Theracal Pulpotomy in Primary Molars: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Theracal Pulpotomy in Primary Molars (NCT04397094), a randomized phase 4 study. The primary outcome is Clinical Examination.

2. Clinical Question

3. Trial Design

The registry describes a completed, randomized, double-masked, parallel-group phase 4 trial. The listed interventions were Theracal LC and Formocresol, used as medicaments in pulpotomy of primary molars. Registry enrollment is 60. The arm descriptions refer to thirty primary molars treated with each medicament; the record does not provide additional details about the relationship between the number of molars and the number of individual participants.

The clinical examination outcome was recorded at 12 months. The arm descriptions also state that teeth were followed clinically and radiographically for 12 months. Radiographic Examination is listed as a secondary outcome, but its numerical results are not reported in the registry record summarized for this analysis.

The registry lists a study start date of 2017-12-01 and a primary completion date of 2018-03-17, with status marked completed. The sponsor is Ain Shams University. These registration details describe the study record; they do not provide information about recruitment procedures, treatment allocation concealment, masking procedures, protocol deviations, or the conduct of follow-up. Those details are not reported in the registry record.

The randomized parallel-group structure is relevant because the posted comparison is between the clinical outcome counts in the two assigned groups. Randomization can support a causal comparison when implemented as intended, but the registry information available for this outcome does not describe the allocation process or provide details needed to assess implementation. The trial design alone therefore does not resolve uncertainties about the outcome definition, missing observations, or analysis population.

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

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 Clinical Examination, measured over 12 months.

The primary outcome is titled Clinical Examination and is described as the number of participants with tooth mobility, restoration loss, gingival swelling or fistula, or pain on percussion. It is a count of participants with an event, rather than a continuous measurement. The stated assessment timeframe is 12 months.

In general, a clinical endpoint uses observable findings or reported symptoms to represent a health-related outcome. Counting participants with an event can make the result directly interpretable as the frequency of the recorded outcome in each group. However, this registry description does not explain whether any listed finding was sufficient to count as an event, whether all findings were assessed using prespecified criteria, or how assessments were handled if more than one finding occurred. The operational rule for combining the signs and symptoms is not reported in the registry record.

The registry reports 30 participants with the outcome in the Theracal LC arm and 30 in the Formocresol arm. The arm sizes are also listed as 30. The record therefore reports the outcome count as 30 in each arm, but it does not provide individual-level observations or further details about how the counts were established.

7. Results Posted in the Registry

• Formocresol: 100.0% (30/30) versus 100.0% (30/30) on control; risk difference 0.0 percentage points (95% CI 0.0 to 0.0), risk ratio 1.00 (1.00–1.00); unadjusted two-proportion z-test p = n/a.

8. Statistical Interpretation

9. Statistical Methods Explained

The primary result is a binary-outcome comparison summarized using counts and a risk difference. A binary outcome records whether each participant did or did not meet an outcome definition. In general, the risk in an arm is the proportion of participants meeting that definition, and the risk difference compares those proportions by subtraction. The registry labels the comparison as Formocresol versus Theracal LC. It reports a risk difference of 0.0, a confidence interval from 0.0 to 0.0, and p = 1.0.

The arm counts are 30 in each group, and the outcome count is also 30 in each group. These are the posted summary values. The outcome description refers to participants with specified clinical findings, but does not state the rule for classifying a participant as having the outcome. As a result, the numerical comparison can be described, while the clinical meaning of the combined count remains dependent on a definition that is not fully detailed in the registry record.

In general, a confidence interval represents a set of effect values compatible with the observed data and a chosen statistical procedure. Its width reflects statistical precision under that procedure and its assumptions. The registry interval has identical lower and upper limits, both 0.0. The method used to calculate it is not reported in the registry record. The posted interval should therefore not be treated as a newly calculated result or as evidence that every source of uncertainty is absent. It does not by itself address outcome misclassification, missing observations, or uncertainty about how the endpoint was defined.

In general, a p-value describes how unusual data at least as discrepant as those observed would be under a specified null hypothesis and statistical model. It is not the probability that the null hypothesis is true, and it does not measure the size or clinical importance of an effect. The registry reports p = 1.0 for the comparison. The statistical test and its assumptions are not reported in the registry record, so the value can be cited but its calculation cannot be independently assessed from these summaries.

General statistical interpretation of a binary comparison depends on the number of outcome events and the number of participants assessed in each arm. When the observed counts lie at a boundary, such as all assessed participants meeting the recorded outcome definition, some statistical procedures can behave differently from procedures used for outcomes with both event and non-event observations. This is a general consideration, not a claim about the calculation method used in this trial. The registry reports the counts but does not state whether all randomized participants were assessed, whether any observations were missing, or whether the posted interval and p-value came from a particular exact, approximate, or model-based procedure.

Randomization is intended to make assigned groups comparable on average, including for factors not measured at baseline. In general, the value of a randomized comparison depends on carrying out allocation as planned and preserving group assignment in the analysis. The record marks the trial randomized and double masked, but details of sequence generation, allocation concealment, masking procedures, deviations, and the analysis population are not reported in the registry record. Those omissions limit assessment of the protections against bias in this specific comparison.

