C A Osnes1, J H Wu2, P Venezia3, M Ferrari4, A J Keeling5. 1. Department of Restorative Dentistry, School of Dentistry, University of Leeds, Leeds, United Kingdom; Department of Medical Biotechnologies, University of Siena, Siena, Italy. Electronic address: C.A.Osnes@leeds.ac.uk. 2. School of Dentistry, University of Leeds, Leeds, United Kingdom. 3. Department of Prosthodontics, School of Dental Medicine, University of Catania, Catania, Italy. 4. Department of Prosthodontics & Dental Materials, School of Dental Medicine, University of Siena, Siena, Italy; Dental Trial Clinical Research Unit [DenTCRU], School of Dentistry, University of Leeds, Leeds, United Kingdom. 5. Department of Restorative Dentistry, School of Dentistry, University of Leeds, Leeds, United Kingdom.
Abstract
PURPOSE: Intraoral scanners may offer an alternative to traditional impressions. That intraoral scanners produce precise scans is essential. Popular methods used to evaluate precision tend to rely on mean distance deviation between repeated scans. Mean value measurements may underestimate errors resulting in misleading conclusions and clinical decisions. This study investigated the precision of six intraoral scanners using the traditional method of measuring mean error, and a proposed method considering only the most extreme and clinically relevant aspects of a scan. METHODS: An edentulous model was scanned five times using six intraoral scanners. The repeated scans were aligned, uniformly trimmed and mean surface deviation measured across all 20 scan combinations within each scanner group. All scan combinations were then measured by arranging scan vertices from greatest to smallest unsigned distance from its compared scan and measuring the median value within the 1% of most greatly deviating points. Traditional mean deviation results and upper-bound deviations were compared. RESULTS: The upper-bound deviation within a scan reported errors up to two times greater than those found when measuring global mean distances. Results revealed clinically relevant errors of more than 0.3mm in scans produced by the Planmeca and Dentalwings scanners, findings not seen when measuring mean distance error of the complete scan. CONCLUSIONS: Upper-bound deviation of a cropped scan may provide a clinically useful metric for scanner precision. The Aadva, 3Shape, CEREC and TDS produced scans potentially appropriate for clinical use while Planmeca and Dentalwings produced deviations greater than 0.3mm when measuring the upper-bound deviation.
PURPOSE: Intraoral scanners may offer an alternative to traditional impressions. That intraoral scanners produce precise scans is essential. Popular methods used to evaluate precision tend to rely on mean distance deviation between repeated scans. Mean value measurements may underestimate errors resulting in misleading conclusions and clinical decisions. This study investigated the precision of six intraoral scanners using the traditional method of measuring mean error, and a proposed method considering only the most extreme and clinically relevant aspects of a scan. METHODS: An edentulous model was scanned five times using six intraoral scanners. The repeated scans were aligned, uniformly trimmed and mean surface deviation measured across all 20 scan combinations within each scanner group. All scan combinations were then measured by arranging scan vertices from greatest to smallest unsigned distance from its compared scan and measuring the median value within the 1% of most greatly deviating points. Traditional mean deviation results and upper-bound deviations were compared. RESULTS: The upper-bound deviation within a scan reported errors up to two times greater than those found when measuring global mean distances. Results revealed clinically relevant errors of more than 0.3mm in scans produced by the Planmeca and Dentalwings scanners, findings not seen when measuring mean distance error of the complete scan. CONCLUSIONS: Upper-bound deviation of a cropped scan may provide a clinically useful metric for scanner precision. The Aadva, 3Shape, CEREC and TDS produced scans potentially appropriate for clinical use while Planmeca and Dentalwings produced deviations greater than 0.3mm when measuring the upper-bound deviation.
Authors: Jaime Orejas-Perez; Beatriz Gimenez-Gonzalez; Ignacio Ortiz-Collado; Israel J Thuissard; Andrea Santamaria-Laorden Journal: Int J Environ Res Public Health Date: 2022-04-03 Impact factor: 3.390
Authors: Pietro Venezia; Ferruccio Torsello; Vincenzo Santomauro; Vittorio Dibello; Raffaele Cavalcanti Journal: Int J Environ Res Public Health Date: 2019-12-17 Impact factor: 3.390