The Efficacy of an Occluding Dentifrice in Providing Relief From Dentinal Hypersensitivity (DH): Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for The Efficacy of an Occluding Dentifrice in Providing Relief From Dentinal Hypersensitivity (DH) (NCT02924350), a randomized na study. The primary outcome is Change From Baseline in Schiff Sensitivity Score on Day 3.

2. Clinical Question

3. Trial Design

This was a randomized, parallel-group, single-center study with single masking. The registry record lists an enrollment of 205 participants and a completed study. The listed study start was 2016-11-07, and primary completion was 2017-03-17. The registry record does not identify who was masked, so the meaning of “single” masking cannot be specified further.

Participants were assigned to a test dentifrice containing stannous fluoride or a control dentifrice containing sodium monofluorophosphate. Both groups followed the same described routine: applying dentifrice to two test teeth with a finger, brushing those test teeth, and then brushing the whole mouth. Participants brushed twice daily, in the morning and evening, for 3 days. This matched use procedure makes the dentifrice formulation the principal stated difference between the two arms; other details of treatment delivery are not reported in the registry record.

The primary endpoint was change from baseline in Schiff Sensitivity Score on Day 3. The registry defines the primary analysis population as ITT participants who were randomized, received treatment at least once, and contributed at least one post-baseline efficacy assessment. The primary outcome counts were 102.0 for the test arm and 100.0 for the control arm. The overall enrollment and outcome-specific counts are not identical descriptions of the same denominator: the registry gives enrollment as 205 and lists the ITT outcome counts separately. Further reasons for the difference are not reported in the registry record.

The registry also lists two secondary outcome topics: Schiff Sensitivity Score after a single direct application on Day 0, and tactile threshold on Day 0 and Day 3. Numerical results are posted for the Day 0 Schiff outcome. Numerical tactile-threshold results are not reported in the registry record. No detailed recruitment criteria, masking procedures, or original sample-size justification are reported in 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.

Before assignment: A total of 246 participants were screened, out of which 205 participants enrolled in the study. 41 of screened participants were not enrolled because of screening failure. Of 205 enrolled participants, 204 were randomized in study, one participant was not randomized due to lost to follow up.

Overall Study

Analysis population for the primary outcome, as defined in the registry: Intent to treat (ITT) population, defined as all participants who were randomized, received study treatment at least once \& provided at least one post-baseline (post treatment) assessment of efficacy. Number of participants analyzed is from ITT population evaluated at specific time points for each treatment arms respectively.

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 Change From Baseline in Schiff Sensitivity Score on Day 3, measured over Baseline, Day 3.

The primary endpoint is change from baseline in Schiff Sensitivity Score on Day 3. An examiner applies an evaporative air stimulus to each individual tooth and records the participant’s response on a scale from 0 to 3. A score of 0 means no response to air stimulation. A score of 1 means a response without a request to stop the stimulus. A score of 2 means a response with a request to stop or movement away from the stimulus. A score of 3 means the participant considers the stimulus painful and requests that it be stopped.

The endpoint is used to quantify sensitivity in a structured way: the examiner follows the same response categories, and change from baseline expresses how the score shifts from the pre-treatment assessment. The registry explicitly states that a reduction in Schiff score indicates improvement in sensitivity. The measure is therefore interpretable in terms of the direction of change, while the scale remains an examiner-recorded response to a particular stimulus rather than a direct measure of every aspect of daily experience.

The reported group means are changes from baseline, not Day 3 scores in isolation. The test group’s mean change was -1.37, and the control group’s was -0.45. The negative values indicate decreases from baseline; the larger decrease in the test group is consistent with the endpoint’s stated direction of improvement. Interpretation should remain tied to this scale, the treatment routine, and the short assessment period described in the registry record.

7. Results Posted in the Registry

• Test Dentifrice Containing Stannous Fluoride: mean -1.37 versus -0.45 on control; difference -0.92 (95% CI -1.05 to -0.79), standardized effect d = -1.90; z-test p = <0.001.

8. Secondary Efficacy Endpoints

The registry also posts results for secondary outcomes. For each outcome below, the endpoint type, the test applied to the posted summary statistics, the result and its interpretation are given in turn. Secondary endpoints are usually not adjusted for multiple testing, so they support rather than confirm the primary finding.

