The awkward and repetitive movements lead to tissue straining, potentially leading to painful musculoskeletal disorders (MSDs). MSDs in dentists result in work inefficiency and a reduction in work hours. A survey was conducted to assess the prevalence of MSDs amongst the dental population of interest. Customized individual detail questionnaires, Standard Nordic Musculoskeletal questionnaires, and Level of Pain estimation using the Likert Scale were used to deduce the various responsible risk factors for the occurrence of MSDs in dentists. Inferential statistical analysis was done to identify the prevalence and severity of the MSDs. The Chi-Square test (95 % confidence interval) was used to identify and compare the association of risk factors involved in MSDs with the occurrence of the Effect of MSDs, the presence of MSDs, and the severity of the MSDs. The results of the study deduced that the dentists followed the sedentary work practices. The dentists experienced maximum discomfort in the neck region, which was accompanied by the discomfort experienced in the lower back, hands and wrists, making the upper extremity being more susceptible to the MSDs. Gender risk factors the, the prevalence of MSDs in the dentist's upper back, and the severity of pain in the upper back region showed a significant association level. The wrist posture, the prevalence of MSDs and the severity of pain in the dentists' neck, shoulder and upper back showed a significant association level.
8 September 2022 in International Journal on Interactive Design and Manufacturing (IJIDeM)
Burnishing is a cold working technique used as a surface enrichment to meet the desired surface properties of the workpiece. It improves the visual properties, dimensional tolerances, fatigue strength, surface roughness, and hardness of the work material by applying appropriate pressure through a complex ball burnishing tool to cause plastic deformation. In the current work, the mathematical modeling of the burnishing process was carried out to predict surface roughness by considering the process parameters such as contact radius, penetration depth, and elastic rebound. Further, a customized tungsten carbide (W.C.) insert having a hardness of 80 HRC was developed for the burnishing operation. The micro-hardness of the resulting burnished surface improved from 44 to 48 HRC. The surface quality of the tungsten carbide insert improved by up to 17.1 nm through polishing. Several experiments were performed by selecting appropriate process parameters using developed model feedback. The surface quality of the workpiece improved by up to 45 nm, which resulted in automatic improvements in fatigue strength up to seven times that of the virgin material. The results predicted from the mathematical model were in good agreement (less than 5% deviation) with the experimental results. This study helps to understand the surface formation mechanism in the burnishing process in more detail. Additionally, the achieved results show a significant improvement in the surface finish (~95%), indicating the potential of the burnishing process and how fast and cost-effective it is. The novelty of this paper lies in the improvement in surface roughness and the validation of our mathematical model results with the experimental results.