1.An experimental study on the bond stregth of etched cast restoration using different metal surface treatments.
The Journal of Korean Academy of Prosthodontics 1991;29(1):13-22
No abstract available.
2.Dislodgement resistance of modified resin-bonded fixed partial dentures utilizing tooth undercuts: an in vitro study.
The Journal of Advanced Prosthodontics 2009;1(2):85-90
STATEMENT OF PROBLEM: Over the years, resin-bonded fixed partial dentures (RBFPDs) have gone through substantial development and refinement. Several studies examined the biomechanics of tooth preparation and framework design in relation to the success rate of RBFPDs and considered retention and resistance form essential for increase of clinical retention. However, these criteria required preparations to be more invasive, which violates not only the original intentions of the RBFPD, but may also have an adverse effect on retention due to loss of enamel, an important factor in bonding. PURPOSE: The object of this in vitro study was to compare the dislodgement resistance of the new types of RBFPDs, the conventional three-unit fixed partial denture, and conventional design of RBFPD (Maryland bridge). MATERIAL AND METHODS: Fifty resin mandibular left second premolars and second molars were prepared on dentiforms, according to the RBFPD design. After model fabrication (five group, n = 10), prostheses were fabricated and cemented with zinc phosphate cement. After cementation, the specimens were subjected to tensile loading at a cross head speed of 4 mm/min in a universal testing machine. The separation load was recorded and analyzed statistically using one-way analysis of variance followed by Duncan's multiple range test. RESULTS: Group V, the pin-retained RBFPDs, had the highest mean dislodgement resistance, whereas specimens of group II, the conventional RBFPDs, exhibited a significantly lower mean dislodgement resistance compared to the other 4 groups (P < .05). There were no significant differences between group I, III, and IV in terms of dislodgement resistance (P > .05). Group V had the highest mean MPa (N/mm2) (P < .05). There was no significant difference between groups I, II, III and IV (P > .05). CONCLUSION: Within the limits of the design of this in vitro study, it was concluded that: 1. The modified RBFPDs which utilizes the original tooth undercuts and requires no tooth preparation, compared with the conventional design of RBFPDs, has significantly high dislodgement resistance (P < .05). 2. The modified RBFPDs which utilizes the original tooth undercuts and requires minimal tooth preparation, compared with the conventional FPDs, has significantly no difference in retention and dislodgement resistance)(P > .05). 3. The pin-retained FPDs showed a high dislodgement resistance compared to the conventional three-unit FPDs (P < .05).
Bicuspid
;
Biomechanics
;
Cementation
;
Collodion
;
Dental Enamel
;
Denture, Partial, Fixed
;
Head
;
Intention
;
Molar
;
Phosphates
;
Prostheses and Implants
;
Retention (Psychology)
;
Tooth
;
Tooth Preparation
;
Zinc Compounds
;
Zinc Phosphate Cement
3.Alternative impression technique for multiple abutments in difficult case to control.
Bock Young JUNG ; Keun Woo LEE
The Journal of Advanced Prosthodontics 2010;2(1):1-3
BACKGROUND: Even though excellent impression materials are now available for making accurate replication for hard and soft tissue, the numerous dentists have faced lots of obstacles in making simultaneous impressions of multiple abutments. CASE DESCRIPTION: This article describes a modified method of tray fabrication using auto-polymerizing acrylic resin and impression technique for multiple prepared teeth in cases with limitations and difficulties in taking dental impressions. CLINICAL IMPLICATION: This segmental tray technique has several advantages, including higher impression quality, fewer impressions, and being more comfortable for the patient and less stressful for the clinician.
Dentists
;
Humans
;
Tooth
6.Statistical Analysis of Serologic test for Syphilis Durinf five Years.