Change From Baseline (Day 0 Pre-treatment) in Schiff Sensitivity Score on Day 0 (After 60 Seconds of Single Direct Application)

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard deviations.
• Result:
  • Test Dentifrice Containing Stannous Fluoride: mean -0.63 versus -0.38 on control; difference -0.25 (95% CI -0.38 to -0.12), standardized effect d = -0.52; z-test p = <0.001.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the mean is statistically lower for Test Dentifrice Containing Stannous Fluoride than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

The secondary outcomes broaden the measurement beyond the primary Day 3 Schiff score. The registry lists a Day 0 Schiff assessment after a single direct application and tactile-threshold assessments on Day 0 and Day 3. The posted numerical secondary result is for the Day 0 Schiff change. Tactile-threshold results are not reported in the registry record, so a numerical pattern across all listed secondary measures cannot be assessed from the record.

The posted Day 0 Schiff comparison has the same direction as the primary result: the test group’s mean change is more negative than the control group’s. This provides a directionally similar observation for the early assessment, but it should not be treated as a separate confirmation of the primary result. It concerns another assessment time and is among multiple secondary outcomes. It also follows a single direct application, rather than the full 3-day brushing routine used before the primary endpoint.

Secondary results generally carry less weight than a prespecified primary analysis because there may be several opportunities to find an apparently notable result. If many outcomes or time points are examined, the chance of at least one result appearing unusual by chance can increase. The registry record does not report a multiplicity adjustment or a hierarchy for interpreting secondary tests. The posted secondary p-value is therefore best read as unadjusted evidence for that particular comparison, not as a multiplicity-controlled confirmation.

The secondary outcomes may help describe the pattern and timing of measured responses, but they do not replace the primary endpoint or resolve the limitations of its short follow-up. In particular, the absence of numerical tactile-threshold results in the registry record limits how comprehensively the trial’s secondary outcome pattern can be evaluated.

Secondary outcomes registered for this trial, for reference (only those above were recalculated):

• Change From Baseline (Day 0 Pre-treatment) in Schiff Sensitivity Score on Day 0 (After 60 Seconds of Single Direct Application)
• Change From Baseline (Day 0 Pre-treatment) in Tactile Threshold on Day 0 (After 60 Seconds of Single Direct Application) and Day 3

9. Statistical Interpretation

10. Statistical Methods Explained

The posted primary comparison is a difference between mean changes in a continuous outcome. A continuous measure can take a range of numerical values, and a group mean describes its average. Here, each participant’s outcome is change from baseline in Schiff Sensitivity Score, and the group means summarize those changes. Negative means indicate decreases from baseline. Since the registry states that a reduction in score indicates improvement in sensitivity, the sign of the mean difference has a direct interpretation for this endpoint.

What does the mean difference represent?

The recalculated mean difference is -0.92 for test dentifrice compared with control dentifrice. It compares the test-group mean change with the control-group mean change. A negative value means the test group had a more negative average change. This is not the same as a within-group test asking whether one arm changed from baseline, and it does not describe how many individuals had a change in a particular direction. A mean can summarize the group while concealing variation in individual responses.

The recalculation uses the posted arm summaries and is unadjusted. The registry separately reports an ANCOVA result, described as a least-squares mean difference. ANCOVA is a regression-based method that can compare groups while accounting for specified covariates, often including a baseline measure. The registry record names the method but does not report the covariates, model details, or assumptions used in that analysis. It is therefore possible to distinguish the reported adjusted analysis from the unadjusted recalculation, but not to reconstruct the sponsor’s full model from the record.

What does a standard deviation describe?

A standard deviation describes the spread of participant values around a group mean. It is not the uncertainty in the mean itself, and it is not a range that is expected to contain every participant’s value. The primary standard deviations were 0.52 in the test group and 0.443 in the control group. These describe variation in the observed changes within each arm. The group sizes and variability contribute to the precision of a mean comparison, but the standard deviations alone do not determine whether a difference is clinically important.

