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1.
Journal of Korean Academy of Conservative Dentistry ; : 211-221, 2010.
Article in English | WPRIM | ID: wpr-58040

ABSTRACT

Proteoglycan is highly hydrophilic and negatively charged which enable them attract the water. The objective of study was to investigate the effects of Proteoglycan on microtensile bond strength of dentin adhesives and on architecture of dentin collagen matrix of acid etched dentin by removing the chondroitin sulphate attached on Proteoglycan. A flat dentin surface in mid-coronal portion of tooth was prepared. After acid etching, half of the specimens were immersed in 0.1 U/mL chondroitinase ABC (C-ABC) for 48 h at 37degrees C, while the other half were stored in distilled water. Specimens were bonded with the dentin adhesive using three different bonding techniques (wet, dry and re-wet) followed by microtensile bond strength test. SEM examination was done with debonded specimen, resin-dentin interface and acid-etched dentin surface with/without C-ABC treatment. For the subgroups using wet-bonding or dry-bonding technique, microtensile bond strength showed no significant difference after C-ABC treatment (p > 0.05). Nevertheless, the subgroup using rewetting technique after air dry in the Single Bond 2 group demonstrated a significant decrease of microtensile bond strength after C-ABC treatment. Collagen architecture is loosely packed and some fibrils are aggregated together and relatively collapsed compared with normal acid-etched wet dentin after C-ABC treatment. Further studies are necessary for the contribution to the collagen architecture of noncollagenous protein under the various clinical situations and several dentin conditioners and are also needed about long-term effect on bond strength of dentin adhesive.


Subject(s)
Adhesives , Bisphenol A-Glycidyl Methacrylate , Chondroitin , Chondroitin ABC Lyase , Chondroitin Sulfates , Collagen , Dentin , Proteoglycans , Tooth , Water
2.
Journal of the Korean Association of Maxillofacial Plastic and Reconstructive Surgeons ; : 425-428, 2009.
Article in Korean | WPRIM | ID: wpr-784916
3.
Journal of Korean Academy of Conservative Dentistry ; : 148-161, 2008.
Article in Korean | WPRIM | ID: wpr-105056

ABSTRACT

The purpose of this study was to evaluate the effect of chlorhexidine (CHX) on microtensile bond strength (microTBS) of dentin bonding systems. Dentin collagenolytic and gelatinolytic activities can be suppressed by protease inhibitors, indicating that MMPs (Matrix metalloproteinases) inhibition could be beneficial in the preservation of hybrid layers. Chlorhexidine (CHX) is known as an inhibitor of MMPs activity in vitro. The experiment was proceeded as follows: At first, flat occlusal surfaces were prepared on mid-coronal dentin of extracted third molars. GI (Glass Ionomer) group was treated with dentin conditioner, and then, applied with 2% CHX. Both SM (Scotchbond Multipurpose) and SB (Single Bond) group were applied with CHX after acid-etched with 37% phosphoric acid. TS (Clearfil Tri-S) group was applied with CHX, and then, with adhesives. Hybrid composite Z-250 and resin-modified glass ionomer Fuji-II LC was built up on experimental dentin surfaces. Half of them were subjected to 10,000 thermocycle, while the others were tested immediately. With the resulting data, statistically two-way ANOVA was performed to assess the microTBS before and after thermocycling and the effect of CHX. All statistical tests were carried out at the 95% level of confidence. The failure mode of the testing samples was observed under a scanning electron microscopy (SEM). Within limited results, the results of this study were as follows; 1. In all experimental groups applied with 2% chlorhexidine, the microtensile bond strength increased, and thermocycling decreased the microtensile bond strength (P > 0.05). 2. Compared to the thermocycling groups without chlorhexidine, those with both thermocycling and chlorhexidine showed higher microtensile bond strength, and there was significant difference especially in GI and TS groups. 3. SEM analysis of failure mode distribution revealed the adhesive failure at hybrid layer in most of the specimen, and the shift of the failure site from bottom to top of the hybrid layer with chlorhexidine groups. 2% chlorhexidine application after acid-etching proved to preserve the durability of the hybrid layer and microtensile bond strength of dentin bonding systems.


