Dentin erosive wear is reduced by fluoride varnishes containing nanosized sodium trimetaphosphate in vitro.

This study evaluated the effect of fluoride varnishes containing micrometric or nanosized sodium trimetaphosphate (TMP) on dentin erosive wear in vitro. Bovine root dentin blocks were selected by surface hardness and randomly divided into five experimental groups/varnishes (n = 20/group): placebo, 5% sodium fluoride (NaF); 5% NaF+5% micrometric TMP; 5% NaF+2.5% nanosized TMP; and 5% NaF+5% nanosized TMP. Half of the surface of all blocks received a single application of the assigned varnish, with subsequent immersion in artificial saliva for 6 h. Varnishes were then removed and the blocks were immersed in citric acid (90 s, 4×/day, 5 days). After each erosive cycle, ten blocks of each group were immersed in a placebo dentifrice for 15 s (ERO), while the other ten blocks were subjected to abrasion by brushing (ERO+ABR). Dentin erosive wear was assessed by profilometry. Data were submitted to 2-way ANOVA and to the Holm-Sidak test (p<0.05). Dentin erosive wear was significantly higher for ERO+ABR than for ERO for all varnishes. TMP-containing varnishes promoted superior effects against dentin erosive wear compared with 5% NaF alone; and 5% nanosized TMP led to the lowest wear among all varnishes. In conclusion, the addition of TMP to conventional fluoride varnish (i.e., varnish containing only NaF) enhanced its protective effects against bovine root dentin erosion and erosion+abrasion. Additionally, the use of 5% nanosized TMP led to superior effects in comparison to 5% micrometric TMP, both for erosion and erosion+abrasion in vitro.

Stain removal, abrasion and anticaries properties of a novel low abrasion dentifrice containing micro-fibrillated cellulose: in vitro assessments.

OBJECTIVES: This laboratory study assessed the performance of a novel fluoride dentifrice containing micro-fibrillated cellulose (MFC) and entrapped silica. METHODS: Removal of extrinsic stains was assessed using the pellicle cleaning ratio (PCR) method, and radioactive dentin abrasivity (RDA) was measured, to calculate a cleaning efficiency index (CEI). Fluoride efficacy was evaluated using widely used remineralization and fluoride uptake methods. The test product (Protegera™) was compared to common dentifrices (Crest - Cavity Protection™ and ProHealth™, Sensodyne Pronamel™, Arm & Hammer™ Advanced Whitening, Crest ProHealth™, and Colgate Optic White™). RESULTS: The PCR for the MFC dentifrice (141) was comparable to three known marketed stain-removing dentifrices (Arm & Hammer™ Advanced Whitening, Crest ProHealth™, and Colgate Optic White™) but it had a significantly lower RDA (88 ± 6) than 5 other products. This gave it the highest CEI of the tested products (2.0). In a 10-day pH cycling study, the fluoride efficacy of the MFC product was comparable to Sensodyne Pronamel and Crest Cavity Protection. The MFC dentifrice was superior for promoting fluoride uptake into incipient enamel lesions compared to the USP reference dentifrice. CONCLUSION: The MFC dentifrice has low abrasion, but despite this, it is highly effective in removing stained pellicle. It also is an efficacious fluoride source when compared to relevant commercially available fluoride dentifrices with high dentin abrasivity. CLINICAL SIGNIFICANCE: The addition of micro-fibrillated cellulose to a fluoride dentifrice gives a low abrasive product that can effectively remove external stains, and serve as an effective fluoride source. This combination of benefits seems well suited to enamel protection and caries prevention.

Toothpaste containing TiF4 and chitosan against erosive tooth wear in situ.