The recalculation uses the group counts and variation to estimate an unadjusted contrast and its uncertainty. A confidence interval expresses a range of values compatible with the data under the method’s assumptions. If such an interval excludes zero, that is consistent with evidence of a nonzero average difference under that analysis. The registry’s ANCOVA analysis likewise reports a 95% confidence interval that excludes zero. An interval does not give the probability that the true effect lies within its particular limits, and it does not incorporate uncertainty from limitations not represented by the statistical model.

How should the p-values be read?

A p-value describes how unusual data at least as incompatible with a specified null hypothesis would be under that hypothesis and the analysis assumptions. It is not the probability that the null hypothesis is true, nor does it measure the size or importance of the observed difference. The recalculated unadjusted result is reported as p <0.001, while the registry’s ANCOVA result is reported as p <.0001. Both are small p-values for the respective analyses. Their interpretation remains conditional on the analysis and on the assumptions used to obtain them.

The analyses concern a mean difference between randomized groups. They do not show that each participant experienced the average change, and they do not establish an individual response. The result is also specific to the endpoint as defined: change in examiner-assessed Schiff score after the stated treatment period. The registry does not report a prespecified threshold for interpreting the magnitude as clinically meaningful.

Why can over-dispersion matter in other settings?

General statistical explanation: in count outcomes, over-dispersion means that the observed variation exceeds what a simple model assumes. If a model underestimates variation, its standard errors can be too small and its confidence intervals too narrow. That issue is relevant to some count-data analyses, but the primary endpoint in this trial is a continuous score change, and the registry reports a mean-based outcome analysis. The record does not describe an over-dispersion assessment for this endpoint.

What distinguishes recalculation from the registry analysis?

The recalculated comparison is a simple unadjusted calculation from the posted summary statistics. The registry analysis is ANCOVA and reports a least-squares mean difference. Adjustment can change an estimate or its uncertainty, depending on the model and the data. Here, the two reported estimates are close, but the adjusted analysis cannot be reproduced in full from the registry record because the model specification is not reported. Neither analysis substitutes for the original trial protocol or a complete statistical analysis plan; those details are not reported in the registry record.

The sample-size illustrations use a normal approximation and planning assumptions stated in the registry materials. They are separate from the primary analysis and are not evidence about the trial’s original design rationale. A planned sample size concerns what might be needed to detect a specified effect under assumptions; it is not a result about the probability that the observed trial found a true effect. The trial’s original sample-size justification and design assumptions are not reported in the registry record.

11. Confidence Intervals and Precision

Precision concerns how much uncertainty surrounds an estimated effect. The recalculated primary mean difference is -0.92, based on 102.0 test participants and 100.0 control participants. The group standard deviations are 0.52 and 0.443. The recalculated confidence interval excludes zero, and the registry’s reported 95% ANCOVA confidence interval also excludes zero. Together with the reported p-values, this indicates that the estimated between-group difference is not close to zero under either stated analysis.

A confidence interval is a range produced by a statistical procedure that, under its assumptions and repeated use, has a stated coverage property. It conveys uncertainty around the estimate; it does not show the spread of individual participant outcomes. Nor does it mean that every value in the interval is equally plausible. The registry reports a 95% confidence interval for the ANCOVA least-squares mean difference, but its endpoint values have more than three decimal places. The precise bounds are therefore not repeated in this explanation. The important interpretive point is that the reported interval excludes zero.

Precision is conditional on the analysis, the observed participants, and the model assumptions. The recalculation is unadjusted, while the registry’s result is from ANCOVA. The registry record does not provide the model covariates or all details needed to assess the adjusted interval independently. The estimates are close, but that agreement does not remove the need to distinguish the analyses.

Statistical precision also does not establish clinical importance. The registry defines the direction of improvement but does not report a threshold for a meaningful change in Schiff score. The interval’s exclusion of zero supports a distinction from no average difference under the analysis; it does not, on its own, answer whether the magnitude matters to participants or whether the difference persists beyond Day 3.

12. Planning a Similar Trial: Sample Size

This is a planning illustration, not a re-evaluation of the original trial. It asks: if a new study wanted to detect a difference like the one observed, or a smaller one, how large would it need to be? It is deliberately not “observed power” of the finished trial, which is not a meaningful quantity.

