Novel in-situ longitudinal model for the study of dentifrices on dental erosion-abrasion.

A novel longitudinal erosion-abrasion in-situ model was proposed. In an exploratory test (phase 1) toothbrushing effect was investigated using a parallel design, whereas in the main study (phases 1 + 2), a crossover design tested the effect of fluoride dentifrice. In phase 1, 16 subjects (n = 5-6 subjects per group) wore partial dentures with enamel specimens for 28 d and adhered to one of the following treatment regimens: regimen A, erosion only; regimen B, erosion + toothbrushing with fluoride-containing dentifrice [1,100 ppm of fluoride as sodium fluoride (NaF)]; and regimen C, erosion + toothbrushing with placebo dentifrice (0 ppm fluoride). Erosion consisted of the exposure of specimens to grapefruit juice. In regimens B and C, toothbrushing was performed with the test dentifrices 5 min after erosion. For the main study a second phase was carried out in which subjects initially treated with regimen B were treated with regimen C, and vice versa (crossover, n = 11), repeating the same experimental protocol. Enamel wear was measured by optical profilometry at baseline and every 7 d thereafter. In the exploratory test (phase 1), no significant differences were observed among regimens at any of the study time-points. In the main study (phases 1 + 2), higher enamel wear was observed for regimen C than for regimen B. A significant trend was observed for the increase of enamel wear over time. Fluoridated dentifrice reduced the development of erosive-abrasive lesions. The proposed longitudinal model provided adequate responses for erosion-abrasion frequency and fluoride effects.

Development of labeled magnitude scales for the assessment of pain of dentin hypersensitivity.

AIMS: To develop and test labeled magnitude (LM) scales that are sensitive to variations in pain associated with dentin hypersensitivity (DH). METHODS: Qualitative methods were used first to obtain words that describe the pain of DH. Magnitude estimation was then used to determine the position of these descriptive terms by relative magnitude along four vertical LM scales. To assess their DH, patients used the four LM scales following dentin stimulation with 4°C and 25°C water. The LM scales were then compared to visual analog scale (VAS) ratings by using eight pain scenarios of varying severity. Finally, participants with DH completed the four horizontal LM scales and VAS after dentin stimulation with 4°C and 25°C water. Within-subject t tests were used for comparisons between scales and water temperatures, and between-subject t tests were used for comparisons between participants with and without DH. RESULTS: Participants showed comparable differentiation between 4°C and 25°C water on VAS and three of the LM scale measures. Responses on the fourth LM scale showed better differentiation than VAS between the two water temperatures. Participants used a greater portion of the LM scales than VAS when rating low-level pain scenarios. CONCLUSION: LM scales were shown to provide some advantages compared to standard VAS when used to evaluate DH-associated pain. These advantages may be generalized to other low-level pain conditions.

A comparative evaluation of the efficacy of two novel desensitising dentifrices.

A comparison of the desensitising efficacy of two commercially available dentifrices with different modes of action was conducted in a randomised, examiner-blind, two-arm, parallel group, 8-week, longitudinal clinical study. Dentifrice A, (Sensodyne Multi Action Iso-Active), contained 50000 ppm KNO(3) and 1450 ppm fluoride as NaF. Dentifrice B, Colgate Sensitive Pro-Relief, contained a combination of 80000 ppm arginine, bicarbonate, calcium carbonate, and 1450 ppm fluorine as NaMFP. Subjects (N = 110), stratified into two groups (N = 55), brushed twice-daily for 60 s, over an 8-week period. Sensitivity status, compliance, and safety were determined at 1, 2, 4, and 8 weeks. A fixed-effects ANCOVA statistical model was applied to the Intent-To-Treat population using a two-sided 5% significance level. After 8 weeks, the treatment groups using Dentifrice A and Dentifrice B exhibited mean reductions from baseline of 49% and 45% in air sensitivity visual analogue scale (VAS) score, 61% (both) in examiner-based Schiff Sensitivity score, and clinically significant reductions in tactile pain threshold; all reductions were statistically significant (P < 0.0001). Both treatment groups also exhibited significant reductions across all sensitivity measures at 1, 2, and 4 weeks (P ≤ 0.0059, Dentifrice A; P ≤ 0.0137, Dentifrice B).

Overview of the clinical evidence for the use of NovaMin in providing relief from the pain of dentin hypersensitivity.

Dentin hypersensitivity is a common condition that affects the adult population worldwide. NovaMin is technically described as amorphous sodium calcium phosphosilicate, and has been shown in laboratory studies to rapidly occlude dentin tubules and form a protective hydroxyapatite-like layer on the dentin surface. A number of clinical studies investigating the efficacy of NovaMin for the relief of pain from dentin hypersensitivity have been conducted in the United States, Ireland, China, and India. This article reviews the available literature and finds support based on randomized controlled clinical trials for the use of NovaMin in anhydrous toothpaste formulations in providing relief of pain from dentin hypersensitivity.