OBJECTIVE: This study compared the protective effect of an experimental TiF4/Chitosan toothpaste with a commercial toothpaste on the prevention of erosive tooth wear (ETW) in situ. METHODS: Fifteen subjects took part in this crossover and double-blind study, in which they wore a palatal appliance containing 4 bovine enamel and 4 dentin in 3 phases (5 days each). Half of the samples were subjected to erosive challenges (90 s in 0.1 % citric acid, pH 2.5, 4 times/day), and the other half to erosive plus abrasive challenges (15 s plus 45 s of contact, 2 times/day). The phases corresponded to the application of the different toothpastes: 1) TiF4 (1400 ppm F-) plus Chitosan, 2) Elmex®, Erosion Protection (1400 ppm F-, Chitosan), and 3) Placebo (negative control). Tooth wear was measured using contact profilometry (µm) and submitted to two-way RM ANOVA/Tukey test (p < 0.05). RESULTS: No significant differences were detected between the experimental and commercial toothpastes, regardless of the challenge on both tissues. Both significantly reduce ETW compared to negative control (p < 0.0006). Tooth wear was increased by brushing only on eroded enamel (p < 0.01), but not on dentin (p = 0.6085). TiF4/Chitosan [erosion 2.98 ± 1.12 µm vs. erosion and abrasion 3.12 ± 1.33 µm] and Elmex® toothpastes [erosion 2.35 ± 0.93 µm vs. erosion and abrasion 2.98 ± 1.0 µm] minimized the impact of brushing compared to placebo on enamel [erosion 4.62 ± 1.48 µm vs. erosion and abrasion 5.15 ± 1.50 µm]. CONCLUSIONS: TiF4 plus chitosan toothpastes showed to be effective in minimizing the ETW as the commercial toothpaste is in situ. CLINICAL RELEVANCE: The experimental toothpaste has similar effect against ETW compared to the commercial toothpaste. Considering the increased ETW prevalence worldwide, this result supports clinical trials and a possible application of this experimental anti-erosive toothpaste in the future.

Tooth surface loss: causes, management, and prevention.

OBJECTIVES: Tooth wear, also referred to as tooth surface loss, occurs due to causes other than caries. This involves the loss of hard tissues, namely enamel, dentin, and/or cementum. Types of tooth wear/tooth surface loss are abrasion, abfraction, attrition, and erosion. These multifactorial conditions can be caused by factors such as lifestyle, diet, or even habits, and may not be symptomatic. The focus of this article is to provide clinicians with detailed examples and explanations of the causes of tooth loss to aid in early diagnosis. Through early identification, the preventive measures outlined can be implemented to avoid excessive tooth wear. The provision of a treatment flowchart and general treatment recommendations aims to help clinicians determine when to restore these lesions and the most appropriate treatment measures for the four types of wear. METHOD AND MATERIALS: The PubMed (MEDLINE) search engine was used to gather information on teeth restricted to a 5-year period (26 August 2018 to 25 July 2022). Only English-language studies and reviews with the best balance of sensitivity and specificity were considered. A Boolean search of the PubMed dataset was implemented to combine a range of keywords: ("tooth wear" OR tooth attrition OR tooth erosion OR tooth abrasion OR tooth abfraction). Additional articles were selected through Google Scholar. RESULTS: By this process, many articles and studies were obtained, and the 48 most relevant published studies were chosen and used in the current review. CONCLUSION: Tooth wear affects an increasing number of individuals and can have detrimental effects physically, mentally, and emotionally. It is important to stress early diagnosis and management of tooth wear through monitoring, prevention, and treatment where indicated.

Characteristics of tin-containing fluoride toothpastes related to erosive tooth wear protection.

