No abstract available.
Infertility* ; Laparoscopy*

No abstract available.

No abstract available.
Arthritis*

STATEMENT OF PROBLEM: Recently Yttrium-stabilized tetragonal zirconia polycrystal (Y-TZP) has been introduced due to superior flexural strength and fracture toughness compared to other dental ceramic systems. Although zirconia has outstanding mechanical properties, the phenomenon of decrease in the life-time of zirconia resulted from degradation in flexural strength after low temperature aging has been reported. PURPOSE: The objective of this study was to investigate degradation of flexural strength of Y-TZP ceramics after various low temperature aging treatments and to evaluate the phase stability and micro-structural change after aging by using X-ray diffraction analysis and a scanning electron microscope (SEM). MATERIAL AND METHODS: Y-TZP blocks of Vita In-Ceram YZ (Vita Zahnfabrik, Bad Sackingen, Germany) were prepared in 40 mm (length) x 4 mm (width) x 3 mm (height) samples. Specimens were artificially aged in distilled water by heat-treatment at a temperature of 75, 100, 125, 150, 175, 200, and 225degrees C for 10 hours, in order to induce the phase transformation at the surface. To measure the mechanical property, the specimens were subjected to a four-point bending test using a universal testing machine (Instron model 3365; Instron, Canton, Mass, USA). In addition, X-ray diffraction analysis (DMAX 2500; Rigaku, Tokyo, Japan) and SEM (Hitachi s4700; Jeol Ltd, Tokyo, Japan) were performed to estimate the phase transformation. The statistical analysis was done using SAS 9.1.3 (SAS institute, USA). The flexural strength data of the experimental groups were analyzed by one-way analysis of variance and to detect statistically significant differences (alpha= .05). RESULTS: The mean flexural strength of sintered Vita In-Ceram YZ without autoclaving was 798 MPa. When applied aging temperature at below 125degrees C for 10 hours, the flexural strength of Vita In-Ceram YZ increased up to 1,161 MPa. However, at above 150degrees C, the flexural strength started to decrease. Although low temperature aging caused the tetragonal-to-monoclinic phase transformation related to temperature, the minimum flexural strength was above 700 MPa. CONCLUSION: The monoclinic phase started to appear after aging treatment above 100degrees C. With the higher aging temperature, the fraction of monoclinic phase increased. The ratio of monoclinic/tetragonal + monoclinic phase reached a plateau value, circa 75% above 175degrees C. The point of monoclinic concentration at which the flexural strength begins to decrease was between 12% and 54%.
Aged ; Aging ; Aluminum Oxide ; Ceramics ; Collodion ; Dental Porcelain ; Electrons ; Humans ; Phenothiazines ; Tokyo ; Water ; X-Ray Diffraction ; Yttrium ; Zirconium

PURPOSE: The purpose of this study was to investigate the diametral tensile strength of polymer-based temporary crown and fixed partial denture (FPD) materials, and the change of the diametral tensile strength with time. MATERIAL AND METHODS: One monomethacrylate-based temporary crown and FPD material (Trim) and three dimethacrylate-based ones (Protemp 3 Garant, Temphase, Luxtemp) were investigated. 20 specimens (the empty set 4 mm x 6 mm) were fabricated and randomly divided into two groups (Group I: Immediately, Group II: 1 hour) according to the measurement time after completion of mixing. Universal Testing Machine was used to load the specimens at a cross-head speed of 0.5 mm/min. The data were analyzed using one-way ANOVA, the multiple comparison Scheffe test and independent sample t test (alpha = 0.05). RESULTS: Trim showed severe permanent deformation without an obvious fracture during loading at both times. There were statistically significant differences among the dimethacrylate-based materials. The dimethacrylate-based materials presented an increase in strength from 5 minutes to 1 hour and were as follows: Protemp 3 Garant (23.16 - 37.6 MPa), Temphase (22.27 - 28.08 MPa), Luxatemp (14.46 - 20.59 MPa). Protemp 3 Garant showed the highest value. CONCLUSION: The dimethacrylate-based temporary materials tested were stronger in diametral tensile strength than the monomethacrylate-based one. The diametral tensile strength of the materials investigated increased with time.
Acrylic Resins ; Bisphenol A-Glycidyl Methacrylate ; Collodion ; Composite Resins ; Crowns ; Denture, Partial, Fixed ; Methacrylates ; Polymethacrylic Acids ; Tensile Strength

