Evaluation of Self-adhesive Hybrid Resin Composite Compared to a Traditional Composite Resin in Restorations of NCCLs: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Evaluation of Self-adhesive Hybrid Resin Composite Compared to a Traditional Composite Resin in Restorations of NCCLs (NCT05751382), a randomized na study. The primary outcome is Assessment of Restorative Quality.

2. Clinical Question

The clinical question was whether restorations made with a self-adhesive hybrid resin composite, Surefil one, would differ in restorative quality from restorations made with the traditional composite resin Venus Pearl in non-carious cervical lesions (NCCLs). The planned assessment was at 36 months, using the World Dental Federation (FDI) criteria. The record also lists restorative quality, aesthetics, and pain among the secondary outcome topics.

The design description says that each participant was randomly assigned to receive the two restorations in different upper quadrants, with the Surefil one restoration placed on either the left or right side. This split-mouth arrangement makes within-participant comparison central to the intended question. The registry also labels the study model “parallel”; how that label relates to the split-mouth description is not explained in the record.

3. Trial Design

The registry describes a randomized, single-masked clinical investigation with a split-mouth design. Participants were assigned to receive Surefil one in either the left or right upper quadrant, while the other material was used in the other quadrant. This design is intended to compare materials within the same participant, rather than treating the two materials solely as separate groups of unrelated participants. The record does not say who was masked, how the randomization sequence was generated, or how allocation was concealed.

The registry lists enrollment of 16 and identifies Dentsply Sirona Implants and Consumables as the sponsor. The study start date is 2022-09-21, and the primary completion date is 2024-01-22. Its status is terminated. The brief summary describes a planned 3-year follow-up, while the primary outcome timeframe is stated as 36 months. The record does not explain the reason for termination or give a completed follow-up duration for participants.

The intervention descriptions distinguish the restorative procedures: Surefil one was applied according to the manufacturer's instructions and cured for 20 seconds with an LED lamp. For Venus Pearl, the description specifies application of iBond universal adhesive, layering the composite, and curing for 20 seconds. Further procedural details, including any deviations from these descriptions, are not reported in the registry record.

The registry lists seven outcome measures, including assessment of restorative quality, aesthetics, and pain, but the primary outcome population is explicitly described as premature termination of the study. No outcome analyses are listed. The record's “parallel” model label does not match the split-mouth allocation description at face value; clarification of the model label is not reported in the registry record. The planned structure is therefore best understood from the detailed arm descriptions, while recognizing that the record does not fully resolve the discrepancy in its design labels.

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

Analysis population for the primary outcome, as defined in the registry: Premature termination of 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 Assessment of Restorative Quality, measured over At 36 months follow-up..

The primary endpoint is titled “Assessment of Restorative Quality.” The record states that restorations would be evaluated using the World Dental Federation (FDI) criteria at 36 months. These criteria provide a structured way to assess how a restoration performs clinically across defined aspects of quality, rather than relying only on an informal overall impression. In general, a standardized assessment can support consistent evaluation across materials and participants, although its value depends on clear scoring procedures and complete follow-up.

The endpoint is relevant to the trial question because the comparison concerns two materials used for direct restorations. A 36-month assessment was intended to describe the restorations’ clinical performance over the planned follow-up period. The registry does not provide the particular FDI categories, the scoring rules, assessor training procedures, or the way scores would be combined or compared. Those details are not reported in the registry record.

Most importantly, the record does not provide primary endpoint results. It identifies the primary outcome population as “Premature termination of study,” and no analyses are listed. There are therefore no reported FDI scores, category counts, treatment contrasts, or uncertainty estimates on which to base an estimate of comparative restorative quality. The endpoint definition describes what was planned for assessment; it is not evidence that the assessment was completed or that a comparative result was established.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Several design and analysis ideas help explain what would be needed to interpret a comparison of this kind. These are general statistical explanations; the registry record does not report that these methods were used.

