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 Investigation of the Safety and Efficacy of Pocket-X Gel (NCT03358251), a na na study. The primary outcome is Change in Periodontal Pockets Probing Depth.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03358251 |
| Phase | NA |
| Condition | Periodontal Pocket |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 34 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Tree of Life Pharma Ltd. |
| Results posted | Yes |
2. Clinical Question
Population
The registry record describes participants with periodontal pockets. Enrollment is listed as 34. It does not report eligibility criteria, baseline characteristics, or the characteristics of participants who contributed to any outcome analysis.
Intervention
Pocket-X Gel was applied to periodontal pockets in one or two mouth segments after scaling and root planing (SRP) across the entire mouth. The gel is described as a periodontal in-situ gelling product. The registry record does not report the application procedure in greater detail.
Comparator
The contralateral mouth segment or segments served as the control, receiving SRP only. This creates a within-participant comparison of treated and control pockets. Allocation is listed as not applicable, and the comparison is not described as randomized.
Primary question
The primary outcome is change in periodontal pocket probing depth, measured in millimeters at 12 and 24 weeks following the first Pocket-X Gel administration. The question is whether change in pockets treated with SRP plus Pocket-X Gel differs from change in pockets treated with SRP only. The registry record does not report the observed changes, an estimated contrast, or an analysis of this question.
These design details define the clinical question, but they do not establish what the outcome was. Because both treatment conditions occur within the same participant, a useful comparison would account for the paired structure rather than treat every pocket as independent. The registry record does not report how many pockets or mouth segments were evaluated, how the comparison was calculated, or which participants and pockets were included in the endpoint analysis. Those omissions limit interpretation of the comparison and its precision.
3. Trial Design
The study is listed as completed and as a single-group study. Its description is an open-label split-mouth study: SRP was performed across the entire mouth, while Pocket-X Gel was applied to pockets in one or two mouth segments; contralateral segment or segments served as control with SRP only. Thus, the treatment contrast is within participants, even though the registry classifies the trial as single-group. The registry record does not describe a separate parallel control group.
Allocation is listed as not applicable, and the registry’s design note states that this is not a randomized comparison. Masking is listed as none, consistent with the open-label description. The record does not report whether outcome assessors were masked, how the treated and control segments were selected, or how the location of treated pockets was determined. These details matter because the absence of participant masking does not by itself establish whether measurements were made without knowledge of treatment.
Enrollment is listed as 34. This is an enrollment figure, not a reported count of participants included in an endpoint analysis. The registry record does not report the analyzed participant count, the number of pockets measured, or whether all enrolled participants completed follow-up. The listed study start date is 2018-03-12, and primary completion is listed as 2019-12-30. The study status is completed.
The primary outcome is change in probing depth at 12 and 24 weeks following the first Pocket-X Gel administration. Secondary outcomes are change in clinical attachment, recession level, bleeding index, and mobility grade. The record lists five outcome measures but zero analyses. It does not report the statistical methods used, the result estimates, confidence intervals, or p-values. Consequently, the design can be described, but the registry record does not permit a conclusion about the size or precision of any 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
| Stage | SRP+Pocket-X Gel, Split-mouth |
|---|---|
| STARTED | 34 |
| COMPLETED | 34 |
| NOT COMPLETED | 0 |
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 | SRP+Pocket-X Gel, Split-mouth |
|---|---|---|
| Participants analysed | 34 | |
| Age, Continuous | years | 51.3 (SD 13.1) |
| Sex: Female, Male: Female | Participants | 13 |
| Sex: Female, Male: Male | Participants | 21 |
| Race and Ethnicity Not Collected | Participants | — |
| Region of Enrollment: Israel | participants | 34 |
6. Primary Endpoint
The registry lists the primary outcome as Change in Periodontal Pockets Probing Depth, measured over 12 and 24 weeks following first Pocket-X Gel administration.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | mm |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is change in periodontal pocket probing depth, expressed in millimeters. Probing depth measures the distance from the gingival margin to the bottom of the periodontal pocket. The registry describes comparing change in pockets treated with SRP plus Pocket-X Gel against change in pockets treated with SRP only. Measurements are specified at 12 and 24 weeks following the first gel administration.
Change is used to describe how a measurement differs from its earlier value over follow-up, rather than relying only on a single later measurement. A comparison of change between treatment conditions can therefore address whether pocket-depth trajectories differ over the stated follow-up. The record does not specify the baseline measurement definition, whether change is calculated at the participant or pocket level, or how multiple pockets within a mouth segment are combined.
