Skip to main content
OpenTrials
Enrolling by Invitation

NCT Number: NCT07350343

The Predictability of Directly Printed Versus Thermoformed Clear Aligners

The study is randomized controlled trial ...The null hypothesis suggests that there is no significant difference between actual and predicted dental movement in patients treated using direct printed aligners produced with Graphy™ Tera Harz TA-28 resin as compared to those treated with thermoformed clear aligners.

Enrolling by Invitation

Interested in participating?

Request Info

Key information

Conditions

Class I Malocclusion Behavior Crowded Teeth Crowding Malocclusion Malocclusion, Angle Class I Rotation Spacing of Anterior Teeth Spatial Behavior Stomatognathic Diseases Tooth Diseases

Age range

16 year–40 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

The sample will be recruited from multicentre clinics (Private dental clinic, Orthodontic Department at Karbala Governmental Specialized Dental Centre, Orthodontic Department, College of Dentistry University of Baghdad).

Karbala, Iraq

About this study

the patients will be randomly assigned to one of two study groups which either direct printed or thermoformed clear aligner. All patients would be given the same instructions: aligners had to be worn for at least 22 hours per day, except during meals and oral hygiene activities, and should be changed every 10 days.Teeth positions would be planned according to esthetic and functional principles, starting with the 3D T0 digital model and aligning and leveling dental arches following orthodontic aligner biomechanical principles. Each aligner had a planned movement speed of 0.2 mm linear displacement, 2° long-axis rotation, and a vestibulo-lingual inclination of 2.5°.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Patients with mild to moderate malocclusion that can be treated by less than 40 steps of aligner treatment, including those with dental rotation of < 30°, diastema or crowding of < 8 mm.
  • Patients aged ≥ 16 years with fully erupted permanent teeth (regardless of the third molar).
  • No supernumerary teeth, no enamel malformation.
  • No tooth shape anomalies

Exclusion criteria

  • Systemic pathologies such as uncontrolled diabetes or heart diseases
  • active or past periodontal disease
  • previous orthodontic treatment
  • temporomandibular joint disorders
  • ongoing pharmacological treatment could influence orthodontic treatment.

Treatment and study plan

Direct-printed aligner (Graphy)

Device

intraoral scanner would be used to scan patient teeth then aligner fabrication by direct printing then the patient will be treated with direct-printed aligners(graphy) until dental levelling alignment; space closure is finished. All patients would be given the same instructions: aligners had to be worn for at least 22 hours per day, except during meals and oral hygiene activities, and should be changed every 10 days.

Thermoformed aligner

Device

An intraoral scanner would be used to scan patient teeth then aligner fabrication by thermoforming then the Patients will be treated with thermoformed aligners until dental alignment, levelling, space closure is finished. All patients would be given the same instructions: aligners had to be worn for at least 22 hours per day, except during meals and oral hygiene activities, and should be changed every 10 days.

Primary outcomes

  1. predictability of tooth movement

    Time frame: 12 months

    The primary outcome will be calculated as the percentage difference between the final and initial positions for each individual tooth movement assessed and will be expressed as a continuous numerical variable representing tooth movement predictability (%).

Secondary outcomes

  1. predictability within different types

    Time frame: 12 months

    • The secondary outcome will be assessed by comparing the predictability within different types of tooth movement of the same group.

  2. Colour change of clear aligners

    Time frame: 12 months

    UV-Visible spectrophotometer for samples from both groups before and after intraoral aging.

  3. Degree of Conversion

    Time frame: 12 months

    Assessment of the Degree of Conversion of direct printed Tera Harz TA-28 resin using Fourier-transform infrared (FTIR) spectroscopy for the liquid resin before curing and for samples after curing and post-processing.

  4. shape memory effect

    Time frame: 12 months

    Assessment of the shape memory effect of direct printed Tera Harz TA-28 aligners, the bending test would be used to investigate and directly visualize the shape recovery property.

Sponsors and collaborators

Lead sponsor

University of Baghdad

Other

Registry information

Official study title

The Predictability of Directly Printed Shape Memory (Graphy) Versus Thermoformed Clear Aligners: A Randomized Clinical Trial

Important dates

Study start
2026
Primary completion
2027
Study completion
2027
First posted
Jan 20, 2026
Registry last updated
Apr 15, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.