3D-Printed vs Conventional Fixed Retainers After Orthodontic Treatment
July 30, 2026 updated by: Salma Daabis, Minia University
Comparison Between Three-Dimensionally Printed Fixed Retainers Versus Conventional Multistranded Stainless Steel Fixed Retainers: Randomized Clinical Trial
This randomized clinical trial aims to compare the clinical performance of two types of three-dimensionally printed fixed retainers (Cobalt-Chromium and Titanium Grade 5) with the conventional multistranded stainless steel fixed retainer following orthodontic treatment.
Thirty-six participants will be randomly allocated into three parallel groups with a 1:1:1 allocation ratio.
The primary outcome is post-treatment stability assessed by Little's Irregularity Index and lower arch dimensions.
Secondary outcomes include bond failure rate and periodontal parameters over a 12-month follow-up period.
Study Overview
Status
Not yet recruiting
Conditions
Detailed Description
Orthodontic relapse remains one of the greatest challenges following the completion of orthodontic treatment. Conventional multistranded stainless steel fixed retainers are considered the gold standard for long-term retention; however, they have several limitations, including operator-dependent adaptation, prolonged chairside time, structural instability, and possible unwanted tooth movement.
Advances in digital dentistry have introduced CAD/CAM technology and additive manufacturing (3D printing), enabling the fabrication of customized fixed retainers with improved adaptation and manufacturing accuracy. Three-dimensional printed retainers fabricated from Cobalt-Chromium (Co-Cr) and Titanium Grade 5 (Ti-6Al-4V) alloys may provide superior mechanical properties, greater manufacturing precision, and potentially improved clinical performance compared with conventional retainers.
Study Type
Interventional
Enrollment (Estimated)
36
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
- Name: Salma A Daabis, BDS
- Phone Number: +201066600270
- Email: salma.daabis@pua.edu.eg
Study Contact Backup
- Name: Ahmed Sh Hashem, Professor
- Phone Number: +201002024437
- Email: ahmedshawkydent@yahoo.com
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:
- Age range 21-35 years old after finishing orthodontic treatment.
- Presence of all maxillary and mandibular anterior teeth with normal shape and size.
- Completion of orthodontic treatment with full fixed appliances.
Exclusion Criteria:
- Patients with cleft lip and/or palate or any other craniofacial syndrome
- Patients with compromised oral hygiene or periodontal disease
- Patients who had orthognathic surgery
- Lingual appliance treatments
- Enamel hypoplasia, fluorosis, active caries, restorations, or fractures in the anterior teeth
- Patients who had separate arch debondings with a difference of more than 2 months in-between jaws
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: None (Open Label)
Arms and Interventions
Participant Group / Arm |
Intervention / Treatment |
|---|---|
|
Experimental: Conventional Stainless Steel Fixed Retainer
Participants receive a conventional multistranded stainless steel fixed retainer bonded after orthodontic debonding.
|
Conventional 0.0215-inch six-stranded stainless steel bonded fixed retainer.
|
|
Experimental: 3D-Printed Cobalt-Chromium Fixed Retainer
Participants receive a customized 3D-printed cobalt-chromium fixed retainer bonded after orthodontic debonding
|
Customized 3D-printed cobalt-chromium bonded fixed retainer fabricated from intraoral scans.
|
|
Experimental: 3D-Printed Titanium Fixed Retainer
Participants receive a customized 3D-printed titanium (Ti-6Al-4V) fixed retainer bonded after orthodontic debonding.
|
Customized 3D-printed titanium (Ti-6Al-4V) bonded fixed retainer fabricated from intraoral scans.
|
What is the study measuring?
Primary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
|---|---|---|
|
Orthodontic stability assessed using Little's Irregularity Index
Time Frame: 12 months
|
Orthodontic stability will be assessed using Little's Irregularity Index on digital models.
The Little's Irregularity Index ranges from 0 mm to higher positive values.
A score of 0 mm indicates perfect alignment.
Higher scores indicate greater relapse, whereas lower scores indicate better orthodontic stability.
|
12 months
|
Secondary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
|---|---|---|
|
Retainer failure rate
Time Frame: 12 months
|
Assessment of the failure rate of conventional stainless steel, 3D-printed cobalt-chromium, and 3D-printed titanium fixed retainers.
|
12 months
|
|
Probing Pocket Depth (PPD)
Time Frame: 12 months
|
Assessment of periodontal pocket depth using a periodontal probe.
Pocket depth will be recorded in millimeters (mm).
Lower values indicate better periodontal health.
|
12 months
|
|
Plaque Index (Silness and Löe Plaque Index)
Time Frame: 12 months
|
Dental plaque accumulation will be assessed using the Silness and Löe Plaque Index, which is scored from 0 to 3: 0: No plaque
Lower scores indicate better oral hygiene. |
12 months
|
|
Gingival Index (Löe and Silness Gingival Index)
Time Frame: 12 months
|
Gingival inflammation will be assessed using the Löe and Silness Gingival Index, which is scored from 0 to 3: 0: Normal gingiva
Lower scores indicate better gingival health. |
12 months
|
|
Bleeding on Probing (BOP)
Time Frame: 12 months
|
Assessment of bleeding on probing as an indicator of gingival inflammation.
Bleeding on probing will be assessed as the percentage of bleeding sites (0-100%).
Lower percentages indicate better periodontal health.
|
12 months
|
Collaborators and Investigators
This is where you will find people and organizations involved with this study.
Sponsor
Investigators
- Principal Investigator: Salma A daabis, BDS, Minia University
- Principal Investigator: Ahmed Sh Hashem, Professor, Minia University
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)
August 1, 2026
Primary Completion (Estimated)
August 1, 2027
Study Completion (Estimated)
September 1, 2027
Study Registration Dates
First Submitted
July 7, 2026
First Submitted That Met QC Criteria
July 22, 2026
First Posted (Actual)
July 28, 2026
Study Record Updates
Last Update Posted (Actual)
July 31, 2026
Last Update Submitted That Met QC Criteria
July 30, 2026
Last Verified
July 1, 2026
More Information
Terms related to this study
Keywords
Additional Relevant MeSH Terms
Other Study ID Numbers
- SDD-RCT-2026-01
Plan for Individual participant data (IPD)
Plan to Share Individual Participant Data (IPD)?
NO
IPD Plan Description
No plan to share individual participant data (IPD).
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.