The record lists two outcome measures and one posted secondary outcome, Radiographic Examination. It reports no analyses in the summary. Numerical findings, definitions, and analysis details for the radiographic outcome are not reported in the registry record. In general, when several outcomes or multiple analyses are considered, multiplicity can affect how often an apparently notable result occurs by chance. No multiplicity adjustment or prespecified hierarchy is described in the record, so whether and how multiplicity was addressed is not reported.

The registry also states assumptions for planning illustrations: a two-sided significance level of 0.05, equal allocation between the arms, and a normal approximation, with the effect to detect described as a fraction of the observed effect. Such calculations are planning illustrations, not observed power and not evidence about what the completed trial was designed to detect. The record does not report the trial's own sample-size justification or statistical plan. No planning values need to be interpreted as trial results.

10. Confidence Intervals and Precision

The posted estimate for the risk difference between Formocresol and Theracal LC is 0.0. Its confidence interval runs from 0.0 to 0.0, and the reported p-value is 1.0. These values express the comparison as recorded for the Clinical Examination endpoint at 12 months. The result is a point estimate with no interval width in the posted summary.

In general, a confidence interval is used to show the range of effect values compatible with data under a specified method. A narrower interval is commonly described as more statistically precise than a wider interval, but precision is conditional on the method and the data used. The registry record does not identify the interval procedure or provide participant-level data, so it is not possible to assess from this summary why the interval has identical limits or whether it reflects a particular calculation convention. The interval should be reported as posted, not treated as an independently verified estimate.

The endpoint count is 30 in each arm, and each arm is listed with a size of 30. The registry does not clarify whether all enrolled participants contributed to the primary outcome analysis, or describe missing observations or exclusions. Equal posted counts and a zero risk difference do not establish that the true underlying effects are exactly equal. Nor does the zero-width interval settle uncertainty from measurement, endpoint definition, or trial conduct.

Precision is also distinct from clinical importance. The registry does not give a threshold for a clinically important difference or an equivalence margin. Therefore, the result cannot be interpreted as demonstrating equivalence or non-inferiority. Its scope is the reported estimate and interval for this recorded outcome, under an analysis method that is not described in the registry record.

11. Multiplicity, Missing Data and Analysis Populations

The registry lists the Clinical Examination as the primary outcome and Radiographic Examination as a secondary outcome. It reports two outcome measures and one posted secondary outcome. The numerical results and detailed definition for the radiographic measure are not reported in the registry record. The record reports no analyses in the summary, and it does not describe a prespecified hierarchy among outcomes, a multiplicity adjustment, or an analysis plan for multiple comparisons.

In general, multiplicity matters when researchers evaluate several outcomes, time points, subgroups, or statistical contrasts. Conducting multiple tests can increase the chance of obtaining an apparently unusual result even when there is no underlying effect. Whether that issue applies, and how it was handled, cannot be determined from the registry entries available for this analysis. The presence of a listed secondary outcome does not establish that multiple testing occurred, and the absence of reported analyses does not show that it did not.

The record does not report missing-data counts, reasons for missingness, imputation methods, or the number of participants included in the endpoint analysis. It also does not identify whether the primary analysis followed an intention-to-treat, per-protocol, or other analysis population. Consequently, the posted counts cannot be used to determine how incomplete follow-up or exclusions may have affected the comparison.

These gaps are important for interpreting the result. The registry records 30 participants with the clinical outcome in each arm, but does not document whether outcome status was available for every assigned participant or how any unavailable assessments were treated. No assumptions about missingness or analysis populations can be made from the posted summary alone.

12. 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 lists zero serious adverse events among the 30 participants at risk in the Theracal LC group and zero among the 30 participants at risk in the Formocresol group. It reports zero deaths in both groups. For other adverse events, the posted counts are 3 in the Theracal LC group and 5 in the Formocresol group, with 30 at risk in each group.

These figures should be read as registry counts, not as proof that serious harms cannot occur or as a complete characterization of safety. The record does not describe the definitions used for serious and other adverse events, the methods for collecting them, the observation period specific to adverse events, or whether every participant was assessed in the same way. It also does not report event types for the other adverse events in the summary. No causal attribution can be inferred from the counts alone.

In general, zero recorded serious events means that none were reported in the listed group during the recorded observation, not that the underlying risk is zero. The posted adverse-event figures are separate from the primary clinical examination endpoint and should not be combined with it. They provide limited descriptive safety information for the registry record, with important details about ascertainment and classification not reported.

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

The registry result says that the clinical examination outcome count at 12 months was 30 in each arm, with an arm size of 30 in each group. The posted comparison gives a risk difference of 0.0, a confidence interval from 0.0 to 0.0, and p = 1.0. In plain statistical terms, the summary reports no observed difference in the count for this endpoint between the Theracal LC and Formocresol groups.

