2 research outputs found

    Morphology of the Roots and Canals of Mandibular Third Molars, Their Symmetry and Related Factors Using Cone-Beam Computed Tomography

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    Introduction: Adequate knowledge about the anatomy of the roots and canals of mandibular third molars is imperative for a successful treatment. This study aimed to use cone-beam computed tomography (CBCT) to evaluate the morphology of the roots and canals of mandibular third molars and their symmetry. Methods and Materials: Totally, 110 CBCT images of bilateral mandibular third molars were evaluated in terms of the number of roots and canals, canal type, isthmus location, location of accessory canals, degree of root curvature and its direction, age and sex of patients and the symmetry of variables in the right and left sides of the mandible. The descriptive statistics, t-test and chi-square test were applied to analyze data. Results: Of all, 71.36% of mandibular third molars had two roots, 20.9% had one single root and 7.72% had three roots. The distal root had one single canal in 89.08%. The mesial root had one single canal in 44.25% and two canals in 49.42%. The Vertucci’s types I (45.40%) and IV (34.48%) had the highest frequency in the mesial root while type I (91.95%) had the highest frequency in the distal root. The deviation of mesial root was towards the distal while distal roots were mainly straight. Conclusion: The symmetry between the right and left mandibular third molars was significantly high. In case of encountering anatomical complexities in dental treatment of a mandibular third molar, dental clinicians should consider the high possibility of presence of the same condition in the contralateral mandibular third molar.Keywords: Anatomy; Cone-Beam Computed Tomography; Mandible; Third Mola

    Analytical Evaluation of Water Quality of Swimming Pools in The Southern Regions of Tehran in 2019

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    The water used in swimming pools, like drinking water, must comply with the required quality. Failure to comply with the physical, chemical and biological criteria of the pools will lead to health hurt to swimmers. In this cross-sectional paper carried out with a descriptive-analytical approach in the summer of 2019, 23 public and private pools located in the south of Tehran (districts 18 and 19) were selected. Pool water sampling was performed to determine microbial indices including thermophilic coliforms, heterotrophic plate count (HPC), and physicochemical parameters including turbidity, pH and residual chlorine. Then, each of the studied parameters was assigned a weight based on their importance and their status was analyzed by water quality index. Based on the findings, the microbial indices of thermophilic coliforms and HPC in the water of the sampled pools were at the desired level in 74 and 26.1% of samples, respectively. Regarding turbidity, pH and residual chlorine content in 13.1, 60.9 and 47.9% of the samples, were at the acceptable values, respectively. The results also showed that none of the sampled water was in excellent condition and 68% of the samples were in fair condition in terms of water quality. According to the obtained results, the necessity of continuous sampling of pool water to check their quality and effective interventions and finally the imposition of fines is suggested for those which their quality is not in accordance with the standards