• Title/Summary/Keyword: 결론

Search Result 22,353, Processing Time 0.055 seconds

Study about the clinical features and Pulmonary function Tst of Endobronchial Tuberculosis (기관지결핵의 임상상 및 폐기능검사에 관한 연구)

  • Chung, Hee-Soon;Lee, Jae-Ho
    • Tuberculosis and Respiratory Diseases
    • /
    • v.43 no.2
    • /
    • pp.147-158
    • /
    • 1996
  • Background : Endobronchial tuberculosis(ET) is known to affect frequently young female and serious complication like bronchial stenosis would occur if early diagnosis and treatment for ET is not performed immediately. But ET shows normal chest roentgenogram in about 10% of patients, and is often confused with bronchial asthma because ET presents clinical features like cough, dyspnea, wheezing in history and physical examination. The pulmonary function test(PFT) feature of ET is not well known, but when we consider the fact that ET is pathophysiologically different from bronchial asthma, if there is any feature of PFT in ET, and we know it, PFT will be very helpful for diagnosis and follow up of ET. Methods : We performed both PFT and bronchoscopy in 68 ET patients who visited Boramae hospital, and were confirmed as ET by bronchoscopic biopsy and were followed prospectively from November 1991 to March 1995. After history taking and physical examination, we performed chest roentgenogram, complete blood count, sputum AFB stain and culture, and also performed PFT before anti-tuberculosis chemotherapy. PFT was classified as restrictive, if only PVC was reduced below 80%, and obstructive, if only FEV1 was reduced below 75%. In the case of both FVC and FEV1 were reduced, PFT was classified as restrictive if FEY1/FVC was greater than 75%, and mixed if FEV1/FVC was reduced below 75%. We repeated the PFT and bronchoscopy for 68 ET patients who were proven by biopsy in the first month and sixth month after starting anti-tuberculosis chemotherapy, and studied the feature and change of PFT of the ET and the relation between PFT and the bronchoscopic finding, and obtained following results. Results: 1) Number of male patients was 12, and that of female patient was 56, and mean age was $35.4{\pm}17yr$.(17-74yr). Clinical symptom was in the order of cough(86.8%), dyspnea(63.2%), fever(17.6%) and hemoptysis (10.3%), and the wheezing and stridor were audible among the 40 patients(58.4%) in the physical examination. 2) Hemoglobin level was below 12g/dl among 25 patients (36.8%), and WBC level was above $10,000/mm^3$ among 9 patients(13.2%) and ESR was above 20 among 46 patients (67.6%) and AFB stain and culture were positive among 50 patients(73.5%). 3) The dominant roentgenographic finding of ET was fibronodular feature in 35 patients(51.5%), pneumonic feature in 14 patients (20.6%), collapse in 11 patients(16.2%), mass-like lesion in 3 patients(4.4%), cavitary lesion in 2 patients(2.9%), and normal in 3 patients(4.4%). 4) PFT feature at the time of diagnosis of ET was normal in 16 patients(23.5%), restrictive pattern in 32 patients (47%), obstructive in 4 patients(5.8%), and mixed in 14 patients(23.5%). So restrictive pattern was the dominate feature of ET. 5) The PFT feature was little correlated with the gross finding of bronchoscopy, but the change of PFT during treatment of ET showed relatively good correlation with the change of bronchoscopic finding. 6) FVC(2.30L vs. 2.61L) and FEV1(1.74L vs. 2.06L) increased significantly (p < 0.01), but FEV1/FVC(82% vs. 83%) and PEF(3.45L/sec vs. 3.95L/sec) did not change significantly after 1 month of treatment (p > 0.01), and there was no significant change among all parameters during first and sixth month of treatment(p > 0.01). Conclusion : PFT may be useful in the diagnosis and treatment follow up of ET but further study would be needed to confirm it.

