47 research outputs found
Declining incidence of esophageal cancer in the Turkmen Plain, eastern part of the Caspian Littoral of Iran: A retrospective cancer surveillance
Background: Previous studies have shown that upper gastrointestinal cancers are the most common cancers in Caspian Littoral, and rate of esophageal cancer (EC) in Iranian Turkmens residing in the Eastern part of littoral are among the highest in the world. Our aim was to reassess the rate 30 years later and following socioeconomic changes in the region. Methods: A comprehensive retrospective search was undertaken to find all new cancer cases during the 1996-2000 period. Diagnosis of cancer was based on histopathological reports in 68.2, clinical and/or radiological evidence in 29.7 and death certificate only (DCO) in 2.1 of the cases. Results: A total of 5143 new cancer cases were registered of whom 3063 (59.6) were males. The median (IQR) age was 60 (44-69) years. Age-standardized rates (ASR) for all cancers in males and females were 134.7 and 104.5 per 100,000, respectively. Based on ASR, the top five common cancers in males (excluding skin cancer) were cancers of esophagus (43.4), stomach (27.8), colorectal (10.7), bladder (7.8) and oral cavity (6.3), while in females cancer of esophagus (36.3) was followed by cancers of breast (15.7), stomach (8.3) colorectal (6.6) and cervix (3.6). Conclusion: We conclude that EC incidence rate has decreased to less than half the rate reported 30 years ago, while the incidence rates of colorectal and breast cancers have increased significantly. © 2006 International Society for Preventive Oncology. Published by Elsevier Ltd. All rights reserved
Prognostic factors for esophageal squamous cell Carcinoma-A Population-Based study in Golestan province, Iran, a high incidence area
Golestan Province in northern Iran is an area with a high incidence of esophageal squamous cell carcinoma (ESCC). We aimed to investigate prognostic factors for ESCC and survival of cases in Golestan, on which little data were available. We followed-up 426 ESCC cases participating in a population-based case-control study. Data were analyzed using the Kaplan-Meier method and the Cox proportional hazard models. Median survival was 7 months. Age at diagnosis was inversely associated with survival, but the association was disappeared with adjustment for treatment. Residing in urban areas (hazard ratio, HR = 0.70; 95 CI 0.54-0.90) and being of non-Turkmen ethnic groups (HR = 0.76; 95 CI 0.61-0.96) were associated with better prognosis. In contrast to other types of tobacco use, nass (a smokeless tobacco product) chewing was associated with a slightly poorer prognosis even in models adjusted for other factors including stage of disease and treatment (HR = 1.38; 95 CI 0.99-1.92). Opium use was associated with poorer prognosis in crude analyses but not in adjusted models. Almost all of potentially curative treatments were associated with longer survival. Prognosis of ESCC in Golestan is very poor. Easier access to treatment facilities may improve the prognosis of ESCC in Golestan. The observed association between nass chewing and poorer prognosis needs further investigations; this association may suggest a possible role for ingestion of nass constituents in prognosis of ESCC. © 2011 Aghcheli et al
Clinical Relevance of HER-2/neu Overexpression in Patients With Testicular Nonseminomatous Germ Cell Tumor
Introduction: Recent scientific attention has focused on the role of growth factors in the progression of cancer. HER-2/neu is an epidermal growth factor receptor that is demonstrated to have correlation with poor prognosis of many cancers. This study evaluated the overexpression of HER-2/neu protein and its clinical importance in nonseminomatous germ cell tumors of the testis. Materials and Methods: Testis specimens of 54 patients with testicular nonseminomatous germ cell tumors, referred to Omid Hospital from 2001 to 2007, were re-evaluated and the patients’ records were reviewed. Patients’ age, tumor subtype, tumor stage, tumor markers, therapeutic response, and disease-free survival were assessed and the specimens were evaluated for the degree of HER-2/neu expression using an immunohistochemistry method. Results: Immunohistochemical staining was performed for 54 specimens. Overexpression of HER-2/neu was seen in 33.3% of the patients with nonseminomatous germ cell tumors, especially in those with teratocarcinoma subtype compared to those with mixed germ cell tumors or embryonal cell carcinoma. However, HER-2/neu overexpression did not show any correlation with tumor stage, therapeutic response, disease-free survival, age, beta-human chorionic gonadotropin, or ?-fetoprotein. Conclusion: We observed overexpression of HER-2/neu receptor in teratocarcinoma subtype of germ cell tumor. We suggest further studies to evaluate the clinical importance of this finding
Etching a Fiber Post Surface with High-concentration Bleaching Agents
