Effect of different types of dental stool on working posture, discomfort and productivity in dentistry.

• Grant number: 22/10084-6
• Support Opportunities: Scholarships in Brazil - Master
• Start date: November 01, 2022
• End date: March 31, 2024
• Field of knowledge: Health Sciences - Dentistry - Social and Preventive Dentistry
• Principal Investigator: Patrícia Petromilli Nordi Sasso Garcia
• Grantee: Júlia Carrer Hallak
• Host Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

This study aims to evaluate the effect of different dental stools on the working posture in Dentistry, measured by muscle activity, the risk of developing musculoskeletal disorders in the upper limbs, adherence to ergonomic posture requirements and the angular deviation of the neutral neck position, as well as discomfort, pain, and productivity while performing simulated Class I cavity preparation. For this, a laboratory experimental study will be carry out, where the dependent variables will be: 1) working posture evaluated by the muscular activity of the upper, abdominal and lower body regions; 2) risk of developing musculoskeletal disorders in the upper limbs; 3) adherence to ergonomic posture requirements; 4) angular deviation from neutral neck position; 5) the perception of discomfort and pain; 6) productivity during simulated cavity preparations. The independent variables will be: the type of dental stool used in three levels (conventional stool, saddle stool and SeatBall stool) and the working arc in 2 levels (upper and lower). Simulated Class I cavity preparations for composite resin will be performing with a spherical cutter diamond #1014 at low speed for 90 minutes in a row. For this, upper and lower arch simulator plates containing 8 drawings each will be used, simulating the Class I cavity preparation format, they will be fitted over the corresponding arch in the specific dental phantom head for simulated procedures at the laboratory level. As the 8 preparations of the phantom plate are completed, it will be replaced by another one, containing new Class I cavity preparation drawings, up to a total of 90 minutes of work. Muscle activity will be evaluated by thermography of the upper, abdominal and lower body regions. Thermographic images will be obtained in two moments: before the period of work with each dental stool (control) and immediately after each period (90 min). The risk of developing musculoskeletal disorders will be assessed by the Rapid Upper Limb Assessment - RULA method, which uses a diagram for assessing the individual's posture and three score tables that allow the assessment of exposure to risk factors for the development of musculoskeletal disorders, by means of the use of risk scores. To assess the working posture, the Compliance Assessment of Dental Ergonomic Posture Requirements - CADEP will be used. The recording of postures will be done through three-point filming throughout the procedure. For the analysis of the angular deviation, the "Software for Postural Assessment", version 0.69 will be used. The perception of discomfort and pain will be performed using the Visual Analog Scale (VAS Scale), where at the end of each procedure the operator will make a vertical line on the horizontal line of the VAS scale representing the amount of discomfort and pain perceived by him to execution of that procedure. For this, the beginning of the scale (zero point) should be considered as no discomfort and no pain, and the end (point ten) as maximum discomfort and maximum pain. This record will later be assigned a numerical value by measuring the zero point to the point recorded by the student using a millimeter ruler. The measurement of the working time (90 min) will be done with the help of a stopwatch. Productivity will be evaluated through the number of simulated preparations performed by the operator in the stipulated time (90 minutes) where, after the end of each period, the operator will fill in a form with the number of preparations performed. At the end of each period, the productivity will be calculated, which will be obtained by dividing the number of simulated preparations in the period by 90 minutes. Descriptive statistical analysis will be performed. After checking the normality assumptions and homoscedasticity will be performed two-way analysis of variance (ANOVA) and Tukey post-test. The significance level will be 5%.