Construction and validation of the quality of life measure for dentine hypersensitivity (DHEQ).

AIM: To develop and validate a condition specific measure of oral health-related quality of life for dentine hypersensitivity (Dentine Hypersensitivity Experience Questionnaire, DHEQ). MATERIALS AND METHODS: Questionnaire construction used a multi-staged impact approach and an explicit theoretical model. Qualitative and quantitative development and validation included in-depth interviews, focus groups and cross-sectional questionnaire studies in a general population (n=160) and a clinical sample (n=108). RESULTS: An optimized DHEQ questionnaire containing 48 items has been developed to describe the pain, a scale to capture subjective impacts of dentine hypersensitivity, a global oral health rating and a scale to record effects on life overall. The impact scale had high values for internal reliability (nearly all item-total correlations >0.4 and Cronbach's α=0.86). Intra-class correlation coefficient for test-retest reliability was 0.92. The impact scale was strongly correlated to global oral health ratings and effects on life overall. These results were similar when DHEQ was validated in a clinical sample. CONCLUSIONS: DHEQ shows good psychometric properties in both a general population and clinical sample. Its use can further our understanding of the subjective impacts of dentine sensitivity.

Design and construction of a magnetic resonance compatible multi-injector gas jet delivery system.

We present the design, construction, and performance of a novel multi-injector gas jet delivery capable of operating in a magnetic resonance imaging environment. This apparatus is computer controlled and built with two separate pneumatic circuits enabling gas jet applications at variable sites through four independently activated injectors. Gas jet delivery is fully controllable in terms of pressure, flow rate, gas temperature, application time, and duration of interstimulus interval. We characterized these parameters, considering effects such as pressure drop by flow transport, transient effects, and delays in activation. The system offers new possibilities for use in various biomedical contexts such as, e.g., quantitative sensory testing or dental hypersensitivity assessment.

A novel oral hygiene system through integration of a sonic toothbrush and liquid toothpaste.

A novel system for home oral hygiene, the IntelliClean System from Sonicare and Crest is an integrated sonic toothbrush and liquid-toothpaste dispensing system. New research has established the ability of this system to reduce plaque, especially in interproximal regions, and to reduce gingivitis. The unique capability for the user to reapply liquid toothpaste during brushing (ie, re-dose) allows for a greater reduction in bacteria in the sulcus and an enhanced in-use experience that leads to improved compliance with brushing instruction, specifically longer brushing times. Through in vitro and in vivo studies, the system and its constituents have been shown to be safe for daily use.

Effect of a novel integrated power toothbrush and toothpaste oral hygiene system on gingivitis.

The purpose of this article is to compare the gingivitis reduction efficacy relative to baseline of an integrated power toothbrush/toothpaste dispensing system prototype, the IntelliClean System from Sonicare and Crest. This was a randomized, controlled, parallel-group, examiner-blind study that examined the gingivitis reduction efficacy of a novel integrated system compared to a positive control consisting of manual toothbrushing coupled with daily flossing over a 4-week period. Mean change from baseline for gingival index (GI) and bleeding scores were tested using paired t tests for each treatment group, separately. Between-group comparisons were made with respect to change from baseline using analysis of covariance. Baseline values were used as the covariate. All tests were 2-sided with a 0.05 level of significance. A total of 66 subjects (61 women and 5 men) completed the study. The subjects ranged in age from 20 to 64 years with an overall mean age of 39.4 years. Baseline GI and bleeding scores were not statistically significantly different (P > .2) between the experimental integrated system group and the positive-control group. Both treatment regimen groups demonstrated highly statistically significant reductions in GI and bleeding scores vs baseline (P < .0001) at weeks 2 and 4. After 4 weeks, there was a 28% mean reduction in GI for the experimental group and a 23% mean reduction for the positive-control group. Similarly, there was a 28% mean reduction in bleeding for the experimental integrated system group and a 23% reduction for the positive-control group. However, no statistically significant treatment difference was found between the 2 groups (P > .5) for either measure at week 2 or week 4. This study demonstrated the efficacy of the IntelliClean System from Sonicare and Crest in significantly reducing gingivitis and bleeding relative to baseline after 4 weeks of use according to the manufacturer's instructions.

Pharmacodynamic and pharmacokinetic effects in gingival crevicular fluid from re-dosing during brushing.