Why the split-mouth structure matters

In a split-mouth study, each participant receives both interventions in different locations. This creates paired observations: the two restorations from one participant may share characteristics that make them more alike than restorations from different participants. A paired analysis uses that within-participant link when estimating a comparison. In general, accounting for pairing can improve precision when within-participant outcomes are correlated. Treating all restorations as if they came from unrelated people can misstate the uncertainty.

The registry describes assignment of Surefil one to either the left or right upper quadrant and describes the other material in the other quadrant. It does not report the precise unit of randomization, the sequence-generation procedure, the allocation-concealment method, or the analysis unit. The model field labels the study “parallel,” even though the detailed descriptions specify split-mouth treatment. Since the record does not explain this difference, the exact analysis structure cannot be confirmed from the registry alone.

What an endpoint estimate would mean

An endpoint estimate would describe the observed difference or relationship between the materials for the specified restorative-quality measure. A confidence interval, in general, expresses the range of values compatible with the data under the assumptions of the analysis. Its width reflects statistical precision: a broad interval indicates that the data leave greater uncertainty about the size or direction of a comparison, while a narrower interval indicates greater precision. Neither an estimate nor its interval establishes clinical importance by itself.

No primary outcome estimate or confidence interval is reported in this registry record. The endpoint description says that FDI criteria were planned for assessment at 36 months, but it does not give the scores, categories, or an analysis comparing the materials. As a result, readers cannot evaluate the size, precision, or direction of a primary comparison from these entries.

Why the scoring and analysis details matter

Restorative quality assessed using criteria may involve categories rather than a single continuous measurement. The appropriate statistical approach depends on the scoring scale, the number and meaning of its categories, whether repeated assessments were made, and the paired structure. The registry does not report the detailed FDI scoring categories, a rule for combining criteria, or the statistical model. No particular statistical test or model should therefore be inferred.

In general, categorical outcomes are often presented with counts and proportions, while numerical outcomes may be described with averages or other summaries. If categories are ordered, methods can sometimes make use of that ordering, but the assumptions and interpretation differ from methods for a continuous measurement. If participants have multiple restorations or repeated measurements, their outcomes may also be correlated. The record does not state which outcome format or analysis was used, so none of these approaches can be attributed to this trial.

Missing outcome data also affect interpretation. If some restorations were not assessed, a complete-case analysis would describe only those with observed outcomes. In general, conclusions from such an analysis may be less reliable if missingness is related to the restoration's condition or to participant characteristics. Methods for handling missing observations require information about the amount and pattern of missingness and the analysis assumptions. Participant flow, missing-data methods, and outcome completeness are not reported in the registry record.

How to read planning calculations

Power and sample-size calculations are planning tools. In general, they assess what sample size might be needed to detect a specified effect under stated assumptions about variability, allocation, significance level, and analysis. The registry's planning assumptions describe a two-sided significance level of 0.05, equal allocation between arms, a normal approximation, and an effect defined as a stated fraction of an observed effect. The record also distinguishes calculations expressed as participants per arm from time-to-event calculations expressed as a total number of events.

These assumptions are illustrations, not evidence that the trial was designed with those assumptions or that the enrollment achieved any particular probability of detecting a difference. The record does not report the trial's own sample-size justification. A calculation based on an observed effect is particularly difficult to interpret as trial planning when no primary outcome analysis is listed. In any case, a planned sample size is not observed power: observed power is not a substitute for reporting an effect estimate and its uncertainty.

