A Comparison of Direct 3D Printed Clear Aligner System and Indirect Clear Aligner Systems With Fixed Orthodontic Treatment in Terms of Endocrine Disrupting Monomer Release, Treatment Effectiveness and Efficiency

September 21, 2025 updated by: Ahmet Yağcı

Comparison of Clear Aligner System Produced Directly by the Orthodontist and Indirect Clear Aligner Systems With Fixed Orthodontic Treatment in Terms of Endocrine Disrupting Monomer Release: In-vivo Randomized Controlled Clinical Study

The aim of this study is to evaluate the release of endocrine disrupting monomers from clear aligners as a result of exposure to intraoral factors by measuring their concentration in saliva and to evaluate their reliability of use in terms of general health by comparing them with the fixed orthodontic treatment group. It is also aimed to compare the groups in terms of treatment effectiveness and efficiency.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

The aim of our study is to evaluate the saliva concentration of endocrine-disrupting monomers released from attachments used and clear aligners produced directly by the orthodontist in the clinic and indirectly produced by companies. Accordingly comparing them with the fixed orthodontic treatment group and assessing clear aligner's safety for general health. It is also aimed to compare the groups in terms of treatment effectivenes and total time spent . Endocrine-disrupting chemicals are substances that interfere with the synthesis, metabolism, or effects of hormones, causing deviation from normal reproduction and homeostatic control in organisms. Bisphenol A (BPA), a monomer, is also included in the chemicals listed as endocrine disruptors by the World Health Organization. Different studies have suggested that Bisphenol A may cause adverse health effects by acting as an endocrine disruptor. While previous research has been conducted on BPA release or monomer leakage related to orthodontic materials, there is limited evidence regarding the safety aspects of thermoplastic aligners or retainers. The concentrations of endocrine-disrupting monomers in the saliva of patients undergoing treatment with directly produced aligners by orthodontists and indirectly produced aligners by companies will be examined in comparison to patients undergoing fixed orthodontic treatment. Patients will not receive any treatment other than routine orthodontic care.

Study Type

Interventional

Enrollment (Actual)

52

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 Locations

  • Turkey (Türkiye)
      • Kayseri, Turkey (Türkiye), 38000
        • Erciyes University,Faculty of Dentistry,Department of Orthodontics

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

  • Child
  • Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Absence of primary teeth in the oral cavity, with permanent teeth fully erupted,
  • Presence of a non-extraction orthodontic treatment plan,
  • Age range of 15 to 24 years,
  • Presence of mild to moderate dental crowding (0-6 mm of crowding),
  • Classification as skeletal Class I (ANB: 2±2°),
  • Absence of any craniofacial anomalies,
  • Normal vertical growth pattern (Sn-GoGn: 32±6°),
  • No congenital tooth agenesis (excluding third molars),
  • Absence of atypical tooth morphology,
  • No extracted permanent teeth,
  • Absence of dental caries,
  • Good level of oral hygiene,
  • Healthy periodontal tissues.

Exclusion Criteria:

  • Presence of any systemic disease,
  • History of previous fixed orthodontic treatment,
  • History of allergy to any dental material,
  • Use of medications containing estrogen analogs,
  • Patients with a history of xerostomia and a salivary flow rate of less than 0.1 ml per minute,
  • Patients with more than five composite restorations.