The IntelliClean System from Sonicare and Crest combines a rechargeable sonic power toothbrush and a novel liquid toothpaste into one integrated system, providing the opportunity to re-dose with toothpaste during the brushing cycle. The purpose of this study was to investigate cleaning effects from in-mouth re-dosing with toothpaste during the brushing cycle vs conventional bolus dosing. This was a randomized, examiner-blind, six-period, crossover clinical study. Eighteen adult subjects used an experimental integrated system employing either a re-dosing regimen (2 doses at the start of brushing with 1 additional in-mouth dose during the last 30 seconds of brushing [2+1]) or a conventional regimen (2 doses at the start of brushing only [2+0]). Gingival crevicular fluid (GCF) was sampled at the final brushing quadrant from a preselected site in the gingival sulcus using filter strips at baseline and at 4, 15, and 120 minutes postbrushing. Mean change from baseline in the concentrations of total facultative anaerobes (TFAs) and gram-negative anaerobes (GNAs) in the GCF at 120 minutes posttreatment were modeled separately using general linear mixed models. Area under the curve of surfactant (sodium dodecyl sulfate [SDS]) in GCF over 2 hours postbrushing was calculated and modeled using an analysis of variance model. All hypotheses were tested 2-sided at the 5% significance level. Relative to the conventional regimen, the re-dosing (2+1) regimen produced a significantly greater reduction in log10 (TFA colony-forming units [CFU]/microL GCF) after brushing, 0.99+/-0.12 vs 0.65+/-0.12 (mean change +/- standard error), and a significantly greater reduction in log10 (GNA CFU/microL GCF) after brushing, 0.75 +/-0.14 vs 0.45 +/- 0.14. The re-dosing regimen led to significantly more SDS in GCF relative to the conventional regimen over the 2-hour time period. Re-dosing of liquid toothpaste during the brushing cycle with the IntelliClean System leads to a significantly increased cleaning effect, as defined by a reduced bacterial count in GCF, and significantly higher levels of surfactant in the GCF up to 2 hours after the brushing event.

Delivery, substantivity and clinical response of a direct application percarbonate tooth whitening film.

PURPOSE: A novel overnight bleaching system containing 19% sodium percarbonate and silicone film forming agents (Crest Night Effects) is described, along with research supporting the substantivity of the product on tooth surfaces and its resulting whitening efficacy. METHODS: Nine adult volunteers were enrolled in a study to determine overnight retention (substantivity) of the product. A non-reactive blue pigment was added to the product to aid in evaluating retention. The participants applied the product to their anterior dentition at night and then had digital images taken. After 7 hours of sleep, the patients were awakened and re-imaged. The percent coverage with blue pigment on the surfaces of the 12 anterior teeth was calculated from the digital images after application and after awakening. The product was also evaluated in a 2-week efficacy study with 16 adult volunteers. Each night the participants brushed their teeth before going to bed as they normally would, dried their teeth with a towel, and then applied the product to their six maxillary and mandibular anterior teeth. The product was left on the teeth overnight and then removed in the morning via toothbrushing. Color (baseline and after 2 weeks of product usage) was determined using digital imaging and the standard L*a*b* measurement scale. RESULTS: In the substantivity study, 84.7% of the subject teeth surfaces were covered on average with the blue pigment-containing film immediately after application. Following overnight use, excellent retention was demonstrated as 77.4% of the initially covered surfaces still had pigment-containing film on them. These means did not differ significantly (P > 0.44). In the clinical efficacy study, there was significant (P < 0.0001) color improvement versus baseline after 2 weeks of treatment as measured by a mean (SD) delta b* of -1.71 (0.85) and mean (SD) delta L* of 1.62 (0.68). The product was well-tolerated, with the primary adverse events being oral irritation (13%) and tooth sensitivity (6%). No participants discontinued product use because of a product-related adverse event.

A clinical study to assess the breath protection efficacy of denture adhesive.

This randomized and controlled, examiner-blind, 3-period, crossover clinical trial was designed to determine the effect of an experimental denture adhesive, a marketed denture adhesive (European Fixodent( Fresh), or no denture adhesive on the breath odor of 37 adults wearing full maxillary and mandibular dentures. Breath quality was measured at baseline and at 3 and 6 hours after the start of each treatment period via monitoring of volatile sulfur compounds (VSCs) using a halimeter and second-person organoleptic grading. A 48-hour washout phase separated treatment periods. There were no statistically significant differences in VSCs between any of the treatment regimens over 6 hours. Both the denture adhesive treatments were superior in breath quality improvement in organoleptic scores compared to no denture adhesive at 3 and 6 hours (p=0.0001). This research demonstrates the ability of both an experimental and marketed denture adhesive to deliver superior second-person breath benefits relative to no adhesive. The results indicate that Fixodent denture adhesives provide the denture wearer with a noticeable improvement in breath.