Do Different Brands of Dental Loupes and their Magnification Influence Working Posture and the Quality of Tooth Preparations?

Aims: This study aimed to assess the effect of different commercial brands of dental loupes and their magnification systems on the working posture and quality of preclinical tooth preparations. Methodology: An experimental laboratory study was conducted. The response variables were: 1) angular deviation of the neck; 2) working distance; and 3) quality of tooth preparation. The independent variables were the dental loupe brands (LumaDent, Design for Vision, Univet and Q-Optics) and type of magnification (naked eye, Galilean 2.5x, Galilean 3.0x and Ergonomic 3.0x). Class I tooth preparations were performed on artificial maxillary left-first molars in a dental mannequin (n=10, N=110). Angular deviations were measured using the Software for Postural Assessment and the working distance was measured using the Measure App. The quality of tooth preparations was assessed using the Class One Cavity Preparation Assessment method. Descriptive statistics were performed, and after verifying the assumptions, confidence intervals were created allowing comparisons between the means (α=.05). Results: All magnification systems, regardless of their brands, promoted a greater working distance and a lower angular deviation of the neck compared to the naked eye. The Ergonomic loupes offered greater working distance and reduced angular deviation compared to the Galilean loupes. There was no statistical difference between both the Ergonomic loupes tested and among all the Galilean loupes tested. The quality of the tooth preparations was similar when done with naked eye and all magnification systems, regardless of their brands. Conclusion: The working posture was more affected by the type of magnification system used, rather than their commercial brands. Ergonomic loupes, regardless their brands, provided the lowest angular deviation of the neck and the longest working distance, improving significantly the working posture. The quality of the tooth preparations was not affected by the dental loupe brands and their magnification systems.