In general, probing depth is a continuous outcome, and its mean describes the average measurement or average change in the analyzed group. The registry identifies the parameter as a mean and the dispersion as standard deviation. A standard deviation describes variation among observations; it does not by itself quantify the precision of a treatment contrast. Precision would require an estimate and an uncertainty measure, such as a confidence interval. No primary-endpoint estimates, standard deviations, confidence intervals, or p-values are reported in the registry record, so the endpoint’s observed magnitude and precision cannot be assessed.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies the primary outcome and the intended within-mouth contrast, but it does not report the primary results. There is no posted estimate of change in probing depth for either treatment condition, no estimate of the difference in change, and no confidence interval or p-value. The record also lists zero analyses. Therefore, the size, direction, and precision of the primary comparison are not reported in the registry record. The absence of these results is not evidence that the groups had the same outcome or that one condition was better.
The split-mouth structure is central to interpreting any eventual result. Each participant contributes treated and control mouth segments, so observations from the two conditions within a participant are related. In general, a paired comparison can account for shared participant characteristics and may be more informative than a comparison that treats the two sides as unrelated. However, pockets within a mouth segment may also be related to each other. The registry record does not report the unit of analysis or how within-participant and within-segment dependence was handled.
The record describes the study as open-label and explicitly indicates that allocation was not randomized. This means the contrast should not be interpreted as a randomized treatment effect. In general, selecting which segments receive the gel can introduce systematic differences between treated and control pockets. Differences in starting pocket depth, location, or other characteristics could affect observed change. Whether such differences were present, and whether an analysis adjusted for them, is not reported in the registry record.
Follow-up is specified at 12 and 24 weeks after the first administration. These are separate assessment times, and an estimate at one time does not automatically describe the other. The record does not report whether both time points were analyzed, how repeated measurements were handled, or whether a primary time point was selected for inference. It also does not report missing outcome data or the number of observations available at either time.
Accordingly, interpretation should remain limited to what the registry describes: an intended comparison of probing-depth change after SRP with and without Pocket-X Gel in a split-mouth setting. The completed status and enrollment figure do not substitute for outcome estimates. Without posted endpoint results and methods, clinical magnitude, statistical uncertainty, and the robustness of the comparison cannot be judged.
9. Statistical Methods Explained
The registry record gives a mean and standard deviation as the summary approach for the continuous primary outcome, but it does not report the analysis used to compare treatment conditions. The following explains relevant statistical concepts in general; it does not establish which methods were used in this study.
What does a mean describe?
For a continuous measure such as probing depth, the mean is an average across the observations included in an analysis. When the outcome is change from baseline, the mean change describes average movement in the measure among the included observations. A mean is useful for communicating an overall level, but it can conceal variation: participants or pockets may have changes that differ substantially from the average.
The standard deviation describes the spread of individual observations around their mean. It is not the same as the standard error, which describes the uncertainty in an estimated mean, and it is not a confidence interval. A standard deviation can help characterize variability, but a treatment comparison also needs an estimate of the contrast and a measure of its uncertainty. The registry record does not report these endpoint statistics.
Why does the split-mouth structure matter?
In a split-mouth design, treated and control sites belong to the same participant. In general, outcomes from sites in one person tend to share characteristics and are therefore not necessarily independent. A paired analysis compares treatment conditions within each participant, preserving that relationship. Another suitable approach might model observations with participant-level dependence. The appropriate method depends on how many sites are measured and how the data are organized.
Counting each pocket as if it came from an unrelated participant can make uncertainty estimates too small when pockets within a person are correlated. This is a general concern with clustered data. The registry record does not say whether the analysis unit was the participant, mouth segment, or pocket, or whether clustering was accounted for. The number of pockets and segments analyzed is also not reported in the registry record.
How should repeated follow-up be considered?
The primary outcome is scheduled at 12 and 24 weeks following the first gel administration. In general, measurements from the same participant at different times are correlated. An analysis can estimate each time point separately or model the repeated measurements jointly, but the choice affects the interpretation and uncertainty. A joint model can use the pattern across follow-up, while separate analyses answer time-specific questions. Neither approach can be attributed to this study because the analysis method is not reported in the registry record.
It is also important to define the change being analyzed. A change score ordinarily depends on a baseline and a follow-up measurement, but the record does not give the baseline timing or formula. It does not state how a participant with a missing measurement at one time point was handled. These details are needed to understand which observations contribute to each result.
What does a confidence interval add?
In general, a confidence interval gives a range of values compatible with the data and the statistical model at a stated confidence level. It communicates precision as well as the estimated direction and magnitude of a contrast. A narrow interval indicates greater precision than a wide interval, though either interval must be interpreted in light of study design and possible bias. No confidence interval or confidence level for the primary comparison is reported in the registry record.