  • PDF

Comparision of Chest Radiographs and Pulmonary Function in Coal Workers' Pneumoconiosis and Welders' Lung (탄광부 진폐증과 용접공 폐증에 있어 흉부-X선 소견과 폐기능의 비교)

  • Park, Dong-Youl;Hwang, Joo-Ho;Kang, Byung-Son;Chung, Chan-Su;Kim, Wha-Jo
    • Tuberculosis and Respiratory Diseases
    • /
    • v.42 no.5
    • /
    • pp.713-722
    • /
    • 1995
  • Background: Chest X-ray of coal workers' pneumoconiosis and shipyard welders' lung show similar and regular opacities mostly, it is very difficult that we distinguish the former from the latter by only chest X-ray. so we performed this study to understand the progression of the disease and to provide the disease by considering pulmonary function and other factors in proportion to the profusion of small regular opacities of chest X-ray in both groups. Method: 430 coal workers' pneumoconiosis were compared with 311 shipyard welders' lung by the number, the age, the duration of dust exposure, %vital capacity(%VC), %FEV1.0, the type of ventilatory impairment, the combined pulmonary disease according to the profusion of small regular opacities on the chest radiographs, which were classified into category 0/1, category 1, and category 2. Result: 1) the percent of category 2 in coal workers' pneumoconiosis was 54.4%. the percent of category 1, and category 2 in welders' lung were 60.0%, 7.4%. the progression to the category 2 was higher in coal workers' pneumoconiosis than in welders' lung 2) The mean age was higher in coal workers' pneumoconiosis than in welders' lung, significantly increased in proportion to the progresion of profusion of small regular opacities in both groups 3) There was no difference in the duration of dust exposure by category 1/0, but the duration of dust exposure by category 1, 2 in coal workers' pneumoconiosis more significantly increased than in welders' lung. the duration in the proportion of category 2 to category 0/1, 1 significantly increased in the proportion to small regular opacities in coal workers' pneumoconiosis. but there was no significant difference in the proportion to small regular opacities in duration of dust exposure in welders' lung. 4) There was no significant difference of mean values of %VC(%vital capacity)in both groups except for category 1. the mean values of %VC had no relationship between the progression of small regular opacities in both groups. 5) The mean values of %FEV1.0 decreased more significantly in coal workers' pneumoconiosis than in welders' lung except for category 0/1. and decreased significantly in proportion to the profusion of small regular opacities in coal workers' pneumoconiosis. there was significant difference of %FEV1.0 in the proportion of category 2 to category 011 in welders' lung. 6) there were no significant difference of %FEV1.0, %VC in smoker and nonsmoker in both groups. 7) With regard to the type of ventilation in both groups in coal workers' pneumoconiosis 21.4 percent of patients belonged to the restrictive type, 11.6 percent to the obstructive type, 5.6 percent to the combined type, but in welders' lung 21.8 percent to the restrictive type, 2.9 percent to the obstructive type, 1.9 percent to the combined type. 8. in the pulmonary disease, the incidence of the pulmonary tuberculosis was the most in both groups, was more in coal workers' pneumoconiosis than welders' lung Conclusion: If we compare coal workers' pneumoconiosis with electric arc welders'lung by considering pulmonary function and other factors in proportion to the profusion of chest X-ray, I think that we will have the better result in understanding the progression of the disease and provision of the disease in both groups.

  • PDF

Human Parathyroid Hormone-Related Peptide Measurement in the Lung Cancer Patients (폐암환자에서 인체 부갑상선 호르몬 관련 단백에 대한 연구)

