Whitening Toothpaste Research Articles

In vitro cleaning, abrasion and fluoride efficacy of a new silica based whitening toothpaste containing blue covarine

Objectives To investigate the stain removal ability, abrasivity towards enamel and dentine, and fluoride efficacy of a new silica based blue covarine whitening toothpaste in vitro. Methods Stain removal was assessed by brushing artificially stained bovine specimens with slurries of either the new toothpaste or one of two whitening products or a non-whitening silica product. Toothpaste abrasivity was assessed by brushing enamel/dentine specimens with slurries of either the new toothpaste, a whitening toothpaste or a non-whitening toothpaste and measuring the wear via a combination of changes in geometry of Knoop indents and surface profilometry. Fluoride efficacy was assessed using remineralisation, demineralisation and fluoride-uptake methods. Results The in vitro cleaning study showed that the silica based blue covarine whitening toothpaste removed significantly ( p < 0.05) more stain than the non-whitening toothpaste and was as effective as the two marketed silica based whitening toothpastes. This enhanced tooth whitening benefit did not give rise to a concomitant statistically significant increase in the level of wear to enamel and dentine compared to the non-whitening silica based toothpaste. The fluoride efficacy was superior to a non-fluoridated control and was as effective as a clinically tested formulation containing the same fluoride source. Conclusions The studies show that the new whitening toothpaste is effective in extrinsic stain removal, does not have an undue degree of abrasivity to enamel or dentine compared to other relevant commercially available products, and is an efficacious source of fluoride.

Evaluation of a new silica whitening toothpaste containing blue covarine on the colour of anterior restoration materials in vitro

Objectives The aims of this study were to evaluate the effects of a novel silica-based blue covarine whitening toothpaste on the colour of anterior restoration materials. Methods Restoration materials (three glass ionomers, three resin composites) were cast into disks (10 mm diameter, 2 mm thick) using cylindrical moulds. Specimens were immersed in pooled whole saliva prior to exposure to staining materials via one of two protocols. CIELAB colour measurements were taken at baseline and after each stage of the procedures. In one protocol, specimens were brushed with 10 ml of 33% (w/w) silica whitening toothpaste containing blue covarine slurry in water four times, for 10 min each time, with control specimens being immersed in water or red wine for the same period. Disks were re-immersed in saliva for 2 h between cycles. In the other protocol, specimens were immersed in 20 ml of water, red wine or silica whitening toothpaste containing blue covarine slurry for 96 h with colour measurements being taken afterwards. The second protocol disks were then brushed for 2 min using a non-whitening silica paste and further colour measurements made. Colour differences were then calculated. Results At the end of both protocols the disks treated with silica whitening toothpaste containing blue covarine were not significantly different from the water controls ( p > 0.1) in contrast to those treated with red wine. Even prior to brushing in the second protocol, there was no significant staining from the new toothpaste compared to the water control ( p > 0.1). Conclusions There was no significant staining by the silica whitening toothpaste containing blue covarine on any of these materials.

Instant tooth whitening from a silica toothpaste containing blue covarine

Objective To measure the instant whitening effect delivered immediately after brushing with a novel silica whitening toothpaste containing blue covarine. Methods A controlled, single blind, cross-over study was performed to compare the tooth colour measured in a group of subjects at baseline and immediately after brushing with a silica whitening toothpaste containing blue covarine versus a clear gel negative control toothpaste. Measurements of tooth colour were made using a mobile non-contact camera-based digital imaging system and expressed as CIELAB and WIO whiteness index. Results Analysis of covariance (ANCOVA) showed that the silica whitening toothpaste containing blue covarine was significantly more effective than the negative control toothpaste ( p < 0.05), and made teeth measurably less yellow, less red and overall whiter immediately after brushing. Conclusion A statistically significant reduction in tooth yellowness and improvement in tooth whiteness was measured immediately after brushing with a novel whitening toothpaste containing blue covarine.

