Whitening dentifrice and tooth surface discolorationa systematic review and meta-analysis

ObjectiveThe aim of this systematic review was to assess the effect of a whitening dentifrice (WDF) relative to a regular dentifrice (RDF) on the reduction of natural extrinsic tooth surface discoloration (ETD). Materials and methodsThe MEDLINE-PubMed, Cochrane-CENTRAL and EBSCO-Dentistry and Oral Sciences databases were searched, up to April 2017. The inclusion criteria were as follows:(randomized)controlled clinical trials, healthy subjects 18years of age, studies comparing WDF with RDF, a follow-up period of at least 6weeks and studies scoring ETD as the stain area/extent, stain intensity or a composite score. Studies using an induced staining model were excluded. ResultsIndependent screening of 851 unique papers resulted in 21 eligible publications, which included 32 comparisons. The descriptive analysis illustrated that the majority of comparisons showed a significant effect on ETD, in favour of WDF over RDF. The meta-analysis substantiated this observation and revealed that the difference of means (diffM) comparing WDF and RDF was a reduction for stain area of -0.44 [(95% CI: -0.55; -0.339) (P <.00001)] according to the original Lobene Stain Index; this result is in favour of the WDF. For the modified Lobene Stain Index, the diffM was -0.41 [(95% CI: -0.71; -0.10) (P=.009)]. For overall stain intensity, the diffM was -0.35 [(95% CI: -0.44; -0.25) (P <.00001)], and the composite score was -0.39 [(95% CI: -0.57; -0.21) (P <.0001)] and -0.54 [(95% CI: -0.66; -0.43) (P <.00001)]. Subgroup analysis differentiating between products that contained added chemical antidiscoloration agents showed a similar pattern. ConclusionIn this review, nearly all dentifrices that are specifically formulated for tooth whitening were shown to have a beneficial effect in reducing ETD, irrespective of whether or not a chemical discoloration agent was added