Introduction: Commonly, resin composites/cements fail to achieve proper bonding to fiber posts when their surfaces have not been previously etched. This study evaluated the effect of the concentration and application mode of hydrogen peroxide on the surface topography and bond strength of resin composite to glass-fiber posts. Methods and Materials: Fiber posts were immersed in 24% or 35% solutions (a high-concentration bleaching agent) of hydrogen peroxide (H2O2), or these solutions were applied over the post surface using a microbrush (n=10). Posts without any treatment were used as a control. After etching, the posts were silanated and an adhesive was applied. The posts were positioned in a mold, and a resin composite was incrementally inserted and light-cured. The post/resin assembly was serially sectioned into several beams that were subjected to a tensile bond strength test. The data were subjected to the two-way analysis of variance and Tukey test (α=0.05). The Dunnet's test was used to compare the experimental conditions to the control. The surface topography was analyzed using scanning electronic microscopy. Results: The non-etched post presented a relatively smooth surface without fiber exposure. Except for the application of 24% H2O2, the other experimental conditions increased the number of exposed fibers and bond strength in relation to the control. Although immersion resulted in higher values for the 24% H2O2 application, the mode of application did not alter bond strength when 35% H2O2 was used.
Conclusions: The effect of the mode of application of H2O2 depended on its level of concentration. A high-concentration bleaching agent improved the bond strength of the resin composite to the post surface, regardless of which mode was used
Estudo longitudinal do sucesso clÃnico-radiográfico de dentes tratados com medicação intracanal de hidróxido de cálcio
Effect of a 16% Carbamide Peroxide Bleaching Gel on Enamel Staining Susceptibility
Statement of Problem: Due to the growing popularity of vital bleaching by CarbamidePeroxide it is imperative to understand the effect of such agents on enamel and dentine.Purpose: The purpose of this study was to evaluate the effect of a 16% carbamide peroxide bleaching gel; Vivastyle on enamel staining susceptibility.Materials and Methods: Thirty bovine specimens were selected and randomly divided into two groups of fifteen. The experimental group was subjected to Vivastyle gel and then was immersed in coffee, for half an hour daily for three weeks. The control group was only immersed in coffee. The teeth were evaluated by colorimeter readings to measure L*, a*, b* of each tooth. Total color differences between two colors (ΔE) were calculated using the following formula: ΔE= [(ΔL*) 2 + (Δa*) 2+ (Δb*) 2].ΔE1 represent color difference after bleaching; ΔE2: bleached and immersed in coffee,and ΔE3 immersed in coffee.Results: Mean color difference were: 9.478, 13.808, and 7.230 for ΔE1, ΔE2, and ΔE3 respectively. Paired comparison by Duncan test showed that there was a significant difference between ΔE1 and ΔE2 (P0.000). t-test showed that there was no significant difference between ΔE3 and ΔE1. (P=0.08), however, ΔE3 had significant difference with ΔE2 (P0.000).Conclusion: After vital bleaching, the enamel staining susceptibility is significantly increased
A Histopathologic Study on Pulp Response to Glass Ionomer Cements in Human Teeth
Statement of Problem: Despite the wide range of new dental materials, there is still a need for biomaterials demonstrating high biocompatibility, antimicrobial effects and ideal mechanical properties.Purpose: The aim of this study was to histologically evaluate the pulpal response to a conventional glass ionomer, a resin modified glass ionomer and a calcium hydroxide in human teeth.Materials and Methods: Fifty five deep class V cavities were prepared in premolars of 31 patients and were divided into 3 groups based on application of the following liners:resin modified glass ionomer (Vivaglass Liner), conventional glass ionomer (ChembondSuperior) and calcium hydroxide (Dycal). After applying varnish, teeth were filled with amalgam. Each group was further divided into three subgroups according to time intervals of 7, 30 and 60 days. Teeth were then extracted and their crowns were fixed in formalin. Each sample was assessed microscopically for odontoblastic changes,inflammatory cell infiltration, reactionary dentin formation, remaining dentinal thickness and presence of microorganisms. Statistical analysis including Kruskal Wallis and Mann Whitney was carried out for comparison of mean ranks. (P=0.05).Results: In the Vivaglass Liner group, pulpal response was significantly higher on day 7 as compared to days 30 and 60 (P<0.05). Reactionary dentin production was significantly lower after 7 days than after 60 days for all materials (P<0.05). There wasno statistically significant difference in pulpal responses among the three groups during the same time intervals (P>0.05). There was no correlation between pulpal responses with micro-organisms and remaining dentin thickness (P>0.05).Conclusion: According to the results of this study, light-cured glass ionomer as well as the other tested lining materials were determined to be biologically compatible with vital pulps in deep cavities of sound human teeth
Microleakage Evaluation of Adhesive Systems Following Pulp Chamber Irrigation with Sodium Hypochlorite
Background and aims. This in vitro study evaluated the effect of delaying composite resin restorative procedures
bonded with total-etch and self-etch adhesive systems on microleakage following root canal irrigation with sodium hypochlorite
(NaOCl) solution.
