STATEMENT OF PROBLEM: Resin cements are widely used in adhesive dentistry specially on all ceramic restorations. It is needed to find out adequate bonding strength between different porcelain surface treatments, commercially available porcelains, and different resin cement systems. PURPOSE: The purpose of this study was to evaluate shear bond strength of resin cements bonded to porcelains in three different modalities; 5 different porcelain surface treatments, 3 different resin cement systems and 3 different commercially available pressable porcelains. MATERIAL AND METHOD: This study consisted of 3 parts. Part I examined the effect of five different surface treatments on the pressable porcelain. Fifty discs (5 mm in diameter and 3 mm in height) of Authentic porcelain were randomly divided into 5 groups (n = 10). The specimens were sanded with 320 grit SiC paper followed by 600 grit SiC paper. The specimens were treated as follow: Group 1-Sandblasting (aluminum oxide) only, Group 2 - sandblasting/silane, Group - sandblasting/acid etching/silane, Group 4 - acid etching only, Group 5 - acid etching/silane. Part II examined the shear bond strength of 3 different resin cement systems (Duolink, Variolink II, Rely X ARC) on acid etching/ silane treated Authentic pressable porcelain. Part 3 examined the shear bond strength of Duolink resin cement on 3 different pressable porcelains (Authentic, Empress I, Finesse). All cemented specimens were stored in distilled water for 2 hours and tested with Ultradent shear bond strength test jig under Universal Instron machine until fracture. An analysis of variance(ANOVA) test was used to evaluate differences in shear bond strength. RESULT: The shear bond strength test resulted in the following: (1) Acid etched porcelains recorded greater shear bond strength values to the sandblasted porcelains. (2) Silane treated porcelains recorded greater shear bond strength values to non-silane treated porcelains. (3) There was no significant difference between sandblasting/acid etching/silane teated and acid etching/silane treated porcelains. However those values were much higher than other three groups. (4) The shear bond strength with Variolink II was lower than the value of Duolink or Rely X ARC. (5) The shear bond strength of Finesse was lower than the value of Authentic or Empress I.
Adhesives ; Ceramics ; Dental Porcelain* ; Dentistry ; Resin Cements* ; Silicon Dioxide ; Water

In the present study, we examined to determine the development of various lymphoid tissue including mucosa-associated lymphoid tissue (MALT), thymus, lymph node and liver. In order to investigate the relationship between the morphological events and the expression pattern of MIC2 antigen (CD99) during the development of lymphoid system, we performed the immunohistochemical study using DN16, a monoclonal antibody against MIC2 (CD99), on formalin-fixed and paraffin-embedded lymphoid sections in 68 human embryos and fetuses, between 5 and 39 gestational week (GW). Four neonates, an infant, and 5 adults are also included. CD99 has been expressed along the membrane of hepatocytes and sinusoidal endothelial cells for 10-28 GW, in when the liver the major site of hematopoiesis. In the thymus, CD99 was firstly detected in the presumptive epitheial cells at 10 GW. When the thymus matured and corticomedullary differentiation appeared, CD99 was exclusively expressed in cortical thymocytes. The CD99 expression in epithelial cells of MALT has initiated at 6 GW and 10 GW earlier than that at the onset of MALT development and its expression has been persisted during MALT formation especially 16-25 GW. The finnding that CD99 antigen was expressed in epithelial cells during the development of MALT rnight provide a means to identify a novel epithelial differentiated substance. In addition, endothelial cells that are present in various organs such as liver and small intestine concurrently expressed CD99 antigen and its expression persisted to late fetal period. This point rnight suggest that CD99 antigen regulate the irnigration of lymphocytes from liver, major hematopoietic organ, to thymus or peripheral lyrnphoid organ via the interaction between endothelial cells and lymphocytes.
Adult ; Embryonic Structures* ; Endothelial Cells ; Epithelial Cells ; Fetus* ; Hematopoiesis ; Hepatocytes ; Humans* ; Infant ; Infant, Newborn ; Intestine, Small ; Liver ; Lymph Nodes ; Lymphocytes ; Lymphoid Tissue* ; Membranes ; Thymocytes ; Thymus Gland

A large body of evidence indicates that Helicobacter pylori is involved in the pathogenesis of chronic gastritis and peptic ulcers. Several techniques are currently used for detecting H. pylori. Recently the immunohistochemical method was introduced for rapid detection of H. pylori. To compare the result of the immunohistochemical method with those obtained by microbiologic methods, we glean formalin fixed, paraffin embbeded gastric and duodenal biopsy specimens from 85 patients with upper gastrointestinal symptoms. We set fifty cases which H. pylori was cultivated and identified by Gram stain as Group I, and thirty-five cases without H. pylori in Gram stain and culture as Group II. The results were as follows. 1) The sensitivity and the specificity of immunohistochemical method were 94% and 80% compared with the microbiologic method. Positive and negative predictive value of the immunohistochemical method were respectively 87% and 90%. However, in seven cases of Group II, H. pylori were identified by immunohistichemical method. 2) Immunohistochemical staining exhibited bacteria that were present in the mucus layer, the surface of the gastric mucosa and metaplastic gastric epithelium in duodenum. With reference to the distribution and density of H. pylori in Group I and II, a significant correlation existed between microbiologic results and bacterial load of the biopsy specimen (p<0.01). 3) Chronic inflammation of gastric biopsies were seen in all 45 H. pylori-positive cases(100%) and 16 out of 19 H. pylori-negative cases(84%). The degree of chronic inflammation was more severe in positive cases than negative cases. Activity of inflammation was seen 98% of H. pylori-positive cases and 16% of H. pylori-negative cases. Intestinal metaplasia was seen 40% of H. pylori-positive cases and 58% of H. pylori-negative cases. Lymphoid follicles and aggregates were seen in 47%(27 cases) of H. pylori-positive cases. Among 47%, cases with lymphoid follicles were 9%(4 cases) and cases with lymphoid aggregates were 38%(17 cases). In H. pylori-negative cases, lymphoid follicles and aggregates were seen in 16%(3 cases). It is possible to obtain samples from most of the individuals who underwent the endoscopy in Korea. And this method is simple, rapid and sensitive. We conclude that the immunohistochemical method is another useful diagnostic tool for detection of Helicobacter pylori.
Predictive Value of Tests ; Biopsy

No abstract available.
Apgar Score* ; Humans ; Smoke* ; Smoking*

No abstract available.
Fallopian Tubes* ; Female ; Infertility* ; Spermatozoa*

No abstract available.
Aged* ; Female ; Humans ; Sarcoma, Kaposi*

No abstract available.
Aged* ; Female ; Humans ; Sarcoma, Kaposi*

No abstract available.
Child* ; Humans ; Urinary Tract Infections* ; Urinary Tract*

No abstract available.
Child* ; Humans ; Urinary Tract Infections* ; Urinary Tract*