Comparison of Mineral Trioxide Aggregate (MTA) & Ferric Sulfate (FS) Pulpotomies: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Comparison of Mineral Trioxide Aggregate (MTA) & Ferric Sulfate (FS) Pulpotomies (NCT02783911), a randomized na study. The primary outcome is Comparison of the Clinical Success Between Mineral Trioxide Aggregate (MTA) & Ferric Sulfate (FS) Pulpotomies in Primary Molars.

2. Clinical Question

This is a comparison of two materials used in pulpotomy, not a comparison of pulpotomy with no treatment. The registry identifies the study as randomized, triple-masked and parallel. It does not describe which people or roles were masked, so the masking label alone does not establish who was unaware of treatment assignment.

The registry reports enrollment of 57, but it does not provide a primary-outcome result or the numbers evaluated in each arm at each visit. It therefore does not establish from the posted primary outcome information whether the observed clinical or radiographic assessments favored either material. The safety counts are reported separately and should not be treated as a substitute for the primary comparison.

3. Trial Design

The registry describes a randomized, triple-masked, parallel-group study comparing MTA with FS pulpotomies for primary molars. Random allocation is intended, as a general design principle, to balance prognostic factors between groups on average. It does not guarantee balance in a particular trial, especially when the numbers are limited. The record does not describe the allocation sequence, concealment procedures or the people covered by triple masking.

The listed enrollment is 57. The record gives a start date of 2015-01-29 and a primary completion date of 2017-03-14, and lists the study status as terminated. It does not report why the trial was terminated, when that decision was made, or whether termination affected recruitment, follow-up or analysis. Those details should not be inferred from the status alone.

Participants were assigned to an MTA or FS arm. The registry describes MTA paste as being placed once on the pulp orifice, while FS paste was placed there for 15 seconds and removed. Both descriptions specify an amount of less than 1 gram. The record does not describe additional treatment procedures, deviations from these descriptions, or adherence to the assigned treatment.

The outcome description plans clinical examinations at recall visits and periapical radiographs assessed for pathologies. Recall appointments are listed at 6 months, 9 months and 12 months, with a primary timeframe of 1 year. The description says participating faculty members calibrated to clinical criteria would conduct blinded clinical examinations. Radiographs were to be evaluated by two pediatric dentists and one endodontist. These are descriptions of the registry’s stated assessment approach; the record does not establish which procedures were completed for every participant.

The registry lists Loma Linda University as sponsor. It does not report the reason for choosing the enrollment target, an intended allocation ratio, or whether recruitment and follow-up proceeded as planned. The meaning and consequences of the terminated status are therefore not clear from the registry record alone.

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: 3-10 years old, deep caries, No radiographic signs of internal/external root resorption, No pathology change, no swelling or abscess.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: The patients who came back for follow up for long term clinical and radiographic success.

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.

Population: some participants has more than one tooth needs pulpotomy treatment

6. Primary Endpoint

The registry lists the primary outcome as Comparison of the Clinical Success Between Mineral Trioxide Aggregate (MTA) & Ferric Sulfate (FS) Pulpotomies in Primary Molars, measured over 1 year.

The primary outcome is titled as a comparison of clinical success between MTA and FS pulpotomies in primary molars. Its unit is the tooth, and the measure is described as a count of units. The timeframe is 1 year. The population description refers to patients who returned for follow-up for long-term clinical and radiographic success.

The registry describes clinical examination at recall visits and radiographic review for the presence of various pathologies. It says the assessments were to be scored using criteria established by Zurn and Seale 2008. Clinical examinations were described as blinded, and the radiographs were to be evaluated by two pediatric dentists and one endodontist. The description also refers to measuring intra-rater and inter-rater agreement for radiographic assessment.

