3D-printed mandibular overdentures made with three different impression techniques

Impact of Impression Techniques on Patient Satisfaction and Chewing Efficiency in 3D-Printed Implant Overdentures: A Crossover Study

This trial will test three ways of taking impressions to see which produces the best 3D-printed lower implant overdenture for people without teeth.

Quick facts

• Phase: NA
• Study type: Interventional
• Enrollment: 16 (estimated)
• Ages: 45 Years and up
• Sex: All
• Sponsor: Mansoura University (other)
• Drugs / interventions: chemotherapy
• Locations: 1 site (Al Mansurah, Dakahlia Governorate)
• Trial ID: NCT07208812 on ClinicalTrials.gov

What this trial studies

This randomized crossover trial at the Faculty of Dentistry, Mansoura University will enroll 16 completely edentulous adults aged 45–70 who will receive two implants in the mandibular canine region. Each participant will receive three 3D-printed mandibular overdentures fabricated from impressions taken by (1) a conventional open-tray implant-level technique, (2) a functionally generated reline technique, and (3) a mucostatic base with functional borders, wearing each prosthesis for three months with a two-week washout between phases. The primary outcome is masticatory efficiency measured by a color-mixing ability test at 3, 6, and 9 months, and patient satisfaction is a secondary outcome measured by a visual analog scale at the same intervals. Randomization determines the sequence of impressions in this crossover design to control for order effects.

Who should consider this trial

Good fit: Adults aged 45–70 who are completely edentulous in the mandible, healthy enough for two mandibular implants, and with adequate mandibular bone and firm mucosa are the ideal candidates.

Not a fit: Patients with systemic diseases affecting bone healing, recent head or neck irradiation, uncontrolled metabolic bone disease, heavy smoking or alcoholism, parafunctional habits like bruxism, or insufficient mandibular bone are unlikely to benefit or qualify.

Why it matters

Potential benefit: If successful, this could identify the impression method that produces better chewing function and greater comfort for 3D-printed mandibular implant overdentures.

How similar studies have performed: Two-implant mandibular overdentures are a well-established standard and some studies support digital and 3D-printed prostheses, but direct comparisons of these specific impression techniques for 3D-printed overdentures are limited.

Eligibility criteria

Inclusion Criteria:

* Healthy patients, free from systemic diseases that affect bone resorption (e.g., uncontrolled diabetes, osteoporosis)
* Residual alveolar ridges covered with healthy, firm mucosa
* Adequate mandibular bone length and width to accommodate standard implant sizes.
* Angle's Class I maxillo-mandibular relationship.

Exclusion Criteria:

* Absolute contraindications to implant placement (e.g., active cancer, immune system diseases)
* History of head and neck irradiation or chemotherapy within the past 3 years
* Metabolic bone diseases such as uncontrolled diabetes, osteoporosis, or hyperparathyroidism
* Parafunctional habits such as bruxism or clenching
* Smoking or alcoholism
* Any physical or medical condition that may interfere with study follow-up or implant success

Where this trial is running

Al Mansurah, Dakahlia Governorate

• Faculty of Dentistry, Mansoura University — Al Mansurah, Dakahlia Governorate, Egypt (RECRUITING)

Study contacts

• Principal investigator: Shimaa E Aboelenin — Faculty of Dentistry, Mansoura University
• Study coordinator: Shimaa E Aboelenin

Conditions: Edentulism, 3D-Printed Implant Overdenture, Impression Techniques, Chewing Efficiency, Patient Satisfaction