This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for The Use of Clear Aligners With Movement Enhancement Techniques (NCT02087163), a na na study. The primary outcome is Tooth Movement Change.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02087163 |
| Phase | NA |
| Condition | Malocclusion |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 90 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Align Technology, Inc. |
| Results posted | Yes |
2. Clinical Question
Population
People with malocclusion who completed orthodontic treatment. The primary outcome population is described as all completed subjects; the registry record lists enrollment of 90.
Intervention
Clear aligners used with a movement enhancement technique. The registry lists both as devices and describes the study arm as the movement enhancement technique clear aligner.
Comparator
No separate comparator group is described. The record identifies a single-group model and does not report a randomized allocation.
Primary question
What was the mean tooth movement change, measured in millimeters of movement per aligner, from baseline to the end of treatment? The registry describes an expected average treatment duration of 78 weeks, but does not report the outcome estimate or its confidence interval.
This is a question about observed tooth movement during treatment in the described group. It is not a registered head-to-head question about whether the enhancement technique performs differently from aligners alone or from another treatment. Without a separate comparator, changes over treatment cannot be separated from other influences using a between-group contrast.
The record also lists length of treatment change as a secondary outcome. It does not give a result for that outcome. Thus, although the registry identifies outcomes and describes their intended measurement, it does not provide numerical findings with which to assess the magnitude or precision of the observed changes.
3. Trial Design
The registry describes a completed, single-group study of clear aligners with a movement enhancement technique for malocclusion. Enrollment is listed as 90. Allocation is recorded as NA, and masking is recorded as none. The study is not described as randomized, and no separate control group is listed. Its design therefore describes treatment in one group rather than a like-for-like comparison between assigned groups.
The intervention entries identify a movement enhancement technique and a clear aligner, both classified as devices. The arm description refers to the movement enhancement technique clear aligner. The registry does not describe a separate arm receiving clear aligners without the technique, so such a comparison should not be inferred from the intervention names.
The primary outcome is tooth movement change, measured in millimeters of tooth movement per aligner. Its timeframe is baseline and end of treatment, with an average duration of 78 weeks stated in the record. Participants are described as followed for the duration of orthodontic treatment, and the primary outcome population is all completed subjects. Length of treatment change is listed as a secondary outcome.
The study status is completed. The record lists a start of 2014-02 and primary completion of 2018-12. These administrative details do not establish when an individual participant began or ended treatment. The registry record does not report a detailed protocol, the rationale for the enrollment target, or the statistical plan used to analyze the outcomes. It also lists no analyses. As a result, the design and intended measurements can be described, but the specific analysis procedures and numerical outcome findings cannot be assessed from the registry record.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Overall Study
| Stage | Movement Enhancement Technique |
|---|---|
| STARTED | 90 |
| COMPLETED | 73 |
| NOT COMPLETED | 17 |
Analysis population for the primary outcome, as defined in the registry: all completed subjects
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
| Characteristic | Unit | Movement Enhancement Technique |
|---|---|---|
| Participants analysed | 90 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 90 |
| Age, Categorical: >=65 years | Participants | 0 |
| Sex: Female, Male: Female | Participants | 70 |
| Sex: Female, Male: Male | Participants | 20 |
| Race and Ethnicity Not Collected | Participants | — |
| Region of Enrollment: United States | participants | 90 |
6. Primary Endpoint
The registry lists the primary outcome as Tooth Movement Change, measured over Baseline and end of treatment, an average of 78 weeks.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | 95% Confidence Interval |
| Unit | millimeters |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is tooth movement change. The registry defines it as the number of millimeters of tooth movement per aligner and specifies measurement from baseline to the end of treatment. It describes the summary measure as a mean with a 95% confidence interval. The intended observation period is the duration of orthodontic treatment, stated to be an expected average of 78 weeks.
A continuous measure such as millimeters can describe the amount of movement on a scale rather than assigning participants to broad categories. A mean gives a summary of the measurements in the analysis population. A confidence interval, in general, communicates uncertainty around an estimated quantity; it does not show the full spread of individual measurements. The width and location of an interval would be needed to judge the estimate’s precision and plausible values.
