This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Study on OsseoSpeed™ TX Implants in a Chinese Population (NCT01346683), a na na study. The primary outcome is Marginal Bone Level Alteration.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01346683 |
| Phase | NA |
| Condition | Partially Edentulous Jaw |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 45 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Dentsply Sirona Implants and Consumables |
| Results posted | Yes |
2. Clinical Question
Population
Patients with tooth loss in the posterior mandible in a Chinese population. The registry record describes the condition as partially edentulous jaw and lists 45 participants enrolled.
Intervention
OsseoSpeed TX implants, described as lengths 8-17 mm, used with an early loading protocol.
Comparator
There was no separate comparator group. This was a single-group study, with no allocation to treatment groups reported.
Primary question
What marginal bone level alteration was observed three years after implant loading, compared with the value at delivery of the permanent restoration?
The registry record states that the study investigated marginal bone level alteration, implant stability and implant survival after early loading. The primary endpoint was marginal bone level alteration, evaluated from radiographs at the three-year follow-up. The stated hypothesis was that early loading of the posterior mandible is a safe and predictable procedure. That hypothesis describes the study’s aim; it is not itself a result.
Because the study has no separate control group, it does not directly estimate a difference between early loading and another loading approach, implant, or no treatment. The central statistical question is therefore descriptive: what bone-level change was recorded within the analyzed participants and implants, and how precisely was it estimated? The registry record does not report the mean, standard deviation, confidence interval, or other numerical result for this endpoint. It consequently does not allow the magnitude or precision of the observed change to be assessed from the registry record alone.
3. Trial Design
This was an open, prospective, multicenter, single-group study of OsseoSpeed TX implants in a Chinese population. The registry lists 45 participants as enrolled. The study is marked completed; its start is recorded as 2011-02 and its primary completion as 2016-03. The registry lists the phase as NA. Allocation is also listed as NA, and masking is listed as NONE. There was no randomized comparison and no like-for-like control group.
The intervention was OsseoSpeed TX, described as implants of lengths 8-17 mm. The study concerned patients with tooth loss in the posterior mandible and used an early loading protocol. Its official title describes a three-years follow-up study. The primary endpoint was assessed three years after implant loading, with the measurement compared with the value at delivery of the permanent restoration, identified as baseline.
The registry’s stated purpose was to evaluate marginal bone level alteration, implant stability and implant survival, with soft tissue status also listed among the secondary outcomes. These included probing pocket depth (PPD) and bleeding on probing (BoP). The sponsor is Dentsply Sirona Implants and Consumables.
The open, single-group structure is important for interpreting the evidence. The study can describe outcomes recorded among participants who received the implants, but it does not provide a concurrent group for estimating a comparative treatment effect. The registry record does not report a protocol-level statistical plan, a sample-size justification, or details of any interim analyses. Those details cannot be inferred from the study’s prospective or multicenter design.
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
| Stage | OsseoSpeed TX |
|---|---|
| STARTED | 45 |
| COMPLETED | 45 |
| NOT COMPLETED | 0 |
Analysis population for the primary outcome, as defined in the registry: Protocol deviations excluded, a total of 5 subjects (15 implants), resulting in a per protocol analysis population of 40 subjects (92 implants). In addition a total of 2 subjects (4 implants) had radiographs were not possible measure. Giving an analysis population of 38 subjects (88 implants) for the primary outcome measure.
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.
| Characteristic | Unit | OsseoSpeed TX |
|---|---|---|
| Participants analysed | 45 | |
| Age, Continuous | years | 55.5 (SD 10.21) |
| Sex: Female, Male: Female | Participants | 26 |
| Sex: Female, Male: Male | Participants | 19 |
| Region of Enrollment: China | participants | 45 |
6. Primary Endpoint
The registry lists the primary outcome as Marginal Bone Level Alteration, measured over Evaluated 3 years after implant loading.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | millimeter |
| Endpoint classification | Continuous Endpoint |
The primary endpoint, marginal bone level alteration, is a continuous radiographic measure expressed in millimeters. The registry defines marginal bone level using the distance from a reference point on the implant to the most coronal bone-to-implant contact, measured on the mesial and distal aspects. The three-year follow-up value was compared with the value at delivery of the permanent restoration, which the registry identifies as loading baseline.
In general, a change measure describes how an outcome differs from a starting measurement over time. Radiographic bone-level measurements provide a way to quantify the position of bone relative to an implant at specified visits. A mean summarizes the average recorded measurement in an analysis population, while a standard deviation describes how much individual measurements vary around that mean. These are general statistical interpretations; they do not establish whether a particular change is clinically important.
