Accurate impression is very important to achieve desirable prosthesis and there are many factors in taking a good impression. For example, types of impression material, types of impression tray, impression taking methods and so on. Recently individual tooth tray technique is accepted as obtaining good impression that can be applied to multiple abutment impression, heavy salivated patient, to minimize the effect of natural teeth' s undercuts and to reduce pain during cord packing procedures. The purpose of this study was to compare the accuracy according to materials and forms of the individual tooth tray which is clinically applied nowadays. Used materials in experiment were divided into 3 types (acrylic resin, Futar' occlusion, Blu-mousse) and forms were divided into 2 types (forming occlusal vent hole or not and forming marginal vent space or not). Stone master model from impression body and metal master model were measured by X-PLAN360d to compare occlusal surface discrepancy and marginal discrepancy. The results were as follows 1. In comparison of occlusal surface discrepancy and marginal discrepancy according to materials, groups with three materials showed no statistical difference. 2. In comparison of occlusal surface discrepancy and marginal discrepancy according to occlusal vent hole, groups with occlusal vent hole showed significantly less marginal discrepancy than groups with no occlusal vent hole(p<0.05). 3. In comparison of occlusal surface discrepancy and marginal discrepancy according to 0.5mm marginal-vent-space, groups with no 0.5mm-marginal-vent-space showed significantly less mar ginal discrepancy than groups with 0.5mm-marginal-vent-space(p<0.05). In summary, these results suggest that individual tooth tray made of 3 types of materials with occlusal vent hole and individual tooth tray made of acrylic resin with no marginal vent space showed good accuracy of impression. In addition, individual tooth tray which is made of bite registration materials may be more useful because of advantage in facility and timesaving aspect of fabrication.
Humans ; Jaw Relation Record ; Prostheses and Implants ; Tooth*

Accurate impression is very important to achieve desirable prosthesis and there are many factors in taking a good impression. For example, types of impression material, types of impression tray, impression taking methods and so on. Recently individual tooth tray technique is accepted as obtaining good impression that can be applied to multiple abutment impression, heavy salivated patient, to minimize the effect of natural teeth' s undercuts and to reduce pain during cord packing procedures. The purpose of this study was to compare the accuracy according to materials and forms of the individual tooth tray which is clinically applied nowadays. Used materials in experiment were divided into 3 types (acrylic resin, Futar' occlusion, Blu-mousse) and forms were divided into 2 types (forming occlusal vent hole or not and forming marginal vent space or not). Stone master model from impression body and metal master model were measured by X-PLAN360d to compare occlusal surface discrepancy and marginal discrepancy. The results were as follows 1. In comparison of occlusal surface discrepancy and marginal discrepancy according to materials, groups with three materials showed no statistical difference. 2. In comparison of occlusal surface discrepancy and marginal discrepancy according to occlusal vent hole, groups with occlusal vent hole showed significantly less marginal discrepancy than groups with no occlusal vent hole(p<0.05). 3. In comparison of occlusal surface discrepancy and marginal discrepancy according to 0.5mm marginal-vent-space, groups with no 0.5mm-marginal-vent-space showed significantly less mar ginal discrepancy than groups with 0.5mm-marginal-vent-space(p<0.05). In summary, these results suggest that individual tooth tray made of 3 types of materials with occlusal vent hole and individual tooth tray made of acrylic resin with no marginal vent space showed good accuracy of impression. In addition, individual tooth tray which is made of bite registration materials may be more useful because of advantage in facility and timesaving aspect of fabrication.
Humans ; Jaw Relation Record ; Prostheses and Implants ; Tooth*

Accurate reproduction of intraoral tissue is essential in the fabrication of fixed prosthesis. This selection of impression material and method is very important. In this study, vinyl polysiloxane type impression material Panasil was used. Three impression methods ; one-step technique, individual tray technique, and individual tooth tray technique using the vinyl polysiloxane type bite registration material Futar Occlusion, were used to take horizontal and vertical impression. Improved stone models were fabricated. The amount of occlusal surface discrepaneies, interabutment distance discrepancies, amount of marginal defect were evaluated with the X-PLAN360d and photoscanning. The results were as follows. 1. There was no significant difference in occlusal surface according to the directions and techniques of impression taking. 2. There was no significant difference in interabutment distance discrepancies according to the directions and techniques of impression taking 3. There was no significant difference in marginal discrepancies according to the direction of impression taking but there was significant difference between one-step technique and individual tray technique, individual tooth tray technique (P<0.05). Taken together, these results suggest that individual tray technique and individual tooth tray technique are more accurate for impression taking than one-step technique.
Jaw Relation Record ; Prostheses and Implants ; Reproduction ; Siloxanes ; Tooth

