Randomized in situ clinical study comparing the ability of two new desensitizing toothpaste technologies to occlude patent dentin tubules.

OBJECTIVE: To compare the ability of two new desensitizing toothpaste technologies (one a 5% NovaMin-based toothpaste and the other an 8% arginine-based toothpaste) to occlude patent dentin tubules in a clinical environment relative to a negative control of water and a control toothpaste after four days of twice-daily brushing and dietary acidic challenges. METHODS: The study design was a single-center, single-blind, randomized, split-mouth, four-treatment, two-period, crossover, in situ clinical study. Healthy subjects wore two lower intra-oral appliances, retaining four dentin samples for four treatment days for each period of the clinical study. Samples were brushed twice daily with a test product (days 1-4), with an additional acidic challenge introduced on two selective days. Scanning electron microscopy (SEM) images were taken of the dentin surface, and dentinal tubule occlusion assessed using a categorical scale. RESULTS: The results demonstrated that the 5% NovaMin toothpaste was statistically superior at occluding patent dentin tubules compared to water (p = 0.009) and the control toothpaste (p = 0.02) at day 4. In contrast, the treatment effect resulting from the 8% arginine toothpaste did not demonstrate the same degree of occlusive propensity, showing no significant difference to the water and control toothpaste at the day 4 time point. CONCLUSION: Application of the 5% NovaMin toothpaste to dentin showed better dentin tubule occlusion and retention abilities in an oral environment under dietary acid challenge conditions, more so than the 8% arginine toothpaste technology. Given modern dietary habits and practices, these results highlight differences in the acid resistance properties of occlusion technologies, and a potential impact on clinical performance.

Clinical in situ study investigating abrasive effects of two commercially available toothpastes.

The aim of this study was to determine if the abrasive effect on dentine of two commercially available toothpastes, known to vary in their in vitro abrasive levels, can be differentiated in an in situ model after 10 days, assessed by contact profilometry. This was a single centre, single blind, randomized, split mouth, two treatment, in situ study, in 34 healthy subjects, evaluating the abrasive effects of two marketed desensitizing toothpastes, (Colgate Sensitive Multi Protection toothpaste - C; Sensodyne Total Protection - S). Subjects wore bi-lateral, lower buccal appliances, each fitted with four dentine sections which were power brushed three times a day with the treatment regimen. Each subject received two toothpaste treatments for 10 days during the treatment period. Samples were measured at baseline and day 10 by contact and non-contact profilometry and day 5 by contact profilometry. Thirty-four subjects were included in the efficacy analysis. Results from contact profilometry showed statistically significant (P < 0.0001) dentine loss compared to baseline at day 5 and 10 for both pastes. At each time point, C showed statistically significantly greater dentine loss than S, P < 0.0001. After 10 days treatment, the difference in dentine loss between the pastes was 1.4 microm. The non-contact profilometry data showed similar trends. After 10 days of treatment, C showed statistically significantly greater dentine loss than S, with treatment difference of 0.9 microm, P = 0.0057. The methodology used has successfully differentiated between the abrasivity of the two pastes in respect of dentine surface loss over time in an in situ environment.

Development of an in situ methodology for the clinical evaluation of dentine hypersensitivity occlusion ingredients.

OBJECTIVE: The aim of these clinical studies was to evaluate an in situ dentine tubule occlusion model, and to determine the occluding effect from novel occluding agents on patent dentine tubules compared to a positive control (8% strontium acetate--Sensodyne Mint) and negative control (a non-occluding agent) after four days of brushing treatment. METHODS: These two in situ clinical studies were of single-center, randomized, crossover, single-blind design. Healthy participants wore two lower intra-oral appliances retaining four dentine samples for four treatment days for each period of the study. Samples were power-brushed each day with the test product. Assessment utilized surface topological analysis with a replica-based methodology under scanning electron microscopy (SEM). RESULTS: Both clinical trials demonstrated that the positive control (8% strontium acetate) occluded dentine tubules significantly better (p = 0.0007; p < 0.0009) than the negative controls in the two studies, respectively. The experimental occluding agents demonstrated varying degrees of success for occluding effect compared to the controls. CONCLUSION: The methodology clearly demonstrates that this in situ clinical model can robustly and reproducibly detect the dentine tubular occlusive effects of positive and negative controls in the treatment of dentine hypersensitivity brushed on the dentine surface. Using this methodology, new occlusion agents for the relief of dentine hypersensitivity can be assessed for occlusive effects on dentine.