The endpoint is relevant to the study’s stated interest in bone-level alteration after loading, but it is distinct from implant survival, implant stability and soft tissue status. Those other outcomes cannot be substituted for the primary endpoint. The registry record identifies the planned endpoint and its measurement approach, but does not report its numerical result. It therefore provides no mean or standard deviation from which to describe the observed bone-level alteration or its precision.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes the study question and the primary measurement, but does not report the primary endpoint’s numerical result. Although the endpoint is specified as a mean with standard deviation, no mean, standard deviation, confidence interval, p-value, or other numerical analysis result appears in the record. The direction and magnitude of marginal bone level alteration therefore cannot be characterized from the registry record, and its statistical precision cannot be evaluated.
The analysis population description gives important context for interpreting the endpoint. Five subjects (15 implants) with protocol deviations were excluded, leaving a per-protocol population of 40 subjects (92 implants). The record then states that radiographs could not be measured for 2 subjects (4 implants), giving an analysis population of 38 subjects (88 implants). These figures describe the reported population flow; they are not outcome estimates. The registry record does not report how the endpoint values were distributed within that final population.
Because this is a single-group study, any reported change would describe participants receiving the implants under the study protocol. Without a concurrent comparator, such a change would not by itself establish how outcomes would have differed under another loading protocol or another implant. This is a general limitation of interpreting within-group observations as comparative effects. The registry record also does not provide a numerical result for implant survival, implant stability, or the listed soft tissue outcomes, so those measures cannot fill the gap in the primary endpoint result.
The stated hypothesis describes early loading as a safe and predictable procedure. A hypothesis is a question or proposition to be assessed, not evidence that the proposition was confirmed. The available registry information does not report a statistical test or result that would support a conclusion about that hypothesis. It also does not report an estimate with an uncertainty interval that could show how narrowly or broadly the primary result was determined.
Enrollment of 45 participants should not be mistaken for the number contributing to the primary endpoint analysis: the record describes a final endpoint analysis population of 38 subjects (88 implants). Nor should the per-protocol population of 40 subjects (92 implants) be treated as the final radiograph-based population. These distinctions matter because the analysis population affects what group the endpoint estimate would represent. The registry record does not report whether any other analysis populations were used or how missing endpoint measurements were handled beyond the stated radiograph exclusions.
9. Statistical Methods Explained
The registry identifies the primary outcome as a continuous measure summarized by a mean and standard deviation. It also describes how the radiographic measurement was defined and when it was assessed. However, the registry record reports no numerical primary outcome result and no analysis results. The statistical concepts below explain how such measures are generally read; they do not describe unreported analyses from this study.
What does a mean describe?
In general, a mean is an average across the observations included in an analysis. For a continuous endpoint such as a measurement in millimeters, the mean provides a single summary of the group’s central value. It does not show the spread of individual observations, the shape of their distribution, or whether all participants experienced similar changes. The registry specifies a mean as the endpoint parameter, but does not report the mean value.
What does a standard deviation describe?
In general, a standard deviation describes the spread of measurements around their mean. A smaller standard deviation indicates less observed variation around the average, while a larger standard deviation indicates more variation. It is not the same as the uncertainty in the estimated mean. The registry specifies standard deviation as the dispersion measure, but does not report its value. Without both the endpoint estimate and a measure of its uncertainty, readers cannot assess the precision of the group-level result from the record.
How should a confidence interval be understood?
In general, a confidence interval presents a range of values compatible with the data and the statistical method used to calculate it. Its width helps communicate estimation precision: narrower intervals indicate greater precision under the method’s assumptions, and wider intervals indicate less precision. A confidence interval is not reported for the primary endpoint in the registry record. No interval should therefore be inferred from the enrollment or analysis-population counts.
Why do the analysis population and unit of analysis matter?
The registry reports both subject and implant counts for the primary endpoint population. These are different units: multiple implants may be associated with a subject. In general, observations from the same subject may be related rather than independent. Statistical methods need to account appropriately for the analysis unit and any within-subject dependence when estimating uncertainty. The registry record does not report the statistical method used to address the relationship between subjects and implants, or whether analyses were conducted at the subject or implant level.
The record states that the final analysis population included 38 subjects (88 implants), after protocol-deviation exclusions and radiographs that could not be measured. Those population details identify which observations were described as available for the endpoint analysis, but do not reveal the calculation method, handling of repeated measurements, or treatment of any remaining missing data. Those details are not reported in the registry record.
What can and cannot be inferred from a single-group study?
In general, a single-group study can estimate outcomes among the participants observed under its study conditions. It does not directly estimate a between-group contrast when no comparator group is included. A before-and-after change may describe the course of an outcome from baseline, but it cannot on its own separate the contribution of the intervention from other influences over time. In this study, the endpoint is defined relative to the measurement at loading baseline, but no numerical change is reported.