In general, a clinical endpoint aims to capture findings relevant to the condition being assessed, while radiographs can contribute information about pathologies that may not be evident from clinical examination alone. For this study, the registry’s description combines clinical and radiographic assessment, but it does not fully specify how the findings were combined into a single success definition or how each category was counted. It also does not report the observed counts of teeth meeting the criteria or a between-arm estimate. Thus, the endpoint’s planned assessment is described, but its comparative result is not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a randomized, parallel-group comparison and lists triple masking. These features address different aspects of study design. As a general statistical principle, randomization assigns treatment by chance, helping limit systematic differences between treatment groups at the start of a study. Parallel-group designs compare groups followed under separate assigned treatments. Masking can reduce the influence of knowledge about treatment assignment on care, assessment or reporting, but the registry does not identify which roles were masked or how masking was maintained.

What does the outcome assessment involve?

The stated assessment includes clinical examinations and periapical radiographs at recall visits. Participating faculty members were described as calibrated to clinical scoring criteria and blinded during clinical examination. Radiographs were to be evaluated for the presence of various pathologies by two pediatric dentists and one endodontist. Scores were to be based on criteria established by Zurn and Seale 2008 and transferred to Microsoft Excel. The description does not report the actual scoring categories, the operational definition of success, or the completed assessments for each visit.

The registry names three tests: Mann-Whitney U, chi-square and Fisher’s exact. In general, the Mann-Whitney U test is a rank-based method for comparing two groups when observations can be ordered. It does not require the data to follow a normal distribution, but its interpretation depends on the outcome’s scale and on the characteristics of the group distributions. The record does not state which outcome was analyzed with this test or provide its result.

In general, a chi-square test assesses whether categorical outcomes and group membership are associated. It relies on assumptions about the expected counts in the categories. Fisher’s exact test is another method for categorical comparisons, often considered when counts are sparse. The registry names both tests but does not say which comparisons used each one, whether assumptions were assessed, or whether an alternative analysis was used. The tests’ names alone do not disclose the results or the precision of a comparison.

What does the agreement assessment tell readers?

The description says Cohen’s kappa would be used to measure intra-rater and inter-rater agreement for radiographic assessment. In general, kappa summarizes agreement between ratings while accounting for the agreement expected by chance under its assumptions. Intra-rater agreement concerns consistency when the same assessor rates material more than once; inter-rater agreement concerns consistency between assessors. Kappa does not by itself establish that ratings are accurate, and interpretation depends on the rating categories and the pattern of judgments. No kappa estimate, uncertainty interval or assessor-specific result is reported in the registry record.

Because there are assessments at 6 months, 9 months and 12 months and the description mentions multiple tests and radiographic pathologies, the analysis could involve more than one contrast or outcome. In general, testing multiple hypotheses can increase the chance of finding at least one apparently unusual result by chance if no adjustment or prespecified hierarchy is used. The registry record does not report whether multiplicity was addressed, which comparisons were considered primary, or whether one time point was prioritized in analysis.

What cannot be inferred from the stated methods?

A methods description is not the same as a complete statistical analysis plan or a report of completed analyses. The registry does not report a model specification, covariate adjustment, a primary effect measure, a confidence interval method, or detailed rules for handling repeated observations from a tooth or participant. The unit is listed as the tooth, but the record does not explain whether multiple teeth from one participant were possible or, if so, how within-participant dependence was addressed. Such dependence can matter because observations from the same person may be correlated; this is a general statistical consideration, not a claim that it occurred in this study.

The record also does not report how missing clinical examinations or radiographs were handled, whether the analysis followed assigned treatment, or whether a per-protocol analysis was planned. In general, missing follow-up can affect the interpretation of a comparison if the people assessed differ systematically from those not assessed. Since the primary population description refers to patients returning for follow-up, the number and characteristics of those not returning would be relevant, but they are not reported.

The study status is listed as terminated, yet the analysis plan, timing and reason for termination are not reported. The registry does not provide enough detail to determine whether the named tests were completed exactly as described or whether any changes occurred. No primary outcome result is posted, so there is no basis for evaluating a test statistic, p-value, estimated difference or interval. General explanations of these statistical methods clarify what the named methods are designed to do; they do not fill in the absent analysis results.