The outcome is relevant to the study’s stated purpose of measuring tooth movement during aligner treatment. However, the registry record does not report the mean or its confidence interval. It therefore does not allow readers to assess the recorded magnitude, variability, or precision of tooth movement change. The endpoint definition alone is not an outcome result.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies a completed single-group study and defines a primary measure of tooth movement change, but it does not report a numerical estimate for that measure. Although the primary outcome is described as a mean with a 95% confidence interval, neither the mean nor the interval is reported in the registry record. The description of an outcome and its intended summary cannot substitute for the result itself.
This absence limits interpretation at the most basic level: the magnitude of the observed mean change is not available. Without an estimate and its confidence interval, the precision of the result cannot be evaluated either. A confidence interval is useful because it reflects uncertainty around an estimate; without its endpoints, readers cannot judge whether the registry result is tightly or broadly estimated. No inference about the outcome’s direction or size is warranted from the endpoint definition alone.
The design also shapes what a result could establish. A single group receiving clear aligners with the movement enhancement technique can describe measurements observed in that group over treatment. It does not provide a separate control group for estimating a between-group treatment contrast. The registry lists no randomized allocation and no comparator arm. Consequently, even if a within-group change estimate were available, it would not by itself establish what would have happened under a different treatment or without the enhancement technique.
The registry lists length of treatment change as a secondary outcome but reports no result for it. It lists two outcome measures and no analyses. The registry record does not report whether estimates were adjusted, how missing measurements were handled, or which analysis population was used beyond describing the primary population as all completed subjects. Those omissions prevent assessment of how participant completion, data availability, or analysis choices may have influenced the findings.
The safety record lists 90 at risk for serious adverse events and zero affected; it also lists 90 at risk for other adverse events and zero affected, with zero deaths. These are registry-reported counts. They do not establish that every possible adverse event was captured or that the observation period and reporting procedures were sufficient to rule out uncommon events. The record does not give further safety detail or serious-event terms.
Overall, the registry provides design and outcome definitions, but not the numerical clinical outcome findings needed for an effectiveness interpretation. Its completed status should not be mistaken for public reporting of results. The available record supports describing the planned measurement and listed safety counts, not a conclusion about treatment benefit or lack of benefit.
9. Statistical Methods Explained
What does a mean describe?
For a continuous endpoint, a mean is a way to summarize measurements on a numerical scale. In this study the scale is millimeters of tooth movement per aligner, and the registry names the mean as the summary measure. A mean is informative about the central level of the recorded measurements, but it does not describe every participant’s experience. Individual measurements can differ, and the mean alone does not convey their full distribution.
The outcome is defined as change between baseline and the end of treatment. A change measure uses observations at both time points. Interpreting it depends on having usable measurements from the relevant time points and a clear rule for deriving the change. The registry record gives the intended time points and measure, but does not report further calculation details or an analysis description. It also does not report the numerical mean.
What does a 95% confidence interval convey?
In general, a confidence interval expresses uncertainty around an estimated quantity under the assumptions of the statistical method used. The interval is not a display of all individual results and does not guarantee that a particular value is the true value. Its width is important: a narrower interval indicates greater precision under the method, while a wider interval indicates more uncertainty. The registry describes a 95% confidence interval for the primary mean but gives no interval limits. Precision therefore cannot be evaluated from this record.
The record does not state how the interval was calculated. Different procedures can rely on different assumptions about the data and the sampling process. It would be inappropriate to infer a particular procedure, distributional assumption, or adjustment method when none is reported.
How does the single-group design affect interpretation?
A single-group study can report measurements made in the treated group over time. It does not directly estimate a difference between that group and a concurrent comparator. In general, a before-and-after change can reflect the treatment course alongside other influences, and the design alone does not disentangle them. Here, allocation is listed as NA, masking as none, and the model as single group. No like-for-like control comparison is described.
This distinction matters because a within-group change and a treatment contrast answer different questions. A change from baseline describes how measurements in the group differ over time. A contrast between groups estimates how outcomes differ between the treatment strategies represented by those groups. The registry record does not report the latter design. The outcome definition should therefore be read as a measurement plan, not as evidence of a comparative effect.
What can be inferred from the analysis information?