The planning figures are participants per arm, not total events. The registry’s planning assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The effect to detect is specified as a fraction of the observed effect. These are planning illustrations based on the observed result, not the trial’s original design assumptions; the original sample-size justification is not reported in the registry record.

The 80% power column describes the number of participants per arm that the calculation estimates would be needed to have an 80% chance of detecting the specified effect under the stated assumptions, if that effect and those assumptions were correct. The 90% column expresses the analogous target with a higher chance of detection. For the primary outcome, planning for 100% of the observed effect gives 5 participants per arm for 80% power and 6 per arm for 90% power. Planning for 75% gives 8 and 11 participants per arm, respectively; planning for 50% gives 18 and 24.

The pattern is the key interpretation: when the effect to be detected is smaller, more participants are needed to distinguish it from random variation at the same nominal power and significance level. The planning figures are not observed power. They are illustrative calculations based on the observed effect, and they should not be read as a retrospective measure of how likely the completed study was to detect its result. The associated curve is best read as displaying this same relationship between effect size and planned participant numbers, rather than as a record of trial enrollment or observed outcomes.

13. How the Sample Size Is Derived

Power is the probability that a study of a given size rejects the null hypothesis when a specific true effect exists. It depends on four things: the effect to detect, the variability of the outcome, the significance level (here a two-sided α of 0.05, so z_1−α/2 = 1.960) and the desired power (z_1−β = 0.842 for 80% and 1.282 for 90%).

Formula

n is the number of participants in each arm, Δ is the difference in means to detect and σ is the common standard deviation.

Worked calculation for this trial

1. Observed difference Δ = -0.920; pooled standard deviation σ = 0.483.
2. n = 2 × (1.96 + 0.842)² × 0.483² / -0.920² = 4.3, rounded up to 5 participants per arm for 80% power.

The smaller-effect rows in the table above repeat the same calculation with the effect multiplied by 0.75 and 0.5 (for ratios, applied to the logarithm of the ratio).

R code

alpha <- 0.05
z_a   <- qnorm(1 - alpha / 2)          # two-sided
delta <- -0.92                      # observed difference in means
sigma <- 0.483420370898869                     # pooled standard deviation
n_per_arm <- function(power, frac = 1) {
  ceiling(round(2 * (z_a + qnorm(power))^2 * sigma^2 / (delta * frac)^2, 6))
}
for (f in c(1, 0.75, 0.5))
  cat(sprintf("%3.0f%% of observed effect: n per arm = %s (80%% power), %s (90%% power)\n", 100 * f,
              format(n_per_arm(0.80, f), big.mark = ","), format(n_per_arm(0.90, f), big.mark = ",")))

# Check against R's built-in function (t-based, so very slightly larger)
cat("power.t.test:", round(power.t.test(delta = delta, sd = sigma, power = 0.80)$n, 1), "\n")

# Simulation: exact two-sample t-test using simulated means and variances
set.seed(2924350)
n    <- n_per_arm(0.80)
reps <- 20000
m_diff <- rnorm(reps, delta, sigma * sqrt(2 / n))             # difference in sample means
s2     <- sigma^2 * rchisq(reps, 2 * (n - 1)) / (2 * (n - 1))   # pooled sample variance
tstat  <- m_diff / sqrt(s2 * 2 / n)
cat(sprintf("Simulated power at n = %s per arm: %.3f (%d replicates)\n", format(n, big.mark = ","), mean(abs(tstat) > qt(0.975, 2 * (n - 1))), reps))

Output from running the code

100% of observed effect: n per arm = 5 (80% power), 6 (90% power)
 75% of observed effect: n per arm = 8 (80% power), 11 (90% power)
 50% of observed effect: n per arm = 18 (80% power), 24 (90% power)
power.t.test: 5.5 
Simulated power at n = 5 per arm: 0.752 (20000 replicates)

The simulation draws many sets of group means and variances at the planned sample size and counts how often the two-sample t-test rejects the null. It should land close to the target power; at very small required sample sizes it can fall below it, because the normal approximation is rough there.

14. Analyses Reported by the Sponsor

The registry reports the sponsor’s primary analysis as an ANCOVA estimating a least-squares mean difference between the two groups. The reported difference is -0.924, with a 95% confidence interval that excludes zero and p <.0001. The direction indicates a greater decrease in Schiff score in the test group, consistent with the endpoint’s stated interpretation that lower scores indicate improvement.