Review of the extrinsic stain removal and enamel/dentine abrasion by a calcium carbonate and perlite containing whitening toothpaste

There has been an increase in the demand from consumers and patients for products that whiten teeth. To meet this demand, a whitening toothpaste containing calcium carbonate and perlite as the abrasive system and an efficacious fluoride source has recently been launched. The aim of the current paper is to review the toothpaste's stain removal efficacy and its effects on enamel and dentine wear. It has been shown to be effective at removing model extrinsic stain in vitro. Further, it has been shown to be more effective in removing naturally occurring extrinsic tooth stain than a silica non-whitening control toothpaste after two weeks of twice daily brushing in a parallel group, double-blind clinical study using 152 adult volunteers. In addition, the enhanced whitening effect did not give a clinically relevant level of wear to enamel or a significant increase in dentine wear compared to marketed non-whitening toothpaste formulations, as shown by using an in situ type model with ex vivo brushing.

In vitro efficacy of a whitening toothpastecontaining calcium carbonate and perlite

The studies described in this paper aimed to assess the stain removal efficacy, fluoride efficacy and abrasivity to enamel and dentine of a new whitening toothpaste containing calcium carbonate and perlite, using appropriate in vitro models. Stain removal efficacy was assessed using the pellicle cleaning ratio (PCR) method. Fluoride efficacy was assessed using remineralisation, demineralisation and fluoride-uptake methods. Abrasivity was assessed using an enamel and dentine wear method. The results showed that the new whitening toothpaste was able to remove extrinsic tooth stain more effectively than three commercially available toothpaste formulations. The fluoride efficacy was superior to a non-fluoridated control and was not significantly different to a clinically tested fluoride-containing toothpaste. The abrasivity data showed that the calcium carbonate/perlite toothpaste is no more abrasive to enamel or dentine than two other commercially available whitening toothpastes. The studies show that the new whitening toothpaste is effective in extrinsic stain removal, has an efficacious fluoride source and does not have an undue degree of abrasivity to enamel or dentine compared to other relevant commercially available products.

The measurement of enamel and dentine abrasion by tooth whitening products using an in situ model

To determine the enamel and dentine wear of two whitening toothpastes using an in situ model with ex vivo brushing. Human enamel/dentine (approximately 50:50) blocks (approximately 4 x 4mm) were placed in the upper buccal aspects of full or partial dentures of a group of 25 subjects. Subjects brushed the specimens ex vivo with either a calcium carbonate/perlite or silica containing whitening toothpaste under exaggerated conditions as compared to normal for 30 s, twice per day. Specimens were removed after 4, 8 and 12 weeks and the wear to the enamel and dentine was determined. Enamel wear was determined by change in Knoop indent length and dentine wear was determined from the enamel-dentine step height, measured using optical profilometry. The mean wear after 12 weeks was for enamel 0.27 and 0.19 microns, and for dentine 34.3 and 61.1 microns, for the calcium carbonate/perlite and silica toothpastes respectively. There were no significant differences between products after 12 weeks. The rate of wear was found to decrease throughout the duration of the study. There were no significant differences between the two whitening toothpastes in terms of enamel and dentine wear after 12 weeks brushing.

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

Two single centre, randomized single-blind, crossover studies were performed, to compare the effect of a test toothpaste with a conventional fluoride paste in the inhibition and removal of extrinsic dental stain promoted by repeated chlorhexidine/tea rinses. These studies used 24 subjects in each of two separate clinical trials. On the Friday before each trial period, the subjects received a prophylaxis to remove all staining, plaque and calculus deposits. On the following Monday, subjects were checked whether they were stain free and then under direct supervision they rinsed with a 0.2% chlorhexidine mouthrinse, immediately followed by a rinse with a warm black tea solution. This cycle was repeated hourly eight times throughout the day and on the following days until the Friday. In addition subjects also received daily a single toothpaste slurry rinse or control water rinse in the morning and lunchtime. No other form of oral hygiene was permitted during this period. On the Friday, both stain area and intensity was assessed using the Lobene Stain Index. For the stain removal study, stain was promoted again using chlorhexidine and tea rinses. After 4 days, stain was measured both prior to and immediately after brushing with the allocated toothpaste for 2 min. Subjects were then instructed to use the toothbrush at home according to their normal oral hygiene practices. On the following Wednesday, the amount of stain present was re-assessed. Each subject subsequently received a thorough prophylaxis to remove all plaque calculus and staining before starting the following periods of the study. The study showed no difference in the ability of the test whitening toothpaste, control toothpaste and water control at inhibiting stain. There was also only a small difference (3.5% for product of area and intensity) between the ability of the two toothpastes to help remove stain after a single brushing. The difference was however in favour of the test product which approached a conventional level of significance (P = 0.089). There was no evidence of superiority for either of the pastes after normal home usage. This study has suggested that the test product may have some advantage over the conventional paste at removing stain but the magnitude of difference would appear to be small and of little clinical relevance.