OBJECTIVES: To assess the effect of different tin-containing toothpastes on the control of erosive tooth wear in enamel and dentin. METHODS: Enamel and dentin slabs were randomly distributed into 7 experimental groups (n = 10/substrate): C-: negative control (Artificial saliva); AmF (regular fluoridated toothpaste without tin); Sn-1 (SnF2/NaF); Sn-2 (SnF2/NaF/SnCl2); Sn-3 (SnCl2/NaF); Sn-4 (SnF2/SnCl2); Sn-5 (SnCl2/AmF/NaF/chitosan). Specimens were submitted to 5-day erosion-abrasion cycling. Surface loss (SL) was determined with an optical profilometer. Tin deposition on the tooth surfaces and some characteristics of the toothpastes (pH, potentially available F-, %weight of solid particles, and RDA) were also assessed. Data were statistically analyzed (α = 0.05). RESULTS: For enamel, the Sn-2 presented the lowest SL, not differing significantly from AmF, C+, and Sn-3. The SL of these groups was significantly lower than the C-, except for Sn-3. Sn-1 and Sn-4 were also not significantly different from C-. For dentin, C- significantly showed the highest SL values, whilst, Sn-1 presented the lowest SL, not differing significantly from AmF, Sn-2, C+, and Sn-3. There was a significant positive association between enamel SL and the pH and tin deposition. Dentin SL was significantly negatively associated with the %weight of solid particles and RDA. CONCLUSIONS: Most of the tin-toothpastes were able to exhibit some protection against ETW. In this process, the toothpastes characteristics play a role, as lower enamel SL was significantly associated with lower pH values and tin deposition; and lower dentin SL was associated with higher %weight of solid particles and RDA of the toothpastes. CLINICAL SIGNIFICANCE: Tin-containing toothpastes can be used for erosive tooth wear protection, but our study showed that their effect depends on the pH, amount of tin deposition, % weight of solid particles and RDA of the toohpastes.

Description of a new laboratory evaluation method of interdental brush abrasion as a clinical hazard.

OBJECTIVES: To simulate the abrasive potential of an interdental brush when applied with toothpastes and prophylactic gels/solutions in a novel laboratory brushing simulation set-up. METHODS: A brushing device was customized to treat dentin samples mimicking a simplified interdental space with an interdental brush (ISO 2). The brushing, that is, 7200 strokes for 1 h, was performed with artificial saliva (control), a povidone-iodine solution, and slurries of chlorhexidine and fluoride gels as well as three toothpastes with different RDA values ranging from 29 to 100, respectively. The loss of dentin was profilometrically assessed and compared with ANOVA and Fishers LSD. RESULTS: While artificial saliva as control, the solution and the gel slurries showed no measurable dentin loss, toothpastes resulted in a measurable linear surface damage with respect to the actual intrinsic RDA values and ranged from 12.6 to 26.5 µm (p < 0.001). CONCLUSIONS: Any interdental cleaning product should be tailored and carefully instructed. Any over- and misuse should be avoided, which applies especially to the use of interdental brushes in combination with abrasive toothpastes.

The effect of location/site on polished human enamel after mechanical and chemical wear.

OBJECTIVE: To compare profilometry and microhardness of polished occlusal and buccal human enamel following a mechanical and chemical wear regime. METHODS: Enamel from polished human molars were sectioned into buccal and occlusal surfaces and randomly allocated into two groups (n = 10) and then exposed to 0.3 % citric acid at pH 2.7 for 10, 20, 40 and 60 mins each followed by abrasion with non-fluoridated toothpaste for 240 strokes in a reciprocating brushing machine. A white light profilometer with a spot size of 12 um measured mean step-height following each cycle. Microhardness indentations were conducted following the final cycled 60 mins erosion/abrasion using 0.01, 0.02, 0.1, 0.5 and 2.5 kgf indentation load. Statistical disparity were evaluated using a two-way ANOVA and post-hoc Sidak's multiple comparisons tests at α = 0.05. RESULTS: After erosion/abrasion, the mean (SD) step-heights on occlusal and buccal surfaces were not significantly different until 60 mins, when occlusal surfaces exhibited greater step-heights, 32.9 µm (2.8) and 31.1 µm (1.8) and p = 0.02, respectively. Buccal and occlusal microhardness was statistically lower following erosion/abrasion at loads of 0.01 kgf (p = 0.0005) and 0.02 kgf (p = 0.0006) but no significant differences were observed in the microhardness between the surfaces at any loads. CONCLUSION: The occlusal and buccal surfaces were not statistically different for microhardness or step height suggesting the susceptibility to wear is not related to the anatomy and structure of the tooth and is more likely related to other factors such as the environment. CLINICAL SIGNIFICANCE: The study emphasizes that a notable difference in wear between occlusal and buccal enamel surfaces emerges only after prolonged exposure to simultaneous chemical and mechanical stress. This finding necessitates a preventive dental approach that accounts for both the duration of exposure and environmental factors.