  • Chang, Joon;Kim, Se-Kyu;Lim, Sung-Kil;Lee, Hong-Lyeol;Kim, Sung-Kyu;Lee, Won-Young
    • Tuberculosis and Respiratory Diseases
    • /
    • v.42 no.6
    • /
    • pp.855-861
    • /
    • 1995
  • Background: Parathyroid hormone-related protein(PTHrp) was first identified as the cause of hypercalcemia in malignancy. Hypercalcemia can be found in malignancy, especially in the epidermoid carcinoma of the lung, even without extensive metastases to the bones. The application of sensitive assays for PTHrp may help in the early diagnosis of lung cancer, in the monitoring of treatment and in the detection of recurrence. Method: Serum PTHrp was measured by radioimmunoassay detecting the N-terminal 1~34 peptide of human PTHrp(PTHrp 1-34) in 63 histologically confirmed lung cancer patients and 22 healthy controls. Result: Serum PTHrp(mean$\pm$S.E.) was $312{\pm}68.9pg/ml$ in 63 lung cancer patients and $158{\pm}38.2pg/ml$ in 22 controls(p>0.05). PTHrp was $356{\pm}103.9pg/ml$ in 34 epidermoid carcinoma patients, $281{\pm}148.7pg/ml$ in 15 adenocarcinoma patients and $316{\pm}140.8pg/ml$ in 9 small cell carcinoma patients. In epidermoid carcinoma patients, PTHrp was $570{\pm}472.3pg/ml$ in stage II(n=3; p<0.05 vs controls), $166{\pm}22.4pg/ml$ in stage IIIa(n=9), $282{\pm}113.3pg/ml$ in stage IIIb(n=12) and $668{\pm}367.9pg/ml$ in stage IV(n=9; p<0.05 vs controls). PTHrp was significantly increased in 8 epidermoid carcinoma patients with bone metastases($1526{\pm}811.2\;pg/ml$; p<0.0005 vs controls). Hypercalcemia was observed in an epidermoid carcinoma patient whose PTHrp value was 244 pg/ml. Conclusion: The serum PTHrp was increased in advanced epidermoid carcinoma patients even without hypercalcemia. The measurement of PTHrp may be not helpful in the early diagnosis of lung cancer. But the lung cancer should be suspected in the marked elevation of PTHrp. It may be of value in detecting patients of advanced diseases with bone metastases or patients who might develop the malignancy associated hypercalcemia.

  • PDF

Role of Oxygen Free Radical in the Expression of Interleukin-8 and Interleukin-$1{\beta}$ Gene in Mononuclear Phagocytic Cells (내독소에 의한 말초혈액 단핵구의 IL-8 및 IL-$1{\beta}$ 유전자 발현에서 산소기 역할에 관한 연구)

  • Kang, Min-Jong;Kim, Jae-Yeol;Park, Jae-Seok;Lee, Seung-Joon;Yoo, Chul-Gyu;Kim, Young-Whan;Han, Sung-Koo;Shim, Young-Soo
    • Tuberculosis and Respiratory Diseases
    • /
    • v.42 no.6
    • /
    • pp.862-870
    • /
    • 1995
  • Background: Oxygen free radicals have generally been considered as cytotoxic agents. On the other hand, recent results suggest that small nontoxic amounts of these radicals may act a role in intracellular signal transduction pathway and many efforts to reveal the role of these radicals as secondary messengers have been made. It is evident that the oxygen radicals are released by various cell types in response to extracellular stimuli including LPS, TNF, IL-1 and phorbol esters, all of which translocate the transcription factor $NF{\kappa}B$ from cytoplasm to nucleus by releasing an inhibitory protein subunit, $I{\kappa}B$. Activation of $NF{\kappa}B$ is mimicked by exposure to mild oxidant stress, and inhibited by agents that remove oxygen radicals. It means the cytoplasmic form of the inducible tanscription factor $NF{\kappa}B$ might provide a physiologically important target for oxygen radicals. At the same time, it is well known that LPS induces the release of oxygen radicals in neutrophil with the activation of $NF{\kappa}B$. From above facts, we can assume the expression of IL-8 and IL-$1{\beta}$ gene by LPS stimulation may occur through the activation of $NF{\kappa}B$, which is mediated through the release of $I{\kappa}B$ by increasing amounts of oxygen radicals. But definitive evidence is lacking about the role of oxygen free radicals in the expression of IL-8 and IL-$1{\beta}$ gene in mononuclear phagocytic cells. We conducted a study to determine whether oxygen radicals act a role in the expression of IL-8 and IL-$1{\beta}$ gene in mononuclear phagocytic cells. Method: Human peripheral blood monocytes were isolated from healthy volunteers. Time and dose relationship of $H_2O_2$-induced IL-8 and IL-$1{\beta}$ mRNA expression was observed by Northern blot analysis. To evaluate the role of oxygen radicals in the expression of IL-8 and IL-$1{\beta}$ mRNA by LPS stimulation, pretreatment of various antioxiants including PDTC, TMTU, NAC, ME, Desferrioxamine were done and Northern blot analysis for IL-8 and IL-$1{\beta}$ mRNA was performed. Results: In PBMC, dose and time dependent expression of IL-8 and IL-$1{\beta}$ mRNA by exogenous $H_2O_2$ was not observed. But various antioxidants suppressed the expression of LPS-induced IL-8 and IL-$1{\beta}$ mRNA expression of PBMC and the suppressive activity was most prominant when the pretreatment was done with TMTU. Conclusion: Oxygen free radical may have some role in the expression of IL-8 and IL-$1{\beta}$ mRNA of PBMC but that radical might not be $H_2O_2$.