The record lists two outcome measures and zero analyses. It names tooth movement change as the primary outcome and length of treatment change as a secondary outcome, but provides no outcome estimates. It does not identify a statistical model, covariate adjustments, a method for accounting for repeated measurements, or a procedure for constructing the confidence interval. Such details are not reported in the registry record and should not be assumed.
The primary population is described as all completed subjects. This identifies the stated population for the endpoint, but does not explain how completion was defined, whether everyone in that population had usable endpoint data, or how incomplete observations were treated. The registry record does not report a missing-data method or a sensitivity analysis. In general, missing observations can affect an estimate when the participants with available measurements differ from those without them; assessing that issue requires information about missingness and the analysis approach.
How should the planning description be read?
The record describes a planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It states that the effect to detect is a stated fraction of the observed effect. These assumptions describe a hypothetical planning calculation, not the single-group design listed for the study. No numerical planning estimates are reported in the registry record, and no observed effect estimate is available there to evaluate the illustration.
In general, sample-size planning asks how much information a future study would need under specified assumptions. It is not a result about the precision actually achieved in a completed study, and it is not observed power. A calculation based on an observed effect also depends on that effect estimate and the chosen planning assumptions. Because the registry record does not give numerical planning results or an outcome estimate, neither can be assessed. The two-arm equal-allocation setup should not be mistaken for evidence that the trial itself used two arms.
10. Multiplicity, Missing Data and Analysis Populations
The registry identifies tooth movement change as the primary outcome and length of treatment change as a secondary outcome. It lists two outcome measures, but does not report analyses. The registry record does not describe a multiplicity adjustment, a hierarchy of hypotheses, or a plan for interpreting multiple statistical tests. Without the analysis details and results, it is not possible to determine whether or how the study addressed the possibility of false-positive findings across outcomes. No significance tests are reported in the record.
The primary outcome population is described as all completed subjects. The registry does not explain how completion was defined or whether the stated population includes every enrolled participant. It does not report the number with available measurements for either time point, the extent or pattern of missing outcome data, or how missing values were handled. It also does not report an analysis population for the secondary outcome.
In general, missing data matter because an analysis of available measurements may represent participants with observed data rather than everyone intended for assessment. Whether this could affect an estimate depends on why measurements are missing and on the analysis approach. No assumptions or sensitivity analyses addressing missing data are reported in the registry record. The effect of missingness on the findings therefore cannot be evaluated.
The record also does not describe prespecified analysis procedures or explain whether the reported outcome definitions were changed. These details are not reported in the registry record. With outcome estimates and analysis methods absent, readers cannot assess the handling of multiplicity, missing observations, or deviations from an intended analysis plan.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Movement Enhancement Technique | 0 | 90 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Movement Enhancement Technique | 0 of 90 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Movement Enhancement Technique | 0 of 90 |
The registry lists 90 participants at risk for serious adverse events and zero affected. For other adverse events, it also lists 90 at risk and zero affected. Deaths are listed as zero, and no top serious-event terms are given. These are the safety counts recorded for the movement enhancement technique group.
A zero count means that no affected participants are recorded in the relevant category in this registry entry. It does not prove that an event is impossible or that all events were detected. The record does not give additional detail on event definitions, collection procedures, follow-up completeness for safety, or the timing of adverse-event assessment. The treatment observation period is described as the duration of orthodontic treatment, expected to average 78 weeks, but further safety-specific follow-up information is not reported in the registry record.
The counts should be read as descriptive registry entries, not as a comparison of safety between treatments: no separate comparator group is listed. They also do not provide information about event severity beyond the serious-event category, or about events that may not have been captured or entered. The zero entries are therefore limited to what the record reports.
12. What the Result Does, and Does Not, Mean
The record establishes that a completed single-group study was registered to examine tooth movement during clear-aligner treatment with a movement enhancement technique. It defines tooth movement change in millimeters per aligner as the primary outcome and specifies baseline and end of treatment as the measurement points. It also names length of treatment change as a secondary outcome. These details clarify what the study set out to measure.
The record does not report numerical findings for either outcome. There is no reported mean tooth movement change, confidence interval, or secondary-outcome estimate. Consequently, the magnitude and precision of the observed outcome cannot be determined from the registry record. The record’s completed status is not itself evidence about what the measurements showed.