A p-value, when used, describes how compatible the observed data are with a specified null model under its assumptions. It does not measure the size or clinical importance of an effect, and it does not establish that the assumptions are appropriate. No primary p-value or testing procedure is reported in the registry record. The statistical plan, including any adjustment, model specification, or handling of outliers, is not reported in the registry record.
What do the planning assumptions mean?
The record describes planning illustrations based on the observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The effect to detect is described as a stated fraction of the observed effect. These are planning assumptions, not a report of the trial’s own design justification, and such illustrations are not observed power. The registry record does not report the numerical observed effect or numerical planning results.
In general, planning calculations estimate the sample size needed to detect a specified effect under chosen assumptions. Their results depend on the assumed variability, the effect size, allocation, analysis method, and significance level. A calculation based on an observed effect is especially dependent on that estimate and should be read as an illustration, not as proof that a completed study had adequate power. Here, the registry record does not report a sample-size justification or enough endpoint results to independently assess precision.
The equal-allocation assumption between two arms also differs from the described split-mouth structure, where each participant contributes sites under both conditions. The planning assumptions should not be mistaken for the actual allocation or analysis. The registry record does not report an interim analysis plan, a prespecified statistical analysis plan, or any adjustment for multiple outcomes or time points.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists a primary outcome of change in probing depth and four secondary outcomes: change in clinical attachment, recession level, bleeding index, and mobility grade. The primary outcome is assessed at 12 and 24 weeks following the first Pocket-X Gel administration. Multiple outcomes and assessment times can create multiple opportunities to detect an apparent difference. In general, a prespecified testing hierarchy or multiplicity adjustment can help control the chance of false-positive findings when several comparisons are evaluated.
The registry record does not report whether the primary endpoint was assigned to one of the follow-up times for the main inferential test, whether both times were analyzed as primary comparisons, or whether any adjustment for multiple testing was planned or used. It also does not report a statistical analysis plan or analysis results. The presence of multiple listed outcomes does not establish that all were tested, nor does the record establish how any tests were interpreted.
Missing data are another important issue for repeated outcomes. A participant or pocket may have a baseline measurement but lack a later measurement, or may contribute observations at one follow-up but not the other. In general, the amount and pattern of missingness can affect both estimates and uncertainty; the appropriate analysis depends on why observations are missing and on the assumptions made. The registry record does not report missing outcome counts, reasons for missingness, imputation, or sensitivity analyses.
The record also does not report the analysis population, such as which enrolled participants, mouth segments, or pockets were included in each outcome analysis. Enrollment is listed as 34, but that is not an endpoint analysis count. Without these details, it is not possible to determine whether analyses followed a prespecified population or how incomplete follow-up was handled.
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 |
|---|---|---|---|
| SRP+Pocket-X Gel, Split-mouth | 0 | 34 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| SRP+Pocket-X Gel, Split-mouth | 0 of 34 |
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 |
|---|---|
| SRP+Pocket-X Gel, Split-mouth | 0 of 34 |
The registry record lists one group, SRP plus Pocket-X Gel in a split-mouth design, with 34 participants at risk for serious adverse events and 0 affected. It also lists 34 at risk for other adverse events and 0 affected, with 0 deaths. These are the safety counts recorded for the group; they are not efficacy results.
A count of zero affected means that no event in the corresponding registry category is recorded for the listed group. It does not establish that an event is impossible or that risk is absent. In general, the precision of a safety estimate depends on how many people were observed, the duration and completeness of follow-up, and how events were defined and collected. The registry record does not report event definitions, the safety follow-up period, surveillance procedures, or any detailed adverse-event terms.
The at-risk figures should be read as registry counts, not as proof that every enrolled participant completed the same safety follow-up. The record does not report safety analysis populations or missing safety data. It also does not give a detailed account of event severity beyond the serious-event category or provide information about events by treatment side or mouth segment. The listed counts therefore describe what is recorded, while leaving important details about ascertainment and follow-up unreported.
12. What the Result Does, and Does Not, Mean
The registry record establishes the intended comparison: pockets treated with SRP plus Pocket-X Gel versus pockets treated with SRP only, within a split-mouth study. It identifies probing-depth change at 12 and 24 weeks following the first gel administration as the primary outcome. It also records enrollment of 34 and a completed study status. These details describe the study’s question and design, not the outcome of the comparison.
The primary results are not reported in the registry record. There is no treatment-contrast estimate, no direction or size of observed change, and no measure of statistical precision. Therefore, the record does not establish whether the conditions differed, how large any difference was, or how compatible the data were with a range of possible effects. Missing results cannot be interpreted as a null result or as evidence of equivalence.
