Single-Session Extraoral PBM After Third Molar Extraction: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Single-Session Extraoral PBM After Third Molar Extraction (NCT07522918), a randomized na study. The primary outcome is Postoperative Pain.

2. Clinical Question

The trial also aimed to assess postoperative edema, trismus, and oral health-related quality of life. These outcomes concern different aspects of recovery, and their results cannot be inferred from the pain question. The record identifies the study as randomized, single-masked, and parallel-group. It does not describe the method used to generate the random allocation or who was masked.

The clinical question is therefore about the comparative outcomes following the two assigned approaches, not about whether either approach is preferable for an individual patient. The registry record does not report enough numerical outcome detail to estimate the size or precision of any between-group difference. Nor does it report clinical thresholds for interpreting changes in pain, edema, trismus, or quality of life.

3. Trial Design

The registry record describes a completed randomized controlled trial with a parallel-group model and single masking. The listed enrollment is 70. The intervention was a single-session extraoral dual-wavelength photobiomodulation treatment immediately following extraction; the control group received the standardized extraction protocol without additional photobiomodulation. The listed sponsor is Konya Necmettin Erbakan Üniversitesi. The phase is recorded as NA.

The registry record lists a start date of 2025-02-15 and a primary completion date of 2026-01-20, with status recorded as completed. These are registry fields and do not by themselves establish when results were analyzed or posted. The identity of the masked parties is not reported in the registry record. Details of the randomization sequence, allocation concealment, and procedures used to maintain masking are also not reported in the registry record.

The primary outcome is postoperative pain on a 100-mm visual analog scale, assessed on postoperative day 2 and postoperative day 7. The record also identifies edema, trismus, and oral health-related quality of life as secondary outcomes. It lists four outcome measures and four analyses, but the numerical outcome estimates and detailed analysis methods are not reported in the registry record.

The record does not report eligibility criteria, baseline group characteristics, participant flow, or the numbers analyzed for each outcome. Safety denominators are listed separately for the PBM and control groups. Those safety figures do not establish how many participants contributed data to each efficacy analysis. The record also does not report whether participants were analyzed according to their randomized assignment or how departures from the assigned treatment were handled.

Randomization is intended, in general, to reduce systematic differences between groups at the point of assignment. The benefit of that design for interpreting a particular trial depends on the conduct and reporting of the allocation, follow-up, and analysis. Those details are not reported in the registry record, so the design label alone cannot resolve questions about bias or the completeness of the outcome evidence.

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: Potential participants were screened based on clinical and radiographic criteria (mesioangular impacted mandibular third molars, Pell-Gregory Class IB). A total of 70 eligible patients were randomized into two equal groups.

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 Postoperative Pain, measured over Postoperative Day 2, and Postoperative Day 7..

The primary endpoint is postoperative pain measured using a visual analog scale with a stated range of 0 to 100 mm. The record defines 0 as no pain and 100 as the worst imaginable pain. It specifies assessment on postoperative day 2 and postoperative day 7. The endpoint is recorded as a mean with standard deviation.

A visual analog scale is used to represent a participant’s pain intensity on a continuous scale rather than assigning pain to a small set of categories. In general, this approach can capture gradations in reported experience and allow group summaries such as means. The mean describes the group’s average score; the standard deviation describes how dispersed individual scores are around that average. Neither summary alone shows the full distribution of scores.

Assessing pain at the stated postoperative times allows the trial to examine outcomes at more than one point during early recovery. The registry record does not report the numerical mean or standard deviation for either group at either assessment. It also does not report a between-group estimate, confidence interval, or the analysis used to compare groups. Consequently, the direction, size, and precision of the pain contrast cannot be evaluated from the reported numerical information.

The record does not state a threshold for a change that would be considered important to participants. Statistical differences and clinically meaningful differences are not interchangeable: interpreting importance generally requires an appropriate clinical context and a stated threshold. Such a threshold is not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does the pain score represent?

