The aim of this study is to survey the pre INSTRUMENTATION signs and symptoms or after INSTRUMENTATION pain in teeth with occlusal surface reduction. This experimental study (match clinical trial) was done on 120 patients who needed endodontic therapy on their molars. Excluded criteri as follows the patients who used antibiotics or analgesics, those who had bruxism or clenching. Patients with less than three pairs of antagonistic posterior teeth on each arch. Those who had teeth with greater than Cl I mobility or pocket depths > 5 mm, the teeth with prosthetic crowns, and the patients with over INSTRUMENTATION or perforation during treatment.The patients were divided into two groups. The first group were the teeth with vital pulps, having pre treatment pain, sensitive to percussion and without preradicular radiolucency. The second group was the teeth with necrotic pulps. without pre treatment pain, not sensitive to percussion and with preradicular radiolucency. Each group was divided into case and control subgroups. Following canal preparation occlusal surface reduction was done; the case of subgroups of the both groups, and the patients were given questionnaires to register their pain rate during collected in the next session and the data were analyzed by X2 test (P<=0.05)In the first group, there was an statistical correlation between pre treatment and after INSTRUMENTATION pain following occlusal reduction, while in the second group there was no meaningful relation between them.It was suggested that, in order to reduce after INSTRUMENTATION pain the occlusal reduction be done in patients with vital pulps, having pretreatment pain and sensitivity to precussion without preradicular radiolucency.

Statement of Problem: Root canal cleaning and elimination of the source of infection are the most important basis and the main requirements for successful root treatment since the main cause of failure in root treatment is the permeation of bacteria or their products into the periapical tissues. Nowadays, the newly designed and prcsented instruments for canal INSTRUMENTATION can improve root treatment. Purpose: The aim of this study was to compare the decrease in the number of intracanal Enterococcus-faecalis (Ef) among three mechanical INSTRUMENTATION methods: manual (K-type) and rotary (Race, Profile). Materials and Methods: In this experimental study, 30 single rooted teeth were selected. Three cases were considered as negative and three cases as posetive controls and 24 remainder cases were divided into three experimental groups. All root canals were inoculated by Ef and samples were taken from all canals to prepare microbial cultures. The three INSTRUMENTATION procedures were: - Crown- down technique with K-type manual system file - Crown- down technique with Profile rotary system - Crown- down technique wiht Race rotary system After INSTRUMENTATION, microbial cultures were taken from root canals and the reduction rate of bacteria were evaluated and compared using one way ANOVA test with P<0.05 as the limit of significance. Results: There was no significant difference among the three INSTRUMENTATION procedures regarding bacterial elimination. Conclusion: According to the finding of this study, K-type manual file, Profile and Race rotary systems, all can be used in canal instrumentaion. However, since manual files are more accessible and require less equipment compared with rotary systems, and since the ability of all of these methods is identical regarding bacterial elimination, manual files can be used in straight canal instead of rotary systems.  

Molecular imaging is a rapidly emerging field, providing noninvasive visual quantitative representations of fundamental biological processes in intact living subjects. The novelty of multimodality molecular imaging lies in the fact that it seeks to shed new light on both structure and function by creating images that directly or indirectly reflect specific cellular and molecular events (e.g. gene expression) that can reveal pathways and mechanisms responsible for disease within the context of physiologically authentic and intact environments within living subjects. Since the commercial introduction of PET/CT in 2001 and SPECT/CT in 2004, adoption of the technology has been rapid, particularly for oncology. Advances in CT and PET INSTRUMENTATION have been incorporated into the very latest PET/CT designs, and SPECT/CT has also benefited from the advances in CT technology. The latest addition to multimodality clinical imaging is a combined MR/PET device. The availability of fast scintillators with high stopping power has revived interest in PET time-of-flight in order to increase signal to noise ratio in PET imaging. There has been significant progress during the past few years in image reconstruction methods through the introduction of statistically based algorithms and resolution recovery into the clinical setting. The idea of using energy resolve CT for attenuation correction of PET data is an active research arena in multimodality imaging. Within the past couple years, the most widely-addressed issue related to CT-based attenuation correction has been respiratory motion and the artifacts created by the mismatch between CT and PET. An application for which PET/CT is also having an impact is that of radiotherapy treatment planning. Molecular imaging is increasingly being used to monitor response to therapy, both for chemotherapy and for radiation therapy, and for combinations of each. This review talk will follow the development of multimodality molecular imaging INSTRUMENTATION for clinical use from conception to present-day technology and assess the status and future potential for such devices.

