Objectives: A dentifrice containing 0.3% triclosan and 0.2% copolymer in a 0.243% sodium fluoride “high cleaning” silica base (Colgate Total Plus Whitening, Colgate-Palmolive, NY) was developed to address increased consumer demand for products which provide aesthetic toothwhitening benefits. Clinical testing of this dentifrice (Test) has included three published, long term, independent, double blind, clinical studies, in which its effect on the control of extrinsic tooth stain was compared to that of a matching control dentifrice without the high cleaning silica (Colgate Total, Colgate-Palmolive, NY) (Control). The purpose of this investigation was to determine the omnibus conclusion which could be supported by the results of these three studies taken in concert, and to quantitatively evaluate the potential impact of differing inclusion criteria on the overall findings through meta-analytic subset analyses. Methods: Overall summaries and effect size estimates were obtained utilizing standard meta-analytic methods based on a fixed effect model (Hedges and Olkin, 1985). One-sided 95% lower confidence bounds (LCB) for percent improvement were constructed for the overall treatment comparisons. Results: Omnibus means and LCB’s from primary (all data) and selected subset analyses were as follows:
|
Treatment |
Primary |
BL Stain ≥ 1.6 |
BL Stain ≥ 1.7 |
BL Stain ≥ 1.8 |
|
Test |
0.739 |
0.958 |
0.971 |
0.983 |
|
Control |
1.483 |
1.871 |
1.895 |
1.943 |
|
95% LCB |
35.2% |
38.1% |
39.4% |
40.5% |
Conclusion: The meta-analytic overview for the primary study populations suggests a mean advantage of ≥35.2% for the control of extrinsic tooth stain by the triclosan/copolymer/high cleaning silica dentifrice relative to the Control dentifrice. Omnibus findings for the selected subsets do not suggest any dramatically stronger demonstrated effect when the study population consists of higher-stain subjects. (Research supported by the Colgate-Palmolive Co.)