The primary measure is a continuous pain score on a 100-mm visual analog scale, described as ranging from 0 to 100, with the anchors of no pain and worst imaginable pain. In general, a continuous measure can take values across a scale rather than being limited to a few response categories. A group mean summarizes the average score, while a standard deviation describes the spread of scores around that mean. These summaries answer different questions: the mean describes central tendency, and the standard deviation describes variability among observations.

The registry record specifies a mean and standard deviation as the summary form, but does not report the group values. It also does not report an estimated difference between groups. As a result, readers cannot reconstruct the comparative result or assess whether the group distributions were similar, skewed, or affected by unusual observations. Means and standard deviations alone would not reveal every feature of a distribution, but their absence prevents even a basic numerical comparison.

What does a randomized comparison aim to estimate?

In general, random allocation aims to make treatment groups comparable, on average, with respect to factors that could affect outcomes. A comparison between assigned groups can then estimate the effect of assignment to the intervention relative to assignment to the comparator, subject to the trial’s conduct and analysis. Randomization does not guarantee that every group characteristic will be identical, particularly in a finite study. Reporting baseline characteristics and participant flow helps readers assess how the comparison unfolded.

The record identifies randomized allocation and a parallel design, but does not report the allocation procedure, concealment method, baseline characteristics, or analysis population. The record also does not state whether the primary analysis followed randomized assignment, or how missing outcomes, crossovers, or other deviations were handled. These are important details for understanding which treatment effect the analysis is intended to estimate.

How should uncertainty be read?

In general, an estimate is more informative when accompanied by a measure of uncertainty. A confidence interval gives a range of values compatible with the data under the analysis assumptions. A narrow interval indicates greater precision than a wide interval, though precision does not establish clinical importance or eliminate bias. A p-value is another statistical summary, but it is not a measure of effect size and does not indicate the probability that a treatment works.

The registry record does not report a confidence interval, p-value, or other uncertainty measure for the primary endpoint. It therefore does not allow readers to assess the precision of the stated conclusion. Nor can statistical significance, if any, be inferred from the title. The title’s characterization is not a numerical substitute for an estimated contrast and its uncertainty.

Why might variability affect analysis?

In general, outcome distributions can vary in their spread and shape. If observations are more variable than an analysis assumes, uncertainty estimates can be misleading. For count outcomes, over-dispersion means that the observed variability exceeds what a basic model expects; methods that account for it may be needed. The primary outcome in this trial is described as a continuous pain score, and the registry record does not report whether any distributional checks or alternative methods were used. The record also does not give enough outcome detail to determine whether assumptions were assessed.

For continuous outcomes, analysts may compare group means using a model or a direct contrast, with choices depending on the design, data, and analysis plan. Adjustment for baseline measures can sometimes improve precision when appropriately planned. These are general possibilities, not descriptions of the method used in this trial. The statistical test, model, covariates, and any adjustments are not reported in the registry record.

What do the planning assumptions mean?

The record describes a sample-size planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation. It also states that the effect to detect is a stated fraction of the observed effect. Such illustrations are planning scenarios, not observed trial results and not evidence that a study had a particular probability of detecting an effect after completion. The record does not report the computed planning estimates or the fractions used.

In general, sample-size calculations depend on assumptions about the target effect, variability, significance level, allocation, and analysis. If the target effect is smaller than an observed estimate, planning for it generally requires more information than planning for the larger estimate, all else held constant. This is a general statistical relationship, not a calculated result for this trial. The record does not report a protocol-based sample-size justification, and the planning illustration should not be described as the trial’s original design rationale or as observed power.

The stated assumptions do not resolve the missing outcome reporting. Planning calculations address what a future or planned study might require under specified assumptions; they do not supply the observed group values, effect estimate, or uncertainty for the completed trial. Those outcome statistics are not reported in the registry record.