Supplementation of Energy Drinks with Green Tea Extract: Effect on In Vitro Abrasive/Erosive Dentin Wear.

PURPOSE: To investigate the effect of the supplementation of energy drinks with green tea extract on abrasive and erosive dentin wear. MATERIALS AND METHODS: Six groups, each comprising 15 bovine dentin samples, were prepared, yielding a total of 90 samples. Erosion was performed by immersing the samples in Red Bull and Red Bull light with and without green tea extract. Tap water with and without green tea extract was used as the control groups. The samples were subjected to abrasive/erosive cycling for five days. The following cycling was performed daily: toothbrush abrasion (20 brushstrokes; 2.5 N); eight erosive cycles (2 min storage in the respective solutions); in between the erosive cycles, storage in artificial saliva (60 min) and again toothbrush abrasion (20 brushstrokes; 2.5 N). During the night, samples were again stored in artificial saliva. Abrasive/erosive dentin wear was measured using a stylus profilometer (µm, accuracy = 40 nm). The measured dentin loss results from the vertical position shift on the y-axis from base to final profile after the wear process in 2D. Pairwise comparisons between the groups were carried out using Wilcoxon signed-rank test. RESULTS: The following dentin wear (median [IQR]) was measured: Red Bull: 1.9 µm (0.5); Red Bull Light: 1.3 µm (0.3); Red Bull with green tea extract: 0.8 µm (0.3); Red Bull Light with green tea extract: 0.3 µm (0.5); Tap water with green tea extract: -0.2 µm (0.7); Tap water: -1.0 µm (1.2). The comparison of all tested groups to each other proved to be statistically significant (p < 0.05). CONCLUSION: The supplementation of energy drinks with green tea extract provide a protective effect against erosive/abrasive wear in vitro.

Interaction between Hexametaphosphate, Other Active Ingredients of Toothpastes, and Erosion-Abrasion in Enamel in vitro.

Sodium hexametaphosphate (HMP) as toothpaste additive is claimed to reduce erosive tooth wear and to stabilize stannous ions. However, little is known about the impact of concentration and its interactions with fluoride (F) or stannous+fluoride ions (F/Sn) on enamel erosion and erosion-abrasion. In a 10 day cyclic in vitro erosion-abrasion model, 320 flat human enamel specimens were divided into ten groups (n = 32 each) and daily subjected to six erosive challenges (0.5% citric acid, 2 min) and two toothpaste suspension applications (2 min, 1:3 F-free toothpaste:mineral-salt solution, 0.23% sodium gluconate). Half of specimens per group were additionally brushed twice/day (200 g, 15 s) during suspension immersion. Nine suspensions contained HMP (0.25%, 1.75%, 3.25%), either on its own or combined with F (373 ppm F-) or F/Sn (800 ppm Sn2+, 373 ppm F-). One suspension contained sodium gluconate only (NegContr). After 10 days, specimens' surfaces were analysed with profilometry, energy dispersive X-ray spectroscopy, and scanning electron microscopy. Tissue loss (µm, mean ± standard deviation) in NegContr was 10.9 ± 2.0 (erosion), 22.2 ± 1.6 (erosion-abrasion). Under erosive conditions, only 0.25% HMP in any combination and 1.75% HMP with F/Sn reduced loss significantly (-28% to -54%); 3.25% HMP without F and F/Sn increased loss significantly (+35%). With additional abrasion, no suspension reduced loss significantly compared to NegContr, instead, in groups without F and F/Sn or with 3.25% HMP loss was increased (+15% to +30%). Conclusively, at higher concentrations, HMP increased erosive tooth wear and seemed to reduce anti-erosive effects of fluoride and stannous ions.

Epidemiology, aetiology and prevention of tooth wear.