This result does not establish that the treatments are equivalent. Equivalence requires a prespecified margin defining what differences would be considered sufficiently small, together with an analysis designed to assess that question. No equivalence margin is reported in the registry record. The result also does not show that the underlying effects are exactly the same: the endpoint definition, statistical method, missing-data handling, and analysis population are not adequately described in the posted summary.

The endpoint is described as participants with tooth mobility, restoration loss, gingival swelling or fistula, or pain on percussion. The registry does not explain the rule used to combine these findings. It does not give component-specific counts, so the equal totals cannot establish that each listed sign or symptom occurred equally often. Nor do the primary outcome counts address the radiographic secondary outcome, whose numerical results are not reported in the registry record.

The safety counts are also limited. No serious adverse events or deaths are reported in either group, while the record lists other adverse-event counts of 3 and 5. These counts do not determine whether an event was caused by a treatment or describe all possible harms.

The defensible conclusion is therefore specific: the posted summary reports equal counts for the defined clinical examination outcome at the stated follow-up. Broader conclusions about comparative benefit, equivalence, other clinical or radiographic outcomes, or safety are not established by these registry results.

14. Why This Trial Matters Statistically

This trial is statistically informative because its posted primary comparison is an example of how a simple numerical equality can still require careful interpretation. The outcome count is 30 in each group, and the reported risk difference is 0.0. Yet understanding what that equality represents depends on how the clinical findings were combined, which participants were assessed, and which statistical procedure produced the confidence interval and p-value. Those details are not reported in the registry record.

For biostatisticians and clinical researchers, the case highlights the importance of a precise endpoint definition. A composite description that lists several findings may summarize clinically relevant events, but interpretation depends on an explicit rule for classifying participants. Component-level counts can also be useful because a common total can conceal differing patterns among the component findings. The registry does not report those details.

The posted zero-width confidence interval illustrates why numerical output should be read alongside methods and data provenance. A confidence interval ordinarily communicates uncertainty under a specified procedure; when its limits coincide, readers need to know the calculation method and analysis dataset before treating that output as a complete account of precision. The registry summary does not supply that methodological context.

The record also illustrates the distinction between a nonsignificant or null-looking comparison and a formal demonstration of equivalence. The reported p-value and point estimate alone do not answer whether differences within a clinically acceptable range have been ruled out. That requires a stated margin and an analysis tailored to the question.

Finally, registered secondary outcomes, safety counts, and missing-data details matter to a full interpretation. The radiographic measure is listed without numerical results, and the analysis population and missingness are not described. These limitations make the result a useful case study in separating what the posted statistics state from what the registry record leaves unresolved.

15. 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 primary outcome description lists several clinical signs and symptoms but does not specify how they were combined into a participant-level event. It is therefore unclear from the registry record whether a participant was counted after any one finding, whether another rule was used, or how conflicting or repeated assessments were handled. Component-specific event counts are not reported.

The registry lists an arm size of 30 and an outcome count of 30 in each group, but does not report whether outcome data were available for every participant assigned to each arm. Missing-data counts, exclusions, protocol deviations, and the primary analysis population are not reported. These omissions prevent assessment of whether the posted counts include all randomized participants.

Although the design is marked randomized and double masked, procedural details about sequence generation, allocation concealment, and implementation of masking are not reported in the registry record. The statistical analysis method for the risk difference, confidence interval, and p-value is also not reported. The interval has identical limits, but the summary does not explain the calculation behind that result.

Radiographic Examination is listed as a secondary outcome, without numerical results in this summary. The record does not describe multiplicity procedures or provide a detailed statistical analysis plan. It also does not report an equivalence margin, so the equal observed counts cannot be interpreted as evidence of equivalence.

The adverse-event summary gives counts but not event definitions, collection procedures, or detailed event types. Together, these limitations restrict interpretation to the posted clinical outcome counts and the descriptive safety figures. They do not permit a full assessment of trial conduct, outcome ascertainment, or the robustness of the statistical analysis.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Theracal Pulpotomy in Primary Molars — NCT04397094.
• Registry record last updated 2020-07-29; status last verified 2020-07.
• Results first posted 2020-07-29.
• 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.

19. Record Summary

The registry describes a completed, randomized, double-masked, parallel-group phase 4 trial comparing Theracal LC with Formocresol for pulpotomy in primary molars. Enrollment is listed as 60. The arm descriptions refer to thirty primary molars in each group, with clinical and radiographic follow-up for 12 months.

For the primary Clinical Examination outcome at 12 months, the registry reports 30 participants with the outcome in each arm, with each arm listed at 30. The posted risk difference for Formocresol versus Theracal LC is 0.0, with a confidence interval from 0.0 to 0.0 and p = 1.0. The outcome definition lists tooth mobility, restoration loss, gingival swelling or fistula, and pain on percussion, but does not explain how these findings were combined.

The registry lists Radiographic Examination as a secondary outcome, without numerical results in the record. It reports zero serious adverse events and deaths in both groups, and other adverse-event counts of 3 for Theracal LC and 5 for Formocresol. Details about missing data, analysis populations, outcome procedures, and the statistical plan are not reported in the registry record.