ABSTRACT
Purpose@#The purpose of this study was to evaluate whether three-dimensional (3D)-printed flexible denture resin has suitable mechanical properties for use as a thermoplastic denture base resin material. @*Materials and Methods@#A total of 96 specimens were prepared using the 3D printed flexible denture resin (Flexible Denture). Specimens were designed in CAD software (Tinkercad) and printed through a digital light-processing 3D printer (Asiga MAX UV). Post-polymerization process was conducted according to air exposure or glycerin immersion at 35°C or 60°C and for 30 or 60 minutes. The maximum flexural strength, elastic modulus, 0.2% offset yield strength, and Vickers hardness of 3D-printed flexible denture resin were assessed.Result: The maximum flexural strength ranged from 64.46±2.03 to 84.25±4.32 MPa, the 0.2% offset yield strength ranged from 35.28±1.05 to 46.13±2.33 MPa, the elastic modulus ranged from 1,764.70±64.66 to 2,179.16±140.01 MPa, and the Vickers hardness ranged from 7.01±0.40 to 11.45±0.69 kg/mm2 . @*Conclusion@#Within the limits of the present study, the maximum flexural strength, 0.2% offset yield strength, elastic modulus, and Vickers hardness are sufficient for clinical use under the post-polymerization conditions of 60°C at 60 minutes with or without glycerin precipitation.
ABSTRACT
PURPOSE: Long term hospitalized infants in neonatal intensive care units(NICUs) are prone to systemic infection. It is important to differentiate systemic candidiasis from systemic bacterial infection early in the course. Thus, in this study, we have compared clinical characteristics of systemic candidiasis and systemic bacterial infection, in premature low birth weight infants. METHODS: Retrospective chart review of the medical records of 20 patients with systemic candidiasis and 23 patients with systemic bacterial infection was performed. RESULTS: Among the risk factors of systemic candidiasis, total parenteral nutrition(TPN), the use of broad spectrum antibiotics, central catheter insertion, endotracheal intubation and the use of H2 blockers were more frequent in neonates with systemic candidiasis than neonates with systemic bacterial infection. Apnea with bradycardia developed more frequently in neonates with systemic candidiasis compared with systemic bacterial infection(75% vs 39%). In laboratory findings at symptom onset, seven cases(35%) of systemic candidal infections and two cases(9%) of systemic bacterial infections showed leukopenia and thrombocytopenia(P=0.03). Blood was the most frequent isolation site of candida and bacteria. CONCLUSION: In neonates with systemic candidiasis, apnea with bradycardia, pneumonia and thrombocytopenia were prone to develop more frequently. The use of TPN, antibiotics and central catheters was strongly associated with systemic candidiasis. Empirical treatment with antifungal agent should be considered in critically ill neonates with above findings.
Subject(s)
Humans , Infant , Infant, Newborn , Anti-Bacterial Agents , Apnea , Bacteria , Bacterial Infections , Bradycardia , Candida , Candidiasis , Catheters , Critical Illness , Infant, Low Birth Weight , Intensive Care, Neonatal , Intubation, Intratracheal , Leukopenia , Medical Records , Pneumonia , Retrospective Studies , Risk Factors , ThrombocytopeniaABSTRACT
PURPOSE: Tuberculosis may cause a serious complication in children with cancer who are receiving the chemotherapy. But its diagnosis is not easy if we do not suspect the disease in patients with uncontrolled persistent fever. We studied retrospectively the importances of prevention and early diagnosis of tuberculosis in cancer patients. METHPDS: Twelve patients were diagnosed as having tuberculosis during cancer chemotherapy in Kyungpook National University Hospital from May, 1981 to May, 1998. We reviewed their clinical features, diagnostic methods, treatment and prevention. RESULTS: The median age of the patients was 14 (2~18) years. The underlying diseases were seven acute lymphoblastic leukemia (ALL), two acute undifferentiated leukemia (AUL), one acute nonlymphoblastic leukemia (ANLL), one mixed-lineage leukemia, and one Burkitt's lymphoma. The disease categories of tuberculosis were seven pulmonary tuberculosis, two tuberculous pleurisy, one miliary tuberculosis, one bone and endotracheal tuberculosis and one tuberculous meningitis. The family history of tuberculosis is positive in one case. The clues of the suspicion of tuberculosis infections were 9 cases of persistent fever despite broad spectrum of antibiotics and/or antifungal agent therapy, 2 chronic cough and 1 chest pain. We could diagnose four by AFB culture, three cases by AFB smear, two by polymerase chain reaction (PCR), one by pleural biopsy, one by transbronchial lung biopsy and one by chest X-ray and CSF study. We treated pulmonary tuberculosis and tuberculous pleurisy by triple therapy (isoniazid, rifampin, pyrazinamide) and miliary, bone, endotracheal tuberculosis and tuberculous meningitis by quadriple therapy (isoniazid, rifampin, pyrazinamide, streptomycin or kanamycin). The mean duration of defervescence after treatment was 15.4 days. One died of fulminant hepatitis probably by hepatitis B after completion of cancer chemotherapy, one died of adult respiratory distress syndrome, two died of DIC, three died of relapse of underlying disease, but no one died of tuberculosis infection itself. CONCLUSION: The early diagnosis of tuberculosis is an important factor for decreasing the mortality rates of cancer patients, so we should have a suspicion of this disease in patients with persistent fever in spite of appropriate antibiotic and antifungal agents. Isoniazid prophylaxis may be needed in childhood cancer patients with chemotherapy in Korea.