10. Multiplicity, Missing Data and Analysis Populations

The outcome description includes recall assessments at 6 months, 9 months and 12 months and clinical and radiographic findings. It also names Mann-Whitney U, chi-square and Fisher’s exact tests. This creates the possibility of multiple time-point, category or test comparisons. In general, when many hypotheses are tested, the chance of at least one chance finding can increase. The registry does not report whether a multiplicity adjustment, testing hierarchy or prespecified selection of a single comparison was used. Nor does it identify which comparison was treated as the primary statistical contrast.

The population description refers to patients who returned for follow-up. The record does not report how many returned at each recall, whether every assessed participant had radiographs, or how missing visits and incomplete assessments were handled. It does not report imputation, exclusion rules or sensitivity analyses for missing data. In general, an analysis restricted to observed follow-up can be difficult to interpret if return for assessment is related to treatment or outcome, but the registry does not provide information to evaluate that possibility in this study.

The registry does not identify an intention-to-treat, per-protocol or other analysis population for the primary endpoint. Although randomization is listed, the record does not say whether participants were analyzed according to assigned group or according to treatment received. It also does not explain how tooth-level outcomes were linked to participants if a participant contributed more than one tooth. These details are not reported in the registry record, so the analysis population and handling of any dependence among observations remain unclear.

Sample-size justification and the statistical plan are not reported in the registry record. The termination status is listed, but the record does not explain its timing or relationship to recruitment, follow-up or analysis. Without the planned comparison, missing-data rules and primary-outcome results, readers cannot determine whether the reported methods account for all planned outcomes and visits.

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 0% reporting threshold.

The registry reports zero serious adverse events in the MTA group, with 11 listed at risk, and zero in the FS group, with 46 listed at risk. For other adverse events, it likewise reports zero in the MTA group among 11 at risk and zero in the FS group among 46 at risk. No deaths are listed in either group.

These are the safety counts recorded for the two groups, not estimates of comparative clinical success. A zero count means that no event in the stated category is recorded for the listed group in this registry entry; it does not establish that the underlying event risk is absent. In general, the uncertainty around an event rate depends on the amount and completeness of observation, and a zero observed count can still be compatible with some underlying risk.

The registry does not report adverse-event definitions, collection procedures, duration of safety follow-up or whether events were judged related to treatment. It also does not explain how the safety populations were determined. The listed at-risk counts should therefore be read as the denominators recorded for these safety summaries, not assumed to be the number analyzed for the primary endpoint. The safety information is limited to the posted counts and should not be extended to conclusions about comparative safety beyond those observations.

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

The record establishes that a randomized, triple-masked, parallel comparison of MTA and FS pulpotomies was registered, with clinical and radiographic assessment planned over 1 year. It describes recall visits at 6 months, 9 months and 12 months and specifies the tooth as the outcome unit. It also records zero serious adverse events, zero other adverse events and zero deaths in each listed group. These are descriptive features of the registry entry.

The record does not report the primary clinical-success counts, a between-arm estimate, a confidence interval or a test result. Consequently, it does not show whether clinical success differed between the materials, the direction of any observed difference, or how precise a comparison might be. No conclusion about one material’s comparative performance follows from the study design description alone. The safety counts do not answer the primary efficacy question.

In general, an estimate describes the observed magnitude and direction of a difference, while a confidence interval conveys the range of values compatible with the data under the analysis assumptions. A p-value, when reported, addresses a particular null hypothesis under a specified method; it does not quantify clinical importance or establish that an effect is absent. None of these primary comparison results is reported in the registry record, so these concepts cannot be applied to a study-specific estimate.

The enrollment figure of 57 does not by itself reveal the number with complete follow-up or the amount of outcome information available. The follow-up population is described as people who returned, but visit-specific return counts and missing-data handling are not reported. The terminated status is also not explained. Those unknowns limit assessment of completeness and potential bias, without establishing that the analysis was biased.