The design also limits the type of conclusion that could be drawn. The study is described as single group, with allocation recorded as NA and no separate comparator. A measurement of change within this group would not alone establish how the outcome compares with another treatment or with aligners without the enhancement technique. The record does not support a causal comparative conclusion.
The registry lists zero affected participants for serious and other adverse events and zero deaths among the listed at-risk group. Those entries describe the recorded counts, but do not establish that no event could occur or provide a comparative safety estimate.
In short, the registry record supports a description of the research question, design, intended outcomes, and recorded safety counts. It does not provide the results needed to judge the observed tooth movement or treatment duration, and it does not permit a conclusion that the treatment works or does not work.
13. Why This Trial Matters Statistically
This trial is statistically important to read as a measurement study rather than a comparative trial. The registry describes one group receiving clear aligners with a movement enhancement technique, and it identifies tooth movement change over treatment as the primary outcome. That distinction prevents a within-group measurement from being interpreted as a comparison with an alternative treatment that is not described in the record.
The outcome is continuous and has a clinically interpretable unit: millimeters of movement per aligner. The registry specifies a mean and 95% confidence interval, which in general would allow readers to consider both the estimated average and its precision. But neither estimate is reported. This highlights the difference between a clear outcome definition and an interpretable result: measurement plans alone do not show the observed magnitude or uncertainty.
The record also illustrates why analysis transparency matters. It identifies a primary and a secondary outcome, but lists no analyses and provides no statistical methods for missing data, interval construction, or multiplicity. Those omissions leave important questions about how measurements were summarized and how uncertainty was assessed unanswered.
Finally, the planning description refers to a hypothetical two-arm, equal-allocation calculation, while the registered study model is single group. Keeping planning assumptions separate from the actual design avoids treating a planning illustration as evidence of the trial’s allocation, power, or observed results. The record’s value is in documenting the intended question and measurements; its limits are the absence of outcome estimates and analysis details.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The central limitation for interpreting this trial record is that numerical outcome results are not reported. The primary mean and 95% confidence interval are absent, as is the result for length of treatment change. Without estimates, the size and precision of the measured outcomes cannot be assessed.
The design is single group, and the registry does not identify a separate comparator. Allocation is recorded as NA and masking as none. Accordingly, the record does not describe a randomized, masked comparison that could estimate a contrast with another treatment. Any within-group measurements would not by themselves isolate the contribution of the movement enhancement technique.
The primary outcome population is described as all completed subjects, but the record does not explain completion or report how many participants had usable measurements at the relevant time points. Missing-data procedures, analysis populations for the secondary outcome, and sensitivity analyses are not reported in the registry record. Statistical methods for the mean and confidence interval are also not described.
The registry lists zero affected participants for serious adverse events, zero for other adverse events, and zero deaths. Further information about event ascertainment and safety follow-up is not reported in the registry record. These counts therefore cannot answer questions beyond the entries recorded.
Although the registry describes planning assumptions for a two-arm calculation, numerical planning estimates are not reported. That hypothetical framework does not match the single-group model described for the study and cannot be used to infer the study’s actual statistical power or design justification. A sample-size rationale and interim-analysis plan are not reported in the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: The Use of Clear Aligners With Movement Enhancement Techniques — NCT02087163.
- Registry record last updated 2020-01-31; status last verified 2020-01.
- Results first posted 2019-04-24.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
NCT02087163 is a completed, single-group study of clear aligners with a movement enhancement technique for malocclusion. Enrollment is listed as 90; allocation is NA and masking is none. The record identifies tooth movement change, measured in millimeters per aligner from baseline to end of treatment, as the primary outcome, with a mean and 95% confidence interval specified. The expected average treatment duration is 78 weeks. Length of treatment change is listed as a secondary outcome.
Numerical results for the primary and secondary outcomes are not reported in the registry record, and the record lists no analyses. It describes the primary population as all completed subjects. Safety entries list zero affected for serious and other adverse events and zero deaths. The available information describes the design, intended measurements, and recorded safety counts, but does not provide outcome estimates for interpretation.