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Background & Objective: Due to volatile property of monomer from Methylmethacrylate and its well known toxic side effects, in case of absorption via skin or respiratory system. Also, due to allergic reactions of it, consideration of suitable ventilation systems and using protective methods is very important. To decrease direct contact with it, the capabilities of technician and improves his health and work place, we investigate relationship between Methanol level and exposure to Methylmethacrylate. Materials & Methods: In a case-control (In vivo) study of 32 dental laboratory technicians in Babol and Sari before and after working and 32 normal subjects, urine samples were collected. Urine Methanol levels were analyzed by paper and gas chromatography. Results: Mean concentration of Methanol in case group (1.2 micro mol/l) was significantly more than control group (0.78 micro mol/l). Also, Methanol level was significantly higher after work (1.45 micro mol/l) when compared to before work (1.27 micro mol/l), (P<0.05). No relation between work history and urine Methanol level was observed. Conclusion: Due to significant increase of Methanol concentration during work in work place, the use of protective methods such as suitable ventilation, wearing mask and gloves, also, using vapor absorbing tubes can be useful in increasing dental laboratory workplace safety.

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Background and Objective: Gait is a fundamental movement pattern influenced by various structures. This study aimed to determine the effect of sand-based training on ground reaction force frequency spectrum in individuals with anterior cruciate ligament (ACL) reconstruction and pronated feet during gait.
Methods: This clinical trial was conducted on 28 male students with pronated feet and ACL injuries aged 22-25 years at Mohaghegh Ardabili University. Participants were randomly assigned to two groups of 14: A control group and a sand-based training group. The ground reaction force variables were measured using a force plate in the pre-test and post-test.
Results: The number of necessary harmonics in the free moment component decreased by 15.95% in the post-test (16.48±4.14) compared to the pre-test (19.11±2.15) of the control group (P<0.05). The number of necessary harmonics in the mediolateral direction of the ground reaction force decreased by 23.34% in the post-test (15.59±3.92) compared to the pre-test (19.23±2.66) of the training group (P<0.05). Additionally, the number of necessary harmonics in the anteroposterior direction of the ground reaction force increased by 33.04% in the post-test (21.61±2.55) compared to the pre-test (14.47±4.11) of the training group (P<0.05).
Conclusion: Sand-based training was able to improve the gait mechanics of individuals with ACL reconstruction and pronated feet.