Clinical research leadership-"A blueprint".

The principles of leadership in academic research, reflect those of life in general and differ only by circumstance. A great leader is one who inspires and energizes, motivating and empowering the whole team to achieve. They articulate a vision, establish direction, clarify the big picture and set clear strategies in a positive culture. A great leader needs to align and connect people by fostering excellent communication channels, gaining commitment and building teams and coalitions.

Prevalence of gingival recession and study of associated related factors in young UK adults.

OBJECTIVES: To determine the prevalence of gingival recession (GR) and associations with dentine hypersensitivity (DH), erosive toothwear (BEWE), gingival bleeding (BOP) and periodontal pocketing (PPD) in young European adults. MATERIALS AND METHODS: This is a secondary analysis using data collected from 350 UK participants enrolled in a European cross sectional study of 3187 young adults. GR, BOP, PPD, DH (participant and clinician assessment) and BEWE were recorded. A questionnaire assessed demographics, oral hygiene and lifestyle habits. RESULTS: 349 participants completed the study. GR, BOP and PPD showed the same pattern of distribution, prevalence increasing from incisors to molars in upper and lower arches for buccal and palatal scores. Every participant exhibited recession affecting at least 1 tooth, 42% having a maximum recession of 4-8 mm. There was a significant and linear association demonstrating an increase in maximum recession with age. DH and BEWE produced a similar pattern to buccal periodontal indices, the premolars being most affected. Maximum recession correlated significantly with maximum DH (participant and Schiff), PPD, BOP, BEWE (scores of 2/3), BMI (≥25 kg/m2) and unsystematic brushing motion. 94% of the study population exhibited some BOP at one or more sites. 5% of the population had periodontal pocketing ≥4 mm, 46% had DH and 80% BEWE 2/3. CONCLUSION: Widespread recession and gingivitis with minimal periodontal disease was observed. Every participant exhibited at least one tooth with recession. Many teeth did not exhibit DH despite prevalent recession and severe erosive toothwear. Recession correlates to a number of oral and lifestyle variables. CLINICAL SIGNIFICANCE: Recession in young adults is multifactorial and highly prevalent. It can result in DH and consequential increase in demand for treatment relating to both pain and aesthetics. Further research is needed to understand the underlying aetiology to prevent recession occurring.

A randomised clinical trial to determine the abrasive effect of the tongue on human enamel loss with and without a prior erosive challenge.

OBJECTIVES: To investigate the abrasive effect of the tongue on human enamel loss with and without a prior dietary acid challenge in an in situ model. METHODS: A single centre, single blind, randomly allocated, split mouth, four treatment regimen, in situ study in healthy adult volunteers was undertaken. Twenty four subjects wore two lower intra-oral appliances each fitted with 4 human enamel samples 6h/day for 15 days. The samples were treated with either 50ml orange juice or water for 5min ex vivo 4x/day; prior to being licked or not licked with the subject's tongue for 60s. There were 2 samples per group per subject. Surface loss was measured by contact profilometry. RESULTS: 23 subjects completed the study with no adverse events. The mean loss of enamel at 15days was: 0.08µm for water without licking, 0.10µm with water and licking; 1.55µm with orange juice alone, 3.65µm with orange juice and licking. In the absence of erosive challenge, licking had no detectable effect on enamel loss p=0.28. Without licking, orange juice had a highly significant effect on loss compared to water, p<0.001. Erosive challenge followed by licking more than doubled the loss of enamel p<0.001. CONCLUSIONS: When enamel was exposed to orange juice prior to licking, tissue loss as a result of tongue abrasion of the eroded surface was increased, and double that of the erosive challenge alone. Licking enamel with the tongue had no perceptible effect on enamel loss in the absence of the erosive challenge. CLINICAL SIGNIFICANCE: Enamel wear resulting from tongue abrasion on tooth surfaces softened by acid challenge, can be an unavoidable consequence of oral function. This may account for the pattern of erosive toothwear on palatal and occlusal tooth surfaces, reinforcing the importance of restricting the frequency of dietary acid challenge in susceptible individuals.

Clinical enamel surface changes following an intra-oral acidic challenge.

