Sonendo GentleWave™ System for Treatment in Molar Teeth Requiring Root Canal Therapy: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Sonendo GentleWave™ System for Treatment in Molar Teeth Requiring Root Canal Therapy (NCT02285595), a na na study. The primary outcome is Number of Participants With a PAI Score of < 3, = 3, or = 4 or 5.

2. Clinical Question

This is a descriptive question about outcomes in a treated group, alongside a stated literature-control context. It is not, on the registered design alone, a randomized comparison of the device against a concurrent traditional-treatment group. The record does not report enough information to assess how any literature-control patients were selected or whether their characteristics and outcome assessments were comparable. Those details matter when interpreting comparisons across separate sources. The central statistical reading is therefore limited: the outcome definition and follow-up time are specified, but the posted record does not provide the endpoint counts or a reported comparative estimate.

3. Trial Design

The study is registered as a prospective, multicenter study comparing healing after treatment with the Sonendo GentleWave™ System against a traditional root canal therapy literature control. Its registered model is single-group, allocation is listed as NA, and masking is listed as NONE. The record describes the intervention as a device and states that it was intended to prepare, clean, and irrigate 1st and 2nd molar teeth indicated for root canal therapy. Enrollment was 69.

The registry record lists the study as completed. The recorded start was 2014-07, and primary completion was 2017-06-22. The study phase is listed as NA. The sponsor is Sonendo, Inc. These administrative details describe the registered study but do not establish how participants were selected, treated, retained, or assessed in practice.

The literature-controlled description should be distinguished from a concurrent randomized trial. A single-group design does not assign participants to competing treatments within the study, and the record does not identify a randomized allocation process. A literature control may offer context, but a comparison with results from other sources can be affected by differences in eligibility, clinical care, outcome measurement, follow-up, or reporting. The registry record does not provide details sufficient to evaluate those factors or establish the nature of the literature-control dataset.

The primary outcome is assessed at 12 months and classifies participants by PAI score: below 3, equal to 3, or equal to 4 or 5. The registry record describes an additional outcome measure but does not provide its details in the information reported for this analysis. It lists two outcome measures and zero analyses. The numerical results for the primary endpoint, the analysis population, and the handling of missing outcome assessments are not reported in the registry record. Consequently, the design and outcome definitions can be described, but the registered information does not support an estimate of the observed healing distribution or a treatment contrast.

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

Reasons for not completing this period:

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.

6. Primary Endpoint

The registry lists the primary outcome as Number of Participants With a PAI Score of < 3, = 3, or = 4 or 5, measured over 12 months.

The primary endpoint is the number of participants in each of three PAI groupings at 12 months: a score below 3, a score equal to 3, or a score equal to 4 or 5. The periapical index is a radiographic scoring system for apical periodontitis. Its categories range from normal appearance and small bone-structure changes through findings associated with bone loss and apical periodontitis. Grouping scores in this way makes the endpoint a count-based description of radiographic status at a specified follow-up time.

The endpoint description also defines “healed” as absence of a radiographic indication of apical periodontitis, expressed as PAI below 3, together with absence of clinical signs and symptoms other than tenderness to percussion. “Healing” is defined as a reduction of radiolucency when it was present at baseline, combined with absence of those clinical signs and symptoms. These definitions distinguish a final radiographic status from improvement relative to baseline.

As a general statistical point, an ordered clinical score can communicate gradations of findings that a simple yes-or-no measure may not preserve. Counts in categories show how participants are distributed across the specified score groups, while a separate healed or healing classification incorporates the stated clinical criteria. The registry record supplies the definitions but does not report the observed category counts, so the actual distribution and the number meeting either definition are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What kind of outcome is being counted?

The primary outcome is expressed as counts of participants in PAI categories. The categories are below 3, equal to 3, and equal to 4 or 5, assessed at 12 months. Although the outcome is reported as counts, the underlying score represents ordered radiographic categories: the descriptions move from normal findings and small structural changes toward findings associated with apical periodontitis. The counts would describe how many participants fall into each defined group; they would not, by themselves, explain why a participant has a given score.

As a general statistical principle, categorical outcomes are often described using counts and proportions. Counts preserve the number of observations in each group, while proportions place those counts in relation to a clearly defined denominator. The registry record gives enrollment of 69, but does not report the denominator assessed for this endpoint or any category counts. It is therefore not possible to interpret an observed distribution or calculate an outcome proportion from the registry record.

What does the endpoint definition add?

The registry record distinguishes “healed” from “healing.” Healed requires absence of a radiographic indication of apical periodontitis, corresponding to PAI below 3, and absence of clinical signs and symptoms other than tenderness to percussion. Healing instead requires a reduction of radiolucency when it was present at baseline, together with absence of those clinical signs and symptoms. The first definition describes a specified final status; the second includes change from baseline for participants with baseline radiolucency.

These distinctions are important because a radiographic score and a combined clinical-radiographic classification are not necessarily identical outcomes. A participant’s classification under the healing definition depends on baseline radiolucency, while the primary endpoint title groups participants by their 12-month PAI score. The registry record does not report the counts meeting either definition or further details about how assessments were conducted.

How should the study structure shape interpretation?

The registry record classifies the study as single-group, with allocation listed as NA and masking as NONE. The intervention was the Sonendo GentleWave™ System, described as intended to prepare, clean, and irrigate molar teeth undergoing root canal therapy. The study is also described as literature controlled, naming traditional root canal therapy as the literature-control context. This is not a concurrent randomized treatment comparison in the registered design.

As a general statistical principle, random allocation can help balance measured and unmeasured prognostic factors between treatment groups. A comparison to a literature control does not obtain that protection through allocation within the study. Its credibility depends on the comparability of the people, clinical context, outcome definitions, follow-up, and data collection across sources. Details needed to evaluate that comparability are not reported in the registry record. No comparative effect estimate is reported either.

What can be said about statistical analysis?

The registry record lists two outcome measures and zero analyses. It does not report an analysis plan, a model for estimating an outcome, adjustment variables, or inferential results. No standard error, confidence interval, or p-value for the primary outcome is reported in the registry record. The result should not be reconstructed from the enrollment figure, since enrollment does not provide the endpoint counts or the number assessed.

As a general statistical principle, an estimate and its uncertainty answer different questions. An estimate describes the observed result, while an uncertainty interval indicates the precision associated with that estimate under a specified method and assumptions. A p-value, when used, addresses compatibility between data and a stated null model; it does not measure clinical importance or provide the probability that a treatment works. None of these inferential quantities is reported for the primary endpoint in the registry record, so these concepts explain what such analyses could convey, not what this study demonstrated.

Over-dispersion is a general issue when count variation is greater than a chosen statistical model expects. If counts are analyzed using a model that assumes less variability than the data have, uncertainty may be understated. The registry record does not report a count model or a dispersion assessment, and the primary outcome is described as counts of participants across categories rather than as a modeled event rate. Thus, over-dispersion is a general consideration, not a reported feature of this study.

How should planning illustrations be read?

The record’s sample-size assumptions describe a planning illustration based on the observed effect, not the trial’s own design. The stated assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the effect to detect expressed as a fraction of the observed effect. Such illustrations are hypothetical planning calculations; they are not evidence about the number of participants actually analyzed, and they are not observed power.

As a general statistical principle, planning calculations depend on the assumed effect, variability, allocation, and analysis method. Changing an assumed effect changes the planning question. An illustration based on a fraction of an observed effect does not establish that the trial was designed with that target or that it had a particular probability of detecting an effect. The registry record does not report the trial’s own sample-size justification. No numerical planning result should be confused with an observed endpoint result.

10. Multiplicity, Missing Data and Analysis Populations

The registry record lists two outcome measures, but only the primary endpoint is described in the information available for this analysis. The other outcome’s definition, timing, and results are not reported in the registry record. The record lists zero analyses and does not report a statistical analysis plan, including whether any multiplicity strategy was prespecified. It is therefore not possible to determine how multiple outcomes or analyses were handled, or whether any inferential findings were adjusted for multiple testing.

As a general statistical principle, evaluating multiple outcomes or repeated analyses can increase the chance of at least one apparently notable result when each is interpreted without accounting for the broader analysis context. A prespecified analysis strategy helps readers understand which comparisons were primary and how secondary findings should be interpreted. No such strategy is reported in the registry record, so no claim about multiplicity control is warranted.

The amount of missing outcome data is also not reported in the registry record. Enrollment was 69, but the number with an observed 12-month PAI score, the number excluded from analysis, and reasons for any unavailable assessments are not given. Methods for handling missing data, including any assumptions or sensitivity analyses, are not reported. The analysis population is not reported in the registry record, so it is unclear whether the registered endpoint was analyzed among all enrolled participants or a subset.

As a general statistical principle, missingness can affect both the denominator and the interpretation of an outcome if participants without observed assessments differ from those with assessments. Without endpoint denominators and a description of missing-data handling, readers cannot assess the potential impact. The registry record does not provide enough information to establish that missing data were absent or to judge how they were addressed.

11. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 5% reporting threshold.

The registry record reports one treatment group, titled GentleWave™ Treatment Group. It lists 69 participants at risk for serious adverse events and 0 with a serious adverse event. It also lists 69 participants at risk for other adverse events and 0 with an other adverse event. Deaths are listed as 0. No top serious adverse-event terms are reported.

These are registry-reported counts, not a detailed account of every event or the length of each participant’s observation. The record does not provide additional event descriptions, severity details, attribution assessments, or follow-up information for interpreting the safety counts. The listed at-risk numbers should not be assumed to be the endpoint analysis population; the registry record does not report whether those populations coincide.

As a general statistical principle, a zero count in a study group describes what was recorded in that group, but does not establish that an event is impossible or that no unrecorded event occurred. Interpretation depends on how events were defined, collected, monitored, and reported, as well as on the amount of observation. Those details are not reported in the registry record. The figures should therefore be read narrowly as the posted adverse-event counts, rather than as proof of absence of risk or as a comparative safety estimate.

