Analysis of Orthodontic Tooth Movement Using 3D Imaging

Purpose: This project aims to study the effects of wire dimension and ligation method (bracket type) on the first stage of orthodontic treatment using 3D imaging.

Participants: Up to 80 patients at UNC School of Dentistry or Selden Orthodontics between the ages of 10 and 45, inclusive, who have been previously diagnosed with malocclusion requiring orthodontic treatment (braces) and are otherwise healthy.

Procedures (methods): Subjects receiving standard of care (SOC) orthodontic treatment will be randomized to one of two commonly used orthodontic archwires (.014" or .016" diameter). Subjects will be further subdivided for analysis based on the type of bracket (twin or self-ligating) that their clinician uses in their treatment. We will review the 3D digital images of each subject's dentition recorded as part of SOC at the 0-, 6- and 12-week visits. We will retrieve the archwires when they are removed per SOC by the clinician at the 12-week time point.

Study Overview

• Status: Completed
• Conditions: Malocclusion; Tooth Crowding; Dental Crowding
• Intervention / Treatment: Device: .014"; Device: Twin brackets; Device: .016"; Device: Self-ligating brackets

Detailed Description

Many archwire dimensions and two main bracket types (twin and self-ligating) are available to orthodontists for the first stage of orthodontic treatment, but little objective clinical evidence is available to indicate which archwire dimension and bracket type is ideal for a given patient with an individual type and degree of malalignment during this stage. A limited clinical trial will be conducted to collect and analyze this data.

The aim of this study is to study the effect of wire dimension, timing and ligation method on leveling and aligning in orthodontic treatment using 3D imaging.

The study's specific aims are as follows:

1. To analyze the effect of wire dimension (.014" vs. .016") and time-course (first six weeks or second six weeks) on Stage I treatment

2. To correlate clinical tooth movements with bench data for four types of malalignment

   1. In-out
   2. Rotation
   3. Tip
   4. Vertical step
3. To analyze the effect of ligation method (twin vs. self-ligating) on Stage I treatment

These specific aims will serve to address the following hypothesis: Archwire dimension affects tooth movement in Stage I of orthodontic treatment, depending upon variation time-course (due to force decay of superelastic wires) and method of ligation (bracket type). This will be tested in a total of 80 patients who are undergoing active treatment in the University of North Carolina (UNC) orthodontic graduate clinic or at Selden Orthodontics. There will be four different groups in this study. In the twin bracket cohort, half the patients will be treated with .014" dimension wire and half will be treated with .016" dimension wire. In the self-ligating bracket cohort, half the patients will be treated with .014" dimension wire, and half will be treated with .016" dimension wire.

If the hypotheses are shown to be correct, then the subset of society receiving orthodontic treatment will be able to benefit from selection of bracket types and archwire dimensions that match their individual types and degrees of malalignment. This will allow for more efficient tooth movement with less unwanted movement, and could lead to shorter treatment times and less discomfort.

• Study Type: Interventional
• Enrollment (Actual): 36
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • North Carolina
    • Chapel Hill, North Carolina, United States, 27599
      • UNC-CH School of Dentistry
    • Huntersville, North Carolina, United States, 28078
      • Selden Orthodontics

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 10 years to 45 years (ADULT, CHILD)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• In the initial stage of active treatment at the University of North Carolina graduate orthodontic clinic or Selden Orthodontics
• Non-extraction treatment
• Maxillary and mandibular Little Index between 1-15 mm (this is a measurement of crowding)
• Presence of all permanent anterior teeth
• Age 10-45 years
• Consent to participate in the study

Exclusion Criteria:

• Systemic diseases such as diabetes, hypertension, temporomandibular disorders (TMD), craniofacial syndrome, etc.
• Any spacing between anterior teeth
• Subjects who have incisor mandibular plane angle (IMPA) greater than or equal to 100 degrees
• Anterior tooth completely blocked from the arch form
• Periodontal pocketing of any teeth greater than 4 mm
• Maxillary and mandibular Little Index >15 mm (This is a measurement of crowding. A Little Index of >15 mm indicates a need for a smaller dimension arch wire)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: TREATMENT
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: TRIPLE

