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Background@#Degenerative lumbar spondylolisthesis (DLS) is frequently associated with lumbar spinal stenosis (LSS) and conservative treatments such as epidural steroid injection do not have long-term benefits in LSS patients with DLS. This study evaluated the effectiveness of percutaneous epidural neuroplasty using a balloon catheter in patients with LSS and DLS. @*Methods@#Patients’ sex, age, body mass index, diabetes, hypertension, stenosis grading, pain duration, location, pain intensity, and medications were retrieved from electronic medical records. At 1, 3, and 6 months following the procedure, data on pain severity, medication usage, and physical functional status were analyzed. A generalized estimating equations model was used at the six-month follow-up. Patients were divided into those with DLS (the spondylolisthesis group) and those without DLS (the no spondylolisthesis group) to evaluate whether the effects of percutaneous epidural neuroplasty using a balloon catheter were different. @*Results@#A total of 826 patients were included (spondylolisthesis: 433 patients, 52.4%; no spondylolisthesis: 393 patients, 47.6%). Age, body mass index, hypertension, pain location, and stenosis grading were statistically different between the two groups. The generalized estimating equations analyses with unadjusted and adjusted estimation revealed a significant improvement in the estimated mean numerical rating scale of pain intensities compared to that at baseline in both groups (P < 0.001). Any adverse events that occurred were minor and temporary. @*Conclusions@#Percutaneous epidural neuroplasty using a balloon catheter may be an alternative treatment option for patients with chronic LSS, regardless of accompanying DLS, who have had failed conservative management.
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Background and Objectives@#Nonpharmacologic interventions (NPIs), such as social distancing and preventive measures, were administered during the coronavirus disease (COVID-19) pandemic, which may influence the incidence of upper respiratory diseases (URDs). The present study compared the incidence of URDs during the COVID-19 pandemic and during the years prior to COVID-19, and investigated the effect of NPIs on URD in the nationwide general population.Subjects and Method This is an epidemiologic study based on the Korean National Health Insurance Database from March 2016 to February 2021. We compared the monthly incidence of URDs from March 2020 to February 2021 (12 months) with that of the past four years. A negative binomial regression model was used to evaluate the annual difference in the incidence of each URD and adjusting temperature, humidity, and the level of particulate matter 10 (PM10). @*Results@#The monthly incidence of ‘the five common URDs’ in 2020 was significantly lower than that in the past four years. The incidence of other chronic diseases, however, such as hypertension and diabetes mellitus, was comparable or higher in the past four years. Among the five common URDs, influenza virus infections decreased most dramatically, nearing 99%, from 296.4-377.1 per 100000 people during the period of 2016 to 2019 to 3.7 per 100000 people in 2020. @*Conclusion@#The present study shows that the incidence of ‘five common URDs’ significantly decreased during the era of COVID-19 in Korea. We believe that nationwide NPI might prevent the transmission of COVID-19 as well as other infectious sources associated with URDs.
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Background and Objectives@#The aim of this study was to identify the frequency of indicators of National Health Insurance (NHI) coverage for positive airway pressure (PAP) therapy and to investigate the changes in patients receiving coverage for PAP therapy after the alterations were made in the insurance benefit standards for mild obstructive sleep apnea (OSA).Subjects and Method We divided the mild OSA patients into two groups according to altered categorization in insurance benefit standards (Mild1: 5≤AHI<10; Mild2: 10≤AHI<15). Eight indicators related to the NHI coverage were identified: four symptoms, three complications, and the minimal blood oxygen saturation during polysomnography (min SpO2) of ≤85% during polysomnography. We also investigated the change in the number of patients receiving insurance benefits under the altered insurance benefit standards. @*Results@#Of the 233 OSA patients, 66, 57, and 110 patients were diagnosed as mild, moderate and severe OSA, respectively. For all of them, the most common indicator related to NHI coverage for PAP therapy was the minimum SpO2 of less than 85% during polysomnography, and the second most common indicator was daytime sleepiness. In the mild OSA group, however, daytime sleepiness was found to be the most common indicator, found in 46 (70%) patients, followed by 38 (58%) patients with min SpO2 of less than 85%. In this group, 59 (89.4%) would have been benefited before the change in the insurance benefit standards whereas 51 patients (77.3%) would now be benefited under the changed insurance benefit standards. @*Conclusion@#Daytime sleepiness was the most commonly observed indicator in the mild OSA patients. The number of patients receiving insurance benefits for PAP therapy significantly decreased after the change was made in the NHI benefit standards for mild OSA
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A 3D-printed resin crown is a novel option for esthetic crown restoration for primary teeth, which are typically bonded with resin cement. The purpose of this study was to evaluate the bonding ability of a 3D printing resin and compare it with other indirect resin materials for crown fabrication. The shear bond strengths of two 3D printing resin materials, Graphy (GP) and NextDent (NXT), and two indirect resin materials, VIPI Block (VIPI) and MAZIC Duro (MZ), were compared in the study. For all materials, the shear bond strength at the interface between the surface of the resin material and resin cement was measured. The mean shear bond strength values of GP, NXT, MZ, and VIPI were 23.29 ± 3.88, 26.14 ± 4.67, 25.41 ± 4.03, and 18.79 ± 4.26 MPa, respectively. There was no significant difference among the SBSs of GP, NXT and MZ except for VIPI. The result of this study indicates that the 3D printing resin meets the essential requirement for clinical use by showing clinically adequate bond strength.
