Malocclusion, Orthodontic Relapse
Conditions
Keywords
Orthodontic retention, Fixed retainer, 3D-printed retainer, Cobalt-Chromium, Titanium, Multistranded stainless steel retainer, Randomized clinical trial, Little's Irregularity Index
Brief summary
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.
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.
Interventions
DEVICEConventional Multistranded Stainless Steel Fixed Retainer
Conventional 0.0215-inch six-stranded stainless steel bonded fixed retainer.
DEVICE3D-Printed Cobalt-Chromium Fixed Retainer
Customized 3D-printed cobalt-chromium bonded fixed retainer fabricated from intraoral scans.
DEVICE3D-Printed Titanium Fixed Retainer
Customized 3D-printed titanium (Ti-6Al-4V) bonded fixed retainer fabricated from intraoral scans.
Sponsors
Minia University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
Participants will be randomly assigned in a 1:1:1 ratio into three parallel groups to receive either a conventional multistranded stainless steel fixed retainer, a 3D-printed Cobalt-Chromium fixed retainer, or a 3D-printed Titanium Grade 5 fixed retainer.
Eligibility
Sex/Gender
ALL
Age
21 Years to 35 Years
Healthy volunteers
Yes
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Orthodontic stability assessed using Little's Irregularity Index | 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. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Retainer failure rate | 12 months | Assessment of the failure rate of conventional stainless steel, 3D-printed cobalt-chromium, and 3D-printed titanium fixed retainers. |
| Plaque Index (Silness and Löe Plaque Index) | 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 1. A film of plaque detectable by probe 2. Moderate plaque accumulation 3. Abundant plaque accumulation Lower scores indicate better oral hygiene. |
| Gingival Index (Löe and Silness Gingival Index) | 12 months | Gingival inflammation will be assessed using the Löe and Silness Gingival Index, which is scored from 0 to 3: 0: Normal gingiva 1. Mild inflammation 2. Moderate inflammation 3. Severe inflammation Lower scores indicate better gingival health. |
| Bleeding on Probing (BOP) | 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. |
| Probing Pocket Depth (PPD) | 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. |
Contacts
CONTACTSalma A Daabis, BDS
CONTACTAhmed Sh Hashem, Professor
PRINCIPAL_INVESTIGATORSalma A daabis, BDS
Minia University
PRINCIPAL_INVESTIGATORAhmed Sh Hashem, Professor
Minia University
Outcome results
None listed