What the registry analysis fields establish

The record lists seven outcome measures and zero analyses. That means the available registry entries do not provide an analyzed outcome comparison. It does not show whether data were collected but not posted, whether analyses were undertaken outside the registry, or what prompted termination. Those possibilities are not reported in the registry record. Statistical interpretation must therefore remain limited to the design description, outcome definitions, and recorded safety counts, without implying results that the record does not contain.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists seven outcome measures and identifies restorative quality as the primary outcome, with restorative quality, aesthetics, and pain among the secondary outcome topics. Multiple outcomes can create a multiplicity issue: when many hypotheses are tested, the chance of at least one apparently notable result can increase. In general, a prespecified primary outcome and a clearly stated approach to secondary outcomes help readers distinguish confirmatory analyses from exploratory ones. The registry record does not report a multiplicity adjustment, a testing hierarchy, or a statistical analysis plan.

The record does not state whether the listed outcomes were assessed at more than one time point or whether additional outcome categories were analyzed. The primary timeframe is 36 months. Information about outcome changes, prespecification, and any interim analyses is not reported in the registry record. No interim analysis should be assumed.

Missing-data interpretation is also limited. The registry lists enrollment of 16 and identifies the primary outcome population as “Premature termination of study,” but it does not give participant flow, the number completing follow-up, the number with observed endpoint assessments, or reasons for missing assessments. It does not report imputation, sensitivity analyses, or another approach to incomplete outcome data. The effect of missingness on any collected results cannot be assessed from the record.

Analysis populations are not described. The record does not state whether analyses were planned by randomized assignment, restricted to participants with completed restorations, or based on another population. Nor does it identify the analysis unit or say whether the paired split-mouth structure was incorporated. These omissions matter because the choice of population and handling of paired observations can affect both the estimate and its uncertainty. With zero analyses listed, the registry does not provide enough information to determine how any of these issues were handled.

11. Safety Results

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

Deaths

Other (non-serious) adverse events

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

The registry lists zero serious adverse events and zero other adverse events for Restoration With Surefil One Hybrid Composite, with 16 participants at risk. It gives the same figures for Restoration With Venus Pearl Composite: zero serious events and zero other events, with 16 at risk. No deaths are listed in either group. These are the event counts recorded in the registry.

The entries do not establish how long participants were monitored for safety, whether event collection continued through the planned follow-up, or whether all participants contributed information for the same period. The study was terminated, and the record does not explain the timing or circumstances of that termination. It also does not provide event definitions, ascertainment procedures, or a narrative of safety review. These details are not reported in the registry record.

In general, a zero event count is not equivalent to proof that an event cannot occur; it describes what was recorded under the study's observation and reporting procedures. The at-risk counts should not be taken as confirmation that all participants completed the intended follow-up. Accordingly, the figures can be reported as posted, but they do not support a broader conclusion about comparative safety over the planned 3-year period.

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

The registry record documents a randomized investigation comparing two restorative materials for NCCLs. It describes a split-mouth approach, specifies the planned restorative-quality assessment using FDI criteria at 36 months, and lists aesthetics and pain among the secondary outcome topics. It also records enrollment of 16 and a terminated study status. These registry entries describe the intended comparison and the status recorded for the trial.

The record does not report the primary endpoint results or any analyses. It therefore does not show whether the restorative-quality assessments favored either material, whether they were similar, or how uncertain a comparison would be. No effect size, confidence interval, or statistical test result for the primary endpoint is available in the registry entries. The absence of an analysis is not evidence of equivalence or of no difference.

The same caution applies to secondary outcomes. Their names appear in the registry, but outcome estimates and analyses are not reported. The safety entries show zero recorded serious and other adverse events in each group, with 16 participants at risk per group; they do not establish complete observation through the planned follow-up or explain how events were collected.

In general, a trial's design and outcome definitions can clarify what researchers intended to learn, but conclusions about comparative performance require reported observations and an analysis appropriate to the design. Here, the split-mouth structure makes attention to paired data important, yet the registry does not report the statistical method used or whether pairing was accounted for. The label “parallel” also sits alongside detailed split-mouth descriptions without an explanation of the discrepancy.

The record thus supports a description of the study's question, design features, listed outcomes, and termination status, but not a conclusion about which material had better restorative quality or whether the materials differed. The reason for termination, completed follow-up, missing outcome data, and statistical analysis plan are not reported in the registry record. Those gaps limit what can be inferred beyond the reported design and counts.