Clinical study to compare the effectiveness of a test whitening toothpaste with a commercial whitening toothpaste at inhibiting dental stain

A single centre, randomised single-blind, three-way crossover study was performed, to compare the effect of an experimental test toothpaste with a commercially available whitening toothpaste and water control at inhibiting extrinsic stain promoted by repeated chlorhexidine/tea rinses. This study used 23 subjects. During the week before the study the subjects received a prophylaxis to remove all staining, plaque and calculus deposits. On the Monday of the following week subjects returned to the clinic to receive their rinses and to check their dentition was stain free. Under direct supervision at both 09:00 and 13:00 hours they rinsed with either a toothpaste slurry or water control that was repeated daily up to and including the following Thursday. Additionally from the Monday to the Thursday each subject rinsed with a 0.2% chlorhexidine mouthrinse, immediately followed by a rinse with a warm black tea solution. This cycle was repeated hourly eight times throughout the day and on the following days until the Friday. Throughout this period volunteers omitted all other forms of oral hygiene except rinsing with the chlorhexidine mouthwash. On the Friday the level of stain on the teeth and dorsum of tongue was assessed using the Lobene stain index for both stain area and intensity. At the end of each trial period each subject received a thorough prophylaxis to remove all plaque, calculus and staining before starting the second and third period of the study. As expected appreciable amounts of extrinsic stain accumulated on the teeth over each study period. The amount of stain following use of the toothpastes and water control was least with the experimental toothpaste, followed by water control and lastly the commercial whitening paste. For all sites combined there was evidence that the experimental paste was significantly superior to both the commercial paste and water control at reducing stain area (p<0.001), a product of stain area and intensity (p<0.001 and 0.05, respectively) but not stain intensity (p>0.05). In this stain-prevention model the use of an experimental paste showed a significant reduction in stain accumulation on the teeth compared with a (placebo) negative water control and a commercially available whitening paste. As such the experimental paste would be expected to be of benefit in controlling extrinsic dental staining.

Effect of toothpaste with natural calcium carbonate/perlite on extrinsic tooth stain

The current study was designed to determine the effect of natural calcium carbonate toothpaste containing Perlite and microgranules (Whitening toothpaste) on extrinsic tooth stain compared to a standard commercial toothpaste formulation with precipitated calcium carbonate (PCC) as abrasive and a commercial toothpaste with dicalcium phosphate dihydrate (DCPD) as abrasive. The toothpastes were evaluated in a double blind, three-cell, stratified (tobacco use; baseline tooth stain level), parallel group design study involving 600 subjects with extrinsic tooth stain. Subjects brushed twice daily with their allocated toothpaste for four weeks. Extrinsic tooth stain was measured using the Macpherson modification of the Lobene stain index. ANCOVA showed significant differences between toothpastes (p=0.037). Subsequent multiple comparisons using pairwise t-tests, showed the Whitening toothpaste to be superior to the DCPD toothpaste (p=0.014) and the PCC toothpaste (p=0.067). When a Box-Cox transformation was made to the data (y0.6) to improve normality, these two differences were more accurately estimated at p=0.004 and p=0.03 respectively. The Whitening toothpaste has been shown to be significantly more effective in tooth stain removal than the two standard commercial toothpaste formulations.

