Repetition Improves Precision and Trueness of Digital Intraoral Scans
Condition: Tooth Diseases
MeSH terms: Tooth Diseases
Study type: Interventional

Summary: 
      The objectives of this study were to compare the precision of two digital intraoral scanners
      from a series of repeat scan images, and to investigate the effect of the learning curve on
      changes in trueness when scanning the full arch of the oral cavity in actual patients.
    

Detailed description: 
      Study Participants: This study was approved by the institutional review board of Ehwa Womans
      University Medical Center Mokdong Hospital, and dental hygienists who were suitable for the
      purpose of the study were selected (ECT14-02A-27). Participants were assigned one of four
      patients, and subsequently scanned the oral cavity of a single patient 10 times repeatedly
      over 4 days.

      Study Design: The participants visited the dental clinic and performed scanning for 4 days.
      In order to investigate the difference in the precision and trueness of two types of
      intraoral scanners, the participants scanned the dental arch of a single patient 10 times
      using an assigned digital intraoral scanner. On the first day, either of the two types of
      scanners (iTero and Trios), and a patient were assigned. Then, the participants were trained
      in theory and practices of the assigned scanner, and subsequently, using it, scanned the
      dental arch of the assigned patient twice. On the second and third days, the dental arch of
      the same patient was scanned 3 times respectively, and on the fourth day, the experiment was
      finished after scanning the same patient twice.

      Statistical Analyses: Collected data were analyzed using the SPSS Ver. 20.0 statistical
      package. For the determination of differences in the deviations according to the scanner, the
      independent two-sample t-test was conducted to examine the significance of the precision
      data. For comparisons of trueness according to repeated learning, the repeated measure ANOVA
      was used to test for differences between the scanners, clinical experience of the
      participants, and the scanning region within the same scanner group. The significance of
      time-dependent changes, and the interaction between the scanner group and time variables,
      were examined by within-subject tests. Differences between the scanner groups were examined
      by between-subject tests. The significance of the 10 consecutive scans and four visits within
      the scanner group, and the difference between the scanner groups at each time point, were
      examined by the post-hoc test, which was performed using the Bonferroni method as a multiple
      comparison (α= 0.05).
    

Intervention name(s): impression data from reference scanner; iTero; Trios
Intervention type(s): Other; Device; Device
Intervention description(s): To create a reference images for the assessment of the trueness, the impressions of the upper and lower arch of the oral cavities of four patients were taken using a polyether impression material (3M ESPE Soft Monophase; Minnesota Mining and Manufacturing Co.), and the intaglio scanning was performed on the impression body using a desktop scanner. Scanned images were transformed to the Standard Tessellation Language (STL) file format, and used as reference images.; The participants visited the dental clinic and performed scanning for 4 days. In order to investigate the difference in the precision and trueness of iTero intraoral scanners, the participants scanned the dental arch of a single patient 10 times using an assigned digital intraoral scanner.; The participants visited the dental clinic and performed scanning for 4 days. In order to investigate the difference in the precision and trueness of Trios intraoral scanners, the participants scanned the dental arch of a single patient 10 times using an assigned digital intraoral scanner. .
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Health Services Research
Keywords: CAD; Digital imaging; Prosthetic Dentistry