12. What the Result Does, and Does Not, Mean

The registered information establishes that a prospective, multicenter, single-group study evaluated the Sonendo GentleWave™ System in molar teeth indicated for root canal therapy. It defines a 12-month primary endpoint based on PAI categories and describes criteria for healed and healing. Enrollment was 69, and the study status is completed. These details make the study question and the intended outcome understandable.

They do not establish the observed healing result. The primary endpoint counts are not reported in the registry record, nor are an effect estimate, confidence interval, or p-value. Without the counts and denominator assessed at follow-up, the extent and precision of the observed outcome cannot be determined from the posted record. Completion status and enrollment alone do not fill that gap.

The record also does not support a causal treatment comparison with traditional root canal therapy. The study is registered as single-group, with allocation listed as NA, and traditional treatment is described as a literature control. The registry record does not report the control data or a comparative analysis. As a general statistical principle, comparisons across separate datasets may be affected by differences in participant selection, clinical context, outcome definitions, and follow-up. The reported design does not remove those concerns through random assignment.

The adverse-event counts are also limited: the record lists 0 serious adverse events, 0 other adverse events, and 0 deaths in the treatment group, alongside the reported at-risk counts. These values describe recorded counts but do not quantify comparative risk or establish that an event cannot occur.

The appropriate conclusion is that the registry record specifies a study design and outcome framework but does not report the primary numerical results or a comparative treatment estimate. It therefore cannot establish from the posted information how participants’ PAI scores were distributed, how precise any healing estimate was, or whether outcomes differed from traditional therapy.

13. Why This Trial Matters Statistically

This study is statistically instructive because its title describes a comparison, while its registered model is single-group and its allocation is listed as NA. That distinction matters: a study can use a literature-control context without being a randomized, concurrent comparison. Readers need to identify the source and structure of a comparator before interpreting a treatment contrast as causal.

The primary endpoint also illustrates why outcome definitions matter. PAI categories provide a radiographic description at 12 months, while the registry’s healed and healing definitions combine radiographic information with clinical signs and symptoms. Healing additionally depends on reduction of radiolucency when it was present at baseline. These distinctions affect what the counts represent and what information would be needed to reproduce or interpret a classification.

The posted record demonstrates a separate reporting issue: design details and endpoint definitions are available, but numerical primary results and inferential analyses are not reported. Enrollment of 69 does not reveal how many participants had an endpoint assessment, how outcomes were distributed, or how uncertain an estimate would be. In a clinical study, those details are necessary to move from a stated question to an interpretable estimate.

Finally, the adverse-event counts show why zero observed events should be read in context. The registry record lists zero events in the reported categories, but does not provide detailed collection or follow-up information. As a general statistical lesson, a count is meaningful only alongside its population, observation, and ascertainment context. This record offers useful design and definition information, while also showing how missing results and analysis details constrain statistical interpretation.

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 main limitation for interpreting this particular study from the registry record is the absence of numerical primary outcome results. Although the endpoint and its 12-month timeframe are defined, the counts in the PAI categories are not reported. The number of participants with an observed primary outcome is also not reported, so the enrolled population cannot be treated as the endpoint denominator.

The registered single-group design limits comparative interpretation. Traditional root canal therapy is identified as a literature control, but details of that control, its data source, eligibility, outcome assessments, and follow-up are not reported in the registry record. The record therefore does not permit assessment of comparability between the treated group and the literature-control context. Allocation is NA and masking is NONE, so the registered design does not describe randomized allocation or masking.

The registry record lists two outcome measures but provides no analysis results and lists zero analyses. The secondary outcome details, the analysis population, missing-data handling, statistical methods, and any multiplicity approach are not reported. The study’s own sample-size justification is not reported in the registry record. These omissions prevent assessment of the precision, robustness, and completeness of the outcome analysis.

The safety record lists zero serious adverse events, zero other adverse events, and zero deaths, but does not report detailed event descriptions, ascertainment procedures, or observation information. Those counts should not be expanded into broader safety claims. These limitations are specific to what the registry record reports; they do not establish that the omitted methods or results were absent from all study documentation.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Sonendo GentleWave™ System for Treatment in Molar Teeth Requiring Root Canal Therapy — NCT02285595.
• Registry record last updated 2023-01-31; status last verified 2023-01.
• Results first posted 2023-01-31.
• 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.

18. Record Summary

NCT02285595 is a completed prospective, multicenter, single-group study of the Sonendo GentleWave™ System for molar teeth indicated for root canal therapy. The registry record lists enrollment of 69, a start of 2014-07, primary completion on 2017-06-22, allocation as NA, and masking as NONE. Traditional root canal therapy is described as a literature control.

The primary endpoint is the number of participants in PAI categories below 3, equal to 3, or equal to 4 or 5 at 12 months. The registry record describes healed and healing criteria but does not report the observed primary outcome counts, endpoint denominator, or inferential results. It lists two outcome measures and zero analyses.

The adverse-event record lists 0 serious adverse events, 0 other adverse events, and 0 deaths in the treatment group. The design and outcome framework are described, but the missing numerical outcome and comparative results limit interpretation of healing and treatment differences.