Keun Woo LEE ; Chong Ju LEE ; Chin Yo CHANG
Korean Journal of Dermatology 1979;17(6):441-450
This paper is studied for statistical anaIysis of 1181 cascs of positive V.D.R.L test among 24414 cases who were visited for annual Physical examination and in or outpatients in the Han Gang Sung Shim Hospital during 5 years and 7 months from January 1972 to July 1977. Clinical survey was carried out with 182 syphilitic patients in the Department of Dermatology, Han Gang Sung Shim Hospital during 19 months from January l976 to July 1977. The results were as follows; 1. Positive rate for V.D.R.L test was 4.8%, and there were statistically significant differences in annual incidence(P<0.01). Biologic false positive rate for V.D.R.L test was 26. 7%, and there were statistically aignificant differences in annual incidence(P<0.01). 2. Departmental analysis such as Dermatology, Urology, Physical Examination and others including Obstetrics and Gynecology, Internal Medicine, Pediatrics etc. were carried out, the results showed that there were statistically significant departmental differences in V.D.R.L positive rate, but no in biologic false positive rate. 3. Biologic false positive rate was high inversely proportional to dilution titer, and that was a statistically significant difference(P<0.01). 4. 182 had syphilis, of whom 106(58. 2%) were latent syphilis and 74(40. 7%) were primary and secondary syphilis. 5. 119(65. 4%) among 182 syphilitic patients were male, most of patients(87.8%) occured in age from 21 to 40 years in the both sex. But there no statistically significant differences in age distribution between males and females. 6. The most predilection site of chancre was coronary sulcus(54.5%). 7. The lesions of secondary syphilis were composed of 18 cases(25%) of condyloma latum, 17 cases(23. 6%) of roseolar syphilid, 17 cases of papulo-squamous syphilid, 13 cases of alopecia syphilitica, 1 case of pustular syphilid, and 6 cases of others. 8. Married patients were nearly two times than single. In women, married. patients were much more(80. 3%) than single, and there were statistically significatnt differences(P<0.01). 9. There were no significant differences in S.T.S positive rate of spouse between infectious and latent syphilis. 10. Occupation distribution of male sexual partners were composed of 35 cases(29. 4%) of waitress, 28 cases(23. 5%) of call-girl, 20 cases(16. 8%) of office-girl, 17 cases of housewife, 12 cases of out of work, 7 cases of student. 1I. For patients with primary, secondary, and latent syphilis, treatment consiste of benzathine penicillin 2. 4 million units intramuscularly on the first visit and repeated three penicillin preparations at 7 days intervals in most of patients.
Age Distribution
;
Alopecia
;
Chancre
;
Dermatology
;
Female
;
Gynecology
;
Humans
;
Internal Medicine
;
Male
;
Obstetrics
;
Occupations
;
Outpatients
;
Pediatrics
;
Penicillin G Benzathine
;
Penicillins
;
Physical Examination
;
Serologic Tests*
;
Sexual Partners
;
Spouses
;
Syphilis*
;
Syphilis, Cutaneous
;
Syphilis, Latent
;
Urology
8.The Effect of Hemostatic Solution on Dentin Permeability.
Chang Hyun KIM ; Jung Sung SHIM ; Keun Woo LEE
The Journal of Korean Academy of Prosthodontics 2000;38(4):472-483
Before impression making in the fixed restorations or other prosthesis, hemostatic solutions are used for hemostasis and moisture control. Hemostatic solutions effectively control bleeding but their major ingredients, acid removes smear layers which are formed in the tooth preparation, exposes the dentinal tubular orifices which are occluded by smear layers, makes dentinal tubular fluid displace more easily to the various external stimulus, and according to the hydrodynamic theory, consequently causes dentin hypersensitivity. To know the effect of hemostatic solutions on dentin permeability, coronal dentin discs, 1 mm in thickness, were prepared from extracted third molars free from decay and wear, and a spilt chamber device was used. Hydraulic conductance values and SEMs, which were measured before and after treatment with Astringedentr , Altract and Epri-dent , were compared and analyzed. The following conclusion were drawn : 1. Hydraulic conductance values which wee measured after the treatment of hemostatic solutions were increased in all groups(p<0.05). 2. %change values of hydraulic conductance were compared but no significant difference was found among the three hemostatic solutions(p<0.05). 3. on SEM observations of all groups, after treatment smear layers were removed and dentinal tubular orifices were partially exposed. on the basis of these conclusions, the reckless use of hemostatic solutions should be restricted, and when in use, various methods should be considered to protect dentin.
Dentin Permeability*
;
Dentin Sensitivity
;
Dentin*
;
Hemorrhage
;
Hemostasis
;
Hydrodynamics
;
Molar, Third
;
Prostheses and Implants
;
Tooth Preparation
10.Laparoscopic Transperitoneal Adrenalectomy : Clinical Experinece with 18 Cases.
Woo Keun LEE ; Tae Gyun KWON ; Yoon Kyu PARK
Korean Journal of Urology 2000;41(12):1471-1476
No abstract available.
Adrenalectomy*