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Background/Aims@#There have been little research on the cancer risks of patients with Peutz-Jeghers syndrome (PJS) in Korea. We aimed to investigate the clinical features of PJS patients and their cancer incidence rate. @*Methods@#Patients with PJS from nine medical centers were enrolled. In those patients diagnosed with cancer, data obtained included the date of cancer diagnosis, the tumor location, and the cancer stage. The cumulative risks of gastrointestinal cancers and extra-gastrointestinal cancers were calculated using the Kaplan-Meier method. @*Results@#A total of 96 PJS patients were included. The median age at diagnosis of PJS was 23.4 years. Cancer developed in 21 of the 96 patients (21.9%). The age of PJS diagnosis was widely distributed (0.9 to 72.4 years). The most common cancers were gastrointestinal cancer (n = 12) followed by breast cancer (n = 6). The cumulative lifetime cancer risk was calculated to be 62.1% at age 60. The cumulative lifetime gastrointestinal cancer risk was 47.1% at age 70. The cumulative lifetime extra- gastrointestinal cancer risk was 40.3% at age 60. @*Conclusions@#PJS onset may occur at any age and the risks of gastrointestinal and extra-gastrointestinal cancer are high. Thorough surveillance of PJS patients for malignancies is vital.
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The introduction of device-assisted enteroscopy (DAE) in the beginning of the 21st century has revolutionized the diagnosis and treatment of diseases of the small intestine. In contrast to capsule endoscopy, the other main diagnostic modality of small bowel diseases, DAE has the unique advantages of allowing the observation of the region of interest in detail and enabling tissue acquisition and therapeutic intervention. As DAE becomes an essential procedure in daily clinical practice, there is an increasing need for correct guidelines on when and how it is to be performed and what technical factors should be taken into consideration. In response to these needs, the Korean Association for the Study of Intestinal Diseases has developed an expert consensus statement on the performance of DAE by reviewing current evidence. This expert consensus statement particularly focuses on the indications, choice of insertion route, therapeutic intervention, complications, and relevant technical points.
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We present the case of a 65-year-old man with maxillary and mandibular complete dentures prepared using neutral zone technique after undergoing mandibulotomy due to tonsil cancer 10 years ago. The patient had a short edentulous period; hence, there was minimal absorption of the alveolar ridge and no abnormality in the motor function of the tongue. However, the retromolar pad was located inside the hamular notch, and the posterior alveolar ridge was relatively turned inward. If the artificial teeth would have been aligned conventionally, the functional space of the tongue would have been invaded, which would have moved the tongue posteriorly thereby reducing the stability of the denture. Therefore, applying the concept of the neutral zone can be a good reference point in such cases. The neutral zone was registered using tissue conditioner, and tooth alignment was performed by making a silicone putty index. The biggest advantage of using neutral zone concept is denture stability. In this case, the neutral zone technique was applied to obtain the lingual alignment limit of the posterior teeth to avoid invasion of the tongue space by the left posterior part of the mandible. Particularly, in case of a patient in which denture stability is difficult to obtain due to absorption of the alveolar ridge, it is believed that better results can be obtained using neutral zone technique.