Materials and methods. The roofs of pulp chambers and roots (1–2 mm below furcation) of 40 human first molar teeth
were cut and pulp tissues completely removed. The teeth were randomly divided into two main groups (n = 20). Group E
(experimental) was irrigated with 5% NaOCl and group C (control) was left untreated. For the experimental group, after
obturation of root canals with gutta-percha and sealing the cavity with Cavit, the specimens were stored in artificial saliva
for two weeks. Then each group was divided into two subgroups according to the total-etch or self-etch adhesive application
protocol: Scotchbond Multi-Purpose and Clearfil SE Bond. The specimens were restored with composite resin using each
bonding agent: Z250 and Clearfil Photo Core, respectively. Fluid filtration method was used for evaluation of microleakage.
Data was analyzed using two-way ANOVA (α = 0.05).
Results. Two types of dentin adhesive systems showed no statistically significant differences in microleakage (P = 0.77).
NaOCl-treated groups demonstrated significantly higher microleakage values compared to the non-NaOCl-treated groups (P
= 0.001). The interaction between the two factors was not significant (P = 0.78).
Conclusion. Differences in inlay temperature had no effect on microleakage. CAD/CAM inlays had lower cement thickness
than laboratory-made inlays, but this was not related to their microleakage
A Histopathological Study of Direct Pulp Capping with Adhesive Resins
Statement of Problem: Recently, it has been proposed that different adhesive materials can be used for direct pulp capping. Previous studies have demonstrated that multi steps dentin adhesives could form reparative dentin similar to calcium hydroxide (CH).Purpose: The aim of this study was to evaluate the histological pulp response of ninety mechanically exposed cat pulps to two adhesive resins (Scotch Bond MP and Single Bond 3M) were compared with a calcium hydroxide cement (Dycal, Dentsply).Materials and Methods : Class V facial cavities with similar pulpal exposures were prepared in canines. In the experimental groups phosphoric acid was used to etch the enamel and dentin and pulp exposure, and after it dentin adhesives was applied. The exposure point of the control group was capped with Dycal then the remainder of the cavities was etched and a dentin adhesive (single bond) was applied. All of the cavities were restored with a composite resin (Z 100) in usual manner. The animals were scarified after 7, 30 and 60 days (n=30), and the pulp evaluated histologically, statistical analysis was carried out with Kruskal- Wallis test (a=0.05).Results: The data showed that most of the cases had mild inflammation of pulp tissue.There was no significant difference in inflammatory reaction of pulp by Dycal and two adhesive systems, severe inflammatory reaction of pulp was observed only in most of the 30- day Single Bond group. Soft tissue organization of dentin bridge was less than ScotchBond and Dycal groups, the differentiation of dentin bridge was less than Scotch Bond group after 7 days.Conclusion: Slight inflammatory cell infiltration was the main reaction of exposed pulp when two commercially available adhesive resins were placed directly on the exposed pulp.There was no significant difference in inflammatory reaction of pulp between Dycal and two adhesive systems after 7 days and 60 days. After 7 days most of the specimens showed an amount of predentin deposition