10. Multiplicity, Missing Data and Analysis Populations

The primary pain endpoint is assessed on postoperative day 2 and postoperative day 7, and the record also identifies edema, trismus, and oral health-related quality of life as secondary outcomes. Considering several outcomes or assessment times raises a general multiplicity question: the more comparisons examined, the greater the chance that at least one result may appear statistically unusual by chance when no true effect exists. Whether and how to adjust for multiple comparisons depends on the prespecified questions and analysis plan.

The registry record does not report whether the day-specific pain comparisons were treated as separate primary analyses, whether a hierarchy was used, or whether any multiplicity adjustment was planned or applied. It also does not report which statistical tests were used for the secondary outcomes or whether those analyses were adjusted. The presence of multiple endpoints alone does not establish that results are invalid, but the absent analysis details make it difficult to assess how the findings should be interpreted together.

Missing-data methods and analysis populations are also not reported in the registry record. The record does not describe outcome completion by group, the extent or pattern of missing observations, or any method used to handle missing measurements. In general, missing outcomes can affect a comparison when the likelihood of missingness is related to participant characteristics or outcomes. The direction and size of any resulting bias cannot be determined without information about missingness and the analysis.

The record does not state whether participants were analyzed according to randomized assignment, whether a per-protocol analysis was conducted, or how treatment deviations were handled. These details are relevant to understanding the estimand and the potential effects of post-randomization exclusions. No assumptions about missing data, analysis populations, or multiplicity procedures should be inferred from the design labels or title.

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 safety figures list the PBM group and control group separately, with 35 participants at risk in each group. For both groups, the record lists zero serious adverse events, zero other adverse events, and zero deaths. These are the figures recorded for the safety categories; they are not efficacy outcomes and do not establish a comparative effect on pain, edema, or trismus.

In general, an observed count of zero means that no events in that category were recorded in the listed group during the reported collection period. It does not prove that the underlying risk is zero. The interpretation depends on how events were defined, how actively they were sought, the duration of follow-up, and the completeness of reporting. Those safety-collection details are not reported in the registry record.

The record does not report adverse-event definitions, timing, severity beyond the listed serious/other categories, relatedness assessments, or the observation period. It also does not report whether there were withdrawals or incomplete safety follow-up. Therefore, the zero counts should be read as the registry’s reported counts, not as evidence that adverse events are impossible or that the groups have equivalent safety profiles. No broader safety conclusion can be drawn from these figures alone.

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

The registry record identifies a focused comparison: a single 10-minute extraoral photobiomodulation session immediately after impacted mandibular third molar extraction versus the same surgical protocol without additional photobiomodulation. It identifies postoperative pain on day 2 and day 7 as the primary outcome and lists edema, trismus, and oral health-related quality of life among the secondary outcomes. The record’s title characterizes the findings as reduced early pain but not edema or trismus.

That conclusion cannot be quantified from the numerical results reported in the registry record. Group means, standard deviations, between-group estimates, and uncertainty measures are not reported for the pain assessments. Numerical results for edema, trismus, and quality of life are also not reported. Without those results, the size and precision of the claimed differences cannot be judged, and the title should not be treated as a complete statistical report.

The title’s statement that edema and trismus were not reduced does not demonstrate that the groups were identical. In general, evidence of no statistically detectable difference is distinct from evidence that any difference is too small to matter. Assessing that distinction requires estimates, uncertainty, and an appropriate clinical threshold; these are not reported in the registry record. The record also does not provide a stated threshold for an important change in pain or the secondary outcomes.

The record lists zero serious adverse events, zero other adverse events, and zero deaths in each group among the safety denominators reported. These observations describe the recorded safety counts but do not establish the absence of risk, particularly without details about event definitions and follow-up.

Accordingly, the record supports describing the trial design, treatment contrast, outcome timing, and the conclusion stated in its title. It does not support a numerical estimate of treatment effect, a judgment about precision or clinical importance, or a definitive conclusion about the secondary outcomes or safety. Those distinctions are essential when interpreting a trial whose registry record lacks detailed outcome estimates.

