Clinical studies to determine the effectiveness of a whitening toothpaste at reducing stain (using a forced stain model)

Efficacy and Adverse Effects of Whitening Dentifrices Compared With Other Products: A Systematic Review and Meta-analysis

Whitening dentifrices (WDs) are widespread and accessible worldwide, claiming to whiten teeth. Therefore, this systematic review aimed to assess the extrinsic stain removal (ESR), the whitening potential, and the adverse effects of WDs. Randomized controlled trials comparing WDs with regular dentifrices (RDs) and other home-based whitening products were searched at NCBI-PubMed, Cochrane-CENTRAL, EBSCO-Host, and clinicaltrials.gov. The studies were screened and had data extracted by two independent researchers. Eligible studies presented outcomes of ESR, color change, and adverse effects, with no restriction of publication date. Data were meta-analyzed using RevMan 5.3, and the level of evidence was rated according to GRADE criteria. Eleven studies (n=1962) assessed reduction of stain area and intensity through Lobene Stain index, with a mean difference (MD) of -0.33 ([-0.41;-0.25]; p=0.00001) and -0.34 ([-0.44;-0.25]; p=0.00001), respectively. When the modified Lobene Stain index was used (six studies; n=2576), MD was -0.42 ([-0.58;-0.25]; p=0.00001) and -0.30 ([-0.39;-0.21]; p=0.00001), respectively. Mean color change through shade guide tabs (three studies; n=1322) was -1.80 ([-2.33;-1.26]; p=0.00001). All differences were in favor of the WDs, which also produced a risk of adverse effects (RR=1.74; [1.20, 2.52]; p=0.003; four studies; n=1322). The comparison of WDs with paint-on gel (two studies; n=58) yielded similar efficacy and adverse effects (p>0.05), whereas the comparison of WDs with white strips (two studies; n=87) yielded higher efficacy of the latter (p=0.00001) and similar adverse effects (p=0.52). The quality of evidence varied from low to moderate. WDs are more effective in reducing extrinsic stain and producing a whitening-like effect in teeth than RDs, although they also produce more adverse effects. Whitening efficacy of WDs is similar to paint-on gel and lower than white strips. Higher-quality evidence demands larger, well-conducted, independent studies.

Efficacy of Three Toothpastes in Iron Stain Removal from Primary Teeth

Aim

This study aimed to assess the iron stain removal efficacy of three toothpastes in extracted primary teeth.

Materials and methods

In this in vitro study, 60 extracted sound primary teeth were selected, decoronated at the cementoenamel junction, and their pulp chambers were filled with a composite. The teeth were then immersed in ferrous sulfate solution and brushed 3,000 times in an automatic tooth-brushing machine using Colgate, whitening Crest, and conventional Crest dentifrices. Stain removal was done in four groups using a prophylaxis paste. Digital images were obtained from the teeth before and after brushing with dentifrices and the changes in color parameters were measured using Photoshop and iColor software programs. Changes in color parameters were statistically analyzed using one-way ANOVA while multiple comparisons were done by Tukey's test.

Results

The greatest change in chroma was observed in the prophylaxis group and then in the whitening Crest, Colgate, and conventional Crest (mean values of −65.2, −31.07, −21.27, and −0.73, respectively). Prophylaxis completely removed the stains. The greatest reduction in value occurred in conventional Crest, Colgate, and whitening Crest (−18.07, −12.23, and −0.4, respectively). In the L*a*b* system, the least reductions were noted in the whitening Crest, Colgate, and conventional Crest (mean values of −1.96, −3.92, and −3.37, respectively). Prophylaxis significantly improved tooth brightness (a mean increase of 4.26).

Conclusion

None of the toothpastes in this study were capable of effectively removing iron stains. Crest whitening toothpaste was slightly effective in this regard.

Clinical significance

Iron drops are routinely prescribed for children younger than 2 years of age to prevent iron deficiency and iron deficiency anemia. However, iron stains on teeth are a common concern for many parents. Finding toothpastes with greater efficacy for iron stain removal can help in this respect.

How to cite this article

Heidari A, Shahrabi M, et al. Efficacy of Three Toothpastes in Iron Stain Removal from Primary Teeth. Int J Clin Pediatr Dent 2019;12(1):10–14.

