Relationship between the plaque removal efficacy of a manual toothbrush and brushing force

Cervical wear pathobiology by robot-simulated 3-year toothbrushing - New methodological approach

OBJECTIVES

An ex-vivo study was aimed at (i) programming clinically validated robot three-year random toothbrushing, (ii) evaluating cervical macro- and microwear patterns on all tooth groups of different functional age, (iii) documenting and codificating wear related morphological features at the cemento-enamel junction in young teeth and on roots in older teeth.

DESIGN

Following ethical approval random toothbrushing (44 strokes per tooth horizontally, rotating, vertically; 2x/d) with manual toothbrushes and low-abrasive dentifrice was performed in an artificial oral cavity with brushing-force 3.5 N on 14 extracted human teeth. Morphological features were examined by SEM at baseline and after simulated 3 years using the replication technique. 3D-SEM analyses were carried out with a four-quadrant back scattered electron detector. Wilcoxon-Mann-Whitney-test was used for statistical analyses.

RESULTS

3-year random toothbrushing with horizontal, rotating and vertical brushing movements revealed morphological features classified as four enamel patterns, one dentin pattern and three cervical patterns. Negative impacts were enamel, cementum and dentin loss. Positive impact on oral health was removing dental calculus and straightening cervical traumatic and iatrogenic damages. The volume loss varied from x̅=34.25nl to x̅=87.75nl. Wear extended apically from 100 to 1500 micrometres.

CONCLUSION

Robot simulated toothbrushing in an artificial oral cavity, with subsequent SEM and 3D-SEM assessment, elucidated both negative and oral health-contributing micromorphology patterns of cervical wear after simulated 3-year random toothbrushing. Cervical macro- and microwear of cementum revealed, for the first time, what we describe as overhanging enamel peninsulas and enamel islands on roots in young teeth, but no enamel islands on roots from older teeth after root cementum loss. In contrast, many older teeth exhibited enamel peninsulas.

Periodontal pockets: Predictors for site-related worsening after non-surgical therapy-A long-term retrospective cohort study

AIM

To evaluate site-related changes in periodontal pocket depth (PPD) after non-surgical periodontal therapy and to identify predictors for PPD changes in a retrospective patient data analysis.

MATERIALS AND METHODS

PPD, clinical attachment level, bleeding on probing, tooth mobility (TM), furcation involvement (FI), abutment status, adherence to supportive periodontal care (SPC) and SPC follow-ups were obtained from fully documented patient data before periodontal therapy (baseline, T0), after active periodontal therapy (APT, T1) and during SPC (T2). PPD changes were classified into deteriorated or unchanged/improved at the site level. Multi-level logistic regression analysis was performed to identify factors influencing PPD changes during SPC.

RESULTS

This retrospective study included 51 females and 65 males (mean T0 age: 54.8 ± 10.1 years, 25 smokers, 12 diabetics) suffering from Stage III/IV periodontitis. Evaluation outcome: T0/16,044 sampling sites/2674 teeth; T1/15,636/2606; T2/14,754/2459. During 9.0 ± 2.3 years SPC, PPD decreased (-1.33 ± 0.70 mm) by 21.8% of the sites, remained unchanged by 41.4% and increased (1.40 ± 0.78 mm) by 36.8%. Distopalatal FI (p < .001, odds ratio [OR]: 0.252, 95% confidence interval [CI] for OR: 0.118-0.540), residual pockets (p < .001, OR: 0.503, 95% CI: 0.429-0.590) and TM Degrees I-III (Degree I: p = .002, OR: 0.765, 95% CI: 0.646-0.905; Degree II: p = .006, OR: 0.658, 95% CI: 0.489-0.886; Degree III: p = .023, OR: 0.398, 95% CI: 0.180-0.879) correlated significantly with increasing PPD.

CONCLUSIONS

Over 75% of PPD remained unchanged or increased during SPC. Distopalatal FI, TM Degrees I-III and residual pockets after APT lead to worsening of periodontal pockets.

In-vitro comparison of two different toothbrush bristles about peri-implant sulcus penetration

OBJECTIVE

The aim of this preclinical study was to compare the ability of tapered and cylindrical bristles to penetrate the peri-implant sulcus.

METHODS

A full mandibular dental arch was reproduced in plaster cast. In site #3.6 a hollow glass cylinder was positioned simulating a 4 mm diameter implant and the gingival component was recreated by using dedicated silicone. A Bass brushing technique was performed from the vestibular side in humid environment. During it, the penetration of the bristles between the gum and the implant was recorded by mean of an optic fibre fixed inside the cylinder. The protocol included 5 toothbrushes per group and 10 tests per toothbrush, for a total of 50 assessments for each of the two groups. A scale of 5 grades for bristle penetration was defined: grade 0 (× < 2 mm), grade 1 (2 ≤ × < 3 mm), grade 2 (3 ≤ × < 4 mm), grade 3 (4 ≤ × < 5 mm) and grade 4 (5 ≤ × < 8 mm). From the video recordings the highest value of penetration was identified for each test.

RESULTS

The tapered bristles showed an 8 times greater penetration capacity (p = 0.001) in respect to the cylindrical bristles (multilevel analysis). The percentage of tests reaching depths ≥3 mm was 86% for tapered group and 28% for the cylindrical group.

CONCLUSION

This preclinical study shows a clear and superior penetration capacity of the tapered bristles in respect to traditional cylindrical ones. For tapered bristles, a potentially greater hygienic efficacy around dental implants is suggested.

Supra- and sub-gingival instrumentation of periodontitis with the adjunctive treatment of a chloramine - a one-year randomized clinical trial study

Periodontitis is a bacterial-induced disease and for this reason controlling the microbiota is a necessity. Therapy includes self-performed daily oral hygiene in combination with supra- and sub-gingival instrumentation. An adjunctive antimicrobial agent may improve the outcome.

AIMS

To assess whether a chloramine (Perisolv®) has an adjunctive effect to non-surgical periodontal therapy and whether non-surgical periodontal therapy affects quality of life.

MATERIAL AND METHODS

Thirty-eight patients were randomized to a test or a control group. Clinical indices were performed at baseline and at three and twelve months. In the test group, Perisolv® was applied initially and after the sub-gingival instrumentation in pathological pockets. Oral health-related quality of life was measured with the Oral Health Impact Profile (OHIP) instrument at baseline and twelve months.

RESULTS

In both groups, an initial probing pocket depth (PPD) of > 4 mm and bleeding on probing (BOP) were statistically reduced (p < 0.002 and p < 0.002 respectively) at twelve months and after adjustment for Bonferroni. There were no significant differences between the test and the control group in terms of the number of PPD, BOP or plaque index, or in the mean OHIP score.

CONCLUSIONS

Chloramine did not have an adjunctive effect, but the overall therapy was significantly efficacious both clinically and in terms of quality of life.

TRIAL REGISTRATION

Registered at www.

CLINICALTRIALS

gov:NCT05757921.

