Clinical use of a direct chairside oral scanner: an assessment of accuracy, time, and patient acceptance

Am J Orthod Dentofacial Orthop. 2014 Nov;146(5):673-82. doi: 10.1016/j.ajodo.2014.07.023. Epub 2014 Oct 28.


Introduction: Chairside oral scanners allow direct digital acquisition of the intraoral situation and can eliminate the need for conventional impressions. In this study, we aimed to assess accuracy, scan time, and patient acceptance of a chairside oral scanner when used for full-arch scans; these are critical factors for acceptance of this technology in the orthodontic setting.

Methods: Fifteen patients had digital models made from both intraoral scans (Lava COS; 3M ESPE, St Paul, Minn) and alginate impressions. Each procedure was timed, and patient preference was assessed with a survey. In addition, digital models were made from 5 plaster model pairs using the intraoral scanner and an orthodontic model scanner. Model pairs were digitally superimposed, and differences between models were quantified. Accuracy was assessed using the Bland-Altman method. Time differences were tested for statistical significance with the Student t test.

Results: Digital models made using the chairside oral scanner and either impressions or the orthodontic model scanner did not differ significantly. The chair time required to take impressions was significantly shorter than the time required for the intraoral scans. When processing time was included, the time requirement did not differ significantly between methods. Although 73.3% of the patients preferred impressions because they were "easier" or "faster," 26.7% preferred the scan because it was "more comfortable."

Conclusions: Despite the high accuracy of chairside oral scanners, alginate impressions are still the preferred model acquisition method with respect to chair time and patient acceptance. As digital technology continues to progress, intraoral scanning may become more accepted for use in orthodontics.

MeSH terms

  • Adolescent
  • Adult
  • Alginates / chemistry
  • Bicuspid / anatomy & histology
  • Child
  • Computer-Aided Design / standards*
  • Computer-Aided Design / statistics & numerical data
  • Cuspid / anatomy & histology
  • Dental Arch / anatomy & histology
  • Dental Impression Materials / chemistry
  • Dental Impression Technique / standards*
  • Dental Impression Technique / statistics & numerical data
  • Dental Occlusion, Centric
  • Dimensional Measurement Accuracy
  • Female
  • Humans
  • Image Processing, Computer-Assisted / standards
  • Image Processing, Computer-Assisted / statistics & numerical data
  • Imaging, Three-Dimensional / standards
  • Imaging, Three-Dimensional / statistics & numerical data
  • Incisor / anatomy & histology
  • Jaw Relation Record
  • Male
  • Middle Aged
  • Models, Dental / standards*
  • Models, Dental / statistics & numerical data
  • Molar / anatomy & histology
  • Patient Satisfaction*
  • Time Factors
  • Young Adult


  • Alginates
  • Dental Impression Materials