Diagnostic accuracy of impression-free digital models.

INTRODUCTION Impression-free techniques might eliminate the potential shortcomings of digital dental models. Chairside scanners offer the advantage of obtaining digital dental models directly from the patient without the need for dental impressions. The aim of this study was to evaluate the accuracy of 3-dimensional digital models acquired from a chairside intraoral scanner compared with both manual and cone-beam computed tomography measurements of the same dental anatomy. METHODS The study sample comprised 60 dry skulls. Each skull had the maxillary and mandibular arches scanned with a Cadent iTero scanner (Align Technology, San Jose, Calif) and had a cone-beam computed tomography scan taken with a CS 9300 unit (Carestream Health, Atlanta, Ga). Linear measurements in all 3 dimensions of the space in each dental arch together with tooth-size arch-length analysis for both the maxillary and mandibular arches were carried out manually on the dry skulls with calipers and digitally on the scanned 3-dimensional models and cone-beam computed tomography images. Intraclass correlation (ICC) analysis was performed for all variables tested in the study groups, with the manual measurements on the dry skulls as the gold standard. The Bland-Altman analysis was also applied to the data to graphically display the agreement of the diagnostic measurements obtained from these methods. RESULTS Measurements from the iTero models demonstrated near-perfect agreement (ICC, 0.91-0.99) with the caliper measurements. Cone-beam computed tomography measurements had moderate to high levels of agreement (ICC, 0.65-0.99) compared with the caliper measurements. CONCLUSIONS Direct digital acquisition of the dental arches with a chairside scanner provided almost 1-to-1 diagnostic information of the investigated anatomy and was superior to the cone-beam computed tomography measurements.

[1]  M. Goonewardene,et al.  Accuracy and validity of space analysis and irregularity index measurements using digital models. , 2008, Australian orthodontic journal.

[2]  James Mah,et al.  The evolution of digital study models. , 2007, Journal of clinical orthodontics : JCO.

[3]  J. Fischer,et al.  A comparison of 3 computerized Bolton tooth-size analyses with a commonly used method. , 2009, The Angle orthodontist.

[4]  Mark G Hans,et al.  Accuracy and reliability of cone-beam computed tomography for measuring alveolar bone height and detecting bony dehiscences and fenestrations. , 2010, American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics.

[5]  Roberto Carrillo,et al.  Accuracy and reliability of tooth and root lengths measured on cone-beam computed tomographs. , 2010, American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics.

[6]  F. Qian,et al.  Accuracy of linear measurement in the Galileos cone beam computed tomography under simulated clinical conditions. , 2011, Dento maxillo facial radiology.

[7]  Shin Kim,et al.  ACCURACY OF CONE-BEAM COMPUTED TOMOGRAPHY IN PREDICTING THE DIAMETER OF UNERUPTED TEETH , 2012 .

[8]  Lapo Governi,et al.  A Comparative Analysis Of Intraoral 3d Digital Scanners For Restorative Dentistry , 2008 .

[9]  R. Cibrián,et al.  A comparison between dental measurements taken from CBCT models and those taken from a digital method. , 2013, European journal of orthodontics.

[10]  A. Mehl,et al.  Full arch scans: conventional versus digital impressions--an in-vitro study. , 2011, International journal of computerized dentistry.

[11]  Accuracy of digital and conventional impression techniques and workflow , 2013, BDJ.

[12]  Raphael Patcas,et al.  Accuracy of cone-beam computed tomography at different resolutions assessed on the bony covering of the mandibular anterior teeth. , 2012, American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics.

[13]  Janalt Damstra,et al.  Accuracy of linear measurements from cone-beam computed tomography-derived surface models of different voxel sizes. , 2010, American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics.

[14]  Thomas J Cangialosi,et al.  Comparison of space analysis evaluations with digital models and plaster dental casts. , 2009, American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics.

[15]  A. Jacobson,et al.  An evaluation of the use of digital study models in orthodontic diagnosis and treatment planning. , 2009, The Angle orthodontist.

[16]  A. Johal,et al.  Orthodontic measurements on digital study models compared with plaster models: a systematic review. , 2011, Orthodontics & craniofacial research.

[17]  Peter Ngan,et al.  Accuracy of space analysis with emodels and plaster models. , 2007, American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics.

[18]  D. Altman,et al.  Measuring agreement in method comparison studies , 1999, Statistical methods in medical research.

[19]  Allen R Firestone,et al.  The accuracy and reliability of measurements made on computer-based digital models. , 2009, The Angle orthodontist.

[20]  Chung How Kau,et al.  Digital models vs plaster models using alginate and alginate substitute materials. , 2010, The Angle orthodontist.

[21]  J Martin Palomo,et al.  Reliability and accuracy of cone-beam computed tomography dental measurements. , 2009, American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics.

[22]  Manuel O Lagravère,et al.  Three-dimensional accuracy of measurements made with software on cone-beam computed tomography images. , 2008, American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics.

[23]  F Garino,et al.  The iOC intraoral scanner and Invisalign: a new paradigm. , 2012, Journal of clinical orthodontics : JCO.

[24]  Paul W Major,et al.  Validity, reliability, and reproducibility of plaster vs digital study models: comparison of peer assessment rating and Bolton analysis and their constituent measurements. , 2006, American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics.

[25]  P. Campos,et al.  Accuracy of Linear Measurements in Cone Beam Computed Tomography With Different Voxel Sizes , 2012, Implant dentistry.

[26]  C. Kau,et al.  Surface analysis of study models generated from OrthoCAD and cone-beam computed tomography imaging. , 2012, American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics.