In vivo accuracy of tooth surface reconstruction based on CBCT and dental MRI—A clinical pilot study

Abstract

Objectives Guided implant surgery (GIS) requires alignment of virtual models to reconstructions of three‐dimensional imaging. Accurate visualization of the tooth surfaces in the imaging datasets is mandatory. In this prospective clinical study, in vivo tooth surface accuracy was determined for GIS using cone‐beam computed tomography (CBCT) and dental magnetic resonance imaging (dMRI). Materials and methods CBCT and 3‐Tesla dMRI were performed in 22 consecutive patients (mean age: 54.4 ± 15.2 years; mean number of restorations per jaw: 6.7 ± 2.7). Altogether, 92 teeth were included (31 incisor, 29 canines, 20 premolars, and 12 molars). Surfaces were reconstructed semi‐automatically and registered to a reference standard (3D scans of stone models made from full‐arch polyether impressions). Reliability of both methods was assessed using intraclass correlation coefficients. Accuracy was evaluated using the two one‐sided tests procedure with a predefined equivalence margin of ±0.2 mm root mean square (RMS). Results Inter‐ and intrarater reliability of tooth surface reconstruction were comparable for CBCT and dMRI. Geometric deviations were 0.102 ± 0.042 mm RMS for CBCT and 0.261 ± 0.08 mm RMS for dMRI. For a predefined equivalence margin, CBCT and dMRI were statistically equivalent. CBCT, however, was significantly more accurate (p ≤ .0001). For both imaging techniques, accuracy did not differ substantially between different tooth types. Conclusion Cone‐beam computed tomography is an accurate and reliable imaging technique for tooth surfaces in vivo, even in the presence of metal artifacts. In comparison, dMRI in vivo accuracy is lower. Still, it allows for tooth surface reconstruction in satisfactory detail and within acceptable acquisition times.

Use of dental MRI for radiation-free guided dental implant planning: a prospective, in vivo study of accuracy and reliability

“…For registration in implant planning, tooth surfaces are commonly used. The errors for in vivo tooth surface reconstructions derived from dental MRI and CBCT (mean error ± root mean square of dental MRI and CBCT 0.26 ± 0.1 and 0.1 ± 0.04 mm, respectively) were reported in a recent study [19]. This explains, at least in part, why accuracy was lower in our study than in Kühl et al…”

“…This study has several methodological strengths. First, it made use of a previously established technique to visualize tooth surfaces within dental MRI [ 19 ]. As a result, it was possible to integrate dental MRI into an existing digital workflow without the need for additional software or time-consuming postprocessing steps.…”

“…2). To enable accurate segmentation of tooth surfaces in MRI data, a splint technique was used during the dental MRI examination, as described previously [19]. DICOM data from the dental MRI and STL data from the digitalized stone cast (D2000, 3shape) were subsequently imported and co-registered in an established software program for guided implant surgery (coDiagnostiX 9.12, Dental Wings Inc.).…”

Facial Alveolar Bone Thickness and Modifying Factors of Anterior Maxillary Teeth: A Systematic Review and Meta-Analysis of Cone-Beam Computed Tomography Studies

“…Besides, CEJ anatomical reference registration is usually di cult, though its impact on bone height measurements is to be around 0.01 mm, this is a lower difference than obtained with cusp tip (0.1 mm) as landmark [62]. These values are lower than the maximum errors reported for CBCT-derived tooth surfaces measures in vivo (± 0.2 mm) [63]. Also, this measurement variability at tooth surfaces level with CBCT, in vivo, is not that different from those observed for FAB thickness at CI, LI and C. In the present work, FAB measurement standard deviations in CI, LI, and C were around (± 0.2 to ± 0.29 mm)…”

Comparison of non‐contrast‐enhanced dental magnetic resonance imaging and cone‐beam computed tomography in assessing the horizontal and vertical components of furcation defects in maxillary molars: An in vivo feasibility study

“…In recent years, considerable technical advances have been made in the development and implementation of in vivo dental magnetic resonance imaging (dMRI) techniques (Hilgenfeld et al, 2017(Hilgenfeld et al, , 2018(Hilgenfeld et al, , 2019Juerchott et al, 2019;Ludwig et al, 2016;Sedlacik et al, 2016;Tymofiyeva et al, 2010). Recently, it was shown that a dMRI technique using intravenous gadolinium-based contrast agent (GBCA) enables the detection and classification of horizontal furcation defects in maxillary molars with high reliability and accuracy in vivo (Juerchott et al, 2020).…”