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
ACTIVE_COMPARATOR: .014" with twin brackets; .014" dimension CuNiTi orthodontic arch wires and .022" slot Ormco Insignia Metal Twin brackets.	Device: .014"; .014" CuNiTi orthodontic arch wire; Device: Twin brackets; Ormco Insignia Metal Twin brackets
ACTIVE_COMPARATOR: .016" with twin brackets; .016" dimension CuNiTi orthodontic arch wires and .022" slot Ormco Insignia Metal Twin brackets.	Device: Twin brackets; Ormco Insignia Metal Twin brackets; Device: .016"; .016" CuNiTi orthodontic arch wire
ACTIVE_COMPARATOR: .014" with self-ligating brackets; .014" dimension CuNiTi orthodontic arch wires and .022" slot Ormco Insignia SL (self-ligating) brackets.	Device: .014"; .014" CuNiTi orthodontic arch wire; Device: Self-ligating brackets; Ormco Insignia SL brackets
ACTIVE_COMPARATOR: .016" with self-ligating brackets; .016" dimension CuNiTi orthodontic arch wires and .022" slot Ormco Insignia SL (self-ligating) brackets.	Device: .016"; .016" CuNiTi orthodontic arch wire; Device: Self-ligating brackets; Ormco Insignia SL brackets

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Little's Index From Baseline to 6 Weeks	Little's Index measures the distance between contact points on adjacent teeth. Little's Index will be measured at two time points (0 weeks and 6 weeks).	Baseline and 6 weeks
Change in Little's Index From 6 Weeks to 12 Weeks	Little's Index measures the distance between contact points on adjacent teeth. Little's Index will be measured at two time points (6 weeks and 12 weeks).	6 weeks and 12 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Linear Change in Tooth Position From Baseline to 6 Weeks (Translation)	Clinical linear measurements (mm) in x-, y-, and z-translation will be measured at two time points (0 weeks and 6 weeks) to determine the linear (translational) change in tooth position during that time.	Baseline and 6 weeks
Linear Change in Tooth Position From 6 Weeks to 12 Weeks (Translation)	Clinical linear measurements (mm) in x-, y-, and z-translation will be measured at two time points (6 weeks and 12 weeks) to determine the linear (translational) change in tooth position during that time.	6 weeks and 12 weeks
Angular Change in Tooth Position From Baseline to 6 Weeks (Rotation)	Clinical angular measurements (degree) in x-, y-, and z-rotation will be measured at two time points (0 weeks and 6 weeks) to determine the angular (rotational) change in tooth position during that time.	Baseline and 6 weeks
Angular Change in Tooth Position From 6 Weeks to 12 Weeks (Rotation)	Clinical angular measurements (degree) in x-, y-, and z-rotation will be measured at two time points (6 weeks and 12 weeks) to determine the angular (rotational) change in tooth position during that time.	6 weeks and 12 weeks
Correlation Between Degrees of Malalignment and Rate of Tooth Movement	A repeated measure linear regression model conducted to evaluate any correlation between the degrees of malalignment and the rate of tooth movement.	Baseline and 12 weeks

Collaborators and Investigators

• Sponsor: University of North Carolina, Chapel Hill

Study record dates

Study Major Dates

• Study Start (ACTUAL): January 15, 2018
• Primary Completion (ACTUAL): November 29, 2018
• Study Completion (ACTUAL): November 29, 2018

Study Registration Dates

• First Submitted: December 15, 2017
• First Submitted That Met QC Criteria: January 6, 2018
• First Posted (ACTUAL): January 12, 2018

Study Record Updates

• Last Update Posted (ACTUAL): May 1, 2020
• Last Update Submitted That Met QC Criteria: April 30, 2020
• Last Verified: April 1, 2020

More Information

Terms related to this study

• Keywords: archwire dimension; ligation method; bracket type
• Additional Relevant MeSH Terms: Stomatognathic Diseases; Tooth Diseases; Malocclusion
• Other Study ID Numbers: 17-1446

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: Yes