  • PDF

The Influence of Aging on Pulmonary Function Tests in Elderly Korean Population (한국에서 노화에 따른 폐기능지표의 변화양상)

  • Lee, Jae-Myung;Kim, Eun-Jung;Kang, Min-Jong;Son, Jee-Woong;Lee, Seung-Joon;Kim, Dong-Gyu;Park, Myung-Jae;Lee, Myung-Goo;Hyun, In-Gyu;Jung, Ki-Suck
    • Tuberculosis and Respiratory Diseases
    • /
    • v.49 no.6
    • /
    • pp.752-759
    • /
    • 2000
  • Background : Many studies have shown that pulmonary function differs widely among race, age and geographical residency. By virtue of the improvement of nutrition and environment, the elderly population in Korea is markedly increasing and so are the ages of patients complaining respiratory symptoms. However, we do not have our own data on the pulmonary functional reserve of elderly persons in Korea. We evaluate the deterioration of pulmonary functional reserve and standardize the predictive values of pulmonary function in the elderly population. Method : Pulmonary function tests were conducted in 100 men and 100 women over the age of 65. We analyzed changes of FVC and $FEV_1$ according to age and height by linear regression. We compared our new multiple linear regression equation with other equations currently used in Korea. Results : In men, the mean age was $71.5{\pm}5.2$(mean${\pm}$SD) years and the mean height was $163.6{\pm}6.2$cm. The mean FVC was $3.42{\pm}0.49{\ell}$ and the mean $FEV_1, $2.72{\pm}v$. In women, the mean age was $72.0{\pm}5.1$ years and the mean height was $149.1{\pm}5.9$cm. The mean FVC was $2.22{\pm}0.42{\ell}$ and the mean $FEV_1$ $1.83{\pm}0.34{\ell}$. Multiple linear regression equation using age and height as an independent factors was as follows : FVC(${\ell}$)=1.857-0.0356$\times$age(year)+0.02517$\times$height(cm) (p<0.01, $R^2$=0.279), $FEV_1(${\ell}$)=1.340-0.02698$\times$age(year)+0.02021$\times$height(cm) (p<0.01, $R^2$=0.255) in men, FVC(${\ell}$) =-0.09765-0.03332$\times$age(year)+0.03164$\times$height(cm) (p<0.01, $R^2$=0.435), $FEV_1(${\ell}$)=-0.l69-0.02469$\times$age(year)+0.02539$\times$height(cm) (p<0.01, $R^2$=0.41) in women. Conclusion : We established prediction regressions for pulmonary functional tests in the elderly Korean population. We also confirmed that currently adopted equations do not exactly anticipate the expected pulmonary functional reserve in the aged person over 65 years old. We suggest that our new equations from this study should be applied to interpret the pulmonary function tests in the elderly population in Korea.

