The aim of this study was to compare the initial apical file (IAF) length between the mesio-buccanl and mesio-lingual canals of the mandibular molar before and after early coronal flaring. Fifty mandibular molars with complete apical formation and patent foramens were selected. After establishing the initial working length of the buccal and lingual canal of the mesial root using the Root-ZX, radiographs were taken for the working length with a 0.5 mm short of #15 K-file tip just visible at the foramen under a surgical microscope (OPMI 1-FC, Carl Zeiss Co. Germany) at 25X. After early coronal flaring using the K3 file, additional radiographs were taken using the same procedure. The root canal morphology and the difference in working length between the buccal and lingual canals were evaluated. These results show that the difference in the length between the mesio-buccal and mesio-lingual canals of the mandibular molar was < or = 0.5 mm. If one canal has a correct working length for the mesial root of the mandibular molar, it can be used effectively for measuring the working length of another canal when the files are superimposed or loosening. In addition, the measured the working length after early coronal flaring is much more reasonable because the difference in the length between the mesio-buccal and mesio-lingual canals can be reduced.
Dental Pulp Cavity ; Molar*

Purpose: Following the outbreak and global spread of the coronavirus disease 2019 (COVID-19), an increasing number of people have turned to cycling. This study aims to investigate the epidemiology of bicycle-related injuries before and after the emergence of the COVID-19. Methods: In this retrospective study, we collected medical records of those patients who visited the emergency room for orthopedic injuries related to bicycle accidents. The “COVID-19 period” consisted of the patients identified from April 1 to November 31 in the year 2020, while the “pre-COVID-19 period” consisted of those identified during the same months of the year 2019. Results: A total of 519 patients were identified. The bicycle-related injuries increased by 5.1% during the COVID-19, in comparison to the pre-COVID-19 period. Among these, 76.3% were men. The highest incidence of the injuries was seen for 10– 19 years of age during the pre-COVID-19, and for 50– 59 years of age during the COVID-19 period. Overall, upper limb injuries were the commonest, consisting of 32.2% of all injuries. The shoulder injuries were the commonest in the pre-COVID-19, while the knee injuries were the commonest in the COVID-19 period. Assessing the severity of the injuries, contusion (81.8%) was the commonest. Of the injuries requiring hospital admissions, hip injuries had the highest incidence at 76.5%. Conclusion During the COVID-19, the total number of bicycle-related injuries did not increase significantly. In the bicycle-related injuries, the middle-age group had the highest proportion during the COVID-19 period. More efficient prevention strategies for middle-aged riders are necessary.

Purpose: Following the outbreak and global spread of the coronavirus disease 2019 (COVID-19), an increasing number of people have turned to cycling. This study aims to investigate the epidemiology of bicycle-related injuries before and after the emergence of the COVID-19. Methods: In this retrospective study, we collected medical records of those patients who visited the emergency room for orthopedic injuries related to bicycle accidents. The “COVID-19 period” consisted of the patients identified from April 1 to November 31 in the year 2020, while the “pre-COVID-19 period” consisted of those identified during the same months of the year 2019. Results: A total of 519 patients were identified. The bicycle-related injuries increased by 5.1% during the COVID-19, in comparison to the pre-COVID-19 period. Among these, 76.3% were men. The highest incidence of the injuries was seen for 10– 19 years of age during the pre-COVID-19, and for 50– 59 years of age during the COVID-19 period. Overall, upper limb injuries were the commonest, consisting of 32.2% of all injuries. The shoulder injuries were the commonest in the pre-COVID-19, while the knee injuries were the commonest in the COVID-19 period. Assessing the severity of the injuries, contusion (81.8%) was the commonest. Of the injuries requiring hospital admissions, hip injuries had the highest incidence at 76.5%. Conclusion During the COVID-19, the total number of bicycle-related injuries did not increase significantly. In the bicycle-related injuries, the middle-age group had the highest proportion during the COVID-19 period. More efficient prevention strategies for middle-aged riders are necessary.

