Intraoral Scanning Versus Alginate Impressions in Dental Students

July 10, 2026 updated by: Le Van Nhat Thang, Hue University of Medicine and Pharmacy

Procedure Time and Patient Comfort of Intraoral Scanning Versus Alginate Impressions Among Dental Students: A Randomized Clinical Trial

Dental impressions are used to create a record of a person's teeth and oral structures. Conventional impressions are made using impression material placed in a tray, whereas digital impressions are obtained using an intraoral scanner.

This randomized clinical trial compared conventional alginate impressions with digital intraoral scanning using the TRIOS 3 and Medit i700 scanners among dental students aged 18 to 24 years. Participants were randomly assigned to one of the three impression techniques. Each participant underwent recording of both the upper and lower dental arches using the assigned technique.

The study primarily compared the chairside time required for each technique and the participants' experience immediately after the procedure. Comfort, nausea, breathing, pain, dry-mouth sensation, perceived procedure speed, overall satisfaction, and preference for conventional or digital impressions were also evaluated.

Study Overview

Study Type

Interventional

Enrollment (Actual)

171

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

      • Huế, Vietnam, 530000
        • Faculty of Odonto-Stomatology, University of Medicine and Pharmacy, Hue University

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Undergraduate dental students at the University of Medicine and Pharmacy, Hue University.
  • Aged 18 to 24 years.
  • Willing to undergo one maxillary and one mandibular dental impression using the assigned technique.
  • Willing and able to complete the study questionnaire.
  • Provided written informed consent.

Exclusion Criteria:

  • Currently undergoing orthodontic treatment.
  • Presence of a systemic disease or acute condition that limited the ability to cooperate or increased the risk of discomfort during impression taking or intraoral scanning, including an acute respiratory disorder or frequent vomiting.
  • Limited mouth opening or an oral and maxillofacial condition that prevented correct impression-tray seating or scanner-tip placement according to the study protocol.
  • A maxillofacial abnormality that markedly affected the procedure or caused significant recording distortion.
  • An excessive gag reflex that prevented completion of the assigned procedure.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Diagnostic
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Conventional Alginate Impression
Participants underwent maxillary and mandibular conventional impressions using alginate impression material and stock trays according to the manufacturer's instructions.
Maxillary and mandibular conventional impressions were obtained using Tropical alginate impression material and stock trays. The alginate was mixed, placed in the impression tray, and used according to the manufacturer's instructions.
Experimental: TRIOS 3 Intraoral Scanning
Participants underwent full-arch maxillary and mandibular digital impressions and bite registration using the TRIOS 3 intraoral scanner according to the manufacturer's recommended scanning protocol.
Maxillary and mandibular full-arch digital impressions were obtained using the TRIOS 3 intraoral scanner according to the manufacturer's recommended scanning protocol. A bite-registration scan was also obtained.
Experimental: Medit i700 Intraoral Scanning
Participants underwent full-arch maxillary and mandibular digital impressions and bite registration using the Medit i700 intraoral scanner according to the manufacturer's recommended scanning protocol.
Maxillary and mandibular full-arch digital impressions were obtained using the Medit i700 intraoral scanner according to the manufacturer's recommended scanning protocol. A bite-registration scan was also obtained.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Total Chairside Procedure Time
Time Frame: During the assigned impression procedure at the single study visit
Total chairside procedure time was measured in seconds using a digital stopwatch and calculated as the sum of the recorded procedural stages. For the conventional alginate group, the stages included maxillary mixing, maxillary impression taking, mandibular mixing, and mandibular impression taking. For the digital groups, the stages included patient and case information entry, maxillary scanning, and mandibular scanning. Bite-registration time was excluded from the total procedure time because there was no equivalent stage in the conventional alginate workflow.
During the assigned impression procedure at the single study visit
Patient-Reported Overall Comfort During the Impression Procedure
Time Frame: Immediately after completion of the assigned impression procedure
Overall comfort during the assigned impression procedure was assessed immediately after the procedure using a 0-to-100 visual analogue scale. Higher scores indicated greater comfort.
Immediately after completion of the assigned impression procedure

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Van Nhat Thang Le, DDS PhD, Faculty of Odonto-Stomatology, University of Medicine and Pharmacy, Hue University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

May 1, 2025

Primary Completion (Actual)

August 31, 2025

Study Completion (Actual)

August 31, 2025

Study Registration Dates

First Submitted

July 10, 2026

First Submitted That Met QC Criteria

July 10, 2026

First Posted (Actual)

July 15, 2026

Study Record Updates

Last Update Posted (Actual)

July 15, 2026

Last Update Submitted That Met QC Criteria

July 10, 2026

Last Verified

July 1, 2026

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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