  • PDF

A Multicenter, Randomized, Open, Comparative Study for the Efficacy and Safety of Oral Moxifloxacin 400 mg Once a Day and Clarithromycin 500 mg Twice Daily in Korean Patients with Acute Exacerbations of Chronic Bronchitis (한국인의 만성 기관지염의 급성 악화 환자를 대상으로 한 Moxifloxacin 400mg 1 일 1회 요법과 Clarithromycin 500mg 1일 2회 요법의 치료효과 및 안전성 비교)

  • Kim, Seung-Joon;Kim, Seok-Chan;Lee, Sook-Young;Yoon, Hyeong-Kyu;Kim, Tae-Yon;Kim, Young-Kyoon;Song, Jeong-Sup;Park, Sung-Hak;Kim, Ho-Joong;Chung, Man-Pyo;Suh, Gee-Young;Kwon, O-Jung;Lee, Shin -Hyung;Kang, Kyung-Ho;Lee, Eh-Hyung;Hwang, Sung-Chul;Han, Myung-Ho
    • Tuberculosis and Respiratory Diseases
    • /
    • v.49 no.6
    • /
    • pp.740-751
    • /
    • 2000
  • Background : Moxifloxacin is a newly developed drug which is more potent and safe compared to previous fluoroquinolones. This drug effectively eradicates organisms such as beta-lactamase-producing or other resistant bacteria. Moxifloxacin is known to be effective in treating respiratory infections such as Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Chlamydia pneumoniaeme, Legionella spp. and Mycoplasma pneumoniae. Methods : In a multicenter, randomized, open, comparative study, the efficacy and safety of oral moxifloxacin taken 400 mg once a day and clarithromycin taken 500 mg twice daily for 7 days were compared for the treatment of Korean patients with acute exacerbations of chronic bronchitis. Results : A total of 170 patients were enrolled, and they were divided into two groups: 87 in the moxifloxacin group and 83 in the clarithromycin group. Of those enrolled, 76 (35 for bacteriologic efficacy) in the moxifloxacin group and 77 (31 for bacteriologic efficacy) in the clarithromycin group were included in the efficacy analysis. All were included in the safety analysis. Clinical success was noted in 70 (92.1%) of 76 moxifloxacin-treated patients and 71 (92.2%) of 77 clarithromycin-treated patients. Bacteriologic success rate seemed to be higher in moxifloxacin group (73.5%) than in clarithromycin group (54.8%), but statistically insignificant (p=0.098). Drug susceptibility among organisms initially isolated was higher in moxifloxacin group on Streptococcus pneumoniae, Pseudomonas aeruginosa, Klebsiella pneumoniae (p<0.001). Adverse events were reported by 12.8% of 86 patients receiving moxifloxacin and 21.7% of 83 patients receiving clarithromycin. Headache (4.7% vs 4.8%, moxifloxacin group vs clarithromycin group, respectively) and indigestion (2.3% vs 6.0%, moxifloxacin group vs clarithromycin group, respectively) were the most frequent side effects in the two groups. Conclusion : This study demonstrated that for the treatment of acute exacerbations of chronic bronchitis a 7-day course of moxifloxacin 400 mg od was clinically equivalent and microbiologically superior to clarithromycin 500 mg bid.

  • PDF

Triptolide-induced Transrepression of IL-8 NF-${\kappa}B$ in Lung Epithelial Cells (폐상피세포에서 Triptolide에 의한 NF-${\kappa}B$ 의존성 IL-8 유전자 전사활성 억제기전)