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: Fixed Orthodontic Treatment Group
In the fixed orthodontic treatment group, all tooth surfaces to which brackets would be bonded were etched with 37% phosphoric acid (dline Phosphoric Acid Etching Gel UAB, Medicinos linij Karaliauciaus str. 29 LT-78348 Siauliai Lithuania) for 30 seconds, then bond (3M Unitek Transbond XT, Minnesota, U.S.A.) was applied and light was applied to all teeth separately for 5 seconds with a light device (Valo Cordless curing light Ultradent Products, Inc. 505 W. Ultradent Drive (10200 South) South Jordan, UT 84095) [165, 166]. Afterwards, composite (3M Unitek Transbond XT, Minnesota, U.S.A.) was applied to the base of the metal brackets (AO Mini Master Roth 018, Altenhofstrasse 80, 66386 St. Ingbert, Germany) and after it was placed on the tooth surface and the composite residues around the bracket were cleaned, light was applied for 5 seconds for each bracket. Then, arch wires were applied and the fixed orthodontic treatment of the patients was started.
Device: Fixed Orthodontic Appliance Treatment
Fixed orthodontic treatment is a type of orthodontic treatment performed by applying brackets and wires to the teeth and is considered the gold standard for orthodontic treatments.
Experimental: Dİrect In-House Aligner Group
Patients in this group are treated with clear aligners produced directly by the clinician. The physical model production step is eliminated with direct production technique.Intraoral scan images were obtained from these patients with the 3Shape TRIOS (3Shape, Copenhagen, Denmark) scanning device. Then, the 3D scan images were transferred to the Maestro 3D Dental Studio (New Age, Pisa, Italy) computer software. Using these scan images, the teeth were gradually moved according to the planned final treatment result. The number of clear paligners required is calculated by the program according to the total amount of planned tooth movement. Then, Tera Harz TC-85DAC (Graphy, Seoul, Korea) resin and Asiga MAX UV (Asiga, Sydney, Australia) 3D printer were used for the direct production of the plates designed in the program. The aligners produced were then delivered to the patients.
Device: Clear aligner treatment
Clear aligners are appliances that allow the teeth to be gradually moved to the desired final position, as planned in the computer program, in a way that each aligner will perform a part of the total movement with its use.
Experimental: Invisalign Group
Intraoral scan images were obtained with the 3Shape TRIOS (3Shape, Copenhagen, Denmark) scanning device from patients who would receive Invisalign (Align Technology, Santa Clara, CA) clear aligners. These 3D intraoral scan images, together with the intraoral and extraoral photographs, radiographic records, and clinical examination findings obtained from the patients, were uploaded to the cloud software 'ClinCheck' for Invisalign . Necessary instructions were written regarding the patients' treatment plans. Afterwards, patient specific 3D treatment simulations sent to the clinician by the companies were reviewed and the necessary revisions were made. The final accepted treatment plan was approved and the aligners were produced by the relevant companies and sent to the clinic.The clear aligners produced are delivered to the patients and treatment started.
Device: Clear aligner treatment
Clear aligners are appliances that allow the teeth to be gradually moved to the desired final position, as planned in the computer program, in a way that each aligner will perform a part of the total movement with its use.
Experimental: ClearCorrect Group
Intraoral scan images were obtained with the 3Shape TRIOS (3Shape, Copenhagen, Denmark) scanning device from patients who would receive Invisalign (Align Technology, Santa Clara, CA) and ClearCorrect (ClearCorrect®, Round Rock, TX, USA) clear aligners. These 3D intraoral scan images, together with the intraoral and extraoral photographs, radiographic records, and clinical examination findings obtained from the patients, were uploaded to the cloud software 'ClinCheck' for Invisalign . Necessary instructions were written regarding the patients' treatment plans. Afterwards, patient specific 3D treatment simulations sent to the clinician by the companies were reviewed and the necessary revisions were made. The final accepted treatment plan was approved and the aligners were produced by the relevant companies and sent to the clinic.The clear aligners produced are delivered to the patients and treatment started.
Device: Clear aligner treatment
Clear aligners are appliances that allow the teeth to be gradually moved to the desired final position, as planned in the computer program, in a way that each aligner will perform a part of the total movement with its use.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Bisphenol A Concentration
Time Frame: up to 1 year
Bisphenol A concentration in patients' saliva is measured as ng/ml.
up to 1 year

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Treatment efficiency
Time Frame: up to 1 year
The total time required to complete the treatment is calculated.
up to 1 year
Treatment Effectiveness (via PAR İndex)
Time Frame: up to 1 year
The percentage decrease in the PAR score is calculated for each group.
up to 1 year

Collaborators and Investigators

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

Sponsor

Ahmet Yağcı

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

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 (Actual)

October 1, 2023

Primary Completion (Actual)

December 12, 2024

Study Completion (Actual)

February 18, 2025

Study Registration Dates

First Submitted

November 11, 2024

First Submitted That Met QC Criteria

November 11, 2024

First Posted (Actual)

November 12, 2024

Study Record Updates

Last Update Posted (Estimated)

September 25, 2025

Last Update Submitted That Met QC Criteria

September 21, 2025

Last Verified

November 1, 2024

More Information

Terms related to this study

Keywords

Other Study ID Numbers

  • TDH-2024-13280

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

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.

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