Longevity of extrinsic stains on monolithic zirconia restorations: An in vitro study

STATEMENT OF PROBLEM

Three-mol% yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP) has been commonly used for fixed prosthodontic restorations. The opacity of 3Y-TZP may be masked with external staining, although the longevity of extrinsic stains applied to monolithic zirconia is unclear.

PURPOSE

The purpose of this in vitro study was to analyze the color and surface roughness of extrinsically stained zirconia specimens after thermocycling and toothbrushing.

MATERIAL AND METHODS

Monolithic Ø12.5×1.25-mm zirconia disks were milled from 3Y-TZP blocks, sintered according to manufacturer instructions, and then divided into 3 groups (C, J, and O; n=16) for application of stain and glaze. All specimens underwent 10 000 thermocycles in distilled water before being further divided into 2 dentifrice groups (n=8): normal grit, low relative dentin abrasivity (RDA) (Subgroup N) and abrasive grit, high RDA (Subgroup A). Specimens were brushed in a multistation brushing machine under 1.47 N of force using a 5:8 toothpaste and distilled water slurry for 10 000 cycles with a straight (American Dental Association Standard) toothbrush to simulate 1 year of toothbrushing. Color and surface roughness measurements were obtained at 3 time points: baseline, after thermocycling, and after brushing. A 2-way repeated measures ANOVA was used to independently assess changes in color and surface roughness with respect to thermocycling and brushing (α=.05).

RESULTS

Group J displayed no significant change in color for either dentifrice system (P>.05). However, a significant change in surface roughness was observed for both dentifrice subgroups (P<.001). Group C specimens displayed significant changes in color (P<.001) and surface roughness (P<.001) for both dentifrice systems. Group O specimens displayed significant changes in color (P<.025) for both dentifrice systems and significant changes in surface roughness (P<.004) for subgroup A, but no significant changes for subgroup N (P=.075).

CONCLUSIONS

Artificial aging of monolithic zirconia resulted in changes in color and surface roughness that did not surpass the thresholds for perceptibility and acceptability. This study failed to establish durability limits for extrinsic stains applied to 3Y-TZP.

Impact of manual toothbrush design on plaque removal efficacy

BACKGROUND

Effective dental plaque removal is essential for oral health. Different toothbrush parameters including head-size, filament-diameter and interdent-height and different brushing movements like horizontal, rotating and vertical may affect plaque removal efficacy. The purpose of the study was to examine plaque removal efficacy of different design parameters of manual toothbrushes.

METHODS

Eight manual toothbrushes were tested using a validated robot test to examine efficacy of toothbrush on replicated human teeth. Characteristics tested were: (i) head-size, (ii) filament-diameter, (iii) cutting-height, (iv) hardness, (v) interdental-height. Each test ran five times in horizontal, rotating, vertical movements. Simulated Plaque removal was evaluated using automated plaque planimetry: 30 fields/tooth, 13 areas representing buccal, lingual, proximal tooth sites. The Kolmogorov-Smirnov-test was applied to test tooth surface variables for normal distribution of plaque removal values. Parameters were analysed by independent two-sample t-test to assess mean differences. Where null hypothesis of normality was rejected, the Wilcoxon-Mann-Whitney-U-test was used.

RESULTS

Plaque removal was significantly better with toothbrush having smaller head-size (compact vs. full-size); smaller filament-diameter (0.12 mm vs. 0.15 mm); larger cutting-height (12 mm vs. 9 mm); softer filaments (0.15 or 0.18 mm vs. 0.23 mm) and greater interdent-height difference (8.5/11 mm vs. 10/11 mm).

CONCLUSIONS

Manual brushes allowing filaments free to flex with longer, softer and/or having a difference in filament length overall removed significantly more simulated plaque as compared to more standard flat trim, stiff brushes with shorter, harder bristles and a larger head size. While limited by the in vitro nature of the study design, this indicates that the advances in toothbrush design can further enhance plaque removal.

Modeling contact forces during human-robot interactions for performing activities of daily living

This study aims to characterize contact forces between humans and tools during activities of daily living (ADL) to provide information to a personal care robot. The study was conducted on non-impaired subjects to capture various static and dynamic force levels when making contact with three different robotic tools, each designed to perform an ADL task: hair brushing, face wiping, and face shaving. The static trial of the study involved 21 participants. Forces were collected at fixed locations for each task and used to develop models for each participant. Extraction of the maximum force levels was performed for both the maximum and desired levels of force. The dynamic trial involved 24 individuals. Participants were asked to maintain a comfortable level of force for the duration of their contact with the tool as the robot moved along its path to perform the ADL task. For the static and dynamic trials, higher forces were observed during hair brushing compared to the other two tasks. It was observed that the hair brushing task force at a specific contact point has an overall maximum of 55.66 N, while the maximum forces detected in the face wiping and face shaving tasks were 36.40 and 11.11 N, respectively. The forces collected were analyzed, and no trends were found relating the contact forces to the gender, height, or weight of the subjects. Based on the analysis of the results, recommendations have been made to enhance the force safety limits for the personal care robot working environment.

Effect of Different Artificial Staining Procedures on the Color Stability and Translucency of a Nano-Hybrid Resin-Based Composite

BACKGROUND

To evaluate the effect of different experimental staining procedures on color stability and translucency of a nano-hybrid resin-based composite (RBC).

METHODS

Forty-eight cylindrical-shaped specimens (10 × 2 mm) were prepared with a nano-hybrid RBC (Clearfil Majesty ES-2) and randomly divided in four groups according to the experimental staining procedure: G1) static immersion in a staining solution (coffee) (44 ± 1 °C); G2) staining cycling between coffee (44 ± 1°C) and distilled water (37 ± 1°C) with an experimental staining machine based on Arduino, an Open Source hardware development platform; G3) staining cycles as in G2 + brushing with a low abrasive toothpaste (Relative Dentin Abrasion RDA = 30) (Elmex Sensitive Professional); G4) staining cycles as in G3, with brushing performed with a very strong abrasive toothpaste (RDA = 90) (Lacult Active). Color parameters were recorded at the baseline (T0) after staining procedures (T1) and repolishing (T2) using a spectrophotometer. Color change (∆E00) and translucency (TP, CR) were evaluated. Data were statistically analyzed (p < 0.05).

RESULTS

For ∆E00 after staining, Group 1 showed the highest color change and Group 3 the lowest. All groups were significantly different (p < 0.001) except for Group 2 vs. Group 4; after repolishing, Group 1 was significantly higher than Group 3 (p < 0.001), Group 2 (p < 0.001), and Group 4 (p = 0.003); Group 2 was higher than Group 3 (p < 0.001). For TP variable, after staining procedures, Group 2 was significantly higher than all other groups (p < 0.001), and Group 1 was significantly higher than Group 3 (p < 0.001) and Group 4 (p = 0.007). After repolishing, Group 4 was significantly lower than Group 3 (p = 0.008) and Group 2 (p = 0.027). Repolishing procedure significantly reduced color parameters.