  • Jee, Young-Koo;Kim, Yoon-Seup;Yun, Se-Young;Kim, Yong-Ho;Choi, Eun-Kyoung;Park, Jae-Seuk;Kim, Keu-Youl;Chea, Gi-Nam;Kwak, Sahng-June;Lee, Kye-Young
    • Tuberculosis and Respiratory Diseases
    • /
    • v.50 no.1
    • /
    • pp.52-66
    • /
    • 2001
  • Background : NF-${\kappa}B$ is the most important transcriptional factor in IL-8 gene expression. Triptolide is a new compound that recently has been shown to inhibit NF-${\kappa}B$ activation. The purpose of this study is to investigate how triptolide inhibits NF-${\kappa}B$-dependent IL-8 gene transcription in lung epithelial cells and to pilot the potential for the clinical application of triptolide in inflammatory lung diseases. Methods : A549 cells were used and triptolide was provided from Pharmagenesis Company (Palo Alto, CA). In order to examine NF-${\kappa}B$-dependent IL-8 transcriptional activity, we established stable A549 IL-8-NF-${\kappa}B$-luc. cells and performed luciferase assays. IL-8 gene expression was measured by RT-PCR and ELISA. A Western blot was done for the study of $I{\kappa}B{\alpha}$ degradation and an electromobility shift assay was done to analyze NF-${\kappa}B$ DNA binding. p65 specific transactivation was analyzed by a cotransfection study using a Gal4-p65 fusion protein expression system. To investigate the involvement of transcriptional coactivators, we perfomed a transfection study with CBP and SRC-1 expression vectors. Results : We observed that triptolide significantly suppresses NF-${\kappa}B$-dependent IL-8 transcriptional activity induced by IL-$1{\beta}$ and PMA. RT-PCR showed that triptolide represses both IL-$1{\beta}$ and PMA-induced IL-8 mRNA expression and ELISA confirmed this triptolide-mediated IL-8 suppression at the protein level. However, triptolide did not affect $I{\kappa}B{\alpha}$ degradation and NF-$_{\kappa}B$ DNA binding. In a p65-specific transactivation study, triptolide significantly suppressed Gal4-p65T Al and Gal4-p65T A2 activity suggesting that triptolide inhibits NF-${\kappa}B$ activation by inhibiting p65 transactivation. However, this triptolide-mediated inhibition of p65 transactivation was not rescued by the overexpression of CBP or SRC-1, thereby excluding the role of transcriptional coactivators. Conclusions : Triptolide is a new compound that inhibits NF-${\kappa}B$-dependent IL-8 transcriptional activation by inhibiting p65 transactivation, but not by an $I{\kappa}B{\alpha}$-dependent mechanism. This suggests that triptolide may have a therapeutic potential for inflammatory lung diseases.

  • PDF

The Effects of Autologous Blood Pleurodesis in the Pneumothorax with Persistent Air Leak (지속성 기흉에서 자가혈액을 이용한 흉막유착술의 효과)

  • Yoon, Su-Mi;Shin, Sung-Joon;Kim, Young-Chan;Shon, Jang-Won;Yang, Seok-Chul;Yoon, Ho-Joo;Shin, Dong-Ho;Chung, Won-Sang;Park, Sung-Soo
    • Tuberculosis and Respiratory Diseases
    • /
    • v.49 no.6
    • /
    • pp.724-732
    • /
    • 2000
  • Background : In patients with severe chronic lung diseases even a small pneumothorax can result in life-threatening respiratory distress. It is important to treat the attack by chest tube drainage until the lung expands. Pneumothorax with a persistent air leak that does not resolve under prolonged tube thoracostomy suction is usually treated by open operation to excise or oversew a bulla or cluster of blebs to stop the air leak. Pleurodesis by the instillation of chemical agents is used for the patient who has persistent air leak and is not good candidate for surgical treatment. When the primary trial of pleurodesis with common agent fails, it is uncertain which agent should be used f or stopping the air leak by pleurodesis. It is well known that inappropriate drainage of hemothorax results in severe pleural adhesion and thickening. Based on this idea, some reports described a successful treatment with autologous blood instillation for pneumothorax patients with or without residual pleural space. We tried pleurodesis with autologous bood for pneumothorax with persistent air leak and then we evaluated the efficacy and safety. Methods : Fifteen patients who had persistent air leak in the pneumothorax complicated from the severe chronic lung disease were enrolled. They were not good candidates for surgical treatment and doxycycline pleurodesis failed to stop up their air leaks. We used a mixture of autologous blood and 50% dextrose for pleurodesis. Effect and complications were assessed by clinical out∞me, chest radiography and pulmonary function tests. Results : The mean duration of air leak was 18.4${\pm}$6.16 days before ABP (autologous blood and dextrose pleurodesis) and $5.2{\pm}1.68$ days after ABP. The mean severity of pain was $2.3{\pm}0.70$ for DP(doxycycline pleurodesis) and $1.7{\pm}0.59$ for ABDP (p<0.05). There was no other complication except mild fever. Pleural adhesion grade was a mean of $0.6{\pm}0.63$. The mean dyspnea scale was $1.7{\pm}0.46$ before pneumothrax and $2.0{\pm}0.59$ after ABDP (p>0.05). The mean $FEV_1$ was $1.47{\pm}1.01$ before pneumothorax and $1.44{\pm}1.00$ after ABDP (p>0.05). Except in 1 patient, 14 patients had no recurrent pneumothorax. Conclusion : Autologous blood pleurodesis (ABP) was successful for treatment of persistent air leak in the pneumothorax. It was easy and inexpensive and involved less pain than doxycycline pleurodesis. It did not cause complications and severe pleural adhesion. We report that ABP can be considered as a useful treatment for persistent air leak in the pneumothorax complicated from the severe chronic lung disease.