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With the recent increase in imaging tests, coexisting abdominal aortic aneurysms (AAAs) and thoracic aortic aneurysms (TAAs) are being discovered accidentally.We report two cases of simultaneous endovascular aortic repair (EVAR) and thoracic endovascular aortic repair (TEVAR) for AAA and TAA. Both 74-year-old and 79-year-old male with infrarenal AAA and saccular TAA were treated simultaneously with EVAR and TEVAR. Saccular TAAs were identified in the upper thoracic aorta during the evaluation of AAA. During endograft placement, carotid-subclavian bypass and cerebrospinal fluid (CSF) drainage were performed. Both patients were successfully discharged without spinal cord ischemia. Simultaneous EVAR and TEVAR can be considered for patients with AAA and saccular TAA in the upper thoracic aorta. Moreover, CSF drainage may be necessary to protect the spinal cord.
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BACKGROUND@#Adipose-derived stem cells (ADSCs) exert immunomodulatory effects in the treatment of transplant rejection. This study aimed to evaluate the effects of ADSCs on the skin graft survival in a human-to-rat xenograft transplantation model and to compare single and multiple injections of ADSCs. @*METHODS@#Full-thickness human skin xenografts were transplanted into the backs of Sprague–Dawley rats. The rats were injected subcutaneously on postoperative days 0, 3, and 5. The injections were as follows: triple injections of phosphate-buffered saline (PBS group), a single injection of ADSCs and double injections of PBS (ADSC 9 1 group), and triple injections of ADSCs (ADSC 9 3 group). The immunomodulatory effects of ADSCs on human skin xenografts were assessed. @*RESULTS@#Triple injections of ADSCs considerably delayed cell-mediated xenograft rejection compared with the PBS and ADSC 9 1 groups. The vascularization and collagen type 1–3 ratios in the ADSC 9 3 group were significantly higher than those in the other groups. In addition, intragraft infiltration of CD3-, CD4-, CD8-, and CD68-positive cells was reduced in the ADSC 9 3 group. Furthermore, in the ADSC 9 3 group, the expression levels of proinflammatory cytokine interferon-gamma (IFN-c) were decreased and immunosuppressive prostaglandin E synthase (PGES) was increased in the xenograft and lymph node samples. @*CONCLUSION@#This study presented that triple injections of ADSCs appeared to be superior to a single injection in suppressing cell-mediated xenograft rejection. The immunomodulatory effects of ADSCs are associated with the downregulation of IFN-c and upregulation of PGES in skin xenografts and lymph nodes.
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Cell-based therapies have been used as promising treatments for several untreatable diseases. However, cellbased therapies have side effects such as tumorigenesis and immune responses. To overcome these side effects, therapeutic effects of exosomes have been researched as replacements for cell-based therapies. In addition, exosomes reduced the risk that can be induced by cell-based therapies. Exosomes contain biomolecules such as proteins, lipids, and nucleic acids that play an essential role in cell–cell and cell–matrix interactions during biological processes. Since the introduction of exosomes, those have been proven perpetually as one of the most effective and therapeutic methods for incurable diseases. Much research has been conducted to enhance the properties of exosomes, including immune regulation, tissue repair, and regeneration. However, yield rate of exosomes is the critical obstacle that should be overcome for practical cell-free therapy. Three-dimensional (3D) culture methods are introduced as a breakthrough to get higher production yields of exosomes. For example, hanging drop and microwell were well known 3D culture methods and easy to use without invasiveness. However, these methods have limitation in mass production of exosomes. Therefore, a scaffold, spinner flask, and fiber bioreactor were introduced for mass production of exosomes isolated from various cell types. Furthermore, exosomes treatments derived from 3D cultured cells showed enhanced cell proliferation, angiogenesis, and immunosuppressive properties. This review provides therapeutic applications of exosomes using 3D culture methods.
