IADR Abstract Archives
Effect of Magnification Devices on Visual Acuity in Dental Students
Objectives: This study aimed to observe the visual acuity of dental students when using five different magnification devices (natural vision, simple loupes, Galilean loupes, Keplerian loupes and operating microscope) in two different working distances (recommended distance of 35 cm and free choice).
Methods: The sample was composed of students from 2nd to 5th years of São Paulo State University, Araraquara Dental School (N=160). The visual acuity was evaluated using miniaturized visual tests, fixed in the occlusal cavity in maxillary first molar of a dental phantom. Initially, the test was conducted at the recommended distance, followed to the operator’s free choice, except for the operating microscope that was kept at a same distance according to the height of each student, in order to maintain a proper focus. After verified the normality and homoscedasticity assumptions, the two-way Analysis of Variance (ANOVA) was conducted, followed by the Games Howell pos hoc. The data analysis was conducted independently for the different years of the course (2nd, 3rd, 4th and 5th). The significance level was set at 5%.
Results: A significant difference was observed in the interaction between the magnification system and distance factors (p <0.01) for all the years of the course. The simple loupes in the standardized distance presented the lowest visual acuity (μ=10.94±38.90-32.81±106.64) and the Galilean, Keplerian and Operative Microscope systems presented the highest visual acuity, however, no statistically significant difference in the distance of evaluation (444.79±238.03-583.33±0.00).
Conclusions: It was concluded that the best visual acuity could be achieved with the use of the Galilean, Keplerian and Operative Microscope magnification systems.
Methods: The sample was composed of students from 2nd to 5th years of São Paulo State University, Araraquara Dental School (N=160). The visual acuity was evaluated using miniaturized visual tests, fixed in the occlusal cavity in maxillary first molar of a dental phantom. Initially, the test was conducted at the recommended distance, followed to the operator’s free choice, except for the operating microscope that was kept at a same distance according to the height of each student, in order to maintain a proper focus. After verified the normality and homoscedasticity assumptions, the two-way Analysis of Variance (ANOVA) was conducted, followed by the Games Howell pos hoc. The data analysis was conducted independently for the different years of the course (2nd, 3rd, 4th and 5th). The significance level was set at 5%.
Results: A significant difference was observed in the interaction between the magnification system and distance factors (p <0.01) for all the years of the course. The simple loupes in the standardized distance presented the lowest visual acuity (μ=10.94±38.90-32.81±106.64) and the Galilean, Keplerian and Operative Microscope systems presented the highest visual acuity, however, no statistically significant difference in the distance of evaluation (444.79±238.03-583.33±0.00).
Conclusions: It was concluded that the best visual acuity could be achieved with the use of the Galilean, Keplerian and Operative Microscope magnification systems.