13. Why This Trial Matters Statistically

This trial is statistically notable because its planned comparison is within participants. In general, split-mouth designs can control for participant-level characteristics shared by the two treatment locations, but they also require analyses that preserve the pairing. A treatment comparison that ignores that structure may give an inaccurate measure of uncertainty. The registry's detailed descriptions indicate a split-mouth design, while its model label says “parallel”; the record does not reconcile the two descriptions or specify the analysis approach.

The trial also illustrates the distinction between a planned endpoint and an available result. Restorative quality was to be assessed using FDI criteria at 36 months, but the primary outcome population is described as premature termination and no analyses are listed. Statistical methods cannot compensate for the absence of reported outcome data. Without outcome estimates, readers cannot assess magnitude, precision, or the compatibility of results with different possible effects.

Termination and incomplete reporting are important to statistical interpretation because they leave questions about follow-up and missingness unresolved. The registry does not report why the study was terminated, how many participants completed the planned follow-up, or whether primary assessments were collected before termination. These are not simply administrative details: they help determine which observations exist and what population an analysis represents.

The registry's planning assumptions also show why sample-size illustrations must be kept distinct from results. Calculations under a stated significance level and modeling approximation are planning exercises, not evidence that an effect was detected or that an analysis was adequately precise. With no primary analysis reported, such planning information cannot establish comparative performance. The record is therefore useful for understanding the intended design and its reporting limits, but not for estimating a treatment contrast.

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 most direct limitation is that the registry reports no primary outcome analysis. The study status is terminated, and the primary outcome population is described as “Premature termination of study.” The reason for termination, whether any primary assessments were completed, and whether results exist outside the registry are not reported in the registry record. No conclusion about comparative restorative quality can be drawn from the posted outcome entries.

The registry lists enrollment of 16, but does not report the number of participants who received both materials, the number assessed at 36 months, or the number included in any analysis. Follow-up completeness, withdrawals, protocol deviations, and missing-data handling are not reported. As a result, the relationship between the enrollment figure and the outcome information available cannot be evaluated.

The design description and model field do not align transparently: detailed arm descriptions specify a split-mouth assignment across upper quadrants, while the model field says “parallel.” The record does not explain this difference. It also does not report the randomization method, allocation concealment, identity of the masked party, or a statistical method that accounts for within-participant pairing.

Further limitations include the absence of reported FDI scoring details, an analysis plan, a sample-size justification for the trial itself, and information about multiplicity or interim analyses. The registry lists secondary outcome topics but gives no results for them. The safety counts do not identify the observation period or completeness of event reporting. These omissions restrict interpretation of both efficacy-related outcomes and safety counts without establishing that any particular method or procedure was or was not used.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Evaluation of Self-adhesive Hybrid Resin Composite Compared to a Traditional Composite Resin in Restorations of NCCLs — NCT05751382.
• Registry record last updated 2025-01-13; status last verified 2024-11.
• Results first posted 2025-01-13.
• 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 describes a randomized, single-masked study comparing Surefil one hybrid composite with Venus Pearl composite for direct restorations of NCCLs. The detailed treatment descriptions specify a split-mouth approach, although the model field is labeled “parallel.” Enrollment is listed as 16, and the study status is terminated.

The primary endpoint was restorative quality assessed using FDI criteria at 36 months. The registry lists seven outcome measures and zero analyses; the primary outcome population is described as “Premature termination of study.” No primary or secondary outcome results are reported. The reason for termination, participant flow, completed follow-up, and statistical analysis plan are not reported in the registry record.

For each material group, the registry records zero serious adverse events, zero other adverse events, and 16 participants at risk. The completeness and duration of safety observation are not specified. Thus, the record documents the intended comparison and recorded safety counts but does not provide an analyzed estimate of comparative restorative quality.