OBJECTIVES: Investigation of early enamel erosion using replica impressions to compare changes in enamel surface topography in vivo prior to and over a 24 h period following acid challenge. METHOD: A single treatment, blinded, enamel replica clinical study was undertaken in 20 healthy subjects. Replica tooth impressions were taken at baseline, following acid challenge and 2, 4, 7 and 24 h post challenge. Subjects consumed 500 ml of acidic soft drink over 30 min. Scanning electron microscopy of surface tomography was characterised with a descriptive 5 point scale by four judges. Duplicate impressions were taken to assess reproducibility. RESULTS: 18 subjects had scorable sequences. Descriptive analyses showed erosive changes following acid consumption and reparative changes in the subsequent 24 h period. Comparing baseline replica to the 24 h replica, there were no significant differences (p=0.26) in tooth surface characteristics. Comparing the replica taken immediately following acidic challenge with the subsequent replicas at 2, 4, 7 and 24 h, showed clear reduction of erosive effects on the enamel surface at 2 h (p=0.02) and a highly significant reduction at 4, 7 and 24 h (p<0.001). CONCLUSION: This methodology demonstrated the ability to follow the progression and recovery of early erosive enamel lesions over 24 h being accurate and reproducible. This study suggests enamel repair commences within 2 h following a substantial acidic challenge and is completed 4-24 h later. After 24 h, the tooth surface appeared visibly indistinguishable from the original tooth surface, suggestive of a recovery process occurring. CLINICAL SIGNIFICANCE: Healthy erosive lifestyles often culminate in tooth wear. The time taken for enamel remineralisation following acidic challenge is unknown however, this study suggests the repair process is relatively slow following a substantial acidic challenge, and at least 4-24 h should elapse prior to further acidic consumption to allow for recovery.

The CaATPase activity of rat-incisor odontoblast vesicles.

An homogenate of rat incisor odontoblasts had Ca2+ and Mg2+ ATPase activity and suitable storage conditions kept it stable for several days. Over 90 per cent of the activity was retained in a vesicle-rich microsomal fraction that removed about 85 per cent of the total material from the homogenate. This fraction was further characterized: the resolved Ca2+-activated ATPase activity, above the basal MgATPase activity, was 0.30 mumol Pi/min-mg total protein, and 50 per cent activated at free [Ca2+] equal 0.8 microM. This calcium dependency is consistent with an intracellular Ca2+-regulated enzymatic activity. The calcium ionophore, A23187, had no measurable effect on the CaATPase activity, which suggests that the odontoblast vesicles do not concentrate Ca2+ in a lipid bilayer compartment. Direct measurement of the uptake of 45Ca2+ by the filtration method and parallel measurements of CaATPase activity on the same preparations under identical conditions indicated that the odontoblast-derived vesicles have a coupling ratio of 0.024 Ca2+/ATP. This low coupling ratio and the lack of detectable compartmentalization of calcium indicate that the CaATPase activity of the odontoblast microsomes is not associated with a calcium pump. The [Ca2+] dependence of the activity suggests the CaATPase is under intracellular Ca2+ control, but its function is unknown.

A 3-day randomised clinical study investigating the efficacy of two toothpastes, designed to occlude dentine tubules, for the treatment of dentine hypersensitivity.

OBJECTIVES: A product comparison study to compare the short term clinical efficacy of a strontium acetate/silica toothpaste with an arginine/calcium carbonate paste for pain reduction in dentine hypersensitivity. METHODS: The study was examiner blind of two arm parallel design. Eighty healthy adult subjects from general dental practice with ≥2 sensitive teeth but otherwise good oral health, were enrolled and randomised to 1 of 2 toothpaste treatments, schedule provided by the sponsor. Almost equal numbers received each treatment. Tooth sensitivity was measured in three ways; evaporative (Schiff score; Visual Analogue Scale) and tactile stimuli (Yeaple probe), prior to and immediately after subjects' self application of a single pea sized dose of toothpaste, and following subsequent twice daily brushing for three days with the paste. RESULTS: All 80 subjects completed the study. Results confirm that for both treatments, pain was reduced immediately and relief was sustained after 3 days use. For all 3 measures, benefit was similar between the two pastes, with no statistical or clinical difference demonstrated, apart from response to evaporative stimulus at 3 days, where Schiff scores were significantly lower in the arginine group, p=0.02. CONCLUSIONS: It can be concluded that both desensitising, occluding toothpastes provided reduction of pain from dentine hypersensitivity on a short term basis: toothpastes appearing to be clinically similarly effective both after a single subject dab on application and post twice daily brushing for three days. National Research Ethics Service register number 09/H020/57.

In situ randomised trial investigating abrasive effects of two desensitising toothpastes on dentine with acidic challenge prior to brushing.