Even if outcome estimates were available, their meaning would depend on the analysis and design. Because allocation was not randomized and the study was open-label, differences in treated and control sites could reflect factors other than the gel. The paired structure can account for shared participant characteristics when analyzed appropriately, but it does not by itself eliminate differences between the selected mouth segments. The record does not report segment selection, baseline comparability, masking of assessors, or the analysis method.
The safety record lists no affected participants for either serious or other adverse events and no deaths, with 34 listed at risk in each category. These counts describe the registry entries and do not establish that no adverse events occurred outside the recorded categories or observation period. Details of event collection and follow-up are not reported.
Overall, the study description identifies a clinically relevant statistical comparison, but the registry entry does not provide enough results to estimate an effect or assess its precision. The available record should be read as a design and safety-count description, not as a conclusion about efficacy or a complete assessment of safety.
13. Why This Trial Matters Statistically
This study is statistically interesting because it uses a split-mouth design for a comparison of treated and control periodontal pockets. In general, such designs can make within-participant comparisons, which may reduce the influence of characteristics shared by the two sides of a participant’s mouth. At the same time, the paired structure requires an analysis that recognizes dependence between observations. A method that ignores that dependence could misstate uncertainty.
The registry classifies the study as single-group and states that allocation is not applicable, while the study description specifies a treated segment and a contralateral control segment. Reading these details together is important: the intended contrast is not between randomized parallel groups, but between conditions within a participant. The registry explicitly notes that this is not a randomized comparison. Selection of segments and baseline differences may therefore matter when interpreting any estimate.
The primary endpoint is continuous and is assessed at two follow-up times. This raises useful statistical questions about the unit of analysis, repeated measurements, and how results at different times relate to one another. The record identifies a mean and standard deviation as the outcome summary, but does not report the analysis or endpoint results. The example illustrates why a study question and a posted result are different things: a defined endpoint does not by itself reveal the observed effect or its precision.
The registry also lists secondary outcomes and safety counts. Multiple outcomes can complicate interpretation if several tests are conducted, while zero recorded events must be understood in light of event definitions and follow-up. Neither multiplicity handling nor detailed safety ascertainment is reported. These features make the record a useful example of how design structure, analysis detail, and transparent reporting all contribute to 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 principal limitation of interpretation is that the registry record does not report primary or secondary outcome estimates or analyses. Without results, the magnitude and precision of the intended treatment comparison cannot be assessed. The record lists five outcome measures and zero analyses, but does not provide endpoint-level results, confidence intervals, or p-values.
The study is open-label, and allocation is listed as not applicable. The registry describes a split-mouth comparison and says the comparison is not randomized. Segment selection could therefore be associated with characteristics that also influence pocket-depth change. Whether treated and control pockets were comparable at baseline, and whether any analysis adjusted for differences, is not reported in the registry record. Masking of outcome assessors is also not reported.
The unit of analysis and the handling of dependence are unclear. The record does not report the numbers of pockets or segments assessed, how measurements within segments were summarized, or whether participant-level pairing and clustering were included in the analysis. These details affect both the interpretation of an estimate and the accuracy of its uncertainty.
Follow-up is specified at 12 and 24 weeks after first administration, but the record does not report endpoint-specific availability, missingness, reasons for missing observations, or the analysis population. It also does not report how change was defined or whether both follow-up times were treated as primary comparisons. The statistical plan and any multiplicity adjustment are not reported in the registry record.
The safety entries show zero affected participants in the recorded event categories, but event definitions, surveillance procedures, and the safety follow-up period are not reported. Enrollment is listed as 34, yet the record does not establish that this number contributed to each efficacy analysis or completed identical safety follow-up. These limitations leave the design understandable but the outcome evidence and its precision unassessable from the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Investigation of the Safety and Efficacy of Pocket-X Gel — NCT03358251.
- Registry record last updated 2020-09-02; status last verified 2020-08.
- Results first posted 2020-09-02.
- 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.
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18. Record Summary
The registry record describes a completed, open-label split-mouth study of Pocket-X Gel following SRP for periodontal pockets. SRP was performed across the mouth, and Pocket-X Gel was applied to pockets in one or two segments; contralateral segments served as SRP-only control. The study is classified as single-group, and allocation is listed as not applicable. The registry states that the comparison is not randomized.
Enrollment is listed as 34. The primary outcome is change in probing depth, measured in millimeters at 12 and 24 weeks following the first gel administration. Four secondary outcomes are listed. The registry record does not report outcome estimates or analyses.
For the split-mouth group, the record lists 34 at risk and 0 affected for serious adverse events, 34 at risk and 0 affected for other adverse events, and 0 deaths. Detailed event definitions and follow-up information are not reported in the registry record.