The recalculated analysis uses the posted group means, standard deviations, and counts without covariate adjustment. It estimates a mean difference of -0.92, with an unadjusted p-value of <0.001. The two estimates are close and convey the same direction of group difference. They are not identical analyses: ANCOVA uses a model, while the recalculation is a simple comparison of the reported summaries.

The registry record does not give the ANCOVA covariates or sufficient model detail to reproduce the sponsor’s analysis. The recalculation therefore serves as a transparent check on the posted group summaries, not as a replacement for the sponsor’s model. The sponsor analysis and the recalculation are directionally consistent, and the registry does not flag a discrepancy between them.

15. Multiplicity, Missing Data and Analysis Populations

The registry identifies a primary endpoint and lists secondary outcomes, but it does not report a multiplicity strategy for controlling the chance of false-positive findings across multiple outcomes or assessment times. No adjustment method, testing sequence, or gatekeeping procedure is reported in the registry record. The primary result should therefore be distinguished from secondary comparisons, whose unadjusted results may be more vulnerable to chance findings when several analyses are considered together.

The primary population is described as ITT participants who were randomized, received study treatment at least once, and had at least one post-baseline efficacy assessment. Outcome counts are 102.0 for the test group and 100.0 for the control group. This definition does not include randomized participants without any post-baseline efficacy assessment. The registry record does not describe how those participants were handled, whether any additional missing observations occurred, or what method was used to address missing outcome data.

The registry lists enrollment as 205, while the primary analysis counts are reported by arm for the defined ITT population. The record does not give a participant flow accounting for the relationship between overall enrollment, randomization, treatment receipt, and outcome availability. It is therefore not possible to identify reasons for differences between these counts or to assess missingness patterns from the registry record.

The registry reports an ANCOVA for the primary outcome, but details of the model, including covariates and any diagnostics, are not reported. The registry also does not report the original statistical analysis plan, protocol-level sample-size justification, or interim analysis procedures. These absences limit assessment of whether all analyses followed a prespecified plan and how the reported analyses relate to all planned outcomes. They do not alter the values that are posted, but they constrain how fully the analysis process can be evaluated.

16. 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 0% reporting threshold.

Most frequent non-serious adverse event terms

The registry’s adverse-event summary lists 102 participants at risk in each group. It records zero serious adverse events in the stannous fluoride group and zero in the sodium monofluorophosphate group. It also records zero deaths in both groups. These are the serious-event and death counts in the posted summary; they do not establish that the risk of a rare event is zero.

The summary lists other adverse events affecting 9 participants in the test group and 11 in the control group. The registry record does not provide further detail about the nature, severity, timing, or relationship to treatment of those events in the information. No serious-event terms are listed among the top serious terms.

Safety counts should be interpreted in light of the short 3-day treatment routine and the number of participants listed at risk. They describe events captured and reported in this trial, not every possible event or risks under longer use. The record does not provide enough detail to compare event types or determine their causes, and these counts should not be treated as advice about product use.

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

The posted primary data show a larger average reduction in Schiff Sensitivity Score after 3 days in the stannous fluoride group than in the sodium monofluorophosphate group. The recalculated mean difference is -0.92, and the registry’s ANCOVA estimate is -0.924. Both analyses favor a greater decrease in the test group on this scale, where the registry defines a reduction as improvement in sensitivity. The reported statistical evidence is strong against a zero average difference under the stated analyses.

That finding is specific to the outcome and conditions studied. It concerns an examiner-recorded response to an evaporative air stimulus, assessed as change from baseline, following the described twice-daily brushing routine. It is not a direct measure of every aspect of dentinal hypersensitivity, and the registry does not state a threshold that would establish whether the size of the difference is clinically meaningful.

The result does not establish that every participant experienced a reduction, because group means do not describe each individual response. It also does not establish how long the measured difference lasts: the primary assessment is on Day 3, and longer-term results are not reported in the registry record. The trial’s single-center setting, specific dentifrices, and brief use period also limit what can be inferred about other populations, products, or patterns of use.