OBJECTIVES: To determine if brushing dentine with 2 moderate RDA desensitising toothpastes, results in a significant dentine wear difference and whether this difference continues to be relevant when preceded with an erosive challenge. METHODS: An in situ, single centre, single blind, randomised, split mouth study, evaluated the difference in abrasion of 2 toothpastes (SFM - Sensodyne Fresh Mint(®) RDA 70; CPHM - Crest Pro-Health Clean Mint(®) RDA 120) in 28 healthy volunteers. Two toothpaste treatments were administered 3×/day, for each of the two 15 day periods, subjects wearing bi-lateral, lower buccal appliances each with 4 dentine sections. A 2 min extra-oral acidic challenge preceded toothbrushing for 2 study arms. Contact profilometry measured samples at baseline, days 5, 10 and 15. RESULTS: Brushing with SFM was significantly less abrasive than brushing with CPHM at all time points, with or without a preceding acidic challenge (p<0.0001). The additional dentine loss arising from the erosive challenge prior to brushing with each paste was linear with time and independent of abrasive effect. CONCLUSIONS: The desensiting toothpastes' RDA, directly related to dentine loss with toothbrushing. An acidic challenge prior to brushing did not negate the benefits of reduced wear from the lower RDA paste compared to the higher RDA paste. When brushing eroded dentine, the additional wear appeared independent of abrasive effect. Dentine hypersensitivity sufferers should be recommended to use a low-moderate RDA toothpaste, not to brush more than 2×/day and not immediately following an acidic challenge.

A comparison of two chlorhexidine gel brushing regimens and a conventional toothpaste brushing regimen for the development of tooth staining over a 6-week period.

AIMS: A single-centre, randomized single-blind parallel study was undertaken to compare staining seen with three brushing regimens and to determine subject perception of side effects such as staining and effects on taste. METHODS: This 6-week parallel study used 157 volunteers who were randomized into one of three treatment groups: (i) brushing in the morning and evening with a normal dose of a 1% chlorhexidine gel, (ii) brushing with a low dose of chlorhexidine gel in the evening and a whitening dentifrice in the morning, and (iii) brushing with a standard fluoride paste in the morning and evening. Following home usage of their allocated products, the study volunteers returned after 3 and 6 weeks to record the amount of stain present. After the 6-week period, subject perception of taste and stain acceptability was determined using a questionnaire. RESULTS: After 6 weeks of use of the low-dose chlorhexidine gel and whitening dentifrice, significantly more stain was seen compared with the use of a standard dentifrice (P<0.0001). Similarly, significantly more stain was seen with use of the normal-dose chlorhexidine gel compared with the low-dose gel and whitening dentifrice (P=0.0007). Approximately 30% of individuals on the low-dose chlorhexidine gel regimen found the amount of stain unacceptable and 10% noted an effect on their taste perception. CONCLUSIONS: The use of low dose of chlorhexidine gel at night and a whitening paste in the morning produced a significant amount of stain that 30% of subjects considered unacceptable.

The prevention of plaque re-growth by toothpastes and solutions containing block copolymers with and without polypeptide.

BACKGROUND/AIMS: Chemicals which have a direct effect at inhibiting or reducing bacterial adherence to tooth surfaces may subsequently inhibit plaque growth and reduce gingival inflammation. This study investigated whether two anti-adherent systems could inhibit plaque re-growth in the mouth when rinsed as a solution or as a toothpaste slurry. METHODS: A total of 21 subjects took part in a partially blind, seven cell cross-over study which compared the effects on plaque re-growth of a binary system containing block copolymers, a ternary system containing block copolymers and polypeptide, both used as toothpaste slurry rinses, their corresponding solution rinses, a conventional fluoride toothpaste rinse, a positive control chlorhexidine rinse and a negative water control. Following a dental prophylaxis subjects then rinsed with 10 ml of one of the test products for 1 min. twice a day over a 4-day period. Throughout each trial period the subjects were not permitted to use any other forms of oral hygiene. On the fifth day (96 h), the volunteers returned to the clinic, and plaque was assessed by (1) plaque index and (2) plaque area following disclosing with a food dye. The test phase of the trial was repeated for each agent and was followed by a 10-day "washout" period. RESULTS: Essentially neither of the anti-adherent systems inhibited plaque re-growth, whether administered in a toothpaste slurry or solution compared with the controls. If anything, neither of the test pastes were as effective as the marketed commercial paste (p<0.001). As expected plaque recorded following use of the chlorhexidine rinse was significantly less than that seen with any of the other rinses (p<0.001). CONCLUSIONS: Using this 4-day plaque re-growth model, the findings of this study failed to show any benefit in using the anti-adherent systems, either in a rinse or toothpaste, with the aim of inhibiting or reducing plaque formation.