  • PDF

A comparative study on the correlation between Korean foods and the fractures of PFG and all ceramic crowns for posterior applications (구치용 도재소부금관과 전부도재관에 파절을 일으키는 한국음식에 관한 연구)

  • Kim, Jeong-Ho;Lee, Jai-Bong
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.47 no.2
    • /
    • pp.156-163
    • /
    • 2009
  • Statement of problem: Recently, there have been increased esthetic needs for posterior dental restorations. The failure of posterior dental ceramic restoration are possible not only by the characters of the component materials but also by the type of food. Purpose: The research aim was to compare the in vitro fracture resistance of simulated first molar crowns fabricated using 4 dental ceramic systems, full-porcelain-occlusal-surfaced PFG, half-porcelain-occlusal-surfaced PFG, Empress 2, Ice Zirkon and selected Korean foods. Material and methods: Eighty axisymmetric crowns of each system were fabricated to fit a preparation with 1.5- to 2.0-mm occlusal reduction. The center of the occlusal surface on each of 15 specimens per ceramic system was axially loaded to fracture in a Instron 4465, and the maximum load(N) was recorded. Afterwards, selected Korean foods specimens(boiled crab, boiled chicken with bone, boiled beef rib, dried squid, dried anchovy, round candy, walnut shell) were prepared. 15 specimens per each food were placed under the Instron and the maximum fracture loads for them were recorded. The 95% confidence intervals of the characteristic failure load were compared between dental ceramic systems and Korean foods. Afterwards, on the basis of previous results, 14Hz cyclic load was applied on the 4 systems of dental ceramic restorations in MTS. The reults were analyzed by analysis of variance and Post Hoc tests. Results: 95% confidence intervals for mean of fracture load 1. full porcelain occlusal surfaced PFG Crown: 2599.3 to 2809.1 N 2. half porcelain occlusal surfaced PFG Crown: 3689.4 to 3819.8 N 3. Ice Zirkon Crown: 1501.2 to 1867.9 N 4. Empress 2 Crown: 803.2 to 1188.5 N 5. boiled crab: 294.1 to 367.9 N 6. boiled chicken with bone: 357.1 to 408.6 N 7. boiled beef rib: 4077.7 to 4356.0 N 8. dried squid: 147.5 to 190.5 N 9. dried anchovy: 35.6 to 46.5 N 10. round candy: 1900.5 to 2615.8 N 11. walnut shell: 85.7 to 373.1 N under cyclic load(14Hz) in MTS, fracture load and masticatory cycles are: 1. full porcelain occlusal surfaced PFG Crown fractured at 95% confidence intervals of 4796.8-9321.2 cycles under 2224.8 N(round candy)load, no fracture under smaller loads. 2. half porcelain occlusal surfaced PFG Crown fractured at 95% confidence intervals of 881705.1-1143565.7 cycles under 2224.8 N(round candy). no fracture under smaller loads. 3. Ice Zirkon Crown fractured at 95% confidence intervlas of 979993.0-1145773.4 cycles under 382.9 N(boiled chicken with bone). no fracture under smaller loads. 4. Empress 2 Crown fractured at 95% confidence intervals of 564.1-954.7 cycles under 382.9 N(boiled chicken with bone). no fracture under smaller loads. Conclusion: There was a significant difference in fracture resistance between experimental groups. Under single load, Korean foods than can cause fracture to the dental ceramic restorations are boiled beef rib and round candy. Even if there is no fracture under single load, cyclic dynamic load can fracture dental posterior ceramic crowns. Experimental data with 14 Hz dynamic cyclic load are obtained as follows. 1. PFG crown(full porcelain occlusion) was failed after mean 0.03 years under fracture load for round candy(2224.8 N). 2. PFG crown(half porcelain occlusion) was failed after mean 4.1 years under fracture load for round candy(2224.8 N). 3. Ice Zirkon crown was failed after mean 4.3 years under fracture load for boiled chicken with bone(382.9 N). 4. Empress 2 crown was failed after mean 0.003 years under fracture load for boiled chicken with bone(382.9 N).