Subject(s)
Acrylic Resins , Adhesives , Chimera , Chlorhexidine , Dentin , Glass , Matrix Metalloproteinases , Microscopy, Electron, Scanning , Molar, Third , Phosphoric Acids , Protease Inhibitors , Silicon Dioxide
4.
Journal of the Korean Association of Maxillofacial Plastic and Reconstructive Surgeons ; : 370-379, 2008.
Article in Korean | WPRIM | ID: wpr-784831
5.
Journal of Korean Academy of Conservative Dentistry ; : 343-355, 2007.
Article in Korean | WPRIM | ID: wpr-175705

ABSTRACT

The objectives of this study was to evaluate the durability of 4 resin cements by means of microtensile bond strength test combined with thermocycling method and fractographic FE-SEM analysis. Experimental groups were prepared according to thermocycling (0, 1,000, 5,000) and the kind of resin cements, those were Variolink II, Multilink, Panavia F 2.0, Rely X Unicem. Flat dentin surfaces were created on mid-coronal dentin of extracted third molars. Then fresh dentin surface was grounded with 320-grit silicon carbide abrasive papers to create uniform smear layers. Indirect composite block (Tescera, Bisco Inc., Schaumburg, IL, USA) was fabricated (12 x 12 x 6 mm3). It's surface for bonding to tooth was grounded with silicon carbide abrasive papers from 180- to 600-grit serially, then sandblasted with 20 - 50 microm alumina oxide. According to each manufacturer's instruction, dentin surface was treated and indirect composite block was luted on it using each resin cement. For Rely X Unicem, dentin surface was not treated. The bonded tooth-resin block were stored in distilled water at 37degrees C for 24 hours. After thermocycling, the bonded tooth-resin block was sectioned occluso-gingivally to 1.0 mm thick serial slabs using an Isomet slow-speed saw (Isomet, Buehler Ltd, Lake Bluff, IL, USA). These sectioned slabs were further sectioned to 1.0 x 1.0 mm2 composite-dentin beams. The specimens were tested with universal testing machine (EZ-Test, Shimadzu, Japan) at a crosshead speed of 1.0 mm/min with maximum load of 500 N. The data was analyzed using one-way ANOVA and Duncan's multiple comparison test at p 0.05). 4. Adhesive based-resin cements showed lower bond strength with or without thermocycling than composite based-resin cements. 5. Variolink II & Multilink showed high bond strength and mixed failure, which was occurred with a thin layer of luting resin cement before thermocycling and gradually increased adhesive failure along the dentin surface after thermocycling. The bonding performance of resin cement can be affected by application procedure and chemical composition. Composite based-resin cement showed higher bond strength and durability than adhesive based-resin cement.


Subject(s)
Adhesives , Aluminum Oxide , Dentin , Lakes , Molar, Third , Resin Cements , Tooth , Water
6.
Journal of Korean Academy of Conservative Dentistry ; : 222-235, 2007.
Article in Korean | WPRIM | ID: wpr-140575

ABSTRACT

The objectives of this study was to evaluate the effect of thermocycling on the microTBS (microtensile bond strength) to dentin with four different adhesive systems to examine the bonding durability. Freshly extracted 3rd molar teeth were exposed occlusal dentin surfaces, and randomly distributed into 8 adhesive groups: 3-steps total-etching (Scotchbond Multi-Purpose Plus; SM, All Bond-2; AB), 2-steps total-etching (Single Bond; SB, One Step plus; OS), 2-steps self-etching (Clearfil SE Bond; SE, AdheSE; AD) and single-step self-etching systems (Promp L-Pop; PL, Xeno III; XE). Each adhesive system in 8 adhesives groups was applied on prepared dentin surface as an instruction and resin composite (Z250) was placed incrementally and light-cured. The bonded specimens were sectioned with low-speed diamond saw to obtain 1 x 1 mm sticks after 24 hours of storage at 37degrees C distilled water and proceeded thermocycling at the pre-determined cycles of 0, 1,000 and 2,000. The microTBS test was carried out with EZ-tester at 1 mm/min. The results of bond strength test were statistically analyzed using one-way ANOVA/Duncan's test at the alpha < 0.05 confidence level. Also, the fracture mode of debonded surface and the interface were examined under SEM. The results of this study were as follows; 1. 3-step total etching adhesives showed stable, but bond strength of 2-step adhesives were decreased as thermocycling stress. 2. SE showed the highest bond strength, but single step adhesives (PL, XE) had the lowest value both before and after thermocycling. 3. Most of adhesives showed adhesive failure. The total-etching systems were prone to adhesive failure and the single-step systems were mixed failure after thermocycling. Within limited results of this study, the bond strength of adhesive system was material specific and the bonding durability was affected by the bonding step/procedure of adhesive. Simplified bonding procedures do not necessarily imply improved bonding performance.