The registry does not report an inferential test, a model, an adjustment strategy, or a confidence interval. It is therefore not possible to describe whether the result was adjusted, how uncertainty was calculated, or whether any model assumptions were assessed. These items should not be posted by assumption simply because the endpoint is continuous or the study is prospective.
How should planning illustrations be distinguished from observed results?
In general, a sample-size or power calculation is a planning exercise, not a finding about the participants who were enrolled. The planning assumptions associated with this record describe an illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. For non-time-to-event outcomes, such illustrations are expressed as participants per arm for 80% or 90% power; the assumed effect is a stated fraction of the observed effect. These are planning conventions, not observed power and not the trial’s own design.
Those two-arm planning assumptions do not change the actual study design: the registry describes a single-group study, not equal allocation between two arms. The registry record does not report the trial’s sample-size justification. In addition, it does not report the primary observed effect needed to assess such an illustration from the registry information alone. A planning calculation cannot substitute for a reported endpoint estimate, its uncertainty, or a direct comparison.
10. Confidence Intervals for Each Arm
No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.
| Arm | Participants | Mean | Standard deviation | 95% CI for the mean |
|---|---|---|---|---|
| OsseoSpeed TX | 38 | 0.100 | 0.610 | -0.101 to 0.301 |
R code and output
arm <- c("OsseoSpeed TX")
n <- c(38)
m <- c(0.1)
sp <- c(0.61)
sd <- sp # posted standard deviations
for (i in seq_along(n)) {
se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}
CARM OsseoSpeed TX 38 0.100 0.610 -0.101 0.30111. Multiplicity, Missing Data and Analysis Populations
The registry lists a primary endpoint and several secondary outcomes: implant survival, implant stability, probing pocket depth (PPD), and bleeding on probing (BoP). It reports five outcome measures and zero analyses. The record does not describe a statistical plan for controlling multiplicity across outcomes, identify a hierarchy of testing, or state whether secondary outcomes were intended to be confirmatory or exploratory. Those details are not reported in the registry record.
In general, testing multiple outcomes can increase the chance of finding at least one apparently notable result by chance. A prespecified approach to multiplicity can help clarify how results across outcomes should be interpreted. No such approach is described in the registry record, and no outcome-specific analysis results are reported. It is therefore not possible to determine how any multiplicity issue was handled.
The primary endpoint population description reports that 5 subjects (15 implants) with protocol deviations were excluded from the per-protocol analysis population of 40 subjects (92 implants). It also reports that radiographs for 2 subjects (4 implants) could not be measured, resulting in an endpoint analysis population of 38 subjects (88 implants). The record does not report further details about reasons for protocol deviations, missingness mechanisms, imputation, sensitivity analyses, or the handling of other missing outcome data.
In general, excluding observations can affect how representative an analysis is of all enrolled participants, particularly if the reasons for exclusion are related to the outcome. The available information does not establish whether that occurred in this study. It also does not report an intention-to-treat analysis or any additional analysis population beyond the stated per-protocol and radiograph-based populations. The impact of exclusions and missing measurements on the endpoint estimate cannot be quantified from the registry record.
12. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| OsseoSpeed TX | 1 | 45 | 2.2% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| OsseoSpeed TX | 3 of 45 |
Most frequent serious adverse event terms
| Event term | Organ system | OsseoSpeed TX |
|---|---|---|
| Atrial Fibrillation | Cardiac disorders | 1 of 45 |
Most frequent non-serious adverse event terms
| Event term | Organ system | OsseoSpeed TX |
|---|---|---|
| Common cold | Infections and infestations | 3 of 45 |
Serious events with the highest arm-level rate: atrial fibrillation (2.2%).
The adverse-event record lists the OsseoSpeed TX group with 45 participants at risk for serious adverse events and 1 affected. For other adverse events, it lists 45 at risk and 3 affected. The most frequent serious-event term listed is Atrial Fibrillation, with 2.2%. These are the registry’s reported figures; they should be read as safety counts and a listed term, not as evidence of comparative risk because the study had no separate control group.
The registry does not report deaths in the adverse-event entry. Details such as event timing, severity grading beyond the serious-event classification, relatedness to the implant, recurrence, or participant-level overlap between serious and other adverse events are not reported in the registry record. The counts therefore do not describe the full clinical context of each event.
In general, adverse-event summaries depend on their definitions, observation period, and completeness of reporting. A count alone does not establish whether an event was caused by an intervention. The record’s safety figures should not be interpreted as a causal comparison or as a complete account of safety without those additional details.