13. Why This Trial Matters Statistically

This trial addresses a practical statistical question: whether a defined, single-session intervention is associated with differences in patient-reported pain and other postoperative outcomes compared with the same extraction protocol without that intervention. Its randomized, parallel-group design is relevant because random allocation is intended, in general, to support a fair comparison between assigned groups. The record also specifies the treatment timing, delivery approach, comparator, and pain assessment times, which helps define the clinical contrast under study.

The case also illustrates why a trial’s title or conclusion cannot replace its outcome estimates. A statement that pain was reduced, or that an outcome was not reduced, is difficult to evaluate without group summaries, a comparative estimate, and a measure of uncertainty. Statistical interpretation depends on both direction and magnitude, and precision helps distinguish a well-estimated small effect from an uncertain estimate. Those numerical details are not reported in the registry record.

Multiple outcomes and assessment times create further interpretive questions. A reader needs to know which comparisons were primary, how multiplicity was handled, what analysis populations were used, and how missing observations were addressed. The record does not report these methods. Their absence does not establish that the trial was improperly conducted, but it limits what can be assessed from the registry information.

The planning illustration also highlights a distinction between study design and observed evidence. Planning assumptions can describe hypothetical requirements under specified conditions, but they are not observed power and do not answer whether an estimated effect is clinically important. The registry record does not report the computed planning estimates or a protocol-based sample-size justification.

For biostatistical interpretation, the key lesson is that conclusions are strongest when readers can inspect the estimates, their uncertainty, and the analysis choices behind them. The record gives meaningful design context, but incomplete numerical outcome reporting leaves the central comparative claims difficult to evaluate independently.

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.

A principal limitation of the registry record is that it does not report numerical outcome results. For the primary pain measure, group means, standard deviations, between-group estimates, and uncertainty measures are not reported for postoperative day 2 or postoperative day 7. Numerical estimates for edema, trismus, and oral health-related quality of life are also not reported. This prevents assessment of effect size, variability, and precision.

Methods needed to evaluate the comparisons are also not reported. The record identifies randomized allocation and single masking, but does not describe sequence generation, allocation concealment, who was masked, or how masking was maintained. Baseline characteristics, participant flow, outcome completion, and analysis populations are not reported. The methods used to address missing data, protocol deviations, and multiplicity are also not reported in the registry record.

The record does not specify clinical thresholds for meaningful changes in the outcomes. It therefore does not allow a reader to distinguish a statistically detectable difference from one that would be considered important in the clinical context. The title’s characterization of pain, edema, and trismus does not resolve that limitation because it does not supply estimates or uncertainty.

The safety record lists zero serious adverse events, zero other adverse events, and zero deaths in each group, but event definitions, collection methods, and follow-up duration are not reported. These omissions limit interpretation of the safety counts. The record also does not report a protocol-based sample-size justification; the stated planning illustration is based on an observed effect and should not be treated as the trial’s design rationale or observed power.

These are limitations of what is reported in the registry record. They do not establish that the underlying trial lacked these methods or data, only that those details are not reported in the registry record.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Single-Session Extraoral PBM After Third Molar Extraction — NCT07522918.
• Registry record last updated 2026-06-09; status last verified 2026-04.
• Results first posted 2026-06-09.
• 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 completed randomized, single-masked, parallel-group trial of extraoral dual-wavelength photobiomodulation after impacted mandibular third molar extraction. Listed enrollment is 70. The PBM group received a single 10-minute 650+904 nm session immediately after extraction; the control group received the same standardized extraction protocol without additional photobiomodulation.

The primary outcome is pain on a 100-mm visual analog scale, assessed on postoperative day 2 and postoperative day 7. Edema, trismus, and oral health-related quality of life are listed as secondary outcomes. The title characterizes the study as finding reduced early pain but not edema or trismus. Numerical outcome estimates and uncertainty measures are not reported in the registry record, so the size and precision of those findings cannot be assessed from the posted information.

The safety record lists zero serious adverse events, zero other adverse events, and zero deaths in each group, with 35 at risk per group. Detailed methods for allocation, masking, missing data, analysis populations, and multiplicity are not reported in the registry record.