Marta Revilla-León1, Peng Jiang2, Mehrad Sadeghpour3, Wenceslao Piedra-Cascón4, Amirali Zandinejad5, Mutlu Özcan6, Vinayak R Krishnamurthy7. 1. Assistant Professor and Assistant Program Director AEGD Residency, College of Dentistry, Texas A&M University, Dallas, Texas; Affiliate Faculty Graduate Prosthodontics University of Washington, Seattle, Wash; Researcher, Revilla Research Center, Madrid, Spain. Electronic address: revillaleon@tamhsc.edu. 2. Graduate Research Assistant, Mechanical Engineering, Texas A&M University, College Station, Texas. 3. Private practice, Dallas, Texas. 4. Affiliate Faculty Graduate in Esthetic Dentistry, Complutense University of Madrid, Madrid, Spain; Researcher, Revilla Research Center, Madrid, Spain. 5. Associate Professor and Program Director AEGD Residency, College of Dentistry, Texas A&M University, Dallas, Texas. 6. Professor and Head, Dental Materials Unit, Center for Dental and Oral Medicine, University of Zürich, Zürich, Switzerland. 7. Assistant Faculty Mechanical Engineering, Texas A&M University, College Station, Texas.
Abstract
STATEMENT OF PROBLEM: Digital scans have increasingly become an alternative to conventional impressions. Although previous studies have analyzed the accuracy of the available intraoral scanners (IOSs), the effect of the light scanning conditions on the accuracy of those IOS systems remains unclear. PURPOSE: The purpose of this in vitro study was to measure the impact of lighting conditions on the accuracy (trueness and precision) of different IOSs. MATERIAL AND METHODS: A typodont was digitized by using an extraoral scanner (L2i; Imetric) to obtain a reference standard tessellation language (STL) file. Three IOSs were evaluated-iTero Element, CEREC Omnicam, and TRIOS 3-with 4 lighting conditions-chair light 10 000 lux, room light 1003 lux, natural light 500 lux, and no light 0 lux. Ten digital scans per group were recorded. The STL file was used as a reference to measure the discrepancy between the digitized typodont and digital scans by using the MeshLab software program. The Kruskal-Wallis, 1-way ANOVA, and pairwise comparison were used to analyze the data. RESULTS: Significant differences for trueness and precision mean values were observed across different IOSs tested with the same lighting conditions and across different lighting conditions for a given IOS. In all groups, precision mean values were higher than their trueness values, indicating low relative precision. CONCLUSIONS: Ambient lighting conditions influenced the accuracy (trueness and precision) of the IOSs tested. The recommended lighting conditions depend on the IOS selected. For iTero Element, chair and room light conditions resulted in better accuracy mean values. For CEREC Omnicam, zero light resulted in better accuracy, and for TRIOS 3, room light resulted in better accuracy.
STATEMENT OF PROBLEM: Digital scans have increasingly become an alternative to conventional impressions. Although previous studies have analyzed the accuracy of the available intraoral scanners (IOSs), the effect of the light scanning conditions on the accuracy of those IOS systems remains unclear. PURPOSE: The purpose of this in vitro study was to measure the impact of lighting conditions on the accuracy (trueness and precision) of different IOSs. MATERIAL AND METHODS: A typodont was digitized by using an extraoral scanner (L2i; Imetric) to obtain a reference standard tessellation language (STL) file. Three IOSs were evaluated-iTero Element, CEREC Omnicam, and TRIOS 3-with 4 lighting conditions-chair light 10 000 lux, room light 1003 lux, natural light 500 lux, and no light 0 lux. Ten digital scans per group were recorded. The STL file was used as a reference to measure the discrepancy between the digitized typodont and digital scans by using the MeshLab software program. The Kruskal-Wallis, 1-way ANOVA, and pairwise comparison were used to analyze the data. RESULTS: Significant differences for trueness and precision mean values were observed across different IOSs tested with the same lighting conditions and across different lighting conditions for a given IOS. In all groups, precision mean values were higher than their trueness values, indicating low relative precision. CONCLUSIONS: Ambient lighting conditions influenced the accuracy (trueness and precision) of the IOSs tested. The recommended lighting conditions depend on the IOS selected. For iTero Element, chair and room light conditions resulted in better accuracy mean values. For CEREC Omnicam, zero light resulted in better accuracy, and for TRIOS 3, room light resulted in better accuracy.