An in situ Investigation into the Abrasion of Eroded Dental Hard Tissues by a Whitening Dentifrice

This crossover study aimed to investigate abrasion of previously eroded hard dental tissues by a whitening dentifrice compared to a regular dentifrice. After a 3-day lead-in period, 14 volunteers were randomly assigned to use one of the toothpastes while wearing a removable appliance, containing 3 enamel and 3 root dentine slabs on each side. On the first day salivary pellicle was allowed to form. Twice daily for the following 3 days, one side of each appliance was immersed in an acidic carbonated drink ex vivo while the other side remained unexposed. Specimens were then brushed with the allocated dentifrice. After a 3-day washout period, new sets of enamel and dentine slabs were mounted in the appliances and the participants commenced period 2 using the alternative toothpaste. Acid-treated specimens always showed more wear than untreated specimens. The whitening dentifrice did not significantly increase the wear of softened enamel compared with the regular dentifrice. Brushing with the whitening toothpaste led to significantly greater wear of sound enamel and of both eroded and sound dentine than the regular dentifrice. The results suggest that whitening dentifrices may not increase the wear of acid-softened enamel but may have a more deleterious effect on dentine than regular toothpastes.

Whitening toothpastes: effects on tooth stain and enamel

Objectives : To compare the stain removal and prevention efficacy of a whitening toothpaste (White System) and a standard silica toothpaste and to determine if any increase in tooth whitening benefits caused an increase in enamel abrasive wear. Methods : The products were evaluated in a laboratory-cleaning test and in a clinical study evaluating the removal and prevention of natural extrinsic stain over a four-week period. Enamel abrasive wear was determined using an in situ model where enamel blocks were placed on a denture worn in the mouth for four weeks and brushed twice daily. Results : The White System gave a statistically ( p <0.001) higher level of in vitro stain removal as compared to the standard silica toothpaste. The White System was significantly superior to the standard silica toothpaste in the clinical study in terms of extrinsic stain removal ( p <0.03) and prevention ( p <0.02). The product difference in the in situ enamel wear for these two toothpastes was not of statistical significance. Conclusions : The White System toothpaste was shown to be more effective in stain removal and prevention than a standard silica toothpaste. These enhanced tooth-whitening benefits did not give rise to a concomitant statistically significant increase in the level of wear to enamel.

In vitro chemical stain removal by 'whitening' toothpastes

This paper: Background A considerable number of toothpastes are available as tooth whitening products. Most appear to contain ingredients that might remove extrinsic stains rather than change natural tooth colour. Extrinsic stain removal could be achieved by physical or chemical means. Aim The purpose of this study was to measure the chemical stain removal properties of a range of whitening toothpaste products and experimental formulations using a standardised method in vitro. Materials and method 5 separate studies were conducted involving a total of 39 agents of which 28 were whitening products, 7 were experimental formulations, 2 were oxidising mouthrinses used as positive controls, 1 was a popular fluoride toothpaste product as a benchmark control, and 1 was water as the negative control. The formulations and controls varied in each study. The stain model was saliva/chlorhexidine/tea stain developed on optically clear acrylic to an optical density of at least 2.0. Groups of stained specimens were exposed to standard slurries or solutions of each test agent for 1 minute periods up to 5 minutes. Optical density readings were taken at each 1 minute time point. Analyses were based on per cent stain remaining after 5 minutes and time to 75% stain remaining. Results 3 toothpaste products achieved 100% stain removal by 5 minutes; 2 of these in 3 out of 4 studies in which they were used. 4 experimental formulations also achieved 100% stain removal. In general agents with high total stain removal also had short times to 75% stain remaining. The majority of agents tested had low total chemical stain removal and prolonged times to 75% stain remaining. A few agents were little different from water and several similar in effect to the conventional fluoride toothpaste. This method in vitro tests agents under the best case scenario conditions for chemical stain removal. Conclusion Only a small number of the whitening toothpaste products have good chemical stain removal potential; the majority are unlikely to achieve their claimed benefits through chemical stain removal. There is clearly a need for further data on the actual effects of such products using both methods in vitro and particularly in vivo or in situ.