STATEMENT OF PROBLEM: Recently, resin cements have become more widely used and have been accepted as prominent luting cements. Current resin cements exhibit less microleakage than conventional luting cements. However, the constant contact with water and exposure to occlusal forces increase microleakage even in resin cements inevitably. Most bonding resins have been modified to contain a hydrophilic resin such as 2-hydroxyethylmethacrylate (HEMA) to overcome some of the problems associated with the hydrophobic nature of bonding resins. By virtue of these modifications, bonding resins absorb a significant amount of water, and there may also be significant stresses at bonding interfaces, which may adversely affect the longevity of restorations. Therefore the reinforcement of water stability of resin cement is indispensable in future study. PURPOSE: This study was conducted to examine the influence of water retention on microleakage of two resin cements over the period of 6 months. MATERIALS AND METHODS: 32 ex acted human teeth were used to test the microleakage of a single full veneer crown. Two resin cements with different components and adhesive properties - Panavia F (Kuraray Co., Osaka, Japan) and Super-Bond C&B (Sun Medical Co., Kyoto, Japan)- were investigated. The storage medium was the physiological saline solution changed every week for 1 month, 3 months, and 6 months. One group was tested after storage for 1 day. At the end of the each storage period, all specimens were exposed to thermocycling from 5.C to 55.C of 500 cycles and chewing simulation of 50,000 cycles, and then stained with 50% silver nitrate solution. The linear penetration of microleakage was measured using a stereoscopic microscope at x 40 magnification and a digital traveling micrometer with an accuracy of +/-3 um. Values were analyzed using two-way ANOVA test, Duncan's multiple range tests (DMRT). RESULTS: Statistically significant difference of microleakage was shown in the 3-month group compared with the 1-day or 1-month group in bot systems (p<0.05) and there were statistically significant differences in microleakage between the 3-month group and the 6-month group in both systems (p<0.05). The two systems showed different tendency in the course of increased microleakage during 3 months. In Panavia F, microleakage increased slowly throughout the periods. In Super-Bond C&B, there was no significant increase of microleakage for 1 month, but there was statistically significant increase of microleakage for the next 2 months. For the mean microleakage for each period, in the 3-month group, microleakage of Super-Bond C&B was significantly greater than that of Panavia F. On the other hand, in the 6-month group, microleakage of Panavia F was significantly greater than that of Super-Bond C&B (p<0.05). CONCLUSION: Within the limitation of this study, water retention of two different bonding systems influence microleakage of resin cements. Further studies with the longer observation periods in viro are required in order to investigate water stabilty and the bonding durability of the resin cement.
Adhesives ; Bite Force ; Crowns ; Hand ; Humans ; Longevity ; Mastication ; Resin Cements* ; Silver Nitrate ; Sodium Chloride ; Tooth ; Virtues ; Water*

For the purpose of ascertaining the status of physical growth and health status of the University students, an intensive survey was conducted by the authors towards a total of 1,250 (Male 792, Female 458) who passed the written entrance examination at the Kyung Hee University in 1972. The items included the measurements on physical growth, various physical and nutritional indices, status of visual distourbance, dental status and tuberculosis. The findings and results can be summarized as follows ; 1. Physical Growth and Development. i) The average of body height by anthropometric was 169.39+/-5.05cm in male and 157.45+/-4.43cm in female. ii) The averages of body weight by sex were 59.42+/-6.47Kg and 51.81+/-5.21Kg, respectively. iii) The averages of chest-girth were 87.18+/-5.30cm and 80.51+/-4.53cm. iv) The averages of sitting-height were 92.21+/-2.79cm and 86.28+/-2.57cm. In all cases the male measurements were higher than female. 2. Various ludices about Physical Growth and Development; i) Relative body weight by sex were 35.08and 32.91, relative chestgirth 51.47 and 51.13, and relative sitting-height 54.43, 54.79, respectively. ii) Rohrer index was 1.222 in males and 1.327 in females, Kaup index 2.071 and 2.089, Verveck index 86.54 and 84.04, and Pelidisi index 91.15 and 93.08, respectively. 3. Status of visual distourbance. The vision of the students under 0.8 with Landolt's testing chart was 45.4% in left eye and 46.6% in right eye (male : 44.4% and 45.7%, female : 47.2% and 48.0%), while under 0.6in both visions was 41.0% and 40.5% (male 40.8% and 40.7%, female : 41.5% and 40.2%),respectively. 4. Dental Status. Out of total 19.4% (male 19.2%, female 19.6%) had gingivitis, the female incidence rate of gingivitis was higher than male. Average number of teeth in each subjects was 29.6 teeth; male had 29.9 teeth and female had 29.1 teeth. The caries rate was 78.9%(male 75.6%, female 84.5%), the female caries rate was higher than male. The average number of i) Caries per tooth rate was 8.5% in male and 9.2% in female, ii) Missing per tooth rate was 0.3% and 0.2%, iii) Filling per tooth rate was 3.9% and 4.2%, in all cases, the female incidences were higher than the male. The average number of D.M.F. was 3.8 teeth in male and 4.0 teeth in female, female was higher than male. The average rate of D.M.F. was 12.7% in male and 13.7 in female, female was higher than male. 5. Pulmonary infiltration. Among the total, 53 students were diagnosed as pulmonary infiltration (tuberculosis), of whom 51 were minimal cases, one were moderately advanced case and one were far advanced case.
Body Height ; Body Weight ; Female ; Gingivitis ; Growth and Development ; Humans ; Incidence ; Male ; Nutrition Assessment ; Tooth ; Tuberculosis

