[Assessment of color matching ability among the student of Yazd faculty of dentistry]

One of the most challenging procedures in restorative dentistry is fitting the color of the restoration to the tooth. The main purpose of this study was to determine the ability rate of color matching among the students of Yard faculty of dentistry in December 2004. In this descriptive study, 127 dental clinical students of Yard faculty were participated. Age, gender, wearing eyeglasses or lens and the year of starting the dental faculty were assessed as variable. Heliomolar composite with 16 colors was used to make the shade guide and 6 colors of the same composite were used as test group. The students were matched the shade guide with the test group in similar conditions. The data was analyzed by t, ANOVA and LSD test. Mean truth definition of all colors in 20-29 years old students were 3.86 and in 30-40 years old group were 3.38 and there was no significant differences between them. Mean truth definition in male group was 3.57 and was 3.91 in females. There was no significant differences between them. Mean truth definition in all of the colors by students without eyeglasses or contact lens were 3.98 and the other group was 3.55 which was significantly differences [P=0.023]. The difference between the entrance year for mean truth definition of all colors was significant [P=0.016]. In this study, the students whom specially wear photochoromic eyeglasses or contact lenses were lower truth color definition, but age and gender had no effect on truth color definition

Quality and quantity survey of hospital wastewaters in hormozgan province

Hospital wastewaters are one of the most contaminating wastewaters and need to be paid more attention due to containing infectious agents. In this study, which had been conducted in a period of one year, 7 public hospitals were selected out of 12 public hospitals in Hormozgan Province of Iran. For studying quality of wastewater in hospitals, both influent and effluent wastewaters of treatment plant, if any, were sampled once in each season and totally 30 mixed samples were obtained. In order to determine the quality of hospital wastewaters in all samples, parameters such as pH, BOD[5], COD, TSS and temperature were measured. Results of investigation on annual water consumption indicated that average water consumption in hospitals of the province was 194m[3]/d., considering water-to-wastewater conversion ratio of 0.8 and green yard ratio of 0.3. Wastewater production rate had been estimated to be 47m[3]/d and 0.362 m[3]/d.bed. Results indicated that in 7 hospitals of Hormozgan province, mean values of BOD[5], COD, TSS in raw wastewater were 242.25 mg/L, 628.1 mg/L and 231.25 mg/L, respectively, pH=7.42 and temperature=30.17 °C. In Khalij-e-Fars hospital which had wastewater treatment plant, values of these parameters in effluent were 12.53 mg/L and 51.7 mg/L, 19.68 mg/L, respectively, with pH=7.39 and temperature=26.1 °C. Comparison between values of influent and effluent wastewaters indicated that in understudy cases, contamination rate was higher than determined limits, as compared to environmental standards of the country and it was necessary to establish appropriate treatment plants in these units