Aa Yekta, C Dehghani, H Ostadi Moghaddam, J Heravian, E Jafarzadehpur, A Azimi, R Yekta, A Javaherforoshzadeh, M Pedramfar, B Rezvan, N Kiasatfard, M Khabazkhoob,
Volume 6, Issue 3 (11 2010)
Abstract
Background & Objective: Refractive errors (myopia, hyperopia and astigmatism) could lead to an impaired quality of life affect a large proportion of the population worldwide, irrespective of age, sex and ethnic group. Such refractive errors can be easily diagnosed, measured and corrected with spectacles or other refractive corrections to attain normal vision. Since there is paucity of information in school children in Iran we aimed to investigate the distribution pattern of refractive status and prevalence of refractive errors in school-age children in Shiraz
Methods: A random sampling strategy in geographically defined clusters was used to identify children aged 6-15 years in Shiraz between 2008-2209. We carried out a school survey and actual eye examinations, including visual acuity measurements, stereopsis examination, anterior segment and eyeball movements, fundus examinations, and cycloplegic retinoscopy with 1% cyclopentolate.
Results: Of 3065 selected individuals, 2683 were participated in the study (response rate 86.6%). According to cycloplegic refraction, 4.85% (95% (Cl), 3.52 to 6.16) of the primary and middle school students were myopic and 4.64% (95% Cl, 3.52 to 6.19) were hyperopic. For high school students, these rates were 22.19 and 11.4% respectively. Myopia and hyperopia were shown to be correlated with age. Prevalence of anisometropia, amblyopia and strabismus were 2.51%, 2.31(95%CI 1.51-3.11) and 1.83% (95%CI 1.15-2.50).
Conclusion: Compared to other published reports, the rate of myopia in the school children of Shiraz seems relatively high.
S Dehghani, A Abadi, M Namdari, Z Ghorbani,
Volume 14, Issue 4 (Vol.14, No.4, 2019)
Abstract
Background and Objectives: Periodontal disease is one of the most common oral health problems. Clinical attachment loss occurs in sever periodontal cases (CAL>3). In this study, we applied a classic regression model and the models that consider the hierarchical structure of the data to estimate and compare the effect of different factors on CAL.
Methods: This cross-sectional study was performed in 375 pregnant women and 192 mothers of three-year-old children. The data were gathered from 16 health networks of Shahid Beheshti University of Medical Sciences, Tehran, Iran. CAL was determined for 6 teeth per person by a dentist according to WHO standard oral health examination form. Three-level and ordinary logistic regression analyses were applied for data analysis using the STATA software 14.
Results: Of 3,402 examined teeth, 6.3% had CAL> 3mm. Based on the obtained results, the odds of CAL>3mm were 2.4 in the third semester compared to non-pregnant women. The odds of CAL>3mm were 2.86 in women without daily floss use compared to women with routine daily floss use. Posterior teeth were more likely to have CAL>3m than anterior teeth (OR = 1.65) (P-value < 0.05).
Conclusion: According to the AIC index, multi-level logistic regression model has a better fit than ordinary logistic regression model and can estimate the coefficients of factors related to CAL>3mm more precisely. The use of the ordinary logistic regression model in hierarchical data can result in underestimated standard errors of the estimated parameters.
Samaneh Dehghani, Masud Yunesian,
Volume 19, Issue 4 (Vol.19, No.4, Winter 2024)
Abstract
Microplastics refer to plastic particles and fragments smaller than 5 millimeters in various forms, derived from the breakdown of larger plastics or initially introduced into the environment from the primary constituent particles of plastic. The exact date of the emergence of microplastics in the environment is not precisely known, but it certainly predates the naming of these particles (2004). These particles can enter the bodies of living organisms, including humans, primarily through ingestion and inhalation. Their effects on the body depend on their size, chemical composition, and the composition of substances that later absorb these particles. In this article, we will first briefly examine the classification of these particles in terms of chemical composition and their origins, and then review some evidence of their presence in biological tissues and fluids. Given the increasing production and use of plastics in human life and the fact that most microplastics in nature derive from the breakdown of larger plastics, sometimes several years after their disposal, it is expected that even if plastic production decreases or stops, we will continue to see an increase in their presence in nature for years and decades, leading to human exposure to these compounds (whose effects and consequences of this exposure are not yet fully understood).