OBJETIVE: The objective of this study was to evaluate the effects of magnification on the quality of two pre-clinical procedures, class I cavity preparations and composite resin restorations, and to evaluate the working posture. METHODS: This was an experimental laboratory study. The response variables were the quality of cavity preparations and Class I restorations as well as the working posture adopted during the execution of these procedures. The independent variables were the magnification system under four levels (unaided visualization, the use of a simple loupe, the use of a Galilean loupe, and the use of a Keplerian loupe) and the artificial teeth treated. Class I cavity preparations and restorations (N=320) were performed using standardized procedures, and the quality achieved was evaluated using pre-established criteria. Working posture was recorded using digital video cameras and was evaluated using the Compliance Assessment of Dental Ergonomic Posture Requirements (CADEP). A two-factor analysis of variance (ANOVA) and multiple comparison test were performed (α=0.05). RESULTS: The quality of cavity preparation did not differ significantly among the different magnification systems (p=0.082). Galilean and Keplerian systems had a positive impact on restoration quality only for the left mandibular first molar (p=0.04). Higher posture scores were observed when Galilean and Keplerian loupes (p=0.01) were used, regardless of the tooth being treated. CONCLUSION: The use of Galilean and Keplerian magnification lenses did not affect the quality of the pre-clinical procedures performed while improved the scores of ergonomic posture. This article is protected by copyright. All rights reserved.
OBJETIVE: The objective of this study was to evaluate the effects of magnification on the quality of two pre-clinical procedures, class I cavity preparations and composite resin restorations, and to evaluate the working posture. METHODS: This was an experimental laboratory study. The response variables were the quality of cavity preparations and Class I restorations as well as the working posture adopted during the execution of these procedures. The independent variables were the magnification system under four levels (unaided visualization, the use of a simple loupe, the use of a Galilean loupe, and the use of a Keplerian loupe) and the artificial teeth treated. Class I cavity preparations and restorations (N=320) were performed using standardized procedures, and the quality achieved was evaluated using pre-established criteria. Working posture was recorded using digital video cameras and was evaluated using the Compliance Assessment of Dental Ergonomic Posture Requirements (CADEP). A two-factor analysis of variance (ANOVA) and multiple comparison test were performed (α=0.05). RESULTS: The quality of cavity preparation did not differ significantly among the different magnification systems (p=0.082). Galilean and Keplerian systems had a positive impact on restoration quality only for the left mandibular first molar (p=0.04). Higher posture scores were observed when Galilean and Keplerian loupes (p=0.01) were used, regardless of the tooth being treated. CONCLUSION: The use of Galilean and Keplerian magnification lenses did not affect the quality of the pre-clinical procedures performed while improved the scores of ergonomic posture. This article is protected by copyright. All rights reserved.