CONCLUSIONS

The investigated staining procedure induced significant differences in color stability and translucency. The use of a very strong abrasive toothpaste (RDA = 90) induced higher color change than a low abrasive one (RDA = 30). Repolishing procedures are able to partially reduce color change induced by artificial staining procedures.

Effect of brushing force on the abrasive dentin wear using slurries with different abrasivity values

OBJECTIVE

The aim of this study was to investigate the resulting abrasive dentin wear using abrasive slurries with different RDA values and applying increasing brushing forces.

METHODS

Forty-five bovine incisors were randomly allocated in three groups (A, B, C, n = 15). One hundred and eighty dentin samples were prepared from these incisors and allocated to twelve groups (A1-A4, B1-B4, C1-C4; n = 15). The groups were subjected to a brushing cycle (120 strokes/min, 25 min) as follows: groups A1 to A4 with an abrasive slurry (RDA = 71) applying increasing brushing forces (1, 2, 3 and 4 N). Groups B1 to B4 were brushed using an abrasive slurry (RDA = 85) and C1 to C4 (RDA = 133) applying the same above-mentioned brushing forces. Abrasive dentin wear was recorded using a stylus profilometer and compared amongst the groups using robust models. Pairwise comparisons in each model were tested and corrected after Tukey's method (α = 0.05).

RESULTS

Applying 1-N brushing force resulted in the same amount of abrasive dentin wear in all groups regardless of the abrasivity of the used slurry. Increasing the brushing force to 2 N resulted in statistically significantly higher abrasive wear in all groups. This increase in abrasive wear was much higher when the slurry with high abrasivity was used (RDA = 133) compared with the lower abrasive slurry (RDA = 71).

CONCLUSION

The abrasivity of the used slurry does not add to the resulting abrasive wear when the brushing force is kept at 1 N. It seems better to advise and help the patients (showing signs of non-carious cervical lesions) calibrating their brushing force to 1 N, than only to advise them to use toothpastes with lower abrasivities.

Association between Dental Caries and Handgrip Strength: In a Population-Based Study in Korea (KNHANES 2016-2018)

This study aimed to verify the relationship between handgrip strength and oral health using data from the Korea National Health and Nutrition Examination Survey, representing Korean adults. Data from the seventh survey (2016−2018) conducted by the Korea Centers for Disease Control and Prevention were utilized, and 10,607 final study participants were recruited according to the selection and exclusion criteria. A complex sample logistic regression analysis was performed to confirm the relationship between handgrip strength and dental caries according to the sex of the study participants. On analyzing the correlation in men, “C1 (DMFT: 11−32),” when compared to “C4 (DMFT: 0−3),” in Model 1 without adjustment for potential confounders, was 2.92 (95% confidence interval [CI]: 2.15−3.97) times more likely to be associated with lower handgrip strength, and a statistically significant result was detected (p < 0.001). Additionally, significant odds ratios (ORs) were confirmed for all adjusted models. In women, the ORs in Model 1 without adjustment for potential confounders were 1.41 times (95% CI: 1.14−1.75) and demonstrated a significant result; however, the results were not significant in all adjusted models 2−4. Resultantly, a significant association was detected between dental caries and handgrip strength in Korean adults.

Plaque removal by a novel prototype power toothbrush versus a manual toothbrush: A randomized, exploratory clinical study

OBJECTIVES

This exploratory study investigated plaque removal with a prototype constant, low rotation speed Power Toothbrush (PTB) with two brushing actions: "Gumline" (head rotates in the horizontal axis) and "Interdental" (head rotates in the vertical axis). Gumline alone and "Combined" (Gumline + Interdental) modes were compared with a Reference PTB and a Reference Manual Toothbrush (MTB) after one brushing.

MATERIALS AND METHODS

Thirty-nine participants were randomized to use each toothbrush once either in the sequence (A) Prototype PTB (in Gumline then Combined mode), (B) reference MTB, and (C) reference PTB or the sequence BAC. There was a minimum 3-day washout between the use of each toothbrush. Plaque removal was measured using the Rustogi Modified Navy Dental Plaque Index (RMNPI) with change from baseline investigated using an analysis of covariance model. RMNPI scores were calculated on a "whole mouth" basis and along the gingival margin and at proximal sites only.

RESULTS

For the primary efficacy variable, a significant difference was found in favor of the prototype PTB in gumline mode versus the reference MTB for whole mouth plaque score (difference: -0.06; standard error: 0.014; 95% confidence interval [CI] -0.09 to -0.04; p < .0001). Similar significant differences were found in gingival margin and proximal areas (p < .0001). The prototype PTB in gumline mode removed significantly less plaque than the prototype PTB in combined mode and the reference PTB (p < .0001; whole mouth/gingival/proximal areas). The prototype PTB in combined mode removed significantly more plaque than the reference MTB (p < .0001; whole mouth/gingival/proximal areas) and the reference PTB for whole mouth (p = .0214) and gingival margin areas (p = .0010). The reference PTB also removed significantly more plaque than the reference MTB (p < .0001; whole mouth/gingival/proximal areas). All brushes were generally well-tolerated.

CONCLUSION

The prototype PTB design, providing two distinct cleaning modalities, can effectively remove plaque to a significantly higher degree than an MTB and a marketed PTB, depending on mode.

Powered toothbrushes for plaque control in fixed orthodontic patients: a network meta-analysis

BACKGROUND

Orthodontic patients are at greater risk due to the inability to clean around the components directly bonded to teeth. Hence, the aim of the present network meta-analysis is to compare the utility of powered toothbrushes in plaque control in patients with orthodontic brackets compared with manual tooth brushing.

METHODOLOGY

Necessary data were extracted and analysed for Risk of Bias. Heterogeneity was assessed using Chi-square and I2 tests. Random effects model was used for both direct and mixed treatment comparisons. Standardized mean difference with 95% confidence interval was the effect estimate for plaque and bleeding scores and mean difference for pocket depth. Inconsistencies between the direct and indirect estimates were evaluated by H-statistics. GRADE approach was used to assess the quality of evidence.

RESULTS

Pooled results from 14 studies showed significantly higher plaque scores in patients using manual toothbrushes. Pooled results from 13 studies showed significant higher bleeding scores as well with manual brushes. There was a significant reduction in pocket depth with electric toothbrushes.

CONCLUSION

Powered toothbrushes are a promising alternative for plaque control in patients with fixed orthodontic brackets. Stronger evidence can be established with addition of long-term clinical trials based on the recommendations.

Toothbrushing Performance and Oral Cleanliness after Brushing in 12-Year-Old Children

Objectives:

Nationwide prevention programs in Germany aim to promote oral health. The group prevention program starts in kindergarten and ends when the children are about 12 y old. While in a recent study, toothbrushing behavior of 12-y-old children was analyzed, the present study’s objective was to examine the children’s ability to achieve oral cleanliness and to analyze how toothbrushing behavior and compliance with the toothbrushing recommendations taught in the group prevention programs predict oral cleanliness.