The findings are not a complete account of benefit and risk. The registry reports adverse-event counts, but the event detail is limited, and the listed secondary tactile-threshold results are not reported in the registry record. The statistical result describes a comparison in the posted trial data; it is not medical advice and does not by itself determine how an individual should choose or use a product.

18. Why This Trial Matters Statistically

This trial illustrates the distinction between a measured difference and its interpretation. The primary measure is a change score with a defined direction: lower Schiff Sensitivity Scores indicate improvement. That makes the sign of the between-group mean difference interpretable, while leaving the clinical importance of its magnitude as a separate question. The registry does not provide a threshold for a meaningful change, so statistical evidence and clinical relevance should not be conflated.

It also illustrates why naming the analysis matters. The registry reports an ANCOVA least-squares mean difference, while the recalculation uses unadjusted group summaries. Their estimates are close, which supports a coherent reading of the posted direction, but the methods answer the question with different modeling choices. Because the model details are not reported, readers cannot fully reproduce or evaluate the sponsor’s adjustment.

The sample-size illustrations show how planning depends on the effect one aims to detect. Smaller target effects require more participants under the stated assumptions. Those figures are not the trial’s original justification and are not observed power, which helps separate design planning from inference about completed results.

Finally, the record demonstrates the importance of considering analysis populations, missing-data reporting, and multiplicity. The ITT population has a stated definition, but participant flow and missing-data handling are not reported. Secondary outcomes are listed, yet a multiplicity plan is not reported, and tactile-threshold results are absent. These details affect how confidently the record can be assessed beyond its primary comparison.

19. 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 trial is described as single-center and evaluates a specific pair of dentifrices under a short, 3-day routine. Those features narrow the setting and duration represented by the primary result. The registry record does not report longer-term follow-up, so persistence of the Day 3 difference cannot be assessed.

The trial is described as single-masked, but the masked party and practical masking procedures are not reported in the registry record. Details of the randomization procedure and allocation concealment are also not reported. The record states that allocation was randomized, but does not provide enough operational detail to assess those procedures.

The primary outcome counts are 102.0 and 100.0, whereas overall enrollment is 205. The registry’s ITT definition excludes participants without a post-baseline efficacy assessment, and the record does not report a participant flow explanation or missing-data method. As a result, the handling and possible impact of missing outcome data cannot be evaluated from the registry record.

The endpoint is an examiner-recorded response to an air stimulus. The registry explains the score categories and the direction of improvement, but does not report a clinically meaningful change threshold. Consequently, statistical evidence for an average difference does not settle the practical importance of its size.

The registry lists tactile-threshold secondary outcomes but does not report their numerical results. It also does not report a multiplicity strategy, detailed ANCOVA covariates, the original sample-size justification, or interim analysis procedures. These omissions limit assessment of the full analysis plan and the breadth of the outcome evidence. The reported findings remain interpretable as the posted short-term Schiff score comparison, with those limits in view.

20. Related Tutorials

21. Related Statistical Calculators

22. Sources

• ClinicalTrials.gov: The Efficacy of an Occluding Dentifrice in Providing Relief From Dentinal Hypersensitivity (DH) — NCT02924350.
• Registry record last updated 2018-08-20; status last verified 2018-02.
• Results first posted 2018-08-20.
• 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.

23. Record Summary

NCT02924350 is a completed randomized, parallel-group, single-center, single-masked study of dentinal hypersensitivity. It compared a stannous fluoride test dentifrice with a sodium monofluorophosphate control dentifrice in a twice-daily brushing routine for 3 days. Enrollment was 205.

The primary outcome was change from baseline in Schiff Sensitivity Score on Day 3. The test group mean change was -1.37 and the control group mean change was -0.45. The recalculated unadjusted mean difference was -0.92; the registry reports an ANCOVA least-squares mean difference of -0.924, with p <.0001.

The registry lists secondary Schiff and tactile-threshold outcomes. Numerical results are posted for the Day 0 Schiff outcome; tactile-threshold results are not reported in the registry record. The adverse-event summary reports zero serious events and zero deaths in both groups. Further details about missing data, multiplicity, model specification, and the original sample-size justification are not reported in the registry record.