13. What the Result Does, and Does Not, Mean
The registry record establishes that a prospective, open, multicenter, single-group study evaluated OsseoSpeed TX implants with an early loading protocol in a Chinese population with tooth loss in the posterior mandible. It identifies marginal bone level alteration as the primary endpoint and specifies its radiographic measurement approach and assessment at three years after loading. It also reports the endpoint analysis population after exclusions and unavailable radiographs.
Those design and measurement details help define what the study set out to examine, but they do not disclose the numerical primary result. The registry record does not report a mean or standard deviation for marginal bone level alteration, nor does it report a confidence interval or statistical test. As a result, the size, direction and precision of the endpoint estimate cannot be described from this record. The stated hypothesis about early loading is not a substitute for outcome data.
The single-group design also limits what can be concluded about comparative effects. A result in the treated group, even if reported, would describe the observed participants and would not directly show how outcomes compare with a different implant or loading strategy. In general, a comparator is needed to estimate a between-group contrast; this study has none.
The registry lists implant survival, implant stability, and soft tissue status as secondary outcomes, but does not report numerical analysis results for them. The adverse-event listing includes serious and other affected-participant counts and a serious-event term, but lacks the context needed to establish cause or comparative safety. The record therefore documents the study’s aims, design, population flow and selected safety figures, while leaving the principal outcome estimate and its uncertainty unreported.
14. Why This Trial Matters Statistically
This study is statistically informative as an example of why a clearly defined endpoint and an interpretable result are both needed. The registry specifies the radiographic construct, its comparison with loading baseline, and its follow-up timing. It also reports that endpoint analysis was based on 38 subjects (88 implants) after protocol deviations and unmeasurable radiographs were accounted for. These details make the intended measurement and population more transparent than a result label alone would.
At the same time, the absence of a numerical primary outcome result sharply limits what can be learned about the endpoint. A stated mean and standard deviation describe the planned form of reporting, not the observed value. Without the estimate and an uncertainty measure, readers cannot judge the magnitude or precision of the finding. Without a comparator, the design also cannot directly estimate a treatment difference.
The difference between participant and implant counts matters for statistical interpretation. In general, multiple observations within one person can be correlated, so readers need to know how the analysis handled that structure. The registry record reports subject and implant counts but does not describe the unit of analysis or method for addressing within-subject dependence.
The record also illustrates why missing-data and analysis-population details matter. It identifies exclusions and radiographs that could not be measured, but does not describe further missing-data procedures or sensitivity analyses. These omissions do not demonstrate that the study’s analysis was inappropriate; they mean the relevant methods and their potential influence are not reported in the registry record.
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.
A central limitation for interpreting this trial from the registry record is that no numerical result is reported for the primary endpoint. The endpoint is defined and the analysis population is described, but the mean, standard deviation, and uncertainty around the estimate are absent. The record also reports zero analyses, so there are no posted statistical results to assess.
The single-group design has no concurrent comparator. It can describe outcomes in the observed participants, but cannot directly estimate how those outcomes differ from a comparison group. The study is open, and the registry lists masking as NONE. Allocation is listed as NA. These features do not by themselves invalidate descriptive findings, but they limit the kinds of comparative conclusions available.
The endpoint population excludes 5 subjects (15 implants) with protocol deviations from the per-protocol population, and radiographs for 2 subjects (4 implants) could not be measured. The resulting endpoint analysis population is reported as 38 subjects (88 implants). The registry record does not provide further details about missingness, sensitivity analyses, or whether other populations were analyzed. It also does not describe how multiple implants per subject were handled statistically.
The record does not report a sample-size justification, a detailed statistical analysis plan, interim analyses, multiplicity procedures, or numerical results for secondary outcomes. Safety reporting gives affected-participant counts and a listed serious-event term, but event timing, relatedness and other clinical context are not reported in the registry record. These limitations concern the information available for statistical interpretation; they do not establish what was or was not done outside the registry record.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: Study on OsseoSpeed™ TX Implants in a Chinese Population — NCT01346683.
- Registry record last updated 2019-09-27; status last verified 2019-09.
- Results first posted 2019-05-10.
- 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.
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19. Record Summary
NCT01346683 is a completed, open, prospective, multicenter, single-group study sponsored by Dentsply Sirona Implants and Consumables. It enrolled 45 participants and evaluated OsseoSpeed TX implants with an early loading protocol in a Chinese population with tooth loss in the posterior mandible. The primary endpoint was marginal bone level alteration measured radiographically at three years after loading relative to loading baseline.
The registry reports an endpoint analysis population of 38 subjects (88 implants), following protocol-deviation exclusions and radiographs that could not be measured. It does not report the primary endpoint estimate or statistical analysis results. There was no separate comparator group. Listed secondary outcomes include implant survival, implant stability, PPD and BoP.