Methods:

Twelve-year-old randomly selected children (N = 174) were asked to brush their teeth to the best of their abilities, and simultaneously a video was recorded for behavioral analyses. Plaque levels were measured before and immediately after toothbrushing. In addition, dental status and gingival bleeding were assessed.

Results:

After brushing to the best of their abilities, there was plaque on 50% (±24.72%) of all measured sites at the gingival margin (Marginal Plaque Index). Regression analyses revealed approximately 22% of the variance of marginal plaque on the outer surfaces to be explained by the time brushed by circular movements (β = −0.41;P < 0.001) and the number of sextants brushed for at least 7.5 s (β = −0.171; P < 0.05). Circular movements explained most additional variance (ΔR² = 0.113; P < 0.001). With respect to inner surfaces, none of the behavioral aspects explained any variance of oral cleanliness.

Conclusion:

Despite regular group prevention measures, 12-y-old children show limited skills to clean their teeth adequately. Furthermore, none of the recommended behaviors relates to oral cleanliness after toothbrushing at inner surfaces. As a consequence, it is necessary to explore further which behavioral sequences effectively improve oral cleanliness.

Knowledge Transfer Statement:

This study illustrates that children’s compliance to toothbrushing recommendations is not necessarily related to toothbrushing effectiveness. Clinicians should therefore assess the effectivity of recommendations individually and provide individual guidance for improvement.

Safety and Design Aspects of Powered Toothbrush-A Narrative Review

The powered toothbrush has become a modern dental tool that is available in the supermarket. Indeed, the design of the powered toothbrush, e.g., mechanical and electrical, would affect not only the efficacy but also the safety of the products. This narrative review attempted to view the powered toothbrush from design, safety, and application points with respect to tufts, filaments, handles, mechanics, motions, and materials interactions from various available sources. Different brands and models of powered toothbrushes have their own designs that might affect the clinical outcome. The rotational design was advocated to be clinically more effective than the manual one, some modern models might be designed with vibrational or oscillation (or mixed) tufts head that might be useful in patients with specific needs, such as having xerostomia or for the elderly. To conclude, tuft retention design is important in the powered toothbrush as it contributes significantly to safety as the fallen off tufts, filaments and metal parts might cause injury. Tests revealing the retention force of brush head plates and brush head bristles will be significant references for consumers to determine which design of powered toothbrushes is relatively safer.

Knowledge and Attitude Toward Electric Toothbrush Use Among Dental Professionals in Saudi Arabia

Background:

Proper knowledge and awareness regarding electric toothbrushes may decrease the incidence of caries and indirectly reduce the burden of oral disease on the developing economy by preventing plaque-related disease on a population level.

Aims and objectives:

The aim of this study was to assess the knowledge and attitude toward electric toothbrush use among dentist in Saudi Arabia.

Materials and methods:

An analytical cross-sectional study was conducted among 417 dentists in Saudi Arabia. For this study, an interview-type questionnaire comprising 14 questions was designed. These questions were asked from different dentists randomly through a telephonic survey. The first part of the questionnaire was related to the basic demographic details of the dentists, that is, gender, age, type of practice, dental education, specialty, and experience, whereas the second part of the questionnaire was designed to extract the experience, attitude, and opinion of the dentists regarding electric toothbrushes. The data were compiled and analyzed using Statistical Product and Service Solutions, version 20 (SPSS Inc., Chicago, IL, USA). Descriptive statistics were employed to calculate means and percentages for demographic data.

Results:

Among the dental participants, 171 (41.0%) were general practitioners, 163 (39.0%) were specialist, 23 (5.6%) were postgraduate students, and 60 (14.4%) were graduate dentists. A total of 271 (65%) respondents believed better patient compliance to be the main benefit of the electric toothbrush, whereas 325 (77.9%) respondents believed that poor patient compliance was the reason for patient’s poor plaque control. Similarly, 319 (76.5%) dentists endorsed patients with manual dexterity issues. Those dentists primarily recommended electric toothbrushes to patients with medical problems.

Conclusions:

Knowledge of dentists in Saudi Arabia is adequate regarding electric toothbrushes; efforts should be made to improve knowledge and awareness on the use of powered toothbrushes at the patients’ level.

Efficacy of a rubber bristles interdental cleaner compared to an interdental brush on dental plaque, gingival bleeding and gingival abrasion: A randomized clinical trial

AIM

To determine the efficacy of a rubber bristles interdental cleaner (RBIC) compared to an interdental brush (IDB) in reducing gingivitis and additionally to evaluate participants' attitudes and possible side effects.

MATERIAL AND METHODS

The study was a 2-treatment, parallel, split-mouth, examiner-blind RCT, evaluating the reversal of experimental gingivitis. In total, 42 systemically healthy volunteers were recruited that were currently non-users of interdental cleaning devices. After familiarization and prophylaxis, participants refrained from brushing mandibular teeth for 21 days, followed by 4-week product use of the assigned interdental cleaning device as adjunct to manual toothbrushing. Bleeding on marginal probing (BOMP), dental plaque index score (PI) and gingival abrasion score (GAs) were assessed in the lower jaw.

RESULTS

Overall, no statistically significant differences between the RBIC and IDB in reducing BOMP and PI were obtained. Analysing the sites that were accessible for the RBIC/IDB only showed that the sites treated with the RBIC had significantly less BOMP after 4 weeks (P = .009). The RBIC also caused less GAs (P => .016) and was considered more pleasurable to use by the participants (P = .0001).

CONCLUSIONS

In accessible sites, the RBIC, in conjunction with manual toothbrushing, was found to be more effective in reducing gingival inflammation after 4 weeks. The RBIC caused less abrasion of the gingiva and was appreciated more by the participants.

Influence of Bristle Stiffness of Manual Toothbrushes on Eroded and Sound Human Dentin--An In Vitro Study

Aim

The aim of this study was to determine the influence of manual toothbrushes with different bristle stiffness on the abrasivity on eroded and sound human dentin.

Materials and Methods

Dentin specimens were made from impacted third molars and attributed to three groups: erosion-abrasion (EA), abrasion (A) and erosion (E). The specimens from EA and E were treated with 1% citric acid (pH 2.3) for 1 min rinsed, and neutralized with artificial saliva for 15 min. This cycle was repeated five times. Thereafter, specimens from EA and A were treated with three toothbrushes types with different bristle stiffness (soft, medium, and hard) in a custom-made toothbrushing machine. The brushing was performed at a load of 3 N with a toothpaste slurry for 630 s. This procedure was repeated five times, in group EA after each erosion cycle. EA and A groups passed through five cycles with a total of 6300 strokes. The abrasivity was analyzed by contact-free profilometry. Kruskal-Wallis and Mann-Whitney U tests were performed for statistical analysis.

