Color matching and accurate shade selection are the challenging problems common to restorative dentistry. In ceramometal restorations, the type of substructure alloy affects the final color of bonded porcelain. Nickel- chromium alloy is the most commonly used one that its Iranian product, namely Minalux, is similar to Verabond2.Purpose: The aim of this study was to assess and compare various color dimensions resulting from Minalux and Verabond2 alloys. Materials and Methods: Nine disks, approximately 16 mm in diameter and 0.5 mm thickness, were cast from each alloy. Then, porcelain Vita VMK68 A2 was baked onto the entire test disks, following the manufacturer"s instruction. Color samples, at the same time and under the same conditions, was measured by Data color spectrophotometer in CIE Lab System and Munsel system under four light sources (A, C, D65 and TL81). Then MATLAB TOOL BOX Statistic 5.2 was used to determine mean and bilateral variance analysis.Results: It was indicated that the F value on hue, value and chroma was less than of the table value stated with 99% coefficient confidence, confirming Ho theory. In other words, there were not any significant differences between ceramometal disks made of Minalux and Verabond2 in the three dimensions of color.Conclusion: Having desirable physical, mechanical and biological properties, Verabond2 can be replaced by Minalux alloy.

In the response phase the most important step is to assess disaster after occurrence. By disaster assessment, we can obtain all the needed information for controlling, decision-making and also disaster planning. Lack of disaster assessment causes you to make unsuitable decisions based on limited or inadequate data which leads to imperfect disaster response. According to IFRC, disaster response operation will have an unsuitable function without disaster assessment. This paper presents the principles and concepts of disaster assessment.

Background and Aim: Several methods have been suggested to measure gingival thickness. This study aimed to assess the reliability of Visual assessment of facial gingival biotype of maxillary and mandibular teeth with or without using a periodontal probe in comparison with direct measurement. Materials and Methods: Sixty-seven healthy patients (25 women and 42 men) with a total of 100 hopeless teeth were selected for this study. Three methods were used to evaluate gingival thickness namely Visual assessment, Visual assessment with the use of periodontal probe and direct measurement using a caliper after extracting the hopeless tooth. One trained examiner performed all examinations. Patient demographics, tooth position, and the results of three assessments were recorded. The mean and standard deviation of gingival thickness were calculated. The three methods were compared using the chi-square test. Results: The accuracy of Visual assessment method for the “ thin biotype” was 96. 7% [positive predictive value (PPV)=96. 7%], while it was 10. 3% for “ thick biotype” [negative predictive value (NPV)=10. 3%]. The accuracy of Visual assessment with the use of periodontal probe for the thin biotype was 100% (PPV=100%), while it was 17. 1% for the thick biotype (NPV=17. 1%). The results of Visual assessment method alone and with the use of periodontal probe were incorrect in 37% and 29% of the cases, respectively and this difference was significant (P<0. 01). Conclusion: Gingival biotype identification by assessment with the use of periodontal probe is an adequately reliable method while Visual assessment of gingival biotype by itself is not sufficient for proper diagnosis.

Background and Aim: Objective measurement of Visual acuity using VEP is high valued in patients with low levels of cooperation. Therefore, this study aimed to investigate the effect of spatial frequency on VEP components in Visual acuity using Sweep VEP. Material and Methods: In this cross-sectional study 63 medical students with an age of 22. 81 ±,3. 93 were selected. After a completed eye examination, refractive error was determined, and best-corrected Visual acuity as subjective was recorded by the Freiburg Acuity contrast test. Sweep VEP using the Roland electrophysiology system was recorded for various spatial frequencies from 2 to 37. 5 cycles per degree. VEP components were the latencies of N1, P1, N135, and the amplitude of VEP. Results: Repeated measures of the ANOVA test showed that the effect of spatial frequency on latencies and amplitude of VEP was significant (P<0. 001). Paired T-test showed that there was a significant difference between subjective Visual acuity and extrapolation of Visual acuity with VEP (P<0. 001). Conclusion: According to the significant relationship between VEP amplitude and spatial frequencies of the Visual stimuli obtained in this study, the Sweep VEP technique can be used as a valid and objective tool in the determination of Visual acuity, especially in patients with low levels of cooperation.

The Visual impact is most obvious impact of development projects (urban development, roads, piping, gas, oil, water, electricity and Telephone, Web mining and industry) that they will have on the face of nature while usually in such projects has been less attention to it Therefore, We will discuss this issue further in this article And presenting a case study, a rapid method for evaluating such projects were presented. In this paper, first, the research literature and the different methods of the Visual evaluation will be presented. Then a combined approach using geographic information systems software capabilities (GIS) has been used in here. Case study is done on local quarries (Chegeni Region in Khorramabad), but techniques are generalizable to other projects.

Background: The research was done to evaluate the value of the Visual evoked potentials test in the assessment of Visual pathways function in cases with head trauma and minimal findings on routine testing. Materials and Methods: A prospective case series evaluating use of Visual evoked potentials testing in patients with a history of head trauma and suffering from Visual symptoms with no significant clinical and neuroimaging findings, referred for further work up. Results: Thirty-four patients with a history of head trauma and subsequent Visual complaints were included. 27 cases (79. 4%) were male and 7 cases (20. 6%) were female. The mean elapsed time after the trauma was 47. 6 weeks (range: 3. 5 to 320 weeks). Twenty-five cases had unilateral and 9 cases had bilateral Visual complaints. History of coma with mean duration of 12 days was present in 4 cases. The best-corrected Visual acuity was less than 1 Log MAR (legally blind) in 21 eyes. In 4 eyes (12%) the relative afferent papillary defect test was positive. Mild to moderate optic disc pallor was present bilaterally in 4 cases and unilaterally in 3 cases. Hemorrhagic patches were reported on MRI in 2 cases; no other cases had pathologic MRI findings. In unilateral cases, there was a statistically significant difference between the involved eye-sided lobe and the sound eye-sided lobe implicit time and amplitude. In patients with bilateral complaints, by testing each eye, the VEP amplitudes of both eyes showed significant differences with the International Society for Clinical Electrophysiology of Vision standards, whereas the implicit times showed not-statistically significant differences. Conclusion: The Visual evoked potentials test shows not only additional diagnostic value, not seen on routine clinical and neuroimaging testing, but also rather a high validity in tracing Visual disability in traumatic brain injury.