Comparison of Open-Mouth and Closed-Mouth Impression Techniques for Complete Dentures

September 19, 2026 updated by: Dr. Fatima Shakeel, Watim Medical & Dental College

Comparison of Open Mouth Vs Closed Mouth Edentulous Impression Technique: A Hospital Based Study

This randomized controlled trial compares two final impression techniques for complete dentures, the open mouth technique and the closed mouth technique. Completely edentulous adults with well-formed ridges will be randomly assigned 1:1 to one of the two techniques. All dentures will be made by a single operator using the same materials and laboratory. Six weeks after insertion, an examiner blinded to group allocation will assess denture retention using the Kapur index, and patient satisfaction will be recorded using a 5-item Likert questionnaire.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Detailed Description

In the open mouth group, border molding and the wash impression are made with the patient's mouth open and no occlusal contact. In the closed mouth group, occlusal rims are attached to the custom trays at a predetermined occlusal vertical dimension, and the impression is made while the patient closes and performs functional movements. Jaw relations, try-in, and insertion follow the same protocol for both groups. Retention is scored separately for the maxillary and mandibular dentures, with a score of 2 or 3 counted as adequate. Satisfaction scores range from 5 to 25, and a score of 16 or above counts as satisfied.

Study Type

Interventional

Enrollment (Estimated)

88

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 Contact

Study Locations

    • Punjab Province
      • Rawalpindi, Punjab Province, Pakistan, 46000
        • Department of Prosthodontics, Watim Medical and Dental College, Rawat, Rawalpindi, Punjab, Pakistan
        • Contact:

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

18 years to 70 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Adults aged 18 to 70 years
  • Completely edentulous in both maxilla and mandible for at least six months, confirmed by clinical examination and orthopantomogram
  • Well-formed ridges, ACP classification Class I or Class II

Exclusion Criteria:

  • Flabby or hypermobile ridges
  • Atrophic ridges
  • Ridges with bony exostosis
  • Active oral pathology
  • History of radiotherapy to head and neck
  • Uncontrolled systemic disease
  • Neuromuscular or neurological disorders

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: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Group A: Open Mouth Technique

Final impressions made in custom trays with sectional border molding using low fusing impression compound and a zinc oxide eugenol wash, with the mouth open and no occlusal contact.

Secondary impression of the edentulous arch made in a custom acrylic tray. Border molding is done in sections with low fusing impression compound, followed by a zinc oxide eugenol wash impression. The clinician manipulates the tissues and the patient performs functional movements, with the mouth open and no occlusal contact. All steps are done by a single trained operator using the same materials and laboratory as the comparison group.

Other Names:
  • Open mouth functional impression
  • Conventional border molded impression
Active Comparator: Group B: Closed Mouth Technique

Final impressions made in custom trays with attached occlusal rims set to a predetermined vertical dimension. Border molding and the wash impression are made while the patient closes into occlusion and performs functional movements.

Secondary impression made in custom trays with occlusal rims attached and adjusted to a predetermined occlusal vertical dimension. Maxillary and mandibular trays are inserted together. Border molding with low fusing impression compound and a zinc oxide eugenol wash impression are made while the patient closes into occlusion and performs functional movements, recording the denture bearing areas under simulated functional load. All steps are done by a single trained operator using the same materials and laboratory as the comparison group.

Other Names:
  • Closed mouth functional impression
  • Functional impression under occlusal loading

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Adequate retention of maxillary denture
Time Frame: 6 weeks after denture insertion

Kapur index score (0 nil, 1 poor, 2 fair, 3 good) assessed by a blinded examiner. A score of 2 or 3 is adequate and 0 or 1 is inadequate.

6 weeks after denture insertion

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Adequate retention of mandibular denture
Time Frame: 6 weeks after denture insertion

Kapur index score assessed the same way as the maxillary denture.

6 weeks after denture insertion
Patient satisfaction
Time Frame: 6 weeks after denture insertion

5-item Likert questionnaire covering retention, comfort, mastication, phonetics, and overall satisfaction, with a total score of 5 to 25. A score of 16 or above counts as satisfied.

6 weeks after denture insertion

Collaborators and Investigators

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

Sponsor

Investigators

  • Principal Investigator: Fatima Shakeel, BDS, Watim Medical and Dental College
  • Study Director: Zarah Afreen, BDS, FCPS, Watim Medical and Dental College

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 (Estimated)

March 1, 2027

Primary Completion (Estimated)

June 1, 2027

Study Completion (Estimated)

June 1, 2027

Study Registration Dates

First Submitted

September 15, 2026

First Submitted That Met QC Criteria

September 15, 2026

First Posted (Actual)

September 21, 2026

Study Record Updates

Last Update Posted (Actual)

September 23, 2026

Last Update Submitted That Met QC Criteria

September 19, 2026

Last Verified

September 1, 2026

More Information

Terms related to this study

Other Study ID Numbers

  • WMDC/R&D(ERB)/2025/241

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Individual participant data will not be shared publicly to protect participant confidentiality. Summary results will be published in a peer-reviewed journal.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

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.