Toothpaste Composition Effect on Enamel Chromatic and Morphological Characteristics: In Vitro Analysis

The aim of this in vitro study was to assess the effect of toothpastes, with different compositions, on optical and morphological features of sound and demineralized enamel. We selected twenty-five teeth, recently extracted for orthodontic purposes, for this in vitro study. The teeth were caries free, without stains, fissures, filling or hypoplasia observed at inspection under standard conditions. Teeth were brushed (for 2–3 min, twice a day, for 21 days), with five different toothpastes (four commercially available and an experimental one) containing fluoride and hydroxyapatite. After that, teeth were demineralized with 37% orthophosforic acid (Ultra Etch^®, Ultradent Products Inc., South Jordan, UT, USA) for 60 s. We repeated the brushing protocol for another 21 days on demineralized enamel. Enamel vestibular surfaces were examined using a spectrophotometer (Vita EasyShade -Vita Zahnfabrik, Bad Sackingen, Germany) and a Scanning Electron Microscope (Inspect S^®, FEI Company, Hillsboro, OR, USA). Differences were statistically significant for colour parameters L* and ΔE*. SEM evaluation reveals demineralized enamel mineral gain after brushing with selected toothpastes. Toothpastes with specific ingredients can represent a balance between aesthetic and mineralization, and an oral hygiene correct algorithm is able to preserve enamel characteristics during ortodontic treatement with fixed appliances.

Clinical evaluation of the whitening effect of over-the-counter dentifrices on vital teeth

This randomized clinical trial evaluated the whitening potential of commercially available toothpastes. Sixty patients were selected and randomly divided into 4 groups (n=15), according to the dentifrice used: GI (control) - Colgate Total 12, GII - Close-up White Now, GIII: Oral-B 3D White, GIV: Colgate Luminous White. Three daily brushings were performed for 2 to 3 min each, during a period of 15 days. Patients had the color of their teeth evaluated before and after the treatment by means of a spectrophotometer (Vita EasyShade - CIE L*a*b*). Data obtained from L values were analyzed by one-way ANOVA and t test. ∆E was also evaluated to calculate color alteration, by NBS criteria. Mean (standard deviation) of initial values were GI: 82.9 (4.9); GII: 83.9 (5.8); GIII: 83.9 (7.2); GIV: 86.4 (3.4) and final values were GI: 84.1 (6.3); GII: 84.6 (6.1); GIII: 84.2 (7.1); GIV: 88.2 (2.8). In conclusion, the dentifrices showed no lightening action on vital teeth, except for Colgate Luminous White; but according to NBS criteria, there was no noticeable visible change to the patients in any group.

Tooth staining potential of experimental amine fluoride/stannous fluoride mouth rinse formulations-a randomized crossover forced staining study

OBJECTIVES

It was the aim to investigate experimental mouth rinses concerning their tooth and tongue staining potential using the standardized short-term forced staining model.

MATERIALS AND METHODS

A single centre, clinically controlled, randomized, investigator-blinded study was conducted in a crossover design. In healthy dental students, three experimental AmF/SnF2 (A, B, C) mouth rinses and a phenolic/essential oil rinse (D) were compared to a water control (E). Four treatment days consisted of eight hourly rinses with mouth rinse and black tea. Mechanical oral hygiene was ceased. At the fifth day, tooth and tongue staining indices were recorded. Between treatment periods, a 10-day washout phase was performed.

RESULTS

Twenty-eight participants entered and completed the study. All mouth rinses including the water control led to tooth and tongue staining. Most tooth staining occurred after rinsing with test rinse A, followed by B, D, C and E. Statistically significant differences existed between products A and C, D, and E. Most tongue staining happened in group B, followed by A, D, C and E (not statistically significant).

CONCLUSION

Within the limitations of the model, mouth rinse C has a promising potential of causing less tooth discoloration than other AmF/SnF2 rinses. C is highly recommended to be investigated in further long-term clinical studies on its in vivo staining potential and antiplaque efficacy.

CLINICAL RELEVANCE

This forced staining study has proven that one of the experimental AmF/SnF2 rinses leads to less staining than the other experimental AmF/SnF2 rinses. These experimental results have to be confirmed by further clinical investigations.