Subject(s)
Adhesives , Dentin , Diamond , Molar , Tooth , Water
7.
Journal of Korean Academy of Conservative Dentistry ; : 222-235, 2007.
Article in Korean | WPRIM | ID: wpr-140574

ABSTRACT

The objectives of this study was to evaluate the effect of thermocycling on the microTBS (microtensile bond strength) to dentin with four different adhesive systems to examine the bonding durability. Freshly extracted 3rd molar teeth were exposed occlusal dentin surfaces, and randomly distributed into 8 adhesive groups: 3-steps total-etching (Scotchbond Multi-Purpose Plus; SM, All Bond-2; AB), 2-steps total-etching (Single Bond; SB, One Step plus; OS), 2-steps self-etching (Clearfil SE Bond; SE, AdheSE; AD) and single-step self-etching systems (Promp L-Pop; PL, Xeno III; XE). Each adhesive system in 8 adhesives groups was applied on prepared dentin surface as an instruction and resin composite (Z250) was placed incrementally and light-cured. The bonded specimens were sectioned with low-speed diamond saw to obtain 1 x 1 mm sticks after 24 hours of storage at 37degrees C distilled water and proceeded thermocycling at the pre-determined cycles of 0, 1,000 and 2,000. The microTBS test was carried out with EZ-tester at 1 mm/min. The results of bond strength test were statistically analyzed using one-way ANOVA/Duncan's test at the alpha < 0.05 confidence level. Also, the fracture mode of debonded surface and the interface were examined under SEM. The results of this study were as follows; 1. 3-step total etching adhesives showed stable, but bond strength of 2-step adhesives were decreased as thermocycling stress. 2. SE showed the highest bond strength, but single step adhesives (PL, XE) had the lowest value both before and after thermocycling. 3. Most of adhesives showed adhesive failure. The total-etching systems were prone to adhesive failure and the single-step systems were mixed failure after thermocycling. Within limited results of this study, the bond strength of adhesive system was material specific and the bonding durability was affected by the bonding step/procedure of adhesive. Simplified bonding procedures do not necessarily imply improved bonding performance.


Subject(s)
Adhesives , Dentin , Diamond , Molar , Tooth , Water
8.
Journal of Korean Epilepsy Society ; : 53-56, 2002.
Article in Korean | WPRIM | ID: wpr-174111

ABSTRACT

Neuronal ceroid lipofuscinoses (NCL) are the most common childhood neurodegenerative disorders. Clinical features include seizures, blindness, psychomotor deterioration, the age of onset differ for each NCL type. Diagnosis of late infantile NCL relies on the characteristic clinical presentation, electrophysiological and neuroradiological findings, and identification of the ultrastructural abnormalities. The Photoparoxsmal response provide diagnostic clues to an atypical case of Infantile NCL in which results of extraneuronal biopsies were negative and MRI findings resembles leukodystrophy. Photic stimulation with 2 to 5 Hz activity elicited discrete spike and wave discharges in the occipital region on electroencephalogram and no sleep spindles are present. In patients with rapid neurologic deterioration, diagnosis of NCL should be considered and an EEG must be performed using photic stimulation to look for characteristic findings.


Subject(s)
Humans , Age of Onset , Biopsy , Blindness , Diagnosis , Electroencephalography , Magnetic Resonance Imaging , Neurodegenerative Diseases , Neuronal Ceroid-Lipofuscinoses , Photic Stimulation , Seizures
9.
The Korean Journal of Thoracic and Cardiovascular Surgery ; : 528-530, 2000.
Article in Korean | WPRIM | ID: wpr-123602

ABSTRACT

Thoracoscopic sympathectomy is a common technique used to treat plamar hyperhiodrosis. The complications of thoracoscopic sympathectomy are rare. Recently, we experienced a complex regional pain syndrome(CRPS) after thoracoscopic sympathecotomy in a patient with hyperhidrosis. The treatment of this complication was chemical epidural sympathetic block and conservative pain control. The result of this treatment was good. The patient was recovered after one month.