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We aimed to develop evidence-based recommendations for treating axial spondylarthritis (axSpA) in Korea. The development committee was constructed, key clinical questions were determined, and the evidence was searched through online databases including MEDLINE, Embase, Cochrane, KoreaMed, and Kmbase. Systematic literature reviews were conducted, quality of evidence was determined, and draft recommendations were formulated according to the Grading of Recommendations Assessment, Development, and Evaluations methodology. Recommendations that reached 80% consensus among a voting panel were finalized. Three principles and 21 recommendations were determined. Recommendations 1 and 2 pertain to treatment strategies, regular disease status assessment, and rheumatologist-steered multidisciplinary management. Recommendations 3 and 4 strongly recommend patient education, exercise, and smoking cessation. Recommendations 5–12 address pharmacological treatment of active disease using nonsteroidal anti-inflammatory drugs, glucocorticoids, sulfasalazine, biologics, and Janus kinase inhibitors. Recommendations 13–16 address treatment in stable disease. We suggest against spa and acupuncture as therapies (Recommendation 17). Recommendations 18 and 19 pertain to total hip arthroplasty and spinal surgery. Monitoring of comorbidities and drug toxicities are recommended (Recommendations 20 and 21). Recommendations for axSpA treatment in a Korean context were developed based on comprehensive clinical questions and evidence. These are intended to guide best practice in the treatment of axSpA.
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Background/Aims@#Some management strategies for acute colonic diverticulitis remain controversial in Korean real-world practice because their clinical features differ from those in the West. This study aimed to investigate the opinions of Korean physicians regarding the diagnosis and treatment of acute diverticulitis. @*Methods@#A web-based survey was conducted among gastroenterologists specializing on treating lower gastrointestinal disorders. The questionnaires concerned overall management strategies for colonic diverticulitis, including diagnosis, treatment, and follow-up. @*Results@#In total, 209 gastroenterologists responded to the survey. Less than one-fourth of the respondents (23.6%) answered that left-sided colonic diverticulitis is more likely to be complicated than right-sided colonic diverticulitis. Most respondents agreed that immunocompromised patients with diverticulitis have worse clinical outcomes than immunocompetent patients (71.3%). Computed tomography was the most preferred tool for diagnosing diverticulitis (93.9%). Approximately 89% of the respondents answered that they believed antibiotic treatment is necessary to treat acute uncomplicated diverticulitis. Most respondents (92.6%) agreed that emergency surgery is not required for diverticulitis with an abscess or microperforation without panperitonitis. Further, 94.7% of the respondents agreed that colon cancer screening is necessary in patients aged ≥ 50 years with diverticulitis after they have recovered from acute illness. Many respondents (71.4%) agreed that surgery for recurrent diverticulitis should be individualized. @*Conclusions@#Opinions regarding management strategies for colonic diverticulitis among Korean gastroenterologists were well agreed upon in some areas but did not agree well in other areas. Evidence-based guidelines that meet the practical needs of the Korean population should be developed.
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Objectives@#This study aimed to assess the contact tracing outcomes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron sub-lineages BA.4, BA.5, and BA.2.75 within Republic of Korea, and to generate foundational data for responding to future novel variants. @*Methods@#We conducted investigations and contact tracing for 79 confirmed BA.4 cases, 396 confirmed BA.5 cases, and 152 confirmed BA.2.75 cases. These cases were identified through random sampling of both domestically confirmed and imported cases, with the goal of evaluating the pattern of occurrence and transmissibility. @*Results@#We detected 79 instances of Omicron sub-lineage BA.4 across a span of 46 days, 396 instances of Omicron sub-lineage BA.5 in 46 days, and 152 instances of Omicron sub-lineage BA.2.75 over 62 days. One patient with severe illness was confirmed among the BA.5 cases; however, there were no reports of severe illness in the confirmed BA.4 and BA.2.75 cases. The secondary attack risk among household contacts were 19.6% for BA.4, 27.8% for BA.5, and 24.3% for BA.2.75. No statistically significant difference was found between the Omicron sub-lineages. @*Conclusion@#BA.2.75 did not demonstrate a higher tendency for transmissibility, disease severity, or secondary attack risk within households when compared to BA.4 and BA.5. We will continue to monitor major SARS-CoV-2 variants, and we plan to enhance the disease control and response systems.