Results

With respect to bristle stiffness there was no statistically significant difference in dentin loss within the EA group. In group A, a statistically significantly higher dentin loss was found for the soft in comparison to the hard bristles. No statistically significant differences were measured between soft/medium and medium/hard toothbrushes. The amount of dentin loss from specimens in the EA group was significantly higher than in the A group.

Conclusions

Within the limitations of this study, the dentin loss in the Abrasion group was higher with soft bristles than with hard ones. This result might have an influence on the toothbrush recommendations for patients with non-carious cervical lesions.

Effect of toothbrushing on shade and surface roughness of extrinsically stained pressable ceramics

STATEMENT OF PROBLEM

The effect of toothbrushing on extrinsically stained pressable ceramic materials is unknown.

PURPOSE

The purpose of this in vitro study was to investigate the effects of toothbrushing on the shade and surface roughness of extrinsically stained, pressable ceramics.

MATERIAL AND METHODS

Two materials, leucite-based (IPS Empress Esthetic [EE]; Ivoclar Vivadent AG) and lithium disilicate-based ceramic (IPS e.max Press [EP]; Ivoclar Vivadent AG), were studied. For each material, 24 disk-shaped specimens, 10 mm (diameter)×3 mm (height) were fabricated. Three different methods (n=8) of applying extrinsic stains were performed on each material: glazed only (G, control group); stained then glazed (SG); and stained and glazed together (T). The specimens were brushed with a multistation brushing machine under a load of 1.96 N at a rate of 90 strokes per minute with a soft and straight toothbrush (Oral-B #35) and a 1:1 toothpaste and distilled water slurry. Shade and roughness were measured at baseline and at 72, 144, 216, and 288 hours, which is equivalent to 3, 6, 9, and 12 years of simulated toothbrushing for 2 minutes twice a day. A repeated measures ANOVA with staining technique as a fixed factor was used to evaluate shade and roughness (α=.05).

RESULTS

For EE groups, no significant change was found after 12 years of simulated toothbrushing regarding shade and surface roughness, irrespective of staining techniques (P>.05). However, EP groups demonstrated a significant shade change and an increase in surface roughness after 12 years of simulated toothbrushing. Shade change was found to depend on the method of applying stain. For the EP-SG technique, a significant shade change was observed only at the 9- to 12-year interval (P=.047). However, the EP-T technique demonstrated a significant difference in shade between baseline and 3 years (P=.005) and in the 6- to 9-year interval (P=.005). Surface roughness was only significantly affected at baseline and 3 years for the EP-T group (P=.005).

CONCLUSIONS

For the shade and surface roughness of the EE groups, no statistically significant difference was found after 12 years of toothbrushing, irrespective of the staining technique. The shade and surface roughness of the EP groups were significantly statistically affected by toothbrushing time; only shade changes were found to depend on technique.

The effect of oral care on intracranial pressure in critically ill adults

A major goal in the care of patients with neurological problems is to prevent or minimize episodes of increased intracranial pressure (ICP). Elevations in ICP in response to nursing interventions have been acknowledged since the 1960s when ICP monitoring was first introduced in the clinical setting. Until recently, few studies have specifically examined the effect of oral care on ICP, and oral care and other hygiene measures were combined or not specified, prohibiting a direct interpretation of the influence of oral care alone on ICP. The purpose of this study was to describe the relationship between routine oral care interventions and the changes in ICP specifically focusing on the effect of intensity and duration of this intervention. Twenty-three patients with a clinical condition requiring ICP monitoring were enrolled over a 12-month period. Oral care provided by neuroscience intensive care nurses was observed and videotaped. Characteristics of the intervention were documented including products used, patient positioning, and duration of the intervention. A 1-5 subjective scale was used to score intensity of oral care. Wrist actigraphy data were collected from the nurses to provide an objective measure of intensity. Patient physiologic data were collected at 12-second epochs 5 minutes before, during, and 5 minutes after oral care. The mixed-effect repeated measures analysis of variance model indicated that there was a statistically significant increase in ICP in response to oral care (p = .0031). There was, however, no clinically significant effect on ICP. This study provides evidence that oral care is safe to perform in patients in the absence of preexisting elevated ICP.

Tooth brushing inhibits oral bacteria in dogs

In this study, scaling, polishing and daily tooth brushing were performed in 20 beagle dogs, and the number of oral bacteria was determined using a bacterial counter. The dogs were randomized into the scaling (S), scaling + polishing (SP), scaling + tooth daily brushing (SB) and scaling + polishing + tooth daily brushing (SPB) groups. Samples were collected from the buccal surface of the maxillary fourth premolars of the dogs immediately after scaling and every week thereafter from weeks 1 to 8. Throughout the study, the number of bacteria was significantly lower in the SB and SPB groups compared with the S group. The findings suggest that daily tooth brushing inhibited oral bacterial growth in the dogs.

Efficacy of homecare regimens for mechanical plaque removal in managing gingivitis a meta review

FOCUSED QUESTION

Based on evidence as presented in systematic reviews what is the efficacy and safety of available homecare toothbrush regimens for mechanical plaque removal on plaque and gingivitis in adults?

MATERIAL & METHODS

Three Internet sources were used (up to and including August 2014) to search for appropriate papers that satisfied the study purpose. Plaque scores and gingivitis scores were considered to be the primary parameter of interest. Safety was considered an important facet in relation to efficacy. Data and conclusions as presented in the selected papers were extracted. The potential risk of bias was estimated and the emerging evidence was graded.

RESULTS

Independent screening of 176 unique reviews resulted in 10 published and eligible systematic reviews. They were categorized into one review evaluating the effect of an oral hygiene instruction with a toothbrush on plaque and gingivitis scores, five evaluating the efficacy of manual and power toothbrushes and three reviews evaluating toothbrush safety and one evaluating toothbrush contamination.

CONCLUSION

Tooth brushing is effective in reducing levels of dental plaque. With respect to gingivitis power toothbrushes have a benefit over manual toothbrushes. The greatest body of evidence was available for oscillating-rotating brushes. Tooth brushing generally can be considered safe for the teeth and their investing tissues.

Resistance of dentin coating materials against abrasion by toothbrush

Thin-film coating of root dentin surface by all-in-one adhesives has been shown to be an effective option to prevent root surface caries. The purpose of this study was to investigate the wear resistance against toothbrush abrasion of two all-in-one coating materials; Shield Force (SF) and Hybrid Coat (HC). Bovine dentin surfaces were covered with one of the coating materials; SF or HC. After storage in water for 24 h, the testing surface was subjected to the toothbrush abrasion test up to 50,000 cycles either in water or toothpaste slurry. The remaining thickness of the coating material was measured using SEM. Toothpaste slurry significantly increased rate of tooth brush abrasion of the coating materials. While SF and HC wore at a similar pace under toothbrush abrasion, SF had a thicker coat and could protect dentin longer, up to 50,000 cycles.

Analysis of tooth brushing cycles

OBJECTIVE

The aim of this study was to demonstrate the effectiveness of an analysis of tooth brushing cycles using a system that measures tooth brushing motion and brushing force with an accelerometer and strain tension gage attached to a toothbrush.