Subject(s)
Humans , Hyperhidrosis , Pain, Postoperative , Sympathectomy , Thoracoscopy
10.
Korean Journal of Nephrology ; : 756-759, 2000.
Article in Korean | WPRIM | ID: wpr-73546

ABSTRACT

Subclavian and internal jugular vein catheters are widely employed for temporary hemodialysis access. Placement of subclavian venous catheter has many complications such as pneumothorax and hemothorax, etc. Incidence of subclavian vein obstruction due to thrombosis is probably greater than is commonly appreciated. Subclavian vein obstruction may cause no specific complaints, but thrombosis in the presence of an arteriovenous fistula may produce severe symptoms such as massive edema and pain. This is report of one patient, who developed massive edema of upper extremity and in whom proximal subclavian vein occlusion developed after previous percutaneous dialysis catheter. Right internal jugular vein to axillary vein bypass with 8mm PTFE provided prompt and effective venous outflow, with complete resolution of venous engorgement of the affected limb and preservation of the dialysis fistula.


Subject(s)
Humans , Arteriovenous Fistula , Axillary Vein , Catheters , Dialysis , Edema , Extremities , Fistula , Hemothorax , Hyperemia , Incidence , Jugular Veins , Pneumothorax , Polytetrafluoroethylene , Renal Dialysis , Subclavian Vein , Thrombosis , Upper Extremity
11.
Korean Journal of Infectious Diseases ; : 252-255, 2000.
Article in Korean | WPRIM | ID: wpr-101104

ABSTRACT

Pichia ohmeri is a very rare pathogen of human infection. To date, two cases of P. ohmeri infection were reported worldwide. We have experienced a case of catheter-related P. ohmeri fungemia. The patient had been admitted due to cerebrovascular accident in rehabilitation center since August 1998. He had been bedridden due to previous cerebrovascular accident and undergone several episodes of nosocomial infection. Multiple antimicrobial agents had been used with central venous catheter for parenteral nutrition. On February 1999, he had developed fever and dyspnea. Vancomycin and imipenem were administered empirically and central venous catheter was removed on the impression of central venous catheter related infection. Blood culture and catheter tip culture grew P. ohmeri. He developed septic shock and finally led to death before the administration of amphotericin B.


Subject(s)
Humans , Amphotericin B , Anti-Infective Agents , Catheters , Central Venous Catheters , Cross Infection , Dyspnea , Fever , Fungemia , Imipenem , Parenteral Nutrition , Pichia , Rehabilitation Centers , Shock, Septic , Stroke , Vancomycin
12.
Korean Journal of Orthodontics ; : 21-33, 1997.
Article in Korean | WPRIM | ID: wpr-647959

ABSTRACT

The purpose of this study was to investigate the factors affecting the postsurgical mandibular stability for both one- and two-jaw surgery. 18 for one-jaw surgerys and 24 for two-jaw surgerys among skeletal class III malocclusion patients who experienced orthodontic treatment and orthognathic surgery at Pusan National University Hospital were selected Lateral cephalograms taken at the first visit, after presurgical orthodontic treatment, immediately after surgery and follow-up over 6 months, were traced. Based ANOVA, multiple linear regression analysis was completed for one-jaw surgery with postsurgical stability as the criterion and the magnitude of mandibular setback, the change of mandibular incisor height during surgery, the changes of mandibular plane angle and mandibular incisor angle during presurgical orthodontic treatment as affecting factors. Same analysis was completed for two-jaw surgery with postsurgical stability as the criterion and the-magnitude of mandibular setback as affecting factor. The results were as follows: 1. In the one-jaw surgery cases, the magnitude of mandibular setback the change of mandibular incisor height during surgery, the changes of mandibular plane angle and mandibular incisor angle during presurgical orthodontic treatment explained the variability in postsurgical stability with a significant R2 value of 0.84. 2. In the two jaw surgery cases, the magnitude of mandibular setback explained the variability in postsurgical stability with a significant R2 value of 0.28.


Subject(s)
Humans , Follow-Up Studies , Incisor , Linear Models , Malocclusion , Orthognathic Surgery
13.
Korean Journal of Preventive Medicine ; : 791-804, 1997.
Article in Korean | WPRIM | ID: wpr-124121