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Objectives@#Coronavirus disease 2019 (COVID-19) has been declared a global pandemic owingto the rapid spread of the causative agent, severe acute respiratory syndrome coronavirus 2.Its Delta and Omicron variants are more transmissible and pathogenic than other variants.Some debates have emerged on the mechanism of variants of concern. In the COVID-19 wave that began in December 2021, the Omicron variant, first reported in South Africa, became identifiable in most cases globally. The aim of this study was to provide data to inform effective responses to the transmission of the Omicron variant. @*Methods@#The Delta variant and the spike protein D614G mutant were compared with the Omicron variant. Viral loads from 5 days after symptom onset were compared usingepidemiological data collected at the time of diagnosis. @*Results@#The Omicron variant exhibited a higher viral load than other variants, resulting in greater transmissibility within 5 days of symptom onset. @*Conclusion@#Future research should focus on vaccine efficacy against the Omicron variant and compare trends in disease severity associated with its high viral load.
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Background@#This study presents a novel technical tip for intraoperative tumor localization and determination of the proximal resection line using a titanium ring strip for totally laparoscopic distal gastrectomy in patients with middle-third gastric cancer and describes the short-term results of its application. @*Methods@#In total, 42 patients with middle-third gastric cancer who underwent intraoperative tumor localization using a titanium ring strip and determination of the proximal resection line through intraoperative radiography between January 2020 and December 2021 were enrolled in this study. We retrospectively analyzed patients’ prospectively collected clinical, pathological, and surgical data. @*Results@#Twenty-six men and 16 women with a mean age of 58.3±12.5 years were enrolled. The mean operation time and estimated blood loss were 212.6±43.0 minutes and 122.4±77.6 mL, respectively. The lengths of the proximal and distal resection margin were 2.0±0.4 cm (range, 0.8–3.7 cm) and 10.5±4.1 cm (range, 0.4–20.4 cm), respectively. Roux-en-Y anastomosis was performed in 30 patients, while Billroth II with Braun anastomosis was performed in 12 patients. There were no procedure-related complications, and the mean postoperative hospital stay was 7.2±1.9 days. For all patients, the negative proximal resection margin was confirmed by postoperative pathological examinations. @*Conclusions@#Intraoperative tumor localization and determination of the proximal resection line using a titanium ring strip is a useful alternative method that can be easily and safely performed. This method is especially useful for patients with middle-third gastric cancer requiring an appropriate proximal resection margin.
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Acute pancreatitis caused by eosinophilic gastroenteritis is a rare disease, and little has been reported so far. Diagnosing eosinophilic gastroenteritis is difficult because the symptoms and laboratory findings are not specific. We report a rare case of eosinophilic gastroenteritis related to acute pancreatitis as a possible cause of idiopathic acute pancreatitis. A 61-year-old man visited the hospital complaining of epigastric pain. Although no pancreatic abnormalities were confirmed on imaging studies, the patient showed hyperamylasemia and hyperlipasemia. Serum eosinophil fractions were initially normal. However, they were elevated on follow-up examinations, and a large number of eosinophils were observed in the biopsies of the stomach and duodenum, which led to the diagnosis of eosinophilic gastroduodenitis related to acute pancreatitis.
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Purpose@#Team-based learning in medical education facilitates the formation of interpersonal relationships, enhances academic achievement, and establishes future clinical connections. Despite medical schools’ distinct educational environments and curricula, research investigating students’ learning and behavioral characteristics within this context remains limited. This study aimed to investigate the specific characteristics of interpersonal relationship formation among freshmen medical students in team-based learning activities. @*Methods@#Focus group interviews were conducted with 11 students who participated in a team-based class held during the first semester of the premedical year. @*Results@#Medical students passively expressed their thoughts and feelings, such as active sympathy for the team’s opinions and self-censorship of SNS (social networking service) conversations. When performing team activities, students were excessively conscious of others and focused on evenly dividing their work, minimizing their opinions, and fulfilling their share to prevent potential interpersonal conflicts. Interpersonal activities were only superficial, as students intentionally maintained a certain distance from team members or used team activities as an opportunity to accumulate relational capital. @*Conclusion@#The results of this study are expected to provide a useful basis for designing and conducting team activity classes to enhance interpersonal relationship formation.
