No abstract available.

BACKGROUND: Nitric oxide (NO) is known to play causative role in the development of neuropathic pain following peripheral nerve injury. However, it is yet to be investigated whether the role of NO differs in pain modalities, such as mechanical and thermal stimuli. Also, it has not been investigated whether NO has different roles in the stages of neuropathic pain - its development and maintenance. METHODS: Neuropathic pain was induced by a resection of the lumbar dorsal root 5, 6 (L 5, 6). After N-nitro-L-arginine methyl ester (L-NAME), an NO synthase inhibitor was injected intrathecally or locally around the dorsal root, we observed the behavioral response to the mechanical and thermal stimuli. RESULTS: Mechanical and thermal allodynia was inhibited by the application of L-NAME before the dorsal root injury. However, L-NAME did not affect the mechanical and thermal allodynia during the maintenance of neuropathic pain. CONCLUSIONS: We suggest that NO in the spinal cord or injured perineural site may play an important role in the induction of neuropathic pain, and may be associated with mechanical and thermal allodynia.
Animals ; Hyperalgesia* ; Neuralgia* ; NG-Nitroarginine Methyl Ester ; Nitric Oxide Synthase ; Nitric Oxide* ; Peripheral Nerve Injuries ; Rats* ; Spinal Cord ; Spinal Nerve Roots

STATEMENT OF PROBLEM: Macroscopic and especially microscopic properties of implant surfaces play a major role in the osseous healing of dental implants. Dental implants with modified surfaces have shown stronger osseointegration than implants which are only turned (machined). Advanced surface modification techniques such as anodic oxidation and Ca-P application have been developed to achieve faster and stronger bonding between the host bone and the implant. PURPOSE: The purpose of this study was to investigate the effect of surface treatment of titanium dental implant on implant stability after insertion using the rabbit tibia model. MATERIAL AND METHODS: Three test groups were prepared: sandblasted, large-grit and acid-etched (SLA) implants, anodic oxidized implants, and anodized implants with Ca-P immersion. The turned implants served as control. Twenty rabbits received 80 implants in the tibia. Resonance frequencies were measured at the time of implant insertion, 2 weeks and 4 weeks of healing. Removal torque values (RTV) were measured 2 and 4 weeks after insertion. RESULTS: The implant stability quotient (ISQ) values of implants for resonance frequency analysis (RFA) increased significantly (P < .05) during 2 weeks of healing period although there were no significant differences among the test and control groups (P > .05). The test and control implants also showed significantly higher ISQ values during 4 weeks of healing period (P < .05). No significant differences, however, were found among all the groups. All the groups showed no significant differences in ISQ values between 2 and 4 weeks after implant insertion (P > .05). The SLA, anodized and Ca-P immersed implants showed higher RTVs at 2 and 4 weeks of healing than the machined one (P < .05). However, there was no significant difference among the experimental groups. CONCLUSION: The surface-modified implants appear to provide superior implant stability to the turned one. Under the limitation of this study, however, we suggest that neither anodic oxidation nor Ca-P immersion techniques have any advantage over the conventional SLA technique with respect to implant stability.
Dental Implants ; Imidazoles ; Immersion ; Nitro Compounds ; Osseointegration ; Rabbits ; Tibia ; Titanium ; Torque

No abstract available.
Aneurysm, False* ; Embolization, Therapeutic* ; Hepatic Artery*

This study was undertaken to evaluate the status of human paragonimiasis in Kang Hwa Gun, Kyunggi Do, Korea from March 1973 to October 1975 by the use of intradermal screening test with Veronal buffered saline antigen. A total number of 7,352 (male 3,936; female 3,4l6) consisting of 3,447 primary school children, 2,689 middle school students, l,008 high school students of 9 Myuns out of 13 Myuns of this County and 208 residents of all age group in Kilgeong-Ri, Yangdo Myun were examined by the intradermal test with Paragonimus antigen. In order to detect Paragonimus egg, the sputum and the stool examinations were undertaken on the residents in Kilgeong-Ri. The infestation rate of crayfish with Paragonimus metacercaria was also examined in Konneung and Jeongha village in Kilgeong-Ri. The following results were obtained in this survey: As a whole, 16.6 per cent of the examiners showed positive reaction with sexual difference of 16.1% in male and 14.8 per cent in female. In age groups, the highest positive rate showed in middle school age group (17.1 per cent) than primary school (14.0 per cent) and high school age group (11.4 per cent). In regional differences of positive rates, the highest rate (28.4 per cent) showed at Yangdo Myun followed by Kilsang Myun (27.0 per cent), Hwado Myun (25.0 per cent), and Naega Myun(20.8 per cent). In the result of 208 residents Kilgeong-Ri, the positive of 36.1 per cent in male and 20.2 per cent in female. The highest positive rate showed in 10 to 19 age group (41.5 per cent). Among the residents in Kilgeong-Ri, Paragonimus eggs were detected in 11 residents by the sputum and the stool examinations. The infestation rate of crayfsh with Paragonimus metacercariae was 100 per cent (41 out of 41 crayfishes) in Konneung village, and 84.6 per cent (9 out of 13 crayfishes) in Jeongha village, Kilgeong-Ri The fluctuation of the infection rate of crayfish with Paragonimus metacercariae was decreased in Konneung village in 2 years after the treatment with Bilevon against 10 paragonimiasis patients.
parasitology-helminth-trematoda ; epidemiology-paragonimiasis ; Paragonimus westermani ; crayfish-Cambaroides similis

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

No abstract available.
Burns* ; Humans

If orthodontists and restorative dentists establish the interdisciplinary approach to esthetic dentistry, the esthetic and functional outcome of their combined efforts will be greatly enhanced. This article describes satisfying esthetic results obtained by the distribution of space for restoration by orthodontic treatment and porcelain laminate veneers in uneven space between maxillary anterior teeth. It is proposed that the use of orthodontic treatment for re-distribution of the space and the use of porcelain laminate veneers to alter crown anatomy provide maximum esthetic and functional correction for patients with irregular interdental spacing.
Crowns ; Dental Porcelain ; Dentistry ; Dentists ; Humans ; Tooth

If orthodontists and restorative dentists establish the interdisciplinary approach to esthetic dentistry, the esthetic and functional outcome of their combined efforts will be greatly enhanced. This article describes satisfying esthetic results obtained by the distribution of space for restoration by orthodontic treatment and porcelain laminate veneers in uneven space between maxillary anterior teeth. It is proposed that the use of orthodontic treatment for re-distribution of the space and the use of porcelain laminate veneers to alter crown anatomy provide maximum esthetic and functional correction for patients with irregular interdental spacing.
Crowns ; Dental Porcelain ; Dentistry ; Dentists ; Humans ; Tooth

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