Changes of the surface roughness depending on immersion time and powder/liquid ratio of various tissue conditioners (수종의 조직 양화재의 침수시간과 분액비에 따른 표면 거칠기의 변화)

  • Kim, Kyung-Soo;Moon, Hong-Suk;Shim, June-Sung;Jung, Moon-Kyu
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.47 no.2
    • /
    • pp.108-118
    • /
    • 2009
  • Statement of problem: Volume stability, microstructure reproducibility and fluidity along with compatibility with dental stone must be in consideration in order to use tissue conditioner as a material for functional impression. There are few studies concerning the influence of time factor in oral condition on surface roughness of the stone and optimal retention period in the oral cavity considering such changes in surface roughness. Purpose: The purpose of this study was to find out the influence of various kinds of tissue conditioner, its powder/liquid ratio and immersion time on surface roughness of the stone. Material and methods: Materials used in this study were the three kinds of tissue conditioners(Coe-Comfort, Visco-Gel, Soft-Liner) and were grouped into three: group R-mixed with standard powder/liquid ratio that was recommended by the manufacturers, group M-mixed with 20% more powder, group L-mixed with 20% less powder. Specimens were made with the size of 20 mm diameter and 2 mm width. Each tissue conditioner specimens were subdivided into 5 groups according to the immersion time(0 hour, 1 day, 3 days, 5 days, 7 days), completely immersed into artificial saliva and were stored under $37^{\circ}C$. Specimens of which the given immersion time elapsed were taken out and were poured with improved stone, making the stone specimens. Surface roughness of the stone specimens was measured by a profilometer. Results: Within the limitation of this study, the following results were drawn. 1. Major influencing factor on surface roughness of the stone model made from tissue conditioner was the retention period(contribution ratio($\rho$)=62.86%, P<.05) of the tissue conditioner in oral cavity to make functional impression. 2. In case of Coe-Comfort, higher mean surface roughness value of the stone model with statistical significance was observed compared to that of Soft-Liner and Visco-Gel as immersion time changes(P<.05). 3. In case of group L(less), higher mean surface roughness value of the stone model with statistical significance was observed compared to that of R(recommended) and M(more) group as immersion time changes(P<.05). Conclusion: We may conclude that as the retention period of time in oral cavity influences surface roughness of the stone model the most and as the kind of tissue conditioner and its P/L ratio may influence also, clinician should well understand the optimal retention period in oral cavity and choose the right tissue conditioner for the functional impression, thus making the functional impression with tissue conditioner usefully.