BACKGROUND

Mechanical plaque removal with a manual toothbrush remains the primary method of maintaining good oral hygiene for the majority of the population. Because toothbrush motion has not been fully understood, it should be clarified by analysis of tooth brushing cycles.

METHODS

Twenty healthy female dental hygienists participated in this study. Their tooth brushing motions were measured and analyzed using an American Dental Association-approved manual toothbrush to which a three-dimensional (3-D) accelerometer and strain tension gage were attached. 3-D motion and brushing force on the labial surface of the mandibular right central incisor and the lingual surface of the mandibular left first molar were measured, analyzed, and compared. Multilevel linear model analysis was applied to estimate variables and compare motion and forces related to the two tooth surfaces.

RESULTS

The analysis of tooth brushing cycles was feasible, and significant differences were detected for durations and 3-D ranges of toothbrush motion as well as brushing force between the two tooth surfaces.

CONCLUSION

The analysis used in this study demonstrated an ability to detect characteristics of tooth brushing motion, showing tooth brushing motion to change depending on the brushed location. These results also suggest that more detailed instructions might be required according to patient's oral condition.

Effects of toothbrush hardness on in vitro wear and roughness of composite resins

AIM

To investigate and compare the effects of toothbrushes with different hardness on abrasion and surface roughness of composite resins.

MATERIALS AND METHODS

Toothbrushes (DENT. EX Slimhead II 33, Lion Dental Products Co. Ltd., Tokyo, Japan) marked as soft, medium and hard, were used to brush 10 beam-shaped specimens of each of three composites resins (Venus [VEN], Venus Diamond [VED] and Venus Pearl [VEP]; HeraeusKulzer) with standardized calcium carbonate slurry in a multistation testing machine (2N load, 60 Hz). After each of five cycles with 10k brushing strokes the wear depth and surface roughness of the specimens were determined. After completion of 50k strokes representative samples were inspected by SEM. Data were treated with ANOVA and regression analyses (p < 0.05).

RESULTS

Abrasion of the composite resins increased linearly with increasing number of brushing cycles (r² > 0.9). Highest wear was recorded for VEN, lowest for VED. Hard brushes produced significantly higher wear on VEN and VEP, whereas no difference in wear by toothbrush type was detected for VED. Significantly highest surface roughness was found on VED specimens (Ra > 1.5 µm), the lowest one on VEN (Ra < 0.3 µm). VEN specimens showed increased numbers of pinhole defects when brushed with hard toothbrushes, surfaces of VEP were uniformly abraded without level differences between the prepolymerized fillers and the glass filler-loaded matrix, VED showed large glass fillers protruding over the main filler-loaded matrix portion under each condition.

CONCLUSION

Abrasion and surface roughness of composite resins produced by toothbrushing with dentifrice depend mainly on the type of restorative resin. Hardness grades of toothbrushes have minor effects only on abrasion and surface roughness of composite resins. No relationship was found between abrasion and surface roughness.

CLINICAL SIGNIFICANCE

The grade of the toothbrush used has minor effect on wear, texture and roughness of the composite resin.

Evaluation of the tooth brushing skills in children aged 6-12 years

AIM

To evaluate the tooth brushing skills in children aged between 6 and 12 years and its relation with age, type of grip used, duration of brushing and gender.

METHOD

A total of 105 children aged between 6 and 12 years were divided into seven groups and their plaque scores, type of grip used and duration of brushing were assessed.

RESULTS

The most preferred grip was the distal oblique (58.1 %). Oblique, distal oblique and power grips were more efficient (plaque reduction up to 70 %). Plaque removal efficacy improved with age (57 % in 6-year-olds and 82 % in 12-year-old children). Plaque reduction was greater when the duration of brushing was longer (82 % plaque reduction when the brushing time was >2.5 min). Overall, the mean duration of tooth brushing in children aged 6-12 years was 1.71 min (103 s).

CONCLUSIONS

Tooth brushing skills improved with age and the duration of tooth brushing made a significant difference to the oral hygiene status of the child. The type of grip used and gender did not influence tooth brushing ability in this group of children. Tooth brushing skills were low in children younger than 10 years of age. Hence, parental supervision is considered necessary and recommended until 10 years of age.

A comparison of the efficacy of powered and manual toothbrushes in controlling plaque and gingivitis: a clinical study

BACKGROUND

Plaque is intimately related to the production and progress of dental caries and inflammatory gingival and periodontal diseases. Good plaque control facilitates the return to health for patients with gingival and periodontal diseases. Daily use of a toothbrush and other oral hygiene aids is the most dependable way to achieve oral health benefits for all patients.

METHODS

A randomized clinical trial was conducted to compare the efficacy of a powered toothbrush with a manual toothbrush in controlling plaque and gingivitis over a 6-week period. The sample consisted of 60 dental students of both sexes, with ages ranging from 18 to 28 years. The samples were stratified and randomly divided into two groups of 30 by a second examiner using the coin toss method; one group used a manual toothbrush and the other group used a powered toothbrush. Each participant's gingival index, plaque index and oral hygiene index were assessed on the seventh, 14th, and 45th days on the basis of the assigned toothbrush. Collected data were analyzed and different subgroups were compared using Student's t-test.

RESULTS

A paired t-test revealed a highly significant reduction in the gingival, plaque, and oral hygiene index scores of the manual and powered groups at the first, second, and sixth weeks (P-value < 0.0001). An unpaired t-test revealed a significant reduction between the plaque index scores of the manual and powered groups at the second week (P-value < 0.05). Another unpaired t-test revealed a highly significant reduction between the plaque index scores of the manual and powered groups at the sixth week (P-value < 0.0001).

CONCLUSION

The subject group using the powered toothbrush demonstrated clinical and statistical improvement in overall plaque scores. Powered toothbrushes offer an individual the ability to brush the teeth in a way that is optimal in terms of removing plaque and improving gingival health, conferring good brushing technique on all who use them, irrespective of manual dexterity or training.

Functionalization of titanium with chitosan via silanation: evaluation of biological and mechanical performances

Complications in dentistry and orthopaedic surgery are mainly induced by peri-implant bacterial infections and current implant devices do not prevent such infections. The coating of antibacterial molecules such as chitosan on its surface would give the implant bioactive properties. The major challenge of this type of coating is the attachment of chitosan to a metal substrate. In this study, we propose to investigate the functionalization of titanium with chitosan via a silanation. Firstly, the surface chemistry and mechanical properties of such coating were evaluated. We also verified if the coated chitosan retained its biocompatibility with the peri-implant cells, as well as its antibacterial properties. FTIR and Tof-SIMS analyses confirmed the presence of chitosan on the titanium surface. This coating showed great scratch resistance and was strongly adhesive to the substrate. These mechanical properties were consistent with an implantology application. The Chitosan-coated surfaces showed strong inhibition of Actinomyces naeslundii growth; they nonetheless showed a non significant inhibition against Porphyromonas gingivalis after 32 hours in liquid media. The chitosan-coating also demonstrated good biocompatibility to NIH3T3 fibroblasts. Thus this method of covalent coating provides a biocompatible material with improved bioactive properties. These results proved that covalent coating of chitosan has significant potential in biomedical device implantation.

