Related Experiment Video
Updated: Oct 4, 2025

A Two-interval Forced-choice Task for Multisensory Comparisons
Published on: November 9, 2018
An Updated Comparison of Current Impression Techniques Regarding Time, Comfort, Anxiety, and Preference: A Randomized
Hakan Yilmaz1, Fatma Asli Konca2, Merve Nur Aydin3
1Department of Orthodontics, Yeditepe University Faculty of Dentistry, İstanbul, Turkey.
Objective:
To compare digital and conventional impressions in terms of impression time, and comfort, anxiety and preference of the patients.
Methods:
Digital scans (Trios 3 Cart) and conventional impressions (irreversible hydrocolloid material, hand-mixed) were randomly performed on 39 patients by a single experienced operator in 14-21 day intervals (cross-over design). Impression time, comfort score with visual analog scale (VAS), anxiety level with State-Trait Anxiety Scale, and preference with a questionnaire were recorded. Two techniques were compared with the independent t-test in terms of time, comfort, and anxiety. Patient'-operator' assessment and time-comfort relationship were calculated using Pearson correlation test.
Results:
No statistical difference was found between the two impression techniques in terms of time (P = .231). The digital technique was found to be more comfortable than the conventional technique in both operators' and patients' comfort scores (P < .001). There was no statistical difference between two techniques with regards to anxiety (P = .668). Patients' and operators' comfort scores showed a strong correlation (P < .001), but no correlation was found between comfort and time (P > .05).
Conclusion:
Digital scan and conventional impression were similar in terms of impression time, and anxiety of patients. Conversely, patients were more satisfied with the digital technique and preferred it.
More Related Videos
Related Concept Videos
Bioequivalence Experimental Study Designs: Repeated Measures, Cross-Over, Carry-Over, and Latin Square Designs
Crossover Experiments
Crossover designs are performed even with smaller sample sizes since the samples can act as their controls. These are better than simple randomized trials since patients are exposed to all the treatments.
Group Design
Blind Procedures