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

AIMS: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

The use of plaque area and plaque index to measure the effect of fluoride and chlorhexidine toothpastes on 24-h plaque regrowth.

Short-term methodologies have been developed to screen chemical agents for plaque inhibitory effects. Most measure inhibition of plaque regrowth over several days. A method was described to study agents over 16-24 h periods, although some difficulties with the index used were reported. The aim of this study was to determine whether more conventional plaque scoring methods could be used. These 2 crossover studies measured plaque regrowth over 24 h in 20 subjects and in response to single brushings with either a chlorhexidine and minus active toothpaste or to a fluoride toothpaste product and water. Significantly less plaque had reformed after brushing with the chlorhexidine toothpaste compared with its control and with the fluoride toothpaste compared with water. 18 subjects participated in both studies and using their data for an interstudy comparison, less plaque developed with the chlorhexidine compared with the fluoride toothpaste. These studies had the advantage that longer-term trials already demonstrated the same differences. This permits one to conclude with some certainty that the 24-h plaque regrowth study design, using conventional measures of plaque accumulation, could be a useful and rapid method of screening potential plaque inhibitory agents and formulations.

The use of planimetry to record and score the modified Navy index and other area-based plaque indices. A comparative toothbrush study.

Many plaque-scoring methods are based on a subjective assessment of the amount of tooth surface covered by plaque or the presence or absence of plaque at specific sites. The 2x modified Navy plaque index is an example of the latter and requires chairside decisions from 9 zones of all buccal and lingual tooth surfaces, i.e., up to 576 for a complete dentition. The present study describes a procedural modification to the index, whereby plaque is recorded using an established planimetric plaque area method. Scoring is then performed using an overlay away from the clinic. To test the method, plaque-area measurements were made during a 30-subject, crossover study to compare plaque removal following single toothbrushings with 3 different types of manual toothbrush. Consistent with many such studies, no significant differences in plaque removal were noted between the brushes. The method was found quick and simple at the chairside, provided a permanent record of plaque distribution and could be analysed by clinical or nonclinical personnel under ideal conditions. The same method could be employed for other plaque indices based on area or site subjective decisions.

Comparative single-use plaque removal by toothbrushes of different designs.

Overall literature reviews have concluded that no one design of the manual toothbrush is superior for plaque removal. More recently, a toothbrush with filaments angled away from the head was shown to be more effective in several single-use studies than conventional designs. The aim of this study was to compare plaque removal by this new toothbrush and 3 other toothbrushes which had more conventional filament arrangements. 36 volunteers participated in this single-blind, randomised, 4-cell, crossover single use toothbrushing study. On day 1 of each period, volunteers brushed with a standard toothbrush and toothpaste for 60 s and then suspended oral hygiene for 48 h. On day 3, volunteers were scored for plaque by area and then brushed with the allocated test toothbrush with toothpaste for 60 s and plaque area was rescored. A washout of 4 days was allowed between test periods. The plaque areas were used to record the binary scores of the Rustogi et al. modification of the modified Navy plaque index but away from the clinic employing the Claydon and Addy procedural method for the index. Plaque removal scored by area and site were not significantly different between the brushes. This study is at variance with previous similar investigations which suggested that the new design of toothbrush head was superior for plaque removal. It is concluded again that there are no data which demonstrate unequivocally that any one manual toothbrush design is superior to any other for plaque removal.

A 24-h regrowth study to evaluate the plaque inhibitory properties of a proprietary liquid dentifrice.

Dentifrices have typically been formulated as pastes. Recently however, a number of liquid products have become available. The chemical plaque inhibitory activity of such products has so far received little attention. The aim of this study was to determine the plaque inhibitory effect of a proprietary liquid dentifrice by comparison to a negative control (water) and a conventional fluoride toothpaste. The study design was a randomised single centre, single blind 3-way cross-over trial with the objective of validating claims of plaque inhibition for the liquid dentifrice. Volunteers were rendered plaque free then asked to brush for one minute with one of the three test products, following which they abstained from oral hygiene for the subsequent 24 h. The plaque area was recorded and then measured planimetrically. The results showed that more plaque accumulated with water and the liquid dentifrice compared with the fluoride toothpaste. Thus, there was a statistically significant difference between the fluoride toothpaste and water and between the fluoride toothpaste and the liquid dentifrice. There was no significant difference between the liquid dentifrice and water. It is concluded that in this particular model system, the liquid dentifrice provided little chemical plaque inhibitory action.