The most defensible interpretation is therefore narrow: the registry describes the intended comparison, assessments and named statistical tests, and provides limited safety counts, but it does not report the primary comparative result. The evidence in the record is insufficient to characterize the observed clinical-success difference or its precision.

13. Why This Trial Matters Statistically

This trial raises statistical questions that are important in small clinical comparisons. Randomization can support a fair comparison in principle, but interpretation still depends on how many participants and teeth were assessed, how complete follow-up was, and whether the analysis preserved the assigned groups. The registry reports enrollment of 57 but does not report the primary outcome counts or the number assessed at each recall. Thus the amount of information behind the clinical comparison cannot be evaluated from the posted primary results.

The outcome is described across multiple recall visits and includes clinical as well as radiographic assessment. General statistical practice requires clarity about which time point and outcome define the primary contrast, how repeated observations are handled and whether multiple comparisons are controlled or prioritized. These details help readers distinguish a planned primary question from exploratory comparisons. They are not reported in the registry record, despite the description naming several visits and tests.

The record also connects outcome assessment with rater agreement. In general, reliability matters because inconsistent classification can obscure or distort group comparisons. Naming Cohen’s kappa indicates an intended way to assess agreement, but without the kappa results, the rating categories and their definitions, readers cannot judge how reproducible the radiographic scoring was.

Finally, the registry’s terminated status and the absence of primary outcome results underscore why registration details and posted results serve different purposes. Design information can clarify what investigators intended to compare, but it cannot replace outcome estimates and uncertainty measures. The available entry is useful for identifying the study question and the methods described, while leaving the central comparative result unresolved.

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.

Several trial-specific limitations of interpretation arise from the registry record. The primary outcome is titled as clinical success, while its description covers both clinical examinations and radiographic pathology assessment. The record does not specify the complete success definition, explain how clinical and radiographic findings were combined, or provide the outcome categories and their observed counts. This makes the intended endpoint less reproducible from the description alone.

The endpoint population is described as patients who returned for follow-up, but visit-specific attendance and the number of teeth assessed are not reported. The record gives no missing-data procedures or analysis-population definition. It is therefore not possible to assess whether the primary comparison included all randomized participants, only those with observed follow-up, or another group. The unit is listed as the tooth, but handling of possible multiple teeth per participant is not described.

The registry names statistical tests without mapping each test to a specific comparison or reporting test statistics, estimates or uncertainty. It does not report the planned approach to multiple visits and outcomes, covariate adjustment, or a sample-size justification. No information is given about protocol deviations, treatment adherence or changes in the analysis plan.

The study is listed as terminated, but the reason and timing are not reported. The status alone does not indicate whether termination was related to recruitment, follow-up, safety or another matter. The enrollment figure does not resolve those questions and should not be interpreted as the number contributing primary endpoint data.

Finally, the safety summary reports no events in the listed categories, but definitions and collection details are absent. These gaps limit conclusions about both the primary comparison and the context of safety observation. They are limits of what the registry record reports, not evidence that particular procedures were or were not followed.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Comparison of Mineral Trioxide Aggregate (MTA) & Ferric Sulfate (FS) Pulpotomies — NCT02783911.
• Registry record last updated 2021-06-11; status last verified 2021-05.
• Results first posted 2021-06-11.
• 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

The registry record describes a randomized, triple-masked, parallel study comparing MTA and FS pulpotomies for primary molars. Loma Linda University is listed as sponsor, enrollment is 57, the start date is 2015-01-29, the primary completion date is 2017-03-14, and the status is terminated.

The primary outcome is a tooth-level count related to clinical success, with a timeframe of 1 year. The description includes clinical examination and radiographic assessment at recall visits at 6 months, 9 months and 12 months. Mann-Whitney U, chi-square, Fisher’s exact and Cohen’s kappa tests are named in the assessment description.

The registry does not report the primary comparative result, the reason for termination, missing-data procedures, or the analysis population. It reports zero serious adverse events, zero other adverse events and zero deaths in each listed group. These details describe the record but do not establish a comparative clinical-success result.