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Objectives@#This study aimed to examine the association between overtime hours and perceived stress, depression, and anxiety among coronavirus disease 2019 (COVID-19) community health workers. @*Methods@#Self-report data were collected from 1,181 community health workers in Busan between 15 June and 2 July 2021. The data collected were analyzed using analysis of variance and logistic regression to examine how average weekly overtime hours affect perceived stress, depression, and anxiety. @*Results@#The proportion of individuals who perceived a high degree of stress was higher in the groups with average weekly overtime of 5-10 hours (odds ratio [OR] 1.81, 95% confidence interval [CI] 1.09-3.01) and 10 or more hours (OR 2.26, 95% CI 1.33-3.82) than in the group with average weekly overtime of less than 5 hours. Among the groups with average weekly overtime of 5-10 hours and 10 or more hours, the proportion of individuals at a high risk of depression was OR 1.74 (95% CI 1.31-2.31) and OR 3.39 (95% CI 2.53-4.54), respectively. In the same two groups, the proportion of individuals at a high risk of anxiety was OR 1.75 (95% CI 1.31-2.33) and OR 3.34 (95% CI 2.51-4.46), respectively. @*Conclusions@#This study shows that perceived stress, depression, and anxiety levels significantly increase as average weekly overtime hours increase among COVID-19 community health workers.
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Purpose@#We investigated the clinical features and risk factors associated with the onset of uveitis in patients with ankylosing spondylitis. @*Methods@#A survey was conducted targeting patients with ankylosing spondylitis who have experienced uveitis. The questionnaire collected information on demographic characteristics, clinical features, and lifestyle-related risk factors for uveitis including stress, sleep quality, rest periods, eating habits, and intake of caffeine, alcohol, and tobacco. Respondents were asked to recall their condition at the time of their most recent uveitis flare-up and rate it on a 5-point scale (1 = good to 5 = bad). @*Results@#The study included 47 patients with ankylosing spondylitis; the average age was 40.0 years, 68.1% were male, and 89.4% tested positive for human leukocyte antigen (HLA)-B27. The average treatment duration for uveitis was 5.2 weeks, with an average recurrence rate of 4.5 times. The most common symptom at the time of uveitis was eye redness (87.2%). The average scores for the surveyed risk factors were as follows: stress, 4.1 points; sleep, 3.1 points; rest, 3.4 points; eating habits, 2.9 points; caffeine intake, 3.3 points; alcohol intake, 2.4 points; and smoking, 2.5 points. No significant correlation was found between age, uveitis treatment duration, number of recurrences, and any of the surveyed scores. @*Conclusions@#Patients with ankylosing spondylitis appeared to experience higher levels of stress during episodes of uveitis; however, further investigation is needed.
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Objectives@#This study investigated causative strains and their antibiotic sensitivity in patients who were hospitalized for maxillofacial odontogenic infections at a tertiary center in South Korea over the past 10 years with the aim of providing guidelines for the selection of appropriate empirical antibiotics. @*Materials and Methods@#Patients with head and neck fascial space abscesses due to odontogenic infections who underwent incision and drainage surgery with pus culture tests between 2013 and 2022 at the Department of Oral and Maxillofacial Surgery, Dankook University Hospital were included. The bacterial isolates and antibiotic sensitivity of each strain were analyzed for 2013-2022, 2013-2017, and 2018-2022. The affected fascial spaces were classified into primary, secondary, and deep neck spaces. @*Results@#In the 192 patients included in this study, 302 strains were detected. Viridans streptococcus had the highest frequency (51.7%), followed by Prevotella spp. (16.9%), Staphylococcus spp. (5.6%), and Klebsiella pneumoniae (4.6%). The identification rate of viridans streptococcus significantly increased from 41.8% in 2013-2017 to 60.9% in 2018-2022. Viridans streptococcus showed an antibiotic sensitivity of 80.5% to ampicillin; the sensitivity to penicillin antibiotics decreased over the study period. Antibiotic susceptibility was approximately 94% for third-generation cephalosporins.K. pneumoniae, which was identified at a high percentage in patients with deep neck space infection, showed increasing antibiotic resistance to most antibiotics over the study period. @*Conclusion@#Viridans streptococcus was identified in head and neck fascial space abscesses with the highest frequency. Empirical antibiotics should be effective against this strain; penicillin antibiotics are considered inappropriate. For effective treatment of deep neck space abscesses, bacterial culture and antibiotic sensitivity tests performed as soon as possible are essential.