An interventional study of .014" and .016" in Tooth Crowding, Dental Crowding and Malocclusion, sponsored by University of North Carolina, Chapel Hill. Completed at 2 sites in United States. Open to participants aged 10 Years to 45 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2020-05-01.
Sponsored by University of North Carolina, Chapel Hill · Not applicable, Interventional, and Treatment
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.
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:
To correlate clinical tooth movements with bench data for four types of malalignment
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.
323 studies on the registry are indexed under Malocclusion; 85 are open to participants now.
This study's enrollment of 36 is close to the median of 37 across 242 interventional studies indexed under Malocclusion.
Browse Malocclusion studies →University of North Carolina, Chapel Hill is the lead sponsor of 1,372 studies on the registry; 133 are open to participants now.
Of its 161 completed or terminated interventional studies of FDA-regulated products, 139 (86%) have results posted.
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Exclusion Criteria:
.014" dimension CuNiTi orthodontic arch wires and .022" slot Ormco Insignia Metal Twin brackets.
Device: .014" · Device: Twin brackets
.016" dimension CuNiTi orthodontic arch wires and .022" slot Ormco Insignia Metal Twin brackets.
Device: .016" · Device: Twin brackets
.014" dimension CuNiTi orthodontic arch wires and .022" slot Ormco Insignia SL (self-ligating) brackets.
Device: .014" · Device: Self-ligating brackets
.016" dimension CuNiTi orthodontic arch wires and .022" slot Ormco Insignia SL (self-ligating) brackets.
Device: .016" · Device: Self-ligating brackets
.014" CuNiTi orthodontic arch wire
.016" CuNiTi orthodontic arch wire
Ormco Insignia Metal Twin brackets
Ormco Insignia SL brackets
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).
Time frame: 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).
Time frame: 6 weeks and 12 weeks
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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: Baseline and 12 weeks
| Milestone | .014" With Twin Brackets | .016" With Twin Brackets | .014" With Self-ligating Brackets | .016" With Self-ligating Brackets |
|---|---|---|---|---|
| Started | 9 | 9 | 9 | 9 |
| Completed | 9 | 9 | 9 | 9 |
| Not completed | 0 | 0 | 0 | 0 |
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).
| mm | .014" With Twin Brackets | .016" With Twin Brackets | .014" With Self-ligating Brackets | .016" With Self-ligating Brackets |
|---|---|---|---|---|
| Change in Little's Index From Baseline to 6 Weeks | -2.5 ± 2.2 | -2.9 ± 1.8 | -2.3 ± 1.8 | -2.6 ± 2.4 |
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).
| mm | .014" With Twin Brackets | .016" With Twin Brackets | .014" With Self-ligating Brackets | .016" With Self-ligating Brackets |
|---|---|---|---|---|
| Change in Little's Index From 6 Weeks to 12 Weeks | -0.8 ± 1.0 | -0.9 ± 0.8 | -0.2 ± 0.7 | -0.4 ± 0.8 |
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.
| mm | .014" With Twin Brackets | .016" With Twin Brackets | .014" With Self-ligating Brackets | .016" With Self-ligating Brackets |
|---|---|---|---|---|
| Translation along the x-axis | .03 ± .15 | -.05 ± .18 | -.14 ± .28 | -.09 ± .23 |
| Translation along the y-axis | .05 ± .09 | .03 ± .21 | -.08 ± .12 | .06 ± .34 |
| Translation along the z-axis | -.23 ± .34 | -.18 ± .28 | -.22 ± .3 | -.28 ± .47 |
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.
| mm | .014" With Twin Brackets | .016" With Twin Brackets | .014" With Self-ligating Brackets | .016" With Self-ligating Brackets |
|---|---|---|---|---|
| Translation along the x-axis | .05 ± .08 | .05 ± .20 | .01 ± .11 | .03 ± .17 |
| Translation along the y-axis | .03 ± .24 | .03 ± .13 | -.01 ± .09 | .03 ± .18 |
| Translation along the z-axis | -.16 ± .32 | .00 ± .22 | -.07 ± .23 | .00 ± .15 |
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.
| degrees | .014" With Twin Brackets | .016" With Twin Brackets | .014" With Self-ligating Brackets | .016" With Self-ligating Brackets |
|---|---|---|---|---|
| Rotation around the x-axis | 1.95 ± 3.09 | 1.52 ± 2.84 | 1.97 ± 2.47 | 1.91 ± 3.17 |
| Rotation around the y-axis | 1.37 ± 1.71 | .99 ± 1.26 | 1.33 ± 1.99 | 1.78 ± 2.50 |
| Rotation around the z-axis | .66 ± 1.54 | .79 ± 1.10 | .95 ± 1.45 | 1.59 ± 3.21 |
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.
| degrees | .014" With Twin Brackets | .016" With Twin Brackets | .014" With Self-ligating Brackets | .016" With Self-ligating Brackets |
|---|---|---|---|---|
| Rotation around the x-axis | .82 ± 2.00 | 1.07 ± 1.81 | .66 ± 1.50 | .40 ± 1.59 |
| Rotation around the y-axis | .86 ± 2.13 | .39 ± 1.34 | .40 ± 1.08 | -.10 ± 1.33 |
| Rotation around the z-axis | .16 ± 1.33 | .18 ± .83 | -.13 ± 1.21 | -.68 ± 2.21 |
A repeated measure linear regression model conducted to evaluate any correlation between the degrees of malalignment and the rate of tooth movement.
No measurements were reported for this outcome.
Collected over Adverse event data was collected throughout the study, a total 12 weeks.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| .014" With Twin Brackets | 0/9 (0%) | 0/9 (0%) | 0/9 (0%) |
| .016" With Twin Brackets | 0/9 (0%) | 0/9 (0%) | 0/9 (0%) |
| .014" With Self-ligating Brackets | 0/9 (0%) | 0/9 (0%) | 0/9 (0%) |
| .016" With Self-ligating Brackets | 0/9 (0%) | 0/9 (0%) | 0/9 (0%) |
| Age, Continuous(years) | .014" With Twin Brackets | .016" With Twin Brackets | .014" With Self-ligating Brackets | .016" With Self-ligating Brackets | Total |
|---|---|---|---|---|---|
| Mean | 17.2 ± 3.4 | 14.4 ± 2.2 | 14.9 ± 2.7 | 18.0 ± 6.4 | 16.2 ± 4.2 |
| Sex: Female, Male(Participants) | .014" With Twin Brackets | .016" With Twin Brackets | .014" With Self-ligating Brackets | .016" With Self-ligating Brackets | Total |
|---|---|---|---|---|---|
| Female | 5 | 5 | 6 | 4 | 20 |
| Male | 4 | 4 | 3 | 5 | 16 |
| Race and Ethnicity Not Collected(Participants) | .014" With Twin Brackets | .016" With Twin Brackets | .014" With Self-ligating Brackets | .016" With Self-ligating Brackets | Total |
|---|---|---|---|---|---|
| Count of participants | — | — | — | — | 0 |
| Region of Enrollment(Participants) | .014" With Twin Brackets | .016" With Twin Brackets | .014" With Self-ligating Brackets | .016" With Self-ligating Brackets | Total |
|---|---|---|---|---|---|
| United States | 9 | 9 | 9 | 9 | 36 |
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No
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University of North Carolina, Chapel Hill →