Relationship between plaque score and video-monitored brushing performance after repeated instruction--a controlled, randomised clinical trial

OBJECTIVES

Aim of this prospective, randomised, controlled clinical trial was to use the modified bass technique (MBT) and a specific brushing sequence to investigate whether two types of instruction methods lead to differences in plaque reduction and whether plaque reduction is related to technique adoption.

METHODS

Ninety-eight participants were randomly assigned to three groups: (1) control, no instruction; (2) verbal instruction by means of a leaflet; and (3) verbal instruction supported by demonstration, no leaflet. Brushing performance was video monitored. Plaque score (Turesky modified QHI (T-QHI)) was measured at baseline, afterwards participants received instructions. After 2 weeks, T-QHI was measured for a second time, and participants were re-instructed. After another 2 weeks, T-QHI was measured for a third time.

RESULTS

At baseline, T-QHI did not differ between groups ((1) 1.99 ± 0.51, (2) 1.90 ± 0.51, (3) 1.93 ± 0.56). The second measurement revealed an improvement of T-QHI in the instructed groups and in the non-instructed control group ((1) 1.80 ± 0.47, (2) 1.58 ± 0.58, (3) 1.64 ± 0.58; n.s. between groups); in the intervention groups, remotivation achieved no further improvement ((1) 1.72 ± 0.48, (2) 1.52 ± 0.58, (3) 1.50 ± 0.69; n.s. between groups and compared to second measurement). Improvement of T-QHI was not related to proper performance of technique or brushing sequence. Those who fully adopted the brushing technique, the sequence or both did not have lower plaque scores.

CONCLUSION

Technical performance and effectiveness were not linked.

CLINICAL RELEVANCE

Within the study setting, the MBT was not effective in reducing plaque scores. The general recommendation of the MBT should be re-evaluated in further studies.

Effectiveness of a vegetable dental chew on periodontal disease parameters in toy breed dogs

Sixteen toy breed dogs completed a parallel, 70-day two-period, cross-over design clinical study to determine the effect of a vegetable dental chew on gingivitis, halitosis, plaque, and calculus accumulations. The dogs were randomly assigned into two groups. During one study period the dogs were fed a non-dental dry diet only and during the second study period were fed the same dry diet supplemented by the daily addition of a vegetable dental chew. Daily administration of the dental chew was shown to reduce halitosis, as well as, significantly reduce gingivitis, plaque and calculus accumulation and therefore may play a significant role in the improvement of canine oral health over the long-term.

Comparison of intraoral distribution of two commercially available chlorhexidine mouthrinses with and without alcohol at three different rinsing periods

Objectives:

This study compared the intraoral distribution of 0.1% chlorhexidine with alcohol (CHX+Alc) and 0.2% chlorhexidine without alcohol (CHX-Alc) with shorter rinsing times (10s,20s,30s) following a 72h non brushing period.

Materials and Methods:

This study was designed as a single blind, randomized two group parallel experiment with a total of 30(15male,15 female) dental students. To disclose the plaque, erythrosine-containing disclosing agent was added to both the mouthrinses. Group I (0.1% CHX+Alc) & Group II (0.2% CHX-Alc) were asked to rinse with respective mouthrinse for cumulative periods of 10,20 and 30s, following which plaque was scored.

Results:

In Group I, comparison between 10&20, 10&30s was statistically significant but no significance was observed between 20&30s, whereas in Group II, comparison between all the time points were statistically significant. On comparison of plaque scores, plaque scores of both the groups at 10 & 30s sec, show no statistical significance but at 20 seconds was significant (P<0.001). The mean plaque scores of lingual surfaces were lesser in group II whereas in group I lingual surfaces recorded more plaque than the vestibular surfaces.

Conclusions:

Within the limitations of this study, it can be concluded that rinsing for 30 seconds with 0.2% CHX-Alc (Rexidin) is enough for intraoral spread of the mouthrinse whereas rinsing with 0.1% CHX+Alc(Eludril) for achieves the same in 20 seconds, for effective plaque inhibition, both of which will have a positive influence on patient compliance.

Toothbrush Abrasion of Resin Composites with Different Filler Concepts

Purpose

To investigate the effect of tooth brushing wear with and without calcium carbonate slurry on four commercial resin composites based on different filler concepts.

Materials and methods

One nanofiller composite MI FIL (MFI, GC), one conventional hybrid type Venus (VEN) and two nanohybrid composites Venus Diamond (VED) and Venus Pearl (VEP) all from Heraeus Kulzer were examined. Forty beam-shaped specimens (12 × 3 × 3 mm) from each product were prepared and subdivided in two equal groups for pregrinding on SiC paper #600 and #4000 respectively. Ten specimens of each pre-ground group were subjected to toothbrush abrasion with calcium carbonate slurry, and 10 to toothbrushing with water only. The samples were submitted to five subsequent runs of 10,000 brushing strokes. Depth of wear and surface roughness (Ra) were measured with a profilometer after each 10 k strokes. Specimens after 50 k strokes were assessed by SEM. Additionally, the KHN (0.25 N/15 s) and the degree of conversion (DC) were determined. Data analysis was done by linear regression and ANOVA followed by Tukey's post-hoc test (p ≤ 0.05).

Results

Toothbrushing with abrasive slurry produced significantly different wear depths: VEN > MIF > VEP > VED. Linear relationships between depth of wear and number of cycles (r2 ≥ 0.94) were established for each material. Pregrinding with SiC #4000 resulted in less wear than pregrinding with #600. Ra figures were much higher for VED than for the other materials tested. MIF and VEN were uniformly abraded, whereas the largest glass fillers in VED protruded from the surroundings and the prepolymer particles in VEP were deeper abraded than the bulk of the material. Toothbrushing with water only revealed not measurable wear. Roughness Ra was practically unchanged when compared with the preground samples before challenging with toothbrushes. Ranking by KHN was: MIF < VEN, VEP < VED, by DC: MIF < VEN < VEP < VED.

Conclusion

Filler concepts and monomer compositions affect wear and roughness of resin composites when tooth brushed with abrasive slurry. Toothbrushing without abrasive medium produced neither wear nor roughness. Careful polishing of resin composite restorations is an important determinant of wear and surface roughness.

How to cite this article

Suzuki T, Kyoizumi H, Araki Y, Finger WJ, Kanehira M. Toothbrush Abrasion of Resin Composites with Different Filler Concepts. World J Dent 2012;3(2):184-193.