An evaluation of an antiadhesive copolymer agent on plaque inhibition by chlorhexidine.

The high molecular weight copolymer M239144 has proven antiadhesive action in vitro but clinically lacked effect, even when combined with chlorhexidine. This latter result was thought to arise from inactivation of chlorhexidine by the copolymer. The aim of this study was to determine whether improved activity might arise if the copolymer and chlorhexidine were applied sequentially rather than combined. The study was a double-blind, randomised crossover design balanced for carryover using a 24-h plaque regrowth method. 2 groups of 25 subjects from a zero plaque baseline rinsed 1x with 15 ml volumes of the allocated paired rinses for 60 s. Subjects abstained from toothcleaning for 24 h and were scored for plaque by area. The paired regimens were: 1. placebo: placebo; 2. placebo: 0.03% chlorhexidine; 3. 1% co-polymer and 0.03% chlorhexidine; 4. placebo: 1% co-polymer; 5. placebo: 0.12% chlorhexidine. Plaque regrowth was greatest with regimen 1 and least with regimen 5. However, regimens 3 and 4 were not significantly different from regimen 1, whereas regimen 2 was significantly more effective than regimen 3. The results indicate that the copolymer alone is ineffective, and even delivered sequentially, inactivates chlorhexidine.

Comparison of a double-textured prototype manual toothbrush with 3 branded products. A professional brushing study.

BACKGROUND: The consensus has been that there is no one superior design of manual toothbrush for plaque removal, despite, in some cases, encouraging findings from laboratory studies. The user appears the major variable and may mask differences in brush efficacy. AIMS: The aim of this study was to compare 2 new double-filament texture brushes with 3 established brands for plaque removal, under standardised conditions of professional brushing. METHOD: The study was a blind, randomised crossover design, balanced for residual effects. A panel of 15 subjects suspended tooth cleaning for 3 days. On day 4, plaque was scored from 6 sites per tooth before and after a 2-min professional toothbrushing. A washout period of at least 3 days was allowed between study periods. RESULTS: Overall plaque removal was 50% with no significant differences between brushes, a 3% absolute difference in average total mouth plaque separating brushes. However, at upper- and mid-buccal sites, a not significant 8% and a significant 9% difference, respectively, in plaque removal were recorded in favour of one of the prototype brushes, and at the mid-lingual site, there was a non-significant 10% difference in favour of one branded brush. Other sites were cleaned similarly by all brushes except for reduced plaque removal from buccal compared to lingual surfaces and interproximal compared to mid-surface sites. Highly significant subject differences in plaque removal were noted which may be relevant to inherent anatomical difficulties in tooth cleaning for some individuals. Period effects were not significant, supporting the consistency in brushing by the professional brusher. CONCLUSION: The method appeared capable of detecting small benefits of brush design. However, the benefits reported must be taken within the context of an overall lack of difference between brushes. The method could be used to set and record a minimum level of efficacy for toothbrushes.

The use of professional brushing to compare 3 toothbrushes for plaque removal from individuals with gingival recession.

BACKGROUND: Toothbrush filament configuration now varies considerably, usually with the intention of improving plaque removal overall or from specific sites. AIMS: The aim of the study was to compare 2 branded toothbrushes with a brush designed with a convex filament head arrangement to improve plaque removal from teeth with buccal gingival recession. METHODS: The study was a randomised, 3-treatment, double-blind crossover design balanced for residual effects and involving 18 healthy volunteers. On day 1, subjects suspended toothcleaning and returned to the clinic on day 4. Plaque was scored by area and index before and after 2 min of toothbrushing with the allocated brush. Brushing was performed by a hygienist allocating a timed 15 s to each of the 8 buccal and lingual quadrants. 3 days was allowed between treatment periods. RESULTS: Plaque accumulation differed considerably by site as did plaque removal. Overall plaque removal was 40%. Analysis showed significant subject differences but, no significant period or treatment differences. CONCLUSIONS: Consistent with other reports, it must be concluded that brush design is not a major variable in plaque removal. However using this "robot"-like model, the dentition of some individuals and specific dental surfaces are inherently more difficult to clean than others.