Direct Comparison Between Intraoral Scanning and Alginate Impressions for Pediatric Patients: An In Vitro Study

Purpose: To compare the accuracy and efficiency of both alginate and digital impression techniques in a method representative of a clinical setting. By evaluating the difference in fabrication time and accuracy for these techniques, it can be determined if using digital scanning is a viable alternative to alginate impressions to fabricate pediatric dental appliances.
Methods: Both the alginate and digital impressions were taken from the same pediatric typodont study model. The alginate impressions were handled and poured up, per product instructions, and digital impressions were 3D printed. A digital caliper was used to measure different landmarks on both the stone models and 3D printed models, and these measurements were compared to the pediatric typodont to determine accuracy. All steps in the process, including obtaining the impression, fabrication of the model and total time, were recorded to determine the efficiency of both methods.
Results: The alginate models had a significantly higher intercanine distance than the control. Measurements of anterior-posterior (AP) left, AP right, left central, and right central were larger than the control but did not show a significant difference in measurement. The alginate group had a significantly shorter impression time. Model fabrication time between the two groups was similar.
Conclusion: Alginate impressions require less chairside time and the digital technique was shown to be accurate in all measurements. Digital scanning may be a good alternative to alginate impressions for pediatric patients.