841-850
Background/Aims:
We evaluated the feasibility and long-term efficacy of the combination of cytarabine, idarubicin, and all-trans retinoic acid (ATRA) for treating patients with newly diagnosed acute promyelocytic leukemia (APL).
Methods:
We included 87 patients with newly diagnosed acute myeloid leukemia and a t(15;17) or promyelocytic leukemia/retinoic acid receptor alpha (PML-RARα) mutation. Patients received 12 mg/m2/day idarubicin intravenously for 3 days and 100 mg/m2/day cytarabine for 7 days, plus 45 mg/m2/day ATRA. Clinical outcomes included complete remission (CR), relapse-free survival (RFS), overall survival (OS), and the secondary malignancy incidence during a 20-year follow-up.
Results:
The CR, 10-year RFS, and 10-year OS rates were 89.7%, 94.1%, and 73.8%, respectively, for all patients. The 10-year OS rate was 100% for patients that achieved CR. Subjects were classified according to the white blood cell (WBC) count in peripheral blood at diagnosis (low-risk, WBC < 10,000/mm3; high-risk, WBC ≥ 10,000/mm3). The low-risk group had significantly higher RFS and OS rates than the high-risk group, but the outcomes were not superior to the current standard treatment (arsenic trioxide plus ATRA). Toxicities were similar to those observed with anthracycline plus ATRA, and higher than those observed with arsenic trioxide plus ATRA. The secondary malignancy incidence after APL treatment was 2.7%, among the 75 patients that achieved CR, and 5.0% among the 40 patients that survived more than 5 years after the APL diagnosis.
Conclusions
Adding cytarabine to anthracycline plus ATRA was not inferior to anthracycline plus ATRA alone, but it was not comparable to arsenic trioxide plus ATRA. The probability of secondary malignancy was low.
9.Real-World Efficacy Data and Predictive Clinical Parameters for Treatment Outcomes in Advanced Esophageal Squamous Cell Carcinoma Treated with Immune Checkpoint Inhibitors
Jwa Hoon KIM ; Bokyung AHN ; Seung-Mo HONG ; Hwoon-Yong JUNG ; Do Hoon KIM ; Kee Don CHOI ; Ji Yong AHN ; Jeong Hoon LEE ; Hee Kyoung NA ; Jong Hoon KIM ; Yong-Hee KIM ; Hyeong Ryul KIM ; Hyun Joo LEE ; Sung-Bae KIM ; Sook Ryun PARK
Cancer Research and Treatment 2022;54(2):505-516
Purpose:
This study aimed to evaluate the real-world efficacy of immune checkpoint inhibitors (ICIs), and to identify clinicolaboratory factors to predict treatment outcomes in patients with advanced esophageal squamous cell carcinoma (ESCC) receiving ICIs.
Materials and Methods:
Sixty patients with metastatic or unresectable ESCC treated with nivolumab (n=48) or pembrolizumab (n=12) as ≥ second-line treatment between 2016 and 2019 at Asan Medical Center were included.
Results:
The median age of the patients was 68 years (range, 52 to 76 years), and 93.3% were male. Most patients had metastatic disease (81.7%) and had been previously treated with fluoropyrimidines, platinum, and taxane. In 53 patients with measurable disease, the overall response rate and disease control rate were 15.1% and 35.8%, respectively. With a median follow-up duration of 16.0 months, the median progression-free survival (PFS) and overall survival (OS) were 1.9 months (95% confidence interval [CI], 1.54 to 2.19) and 6.4 months (95% CI, 4.77 to 8.11), respectively. After multivariate analysis, recent use of antibiotics, low prognostic nutrition index (< 35.93), high Glasgow Prognosis Score (≥ 1) at baseline, and ≥ 1.4-fold increase in neutrophil-to-lymphocyte ratio after one cycle from baseline were significantly unfavorable factors for both PFS and OS. Younger age (< 65 years) was a significant factor for unfavorable PFS and hyponatremia (< 135 mmol/L) for unfavorable OS.
Conclusion
The use of ICIs after the failure of chemotherapy showed comparable efficacy in patients with advanced ESCC in real practice; this may be associated with host immune-nutritional status, which could be predicted by clinical and routine laboratory factors.
10.Cardiac Manifestations of Coronavirus Disease 2019 (COVID-19): a Multicenter Cohort Study
Minkwan KIM ; Jong-Ho NAM ; Jang-Won SON ; Sun Oh KIM ; Nak-Hoon SON ; Chul-Min AHN ; Chi Young SHIM ; Geu-Ru HONG ; In-Cheol KIM ; Jinwoo CHOI ; Seung-Mo KANG ; Yeoung Ho CHOI ; Hae Kyoung YOON ; Jae-Sun UHM ; In Hyun JUNG
Journal of Korean Medical Science 2020;35(40):e366-
Background:
This study aimed to investigate the cardiac manifestations of coronavirus disease 2019 (COVID-19).
Methods:
From February to March 2020, we prospectively and retrospectively enrolled consecutive patients diagnosed with COVID-19. Patient's data such as the demographic characteristics, symptoms, vital signs, laboratory and radiologic findings, electrocardiographic, and echocardiographic data, including the global longitudinal strain (GLS) of both ventricles, were obtained.
Results:
Forty patients (median age, 58 years; 50% men) were enrolled in the initial analysis. Patients were classified into severe and nonsevere groups based on the current guidelines. The 13 patients in the severe group were significantly older, had a greater prevalence of bilateral pneumonia and leukocytosis, and higher aspartate transaminase levels than patients in the nonsevere group. Patients in the severe group had a slightly lower left ventricular ejection fraction (LVEF) than those in the nonsevere group (median [interquartile range], 61.0% [58.5%, 62.3%] vs. 66.7% [60.6%, 69.8%], P = 0.015). In a subgroup of 34 patients in whom GLS could be analyzed, patients in the severe group had a significantly impaired left ventricular GLS (LVGLS) than those in the nonsevere group (−18.1% [−18.8%, −17.1%] vs. −21.7% [−22.9%, −19.9%], P = 0.001). There were no significant differences in total wall (RVGLS total , −19.3% [−23.9%, −18.4%] vs. −24.3% [−26.0%, −22.6%], P = 0.060) and free wall (RVGLS fw , −22.7% [−27.2%, −18.6%] vs. −28.8% [−30.4%, −24.1%], P = 0.066) right ventricle GLS (RVGLS).
Conclusion
Patients with severe COVID-19 had lower LVEF and LVGLS. RVGLS was not different between patients with severe and nonsevere COVID-19.

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