Analysis of Orthodontic Tooth Movement Using 3D Imaging

Not Applicable

Completed

Conditions: Tooth Crowding
Malocclusion
Dental Crowding

Interventions: Device: .014"
Device: .016"
Device: Twin brackets
Device: Self-ligating brackets

Registration Number: NCT03398798

Lead Sponsor: University of North Carolina, Chapel Hill

Brief Summary: 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.

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.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 36

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 & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
.014" with twin brackets	Twin brackets	.014" dimension CuNiTi orthodontic arch wires and .022" slot Ormco Insignia Metal Twin brackets.
.014" with twin brackets	.014"	.014" dimension CuNiTi orthodontic arch wires and .022" slot Ormco Insignia Metal Twin brackets.
.016" with twin brackets	.016"	.016" dimension CuNiTi orthodontic arch wires and .022" slot Ormco Insignia Metal Twin brackets.
.016" with self-ligating brackets	Self-ligating brackets	.016" dimension CuNiTi orthodontic arch wires and .022" slot Ormco Insignia SL (self-ligating) brackets.
.014" with self-ligating brackets	.014"	.014" dimension CuNiTi orthodontic arch wires and .022" slot Ormco Insignia SL (self-ligating) brackets.
.016" with self-ligating brackets	.016"	.016" dimension CuNiTi orthodontic arch wires and .022" slot Ormco Insignia SL (self-ligating) brackets.
.016" with twin brackets	Twin brackets	.016" dimension CuNiTi orthodontic arch wires and .022" slot Ormco Insignia Metal Twin brackets.
.014" with self-ligating brackets	Self-ligating brackets	.014" dimension CuNiTi orthodontic arch wires and .022" slot Ormco Insignia SL (self-ligating) brackets.

Primary Outcome Measures

Name	Time	Method
Change in Little's Index From Baseline to 6 Weeks	Baseline and 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).
Change in Little's Index From 6 Weeks to 12 Weeks	6 weeks and 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).

Secondary Outcome Measures

Name	Time	Method
Linear Change in Tooth Position From Baseline to 6 Weeks (Translation)	Baseline and 6 weeks	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.
Linear Change in Tooth Position From 6 Weeks to 12 Weeks (Translation)	6 weeks and 12 weeks	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.
Angular Change in Tooth Position From Baseline to 6 Weeks (Rotation)	Baseline and 6 weeks	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.
Angular Change in Tooth Position From 6 Weeks to 12 Weeks (Rotation)	6 weeks and 12 weeks	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.
Correlation Between Degrees of Malalignment and Rate of Tooth Movement	Baseline and 12 weeks	A repeated measure linear regression model conducted to evaluate any correlation between the degrees of malalignment and the rate of tooth movement.

Trial Locations

Locations (2): UNC-CH School of Dentistry
🇺🇸
Chapel Hill, North Carolina, United States
Selden Orthodontics
🇺🇸
Huntersville, North Carolina, United States