PURPOSE: To investigate the improvement in balance after TKA and the difference of balance between posterior cruciate ligament retaining & posterior cruciate ligament substituting prostheses. MATERIALS AND METHODS: Twenty-six patients scheduled to undergo TKA were randomly assigned to receive either PCL-retaining or PCL-substituting prosthesis. The balance of the subjects were checked prior to and at least six months after the operation by computerized dynamic posturography. We investigated whether the balance improve and the difference of change between the implants. RESULTS: Patients showed significantly the improvement of balance by the knee proprioception after TKA (p<0.05) during intercepting visual compensation and the more HSS Knee score improve, the more its balance improve (p<0.05, r=0.667). But the difference of balance between the implants was not detected significantly (p>0.05). CONCLUSION: The balance by the proprioception improves as the HSS Knee Score increases after TKA, and does not show the difference between the implants.
Compensation and Redress ; Humans ; Knee ; Posterior Cruciate Ligament ; Proprioception ; Prostheses and Implants

PURPOSE: We analyzed the correlation of the Lysholm score, anterior displacement of tibia on stress radiography and muscle strength around the knee with postural control after anterior cruciate ligament reconstruction and also compared them with the normal subjects. MATERIALS AND METHODS: Twenty-five patients after ACL reconstruction were evaluated with Lysholm knee score, anterior displacement on stress radiography with Telos, muscle strength around the knee with Biodex dynamometer and postural control with posturography. RESULTS: The postural control had significant correlation with the Lysholm knee score & anterior displacement on stress radiography(r=0.565, r=0.783, p<0.01), but not with muscle strength around the knee(p>0.05). Patients group with 5mm instability under anterior displacement on stress radiography showed no significance compared with normal control group, while the group with instability more than 6mm showed significant differences in some conditions com- pared with control group. CONCLUSION: Postural control after ACL reconstruction have significant correlation with Lysholm score and we presumed that the acquisition of mechanical stability of the knee after ACL reconstruction may be one of the important factors associated with the recovery of postural control by improvement of the proprioception.
Anterior Cruciate Ligament Reconstruction* ; Anterior Cruciate Ligament* ; Humans ; Knee ; Muscle Strength ; Proprioception ; Radiography ; Tibia

Change in tumor volume after chemotherapy appears to have a prognostic significance for the outcome of osteosarcoma. A newly developed volume measurement method based on three-dimensional summation with a proved reproducibility was utilized to measure osteosarcoma tumor volume. This retrospective analysis included 38 patients with biopsy- proven, nonsurface, skeletal high-grade osteosarcoma. The treatment was started by using three cycles of preoperative chemotherapy with cisplastin (100 mg/m2) and adriamycin (30 mg/m2). The tumor volume was measured before and after preoperative chemotherapy using three-dimensional magnetic resonance image measurement. The percentage of tumor necrosis was assessed by pathologic exam. After three cycle of postoperative chemotherapy, the patients were followed up at regular interval. For the 23 good responder patients, the mean survival time was 73.2 months (95% confidence interval 61.9 - 84.5 months), and for the 15 poor responder patients, the mean survival time was 50.8 months (95% confidence interval 38.6 - 63.1 months) (p < 0.05). For the 14 patients with increased tumor volume after chemotherapy, the mean survival time was 47.5 months (range: 36.3 - 58.6 months) and for the 24 patients with stable or decreased tumor volume, the mean survival time was 74.3 months (range: 63.79 - 84.88 months) (p < 0.05). Among the various factors, histopathologic response and tumor volume change after chemotherapy predicted disease free survival (p < 0.05). Change in the tumor volume that was measured with a reproducible method and the histopathologic response after chemotherapy were the important predictors of disease free survival for osteosarcoma patients.
Antibiotics, Antineoplastic/therapeutic use ; Antineoplastic Agents/therapeutic use ; Bone Neoplasms/drug therapy/*mortality/*pathology ; Cisplatin/therapeutic use ; Disease-Free Survival ; Doxorubicin/therapeutic use ; Humans ; Osteosarcoma/drug therapy/*mortality/*pathology ; Predictive Value of Tests ; Prognosis ; Retrospective Studies

An intramural hematoma of the stomach usually results from trauma. Gastric intramural hematomas may also occur in patients with bleeding disorders who are receiving anticoagulation therapy or after an endoscopic procedure. Here, we describe a case of a gastric intramural hematoma after endoscopic hemostasis for gastric ulcer bleeding in a patient medicated with aspirin.
Aspirin ; Epinephrine ; Hematoma ; Hemorrhage ; Hemostasis, Endoscopic ; Humans ; Stomach ; Stomach Ulcer