ABSTRACT

Irritable bowel syndrome(IBS) is one of the common health problem that has been considered as stress-induced. This study was conducted to investigate the relationship between life style and the level of stress and IBS by structured questionnaire which included questions on life style, the self-esteemed gastrointestinal symptoms, and Psychosocial Well-being Index(PWI). Subjects were 1,498 male white collars who get the regular health check and participated in survey at Inje University Health Promotion Center from January to December, 1996. The overall prevalence of IBS was 37.5%(561 cases), and the level of stress by PWI score was higher in IBS group(41.8+/-14.2) than symptom-free group(34.6+/-12.6). As the result of comparison between the two groups, heavier smoking (adjusted OR=2.48, 95% CI 1.81-3.41), longer daily working time (adjusted OR=5.19, 95% CI 3.59-7.56), stimulatory food materials-mainly hot or salty (adjusted OR=1.87, 95% CI 1.44-2.45), higher body mass index (adjusted OR=1.80, 95% CI 1.27-2.57), and higher level of stress (adjusted OR=2.81, 95% CI 1.80-4.43) were estimated as risk factors of IBS. On the contrary, 6-8 hours sleeping per day (adjusted OR=0.38 95% CI 0.21-0.70), 3-4 times exercise per week (adjusted OR=0.57 95% CI 0.39-0.83), and tenure more than 20 years (adjusted OR=0.25 95% CI 0.16-0.35) were considered as protective factors to IBS. In summary, the assessment of the stress level might be placed in the first priority to control IBS, at least by some degree, which suggested that IBS could be controlled by avoiding such risk factors and by encouraging such protective factors.


Subject(s)
Humans , Male , Body Mass Index , Health Promotion , Irritable Bowel Syndrome , Life Style , Prevalence , Surveys and Questionnaires , Risk Factors , Smoke , Smoking
14.
Korean Journal of Preventive Medicine ; : 765-784, 1996.
Article in Korean | WPRIM | ID: wpr-24824

ABSTRACT

This study surveyed and measured the level and structure of cancer deaths and their trends over time for offering the fundamental data of the cancer prevention and control in Pusan city in the future. Authors conducted the study of descriptive epidemiology using materials derived from the computerized data of total 3,722 certified cancer deaths in Pusan city from January 1 to December 31, 1993 registered on the National Statistical Office, the Republic of Korea. The obtained results were as follows: 1. According to the total registered cases of deaths(16,331 cases) in Pusan city during 1993, cancer(3,722 cases) and cerebrovascular disease(2,718 cases) were the first and second cause of deaths as 23.1% and 16.9%, respectively. These pattern showed the change between cancer(14.7%) and cerebrovascular disease(18.5%) in order of frequency in comparison to 1982. Also, the total number of cancer deaths was increased in comparison to 1982. The rate of death certification by physicians was 87.1% of all registered deaths, which was increased to 6.8% in comparison to 1982(80.3%). 2. Crude death rate and cancer specific death rate was 4.06 per 1,000 populations and 93.8 per 100,000 populations(male:117.8, female:70.0), respectively. The former was similar to that of 1982, but the latter was increased to 1.6 times as that of 1982. 3. Age-adjusted cancer specific death rate by standardization with whole country population was 111.9(male:141.5, female:106.7) per 100,000 populations, higher than not age-adjusted cancer specific death rate(93.8), and the sex difference was statistically significant with male predominance(p<0.05). 4. Cancer specific death rate by age was generally increased with age and most of cancer deaths(male:91.8%, female:88.5%) occurred since 40 years old. 5. The major cancer(cancer specific death rate per 100,000 populations) in male was liver(30.6) followed by stomach(25.6), lung(21.9), and GB and EHBD(5.7), in female stomach(15.7), liver(9.9), lung(7.3), and uterus(6.9). The relative frequency of the leading three cancer among total cancer deaths marked 66.3% in male and 47.1% in female, and decreased in comparison to 1982(male:72.2%, female:54.5%). 6. The total ratio of male to female cancer specific death rate showed 1.68 to 1 with male predominance. And the ratio was above 2.0 in larynx, oral cavity & pharynx, esophagus, liver, lung, bladder cancer and the ratio was 1.0~1.9 in stomach, pancreas, gall bladder and EHBD, brain, rectum and anus cancer, leukemia, but the ratio was reversed in thyroid and colon cancer. In conclusion, cancer was the first cause of deaths. The proportion of lung cancer was increased, that of stomach & uterine cancer was decreased relatively, and liver cancer was constantly higher proportion. In the future, it is necessary to conduct the further investigations on the cancer risk factors considering areal specificity.


Subject(s)
Adult , Female , Humans , Male , Anus Neoplasms , Brain , Cause of Death , Certification , Colonic Neoplasms , Epidemiologic Studies , Epidemiology , Esophagus , Larynx , Leukemia , Liver , Liver Neoplasms , Lung , Lung Neoplasms , Mortality , Mouth , Pancreas , Pharynx , Rectum , Republic of Korea , Risk Factors , Sensitivity and Specificity , Sex Characteristics , Stomach , Thyroid Gland , Urinary Bladder , Urinary Bladder Neoplasms , Uterine Neoplasms
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