Psychosocial Factors and Musculoskeletal Pain Among Rural Hand-woven Carpet Weavers in Iran

BACKGROUND: Musculoskeletal pain (MSP) is a common and disabling problem among carpet weavers and is linked to physical and psychosocial factors of work. This study aimed to determine the prevalence of MSP, its psychosocial risk factors, and association of pain in each pair of anatomical sites among carpet weavers. METHODS: A cross-sectional study was performed among 546 hand-woven carpet weavers in rural small-scale workshops of Iran. Data were collected by using parts of a standardized CUPID (Cultural and Psychosocial Influences on Disability) questionnaire focused on MSP in 10 body sites, including the low-back, neck, both right and left shoulders, elbows, wrists/hands, individual, physical and psychosocial risk factors. Statistical analysis was performed applying logistic regression models. RESULTS: Prevalence of MSP in at least one body site was 51.7% over the past month. The most common sites were low back and right shoulder pain 27.4% and 20.1%, respectively. A significant difference was found between the mean number of painful anatomical sites and the level of education, age, physical loading at work, time pressure, lack of support, and job dissatisfaction. In pairwise comparisons, strongest association was found between pain in each bilateral anatomical site (odds ratio = 11.6-35.3; p < 0.001). CONCLUSION: In home-based workshops of carpet weaving, psychosocial factors and physical loading were associated with MSP. This finding is consistent with studies conducted among other jobs. Considering the preventive programs, the same amount of attention should be paid to psychosocial risk factors and physical loading. Also, further longitudinal studies are needed to investigate the relationship of psychological factors.

[Fracture resistance of two different designs in fiber-reinforced composite restorations in mandibular anterior bridges: an in-vitro study]

The purpose of this study was to assess the fracture resistance of two different designs of tooth preparation and fiber placement in fiber-reinforced composite restorations replacing a missing mandibular lateral incisor. Forty newly extracted human mandibular intact teeth [20 centrals and 20 canines] were selected for fabrication of twenty FRC inlay bridges. A box preparation design with straight fibers, and a slot design preparation with curved fibers were implemented. After preparation, the teeth were mounted in self-cured acrylic resin with 6.5 mm distance from each other. PDL was simulated with polyether material. After taking impressions with polyether material, the impressions were poured with dental stone. The two groups of bridges were fabricated and bounded to teeth with panavia F[2]. The cyclic load of 1.2 x 10[6] x 20N x 1.66HZ was applied with 130° angle. The samples were stored in 37°C water for seven days and then thermo cycled [2000 cyles, 5-55°C]. The fracture strength was tested by a universal testing machine [Instron 1195] at a speed of 1 mm/min. The mode of fracture was observed under stereomicroscope. The data was analyzed by using independent sample T-test. The mean fracture resistance for the box design and direct fiber group was 1411.07 N and in the slot and curved fibers group was 377.33 N. The group difference was statistically significant [P=0.012]. It could be concluded that in fiber-reinforced composite restorations, box design with straight fiber has more fracture resistance than slot design with curved fiber