Websites are currently considered as optimal instruments for linking organizations, users, and citizens. Parallel with the increasing access to Internet, the number of website users has expended and their quality has been an issue of concern to many researchers. Websites are originally designed to meet the expectations of their users through providing the right information. The literature indicates that due to the wide range of websites, it is rather difficult to provide a generally-agreed definition for quality of websites. In this paper, after presenting a sketchy account of the website users’ conceptualization of the quality of websites, we will discuss the underlying factors of success of websites. The paper closes with an explanation of the standards for designing websites.

In this paper, using the data obtained from the measurement of convergence of Gavoshan Tunnel and its access galleries, the ratio of horizontal to vertical in-situ stresses have been estimated from back calculations. This tunnel with a length of about 20.2km is located in the west of Iran, and in the vicinity of the main road of Sanandaj to Kermanshah. This tunnel has been excavated from inlet and outlet and from eight faces created by four access tunnels including Haltooshan, Tavankesh, Sabenav and Kachaleh galleries. Several instruments have been used for monitoring the behavior of the tunnel including tape extensometers, rod extensometers, total pressure cells, piezometers and load cells. The convergence of the tunnel has been measured using tape extensometers in several stations in the main tunnel and the access galleries. For the numerical modeling, the computer software Plaxis with computational modeling of jointed rock (JR) and triangular elements of 6 nodes in plane strain has been used. Considering that Gavoshan Tunnel is located in the zone of Sannadaj-Sirjan fault, assessment of the ratio of horizontal to vertical stress is important. Therefore a back analysis to calculate K value has been carried out. The results obtained from convergence measurements are analyzed for the different stations and are combined with the numerical analyses to evaluate the coefficient of lateral pressures. It is concluded that in the outlet region of the tunnel, Sarbenav, Haltooshan and Tavankesh access galleries, the ratio of horizontal to vertical in-situ stress exceeds one and in the inlet region of the tunnel, this ratio is less than one.

Background & Aims: Idiopathic scoliosis is the most common type of lateral curvature of the spine. 2-3% of children under 16 years old have idiopathic scoliosis greater than 10 degrees, but less than 10% of them require treatment. One treatment method is surgical correction and fusion and different types of INSTRUMENTATION have been used. The purpose of this study was to evaluate the results of segmental fixation of the spine with Cotrel - Dubousset (CD) INSTRUMENTATION that we have used in adolescent idiopathic scoliosis patients since 1999.Materials & Methods: Thirty patients (22 girls and 8 boys) with the average age of 10-18 years, had gone under one or two stages of the operation from 1999 to 2004. The amount of curves in sagital and coronal plans were measured on standing radiographs with cobb method. Control radiographs were taken immediately after the operation, then 3 month ,6 month later, and then yearly until 4 years.Results: The patients were followed up for 21 months. Average correction was 44.8% in coronal and 10.6 degrees in sagital plans. Apical vertebral rotation didn't correct significantly, and average rate of it was 0.46 degree. The average correction of apical vertebral translation was 3 cm (1.5-4 cm). Standing and sitting height was increased to 5 cm averagely.Conclusion: CD INSTRUMENTATION is a suitable method for correction of spinal deformities in both coronal and sagital plans, specially to preserve thoracic kyphosis and lumbar lordosis, and there is no requirement for post operative external immobilization.