The color change of maxillofacial silicone has been attributed to certain environmental factors such as exposure to the UV component of natural sunlight, wetting and drying of the elastomer, and surface abrasion resulting from the application and removal of cosmetics. The purpose of this study was to evaluate the color change of maxillofacial silicone (Silastic MDX4-4210) according to type of pigment (cadmium yellow, titanium white, cosmetic red), and UV absorber application method after 200, 400, and 600 hours of 350nm UV light irradiation. The results were as follows. 1. According to type of pigments, after 200 hours cosmetic red showed significantly larger color change than cadmium yellow and titanium white, and after 400 and 600 hours color change significantly decreased in the order of cosmetic red, cadmium yellow, and titanium white (p<0.05). 2. In the cadmium yellow group, after 200 hours, the non-treatment group showed significantly larger color change, but after 400 and 600hours, color change significantly decreased in the order of non-treatment, surface application and mixed group (p<0.05). 3. In the titanium white group, there was no significant color change difference between the three groups after 200 and 400 hours, but after 600 hours, the mixed group showed significantly smaller color change than the non-treatment and surface application groups (p<0.05). 4. In the cosmetic red group, there was significant decrease in color change in the order non-treatment, surface application and mixed group (p<0.05). From the results above, the effect of UV light absorber differed according to the type of pigment, but mixing UV light aborber with maxillofacial silicone is thought to give superior resistance against UV light irradiation in the long run.
Cadmium ; Elastomers ; Silicones* ; Sunlight ; Titanium ; Ultraviolet Rays*

Relining and rebasing are essential for long-term success and oral health in removable prosthodontics. Major features of failures between metal base and relining resins are adhesive failure due to lack of chemical bonding. The purpose of this study was to find a better metal primer and metal surface treatment method that enhance the bonding strength with relining resin materials. The surfaces of ticonium alloys were treated with 25micrometer sandblasting (Group A), stone wheel (Group B), stone wheel and EZ oxisor (Group C), 75micrometer sandblasting (Group D) and EZ oxisor application after 75micrometer sandblasting (Group E). They were subdivided into no primer application (Group I), MR bond application (Group II) and Metafast bonding liner (Group III). Then specimens were completed though being bonded with relining resins. The specimens were stored in 38degrees C water for 48 hours and tensile strength was measured using the universal testing machine. The results were as follows, 1. Primer application groups showed higher bond strength than no primer application group(p<0.05). 2. In comparison with primer application groups, MR bond group showed higher bond strength than Meta fast bonding liner application group(p<0.05). 3. In comparison with surface treatment methods. Bond strengths of group A and B were significantly different with group C, D, and E, and group C were significantly different with group D, and E in no primer application group(p<0.05). In primer application groups, group A, B, C were significantly different with group D and E(p<0.05). According to results of this study, Metal primer application and metal surface roughening were considered to be advantageous for relining of metal base dentures.
Adhesives ; Alloys ; Denture Bases* ; Dentures* ; Oral Health ; Prosthodontics ; Tensile Strength* ; Water

Dental porcelain should have adequate strength and similar esthetics as natural teeth. Recently esthetics has become a high priority in clinical dentistry. Thus the evaluation of color stability of dental porcelain has become an important part in dental research. The purpose of this study was to evaluate the difference in color stability of 3 types of porcelain (Vintage, VMK 95, CERAMCO II). The porcelain were divided into groups by 2 types of treatment (Glazing or non-glazing and thermocycling or non-thermocycling). The porcelain wee dyed with methylene blue and distilled water, and then the color stability was evaluated with a spectrophotometer. The results were as follow ; 1. The color change of porcelain increased in the order of VMK 95, Vintage, CERAMCO II. But there was no significant difference. 2. The color change decreased in the glazing group compared to the non-glazing group(p<0.05). 3. The color change increased after thermocycling But there was no significant difference. 4. The color change according to dye method was significantly larger with methylene blue copared to distilled water(P<0.05).
Crowns* ; Dental Porcelain* ; Dental Research ; Dentistry ; Esthetics ; Methylene Blue ; Tooth ; Water

A fundamental principle in clasp selection for a specific abutment is the reduction of the transmission of excessive forces to the abutment tooth. Those forces include tilting, tipping, and stress on the abutment tooth. The flexibility of a clasp was believed to directly affect the reduction of such forces. Opinions have been expressed concerning the proper type of clasp to be used to prevent stress on periodontium. In order to evaluate and compare the various designs of a clasp system, it is necessary to measure these force. This study compared the average measurements of forces required to dislodge three kinds of circumferential clasps having different amount of undercuts : the first with a round retentive arm, the second with a half round retentive arm, the third with a wrought wire retentive arm under tensile load. Three commonly used undercuts( 0.01, 0.02, 0.03 inch) were created on nine cast crowns, premolars and molars. The test was run six times for a same clasp. The means of tensile load required to dislodge each of the different clasps were compared statistically using the ANOVA test and multiple range test (Duncan test) The results were as follows. 1. The amount of tensile load of the wrought wire clasp was significa-ntly different from the cast round or half round clasp(P<0.05) 2. The more amount of the undercut, the more tensile load was need-ed to dislodge the clasp. There were significant difference among them(P<0.05) 3. The molar showed higher tensile load than the premolar, and there was significant difference(P<0.05) 4. The means of tensile load according to clasp types showed signific-ant differences at the molar between wrought wire clasp and cast clasp (P<0.05), but did not at the premolar
Arm ; Bicuspid ; Crowns ; Molar ; Periodontium ; Pliability ; Tooth

Since the concept of osseointegration was introduced by Branemark of Sweden, dental implants have been used for various dental prosthetic treatments. The survival rate of dental implant is likely to be closely related to the total biomechanical role of each component of implant system. The use of interchangeable component is very attractive for dental practitioners because such an approach would save treatment cost, flexibility of prosthetic treatment options as well as conveniences. Therefore, the use of interchangeable implant system has been increasing without scientific assessment of safety and efficacy of various interchangeable implant system. The purpose of this study, therefore, were to compare the geometric characteristic of four interchangeable dental implant screws and the loosening torque of these screws. Four types of dental implant screws tested in this study were Nobelpharma, 3i, Impla-med, Restore. Four screws each of the test specimens were subjected for scanning electron microscopic examinations under the same condition and a 35x magnified standard SEM picture was objected from each test specimen using JSM-5200 scanning microscope. From each of the SEM pictures, eight parameters, i.e., diameter of screw head, screw length, thread pitch, major diameter, neck diameter, neck length, crest width and root width were determined using a caliper. The measurement for each parameters were then corrected for their magnification factor. The loosening torque were also determined by using a torque gauge. All of the measurements were statistically analyzed by ANOVA test and multiple range test. Statistical significance was set in advance at the probability level of less than 0.05. All analyses were done with SPSS software for the personal computer. The conclusion obtained from this studies were summarized as the following; 1. No statistically significances were noted in the thread pitch, and crest width in the four screws, and in the case of major diameter, the Impla-med screw was significantly smaller than the other three screws (p<0.05). Therefore, four implant bolts could be physically inserted in a abutment nuts. 2. The diameter of screw head was decreased in the order of Restore, 3i, Nobelpharma, Impla-med screws and the length of screws were decreased in the order of 3i, Restore, Nobelpharma and Impla-med. The diameter of neck was decreased in the order of Impla-med, Restore, Nobelpharma, 3i screws. The differences of each of these parameters were statistically significant (p<0.05). The width of root of screws were decreased in the order of Nobelpharma, Impla-med, Restore and 3i. The differences among Nobelpharma and Impla-med, Restore and 3i were statistically significant (p<0.05). 3. When the screws were loosening 1, 3, 4 and 5 times, the loosening torque for Impla-med and 3i screws were significantly higher than that of Nobelpharma or Restore screws (p<0.05). However, when statistically smaller than that of 3i, Restore or Nobelpharma screws (p<0.05).
Dental Implants ; Head ; Health Care Costs ; Microcomputers ; Neck ; Nuts ; Osseointegration ; Pliability ; Survival Rate ; Sweden ; Torque

A 51-year-old Korean woman presented with a non-tender, well-demarcated, reddish, edematous patch on the right anterior chest where a previous mastectomy and radiation therapy had been performed. She had been diagnosed as having infiltrating ductal carcinoma of the right breast about 1 year ago. Histopathological findings of the skin lesions were consistent with inflammatory metastatic carcinoma of the breast. Inflammatory carcinoma or carcinoma erysipeloides is a well-established entity most frequently associated with carcinoma of the breast. It is characterized by dermal lymphatic invasion by malignancy and clinically should be distinguished from erysipelas or cellulitis. We describe a case of inflammatory metastatic carcinoma derived from an infiltrating ductal carcinoma of the breast which can be clinically confused with radiation dermatitis.
Breast* ; Carcinoma, Ductal ; Cellulitis ; Dermatitis ; Erysipelas ; Erysipeloid ; Female ; Humans ; Mastectomy ; Middle Aged ; Skin ; Thorax

Angiosarcoma is a rare malignant vascular tumor of endothelial cell origin. Most lesions of cutaneous angiosarcoma occur over the face and scalp. We experienced a case of angiosarcoma of the scalp in a 63-year-old man. Multiple pea-sized erythematous papules and nodules developed on the forehead 6 months ago. Thereafter, the lesions have extended to make violaceous, compressible and hemorrhagic plaques. On histologic examination, there were irregular, often anastomosing vascular channels lined by the atypical endothelial cells in the dermis.
Dermis ; Endothelial Cells ; Forehead ; Hemangiosarcoma* ; Humans ; Middle Aged ; Scalp*