For the purpose of ascertaining the status of physical growth and health status of the University students, an intensive survey was conducted by the authors towards a total of 1,250 (Male 792, Female 458) who passed the written entrance examination at the Kyung Hee University in 1972. The items included the measurements on physical growth, various physical and nutritional indices, status of visual distourbance, dental status and tuberculosis. The findings and results can be summarized as follows ; 1. Physical Growth and Development. i) The average of body height by anthropometric was 169.39+/-5.05cm in male and 157.45+/-4.43cm in female. ii) The averages of body weight by sex were 59.42+/-6.47Kg and 51.81+/-5.21Kg, respectively. iii) The averages of chest-girth were 87.18+/-5.30cm and 80.51+/-4.53cm. iv) The averages of sitting-height were 92.21+/-2.79cm and 86.28+/-2.57cm. In all cases the male measurements were higher than female. 2. Various ludices about Physical Growth and Development; i) Relative body weight by sex were 35.08and 32.91, relative chestgirth 51.47 and 51.13, and relative sitting-height 54.43, 54.79, respectively. ii) Rohrer index was 1.222 in males and 1.327 in females, Kaup index 2.071 and 2.089, Verveck index 86.54 and 84.04, and Pelidisi index 91.15 and 93.08, respectively. 3. Status of visual distourbance. The vision of the students under 0.8 with Landolt's testing chart was 45.4% in left eye and 46.6% in right eye (male : 44.4% and 45.7%, female : 47.2% and 48.0%), while under 0.6in both visions was 41.0% and 40.5% (male 40.8% and 40.7%, female : 41.5% and 40.2%),respectively. 4. Dental Status. Out of total 19.4% (male 19.2%, female 19.6%) had gingivitis, the female incidence rate of gingivitis was higher than male. Average number of teeth in each subjects was 29.6 teeth; male had 29.9 teeth and female had 29.1 teeth. The caries rate was 78.9%(male 75.6%, female 84.5%), the female caries rate was higher than male. The average number of i) Caries per tooth rate was 8.5% in male and 9.2% in female, ii) Missing per tooth rate was 0.3% and 0.2%, iii) Filling per tooth rate was 3.9% and 4.2%, in all cases, the female incidences were higher than the male. The average number of D.M.F. was 3.8 teeth in male and 4.0 teeth in female, female was higher than male. The average rate of D.M.F. was 12.7% in male and 13.7 in female, female was higher than male. 5. Pulmonary infiltration. Among the total, 53 students were diagnosed as pulmonary infiltration (tuberculosis), of whom 51 were minimal cases, one were moderately advanced case and one were far advanced case.
Body Height ; Body Weight ; Female ; Gingivitis ; Growth and Development ; Humans ; Incidence ; Male ; Nutrition Assessment ; Tooth ; Tuberculosis

No abstract available.
Leg*

STATEMENT OF PROBLEM: Zirconia-based restorations have the common technical complication of delamination, or porcelain chipping, from the zirconia core. Thus the shear bond strength between the zirconia core and the veneering porcelain requires investigation in order to facilitate the material's clinical use. PURPOSE: The purpose of this study was to evaluate the bonding strength of the porcelain veneer to the zirconia core and to other various metal alloys (high noble metal alloy and base metal alloy). MATERIAL AND METHODS: 15 rectangular (4x4x9mm) specimens each of zirconia (Cercon), base metal alloy (Tillite), high noble metal alloy (Degudent H) were fabricated for the shear bond strength test. The veneering porcelain recommended by the manufacturer for each type of material was fired to the core in thickness of 3mm. After firing, the specimens were embedded in the PTFE mold, placed on a mounting jig, and subjected to shear force in a universal testing machine. Load was applied at a crosshead speed of 0.5mm/min until fracture. The average shear strength (MPa) was analyzed with the one-way ANOVA and the Tukey's test (alpha= .05). The fractured specimens were examined using SEM and EDX to determine the failure pattern. RESULTS: The mean shear strength (+/- SD) in MPa was 25.43 (+/- 3.12) in the zirconia group, 35.87 (+/- 4.23) in the base metal group, 38.00 (+/- 5.23) in the high noble metal group. The ANOVA showed a significant difference among groups, and the Tukey's test presented a significant difference between the zirconia group and the metal group. Microscopic examination showed that the failure primarily occurred near the interface with the residual veneering porcelain remaining on the core. CONCLUSION: There was a significant difference between the metal ceramic and zirconia ceramic group in shear bond strength. There was no significant difference between the base metal alloy and the high noble metal alloy.
Ceramics ; Collodion ; Dental Porcelain ; Fires ; Fungi ; Polytetrafluoroethylene ; Shear Strength ; Zirconium