Non-surgical management of periodontal disease

Non-surgical removal of plaque and calculus has been part of the initial phase of the management of patients with gingivitis and periodontitis for decades. It consists of patient motivation and oral hygiene instruction as well as mechanical removal of supra and subgingival plaque deposits. The purpose of this review was to assess recent changes. The article reports on changes in our understanding of plaque as a biofilm, developments in patient plaque control, chemical plaque control and scaling instruments. It also comments on full-mouth disinfection, the use of lasers and host modulation. Modern technology has made removal of microbial deposits by the patient and dental professionals more efficient. However, other advancements need to be used in conjunction with mechanical debridement at this time.

Effects of an oral health promotion program in people with mental illness

More knowledge is needed regarding what works to prevent oral health problems and reduce disparities in oral health. Motivational interviewing (MI) has demonstrated utility for improving health behavior, including among those with severe mental illness. This study tests whether MI enhances the efficacy of an oral health education intervention in individuals with severe mental illness. Sixty individuals were randomly assigned to MI plus oral health education or oral health education alone. Plaque scores, oral health knowledge, and self-regulation were assessed at baseline and at 4 and 8 weeks. Repeated-measures ANOVA showed improvement (p < 0.05) in plaque, autonomous regulation, and oral health knowledge across time for both groups; however, individuals receiving MI improved significantly more when compared with those receiving oral health education alone. Results suggest that MI is effective for enhancing short-term oral health behavior change for people with severe mental illness and may be useful for the general population.

Tooth brushing habits in uninstructed adults--frequency, technique, duration and force

Professional recommendations for individual oral hygiene mostly include tooth brushing at least twice daily for 2-3 min with gentle force using the Bass technique or modifications of it. This study evaluated whether habitual tooth brushing actually meets these standards. Uninstructed adults (n = 103; mean age 31 +/- 6 years; 61 female, 42 male) with habitual manual tooth brushing were given a self-administered questionnaire about the frequency of brushing and a computer system recorded their brushing technique, duration and force. The majority (79.6%) of participants brushed twice daily. The mean brushing duration was 96.6 +/- 36.0 s, the mean brushing force was 2.3 +/- 0.7 N (max. 4.1 N), and no significant differences were found for quadrants. Most subjects (73.8%) brushed with circling, 8.7% with horizontal/scrubbing, 13.6% with horizontal/circling and 3.9% with vertical/sweeping movements. Modified Bass technique was not observed. When appropriate brushing habits were defined as brushing at least twice daily for 120 s with a brushing force of less than 3 N and with circling or vertical sweeping movements, only 25.2% of the participants fulfilled all criteria, emphasising the ongoing need for oral hygiene education.

The measurement of enamel wear by four toothpastes

OBJECTIVES

To determine the enamel abrasivity of three whitening toothpastes and a silica toothpaste and to measure the brushing forces used.

METHODS

Polished human enamel blocks were indented with a Knoop diamond and attached to dentures of adult volunteers. The blocks were brushed ex vivo, twice per day with either a whitening toothpaste containing Perlite (White System), a commercial whitening toothpaste (A and B) or a silica toothpaste. After four and twelve-weeks, one block per subject was removed and the Knoop indent remeasured. From the changes in the indent length, the amount of enamel wear was calculated.

RESULTS

The mean enamel wear (sd) for White System, silica toothpaste, whitening toothpaste A and B after four-weeks was 0.14 (0.15), 0.09 (0.16), 0.14 (0.12) and 0.89 (0.93) and after twelve-weeks was 0.24 (0.21), 0.37 (0.73), 0.36 (0.52) and 1.04 (0.98) microm respectively. After four-weeks, the differences in enamel wear between whitening toothpaste B and all other toothpastes were of statistical significance (p < 0.003), but not after twelve-weeks. The mean ex vivo normal brushing force (sd) was 2.67 (1.33) N.

CONCLUSIONS

All three whitening toothpastes did not give significantly more enamel wear than a silica toothpaste after twelve-weeks in situ with ex vivo brushing.

The Additional Effect of a Dentifrice on the Instant Efficacy of Toothbrushing: A Crossover Study

BACKGROUND

Inconclusive evidence exists in the literature with regard to the additional (beneficial) mechanical effect of a dentifrice on plaque removal. A previous split-mouth study found that a dentifrice did not contribute to plaque removal. Because of limitations of the split-mouth model, a crossover design was used to evaluate whether a commercially available dentifrice had an additional effect on mechanical plaque removal during manual toothbrushing.

METHODS

Thirty-six subjects were given a manual toothbrush and a standard dentifrice. After a 48-hour plaque accumulation, subjects brushed under supervision with or without a dentifrice (total time of 2 minutes) in a 2 x 2 crossover design.

RESULTS

Plaque reductions were 50% with and 56% without the use of dentifrice. This 6% difference was statistically significant (P = 0.034). Explorative analysis showed that brushing without a dentifrice was more effective in removing plaque on the approximal surfaces.

CONCLUSIONS

The use of a dentifrice did not contribute to mechanical plaque removal during manual toothbrushing. It seemed that the mechanical action provided by the toothbrush was the main factor in the plaque-removing process.

Inhibition of “De Novo” Plaque Formation With 0.12% Chlorhexidine Spray Compared to 0.2% Spray and 0.2% Chlorhexidine Mouthwash

BACKGROUND

Chlorhexidine (CHX) is widely accepted as the most effective product in the control of supragingival plaque. It is available in different delivery devices. The aim of this study was to test whether 0.12% CHX spray was as effective as 0.2% CHX spray and 0.2% CHX mouthwash in a 3-day "de novo" plaque formation model.

METHODS

Ninety volunteers were enrolled into a single-blind, randomized, three-group parallel study. They received a thorough dental prophylaxis prior to the test period. Subjects were divided randomly into three equal groups. They were requested to refrain from all forms of mechanical oral hygiene and instructed to use only their assigned product during the 3-day experimental period. After 3 days, the plaque growth was assessed using the Quigley and Hein plaque index (Q&H PI) at six sites per tooth.

RESULTS

After 3 days, the CHX mouthwash group had a mean Q&H PI of 1.17 compared to 1.41 for the 0.2% CHX spray and 1.49 for the 0.12% CHX spray. The difference between the mouthwash and the two sprays was statistically significant, whereas the two sprays did not differ significantly from each other.

CONCLUSIONS

Within the limitations of this 3-day "de novo" plaque formation study, the two sprays were not as effective as the mouthwash in plaque inhibition. No significant difference was found between the two sprays. To achieve the same effectiveness as a mouthwash, a higher dose (number of puffs) of CHX spray may be necessary.

Effectiveness of an oral hygiene chew to reduce dental deposits in small breed dogs

Over a period of 4-months, feeding small breed dogs with a regular dry diet supplemented with a daily oral hygiene chew resulted in a significant reduction in plaque deposition (17.3%) and calculus accumulation (45.8%) compared with dogs fed the dry diet alone. Daily feeding of a specifically designed oral hygiene chew that reduces plaque and calculus accumulation may play a role in the severity of canine periodontal disease.