Tooth wear is a commonly reported finding globally; however, many patients are unaware of having tooth wear. Identifying early signs of erosion, abrasion or attrition and determining the risk factors contributing to a patient's tooth wear may help to prevent further loss of enamel and dentine in the future. Appropriate prevention should be instigated, or appropriate referral made to other health professionals, when conditions such as gastroesophageal reflux or eating disorders are suspected. This paper presents the epidemiology and aetiological factors for tooth wear, as well as identifying the common clinical presentations of tooth wear. Patient perspectives on tooth wear and preventive techniques that can be utilised are also discussed.

Effect of fluoride group on dental erosion associated or not with abrasion in human enamel: A systematic review with network metanalysis.

OBJECTIVES: This systematic review evaluated the efficacy of monovalent and polyvalent fluoride group compared to the non-fluoride group on the prevention of enamel erosion associated or not with abrasion in in situ studies. DESIGN: This review was registered in the PROSPERO (CRD42017071118) and followed PRISMA 2020 guidelines. A systematic and comprehensive search was performed using PUBMED, WEB OF SCIENCE, SCOPUS, EMBASE, BBO, LILACS, SCIELO, and grey literature IBICT-BDTD. All in situ and ex vivo studies of erosion and erosion/abrasion tooth wear were included, with no language or date restrictions. RESULTS: 730 studies were obtained and after exclusion of duplicates, 311 were included for title and abstract reading. Two independent authors (kappa= 0.98) systematically conducted the selection phase. Considering the eligibility criteria and after full-text reading, 19 studies were included in qualitative and quantitative analysis. CONCLUSION: Network metanalysis showed that polyvalent fluoride group, especially Sn-compounded, prevented enamel wear by erosion and erosion/abrasion compared to the non-fluoride group and monovalent fluoride group. Both low and high concentration monovalent fluoride group were not able to prevent erosion wear associated or not with abrasion. Sensitivity analysis of the network metanalysis was performed with the low risk of bias studies and the results were confirmed. There is robust evidence that stannous-compounded fluoridated and titanium tetrafluoride agents are effective in preventing erosion and erosion/abrasion compared to the non-fluoride group and other interventions.

Preventive effect of chitosan gel containing CaneCPI-5 against enamel erosive wear in situ.

OBJECTIVE: This study evaluated the preventive effect of a chitosan gel containing CaneCPI-5 against enamel erosion and erosion + abrasion in situ. METHODS: Sixteen volunteers participated in a crossover, double-blind protocol, comprising 4 phases: (1) no treatment (Nt); (2) chitosan gel (Cg); (3) chitosan gel + 12,300 ppm NaF (Cg + NaF); and (4) chitosan gel + 0.1 mg/mL CaneCPI-5 (Cg + Cane). Volunteers wore an appliance containing 4 specimens. Once/day, they applied the gel (except for Nt) (4 min/specimen). Erosive challenges were performed extra-orally (0.1% citric acid, 90 s, 4 × /day; ERO). Specimens were also abraded (toothbrush, 15 s/specimen, 2 × /day; ERO + ABR). Enamel wear was assessed by profilometry and relative surface reflection intensity (%SRI). Two-way RM-ANOVA/Sidak's tests and Spearman's correlation were used (p < 0.05). RESULTS: For profilometry, ERO + ABR promoted significantly greater wear when compared with ERO. There was a significant difference among all treatments. The lowest enamel loss occurred for Cg + Cane, followed by Cg + NaF, Cg, and Nt (p < 0.05). The %SRI was significantly lower for ERO + ABR when compared to ERO, only for the Nt group. The greatest %SRI was found for the Cg + NaF and Cg + Cane groups, which did not differ significantly, regardless of the conditions. The lowest %SRI was found for the Nt and Cg groups, which did not differ from each other, regardless of the conditions. The Nt group did not differ significantly from the Cg + NaF (ERO). There was a significant correlation between both analyses. CONCLUSION: The incorporation of CaneCPI-5 in the chitosan gel prevented erosive wear in situ. CLINICAL RELEVANCE: These results open a new perspective for the use of CaneCPI-5 in other application vehicles, such as chitosan gel.

REGULAR APPLICATION OF FLUORIDES TO TEETH IS LIKELY TO PROVIDE SOME PROTECTION AGAINST ENAMEL EROSION AND ABRASION.

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION: Zