Tooth Discoloration and Chairside Handling Time (Bonding-Debonding) in Flowable Versus Packable Composites for Clear Aligner Bonded Attachments: A Randomized Clinical Trial

Comparison of Color Stability, Bonding Time, and White Spot Lesion Between Flowable Nanocomposite and Packable Microhybrid Composite Used for Clear Aligner Attachments: A Split-Mouth Randomized Clinical Trial

This randomized split-mouth clinical trial aims to compare two different composite materials used for bonding attachments in clear aligner orthodontic therapy. Twenty adult participants with Class I malocclusion and mild crowding will receive flowable nanocomposite attachments on one side of the dental arch and packable microhybrid composite attachments on the opposite side. The primary outcome is the color change (ΔE) of the enamel surface after attachment removal, measured by a spectrophotometer (VITA Easyshade). Secondary outcomes include bonding and debonding time and changes in enamel surface roughness before and after treatment. The study will be conducted at the Orthodontic Department, College of Dentistry, University of Sulaimani. The goal is to determine which composite material provides better color stability, easier handling, and minimal impact on enamel surface characteristics during clear aligner therapy.

Study Overview

• Status: Recruiting
• Conditions: Clear Aligner Orthodontic Treatment; Composite Attachment; Color Stability of Enamel
• Intervention / Treatment: Device: Packable Microhybrid Composite Resin; Device: flowable nanohybrid Composite Resin

Detailed Description

Clear aligner therapy has become a popular alternative to conventional fixed orthodontic appliances due to its superior esthetics and comfort. However, the efficiency of aligner treatment often depends on the proper use of composite attachments that enhance tooth movement and retention. Different composite resins are used for this purpose, but their optical stability and effect on enamel integrity after removal remain concerns.

This prospective, split-mouth randomized clinical trial compares a flowable nanocomposite and a packable microhybrid composite used for clear aligner attachments. Each participant will receive both materials in opposite quadrants to minimize inter-individual variability. Outcomes will include enamel color change (ΔE CIE Lab* values), bonding/debonding time, and surface roughness assessment using digital and optical analysis methods.

The study hypothesis is that the flowable nanocomposite will exhibit superior color stability and faster handling time, with comparable enamel surface effects to the packable composite. Results from this trial may help establish standardized protocols for attachment material selection in clinical orthodontic practice.

• Study Type: Interventional
• Enrollment (Estimated): 20
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Elaf Hussein Hasan H Hasan, BSD; Phone Number: +9647715671612; Email: elafhussein9494@gmail.com
• Study Contact Backup: Name: . Hadi Mohammad M Ismail, PHD; Phone Number: +9647702106211; Email: hadi.ismail@univsul.edu.iq

Study Locations

• Iraq
  • Kirkuk Governorate
    • Kirkuk, Kirkuk Governorate, Iraq
      • Recruiting
      • Private Orthodontic Clinic - Kirkuk
      • Contact: Elaf H Hasan, BSD,MSD candidate; Phone Number: +9647715671612; Email: elafhussein9494@gmail.com
  • Province
    • Kirkuk, Province, Iraq
      • Not yet recruiting
      • Private Orthodontic Clinic - Kirkuk
      • Contact: Elaf H Hasan, BSD,MSD candidate; Phone Number: +9647715671612; Email: elafhussein9494@gmail.com
      • Contact: Hadi M Ismail, PHD; Phone Number: +9647702106211; Email: hadi.ismail@univsul.edu.iq

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Adults 18-40 years.
• patients with class l malocclusion with in which there treatment will be completed in 6 month .
• Completed clear aligner therapy and scheduled for attachment debonding at the study clinic.
• Permanent teeth with intact buccal enamel at assessment sites.
• No caries, restorations, cracks, fluorosis, or hypoplasia on assessed surfaces.
• No bleaching within 6 months prior to baseline.
• Good general health (ASA I-II) and able to provide written informed consent.
• Satisfactory oral hygiene and gingival health (e.g., GI ≤ 1).
• Willing and able to complete measurements: spectrophotometric shade (CIE L*, a*, b*), photographs/scans, and VAS for pain/discomfort.
• Available for all visits and follow-up assessment.

Exclusion Criteria:

• Patients younger than 18 or older than 40 years.
• Patients presenting with severe or very severe anterior crowding (LII > 6 mm) or spacing will exclude from the study. Cases with posterior crossbites, open bites, or skeletal discrepancies
• Presence of systemic diseases (ASA > II) that may affect healing, pain perception, or enamel quality.
• Teeth with caries, restorations, fractures, enamel cracks, fluorosis, hypoplasia, or discolorations on the buccal surfaces at assessment sites.
• Patients who have undergone tooth bleaching within the last 6 months.
• History of major dental surgery or trauma in the study region.
• Patients with poor oral hygiene or gingival inflammation (GI > 1).
• Pregnant or lactating women.
• Patients with allergy or hypersensitivity to composite resins or dental adhesives.
• Individuals unable to provide informed consent or not willing to comply with study visits.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: packable microcomposite (Group A); Participants will receive packable microcomposite attachments (e.g., GC G-ænial Universal ) on one side of the dental arc attachments on one quadrant of the dental arch for clear aligner therapy. Color change, bonding/debonding time, and enamel roughness will be assessed	Device: Packable Microhybrid Composite Resin; Packable microhybrid composite resin used to fabricate clear aligner attachments.
Active Comparator: flowable nanohybrid Composite (Group B); Participants will receive flowable nanocomposite (e.g., GC aligner connect ) attachments on the opposite quadrant of the same dental arch.Color change, bonding/debonding time, and enamel roughness will be assessed.	Device: flowable nanohybrid Composite Resin; A flowable nanocomposite (e.g., GC aligne connect) used to fabricate clear aligner attachments on enamel surfaces for comparison; Other Names: packable microhybrid composite

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Tooth Color (ΔE) After Attachment Removal	The color change (ΔE) of the enamel surface will be measured using a VITA Easyshade spectrophotometer based on CIE Lab* values before bonding and after debonding of the attachments. A ΔE value ≥ 3.3 will be considered clinically perceptible.	Baseline (before bonding) and after attachment removal

Collaborators and Investigators

• Sponsor: University of Sulaimani
• Investigators: Principal Investigator: Ali I Ibrahim, College of Dentistry, University of Sulaimani.

Publications and helpful links

General Publications

• Lin S, Huang L, Li J, Wen J, Mei L, Xu H, Zhang L, Li H. Assessment of preparation time and 1-year Invisalign aligner attachment survival using flowable and packable composites. Angle Orthod. 2021 Sep 1;91(5):583-589. doi: 10.2319/063020-598.1.

Study record dates

Study Major Dates

• Study Start (Actual): October 15, 2025
• Primary Completion (Estimated): July 15, 2026
• Study Completion (Estimated): December 16, 2026

Study Registration Dates

• First Submitted: November 14, 2025
• First Submitted That Met QC Criteria: November 14, 2025
• First Posted (Actual): November 18, 2025

Study Record Updates

• Last Update Posted (Actual): November 18, 2025
• Last Update Submitted That Met QC Criteria: November 14, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: Composite Attachment Flowable Nanocomposite Packable Microhybrid Composite
• Other Study ID Numbers: USulaimani-Ortho-Aligner-2025; MSc-Ortho-Aligner-Study-2025; (Other Identifier: College of Dentistry, University of Sulaimani; Research Ethics Committee, College of Dentistry, University of Sulaimani)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: ot applicable. Individual participant data will not be shared. Only summarized results will be published.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No