title: A quantitative study of 3D-scanning frequency and Δd of tracking points on the tooth surface.
abstract: Micro-movement of human jaws in the resting state might influence the accuracy of direct three-dimensional (3D) measurement. Providing a reference for sampling frequency settings of intraoral scanning systems to overcome this influence is important. In this study, we measured micro-movement, or change in distance (∆d), as the change in position of a single tracking point from one sampling time point to another in five human subjects. ∆d of tracking points on incisors at 7 sampling frequencies was judged against the clinical accuracy requirement to select proper sampling frequency settings. The curve equation was then fit quantitatively between ∆d median and the sampling frequency to predict the trend of ∆d with increasing f. The difference of ∆d among the subjects and the difference between upper and lower incisor feature points of the same subject were analyzed by a non-parametric test (α = 0.05). Significant differences of incisor feature points were noted among different subjects and between upper and lower jaws of the same subject (P < 0.01). Overall, ∆d decreased with increasing frequency. When the frequency was 60 Hz, ∆d nearly reached the clinical accuracy requirement. Frequencies higher than 60 Hz did not significantly decrease Δd further.
authors.affiliation: Center of Digital Dentistry, Peking University School and Hospital of Stomatology, Faculty of Prosthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Research Center of Engineering and Technology for Digital Dentistry, Ministry of Health, 22 Zhongguancun Nandajie, Haidian District, Beijing 100081, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Li
authors.affiliation: Center of Digital Dentistry, Peking University School and Hospital of Stomatology, Faculty of Prosthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Research Center of Engineering and Technology for Digital Dentistry, Ministry of Health, 22 Zhongguancun Nandajie, Haidian District, Beijing 100081, China.
authors.forename: Peijun
authors.initials: P
authors.lastname: Lyu
authors.affiliation: Center of Digital Dentistry, Peking University School and Hospital of Stomatology, Faculty of Prosthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Research Center of Engineering and Technology for Digital Dentistry, Ministry of Health, 22 Zhongguancun Nandajie, Haidian District, Beijing 100081, China.
authors.forename: Yuchun
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Center of Digital Dentistry, Peking University School and Hospital of Stomatology, Faculty of Prosthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Research Center of Engineering and Technology for Digital Dentistry, Ministry of Health, 22 Zhongguancun Nandajie, Haidian District, Beijing 100081, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Beihang University, School of Instrumentation Science and Opto-electronics Engineering, Xue Yuan Road no. 37, Haidian District, Beijing 100191, China.
authors.forename: Xiaoyue
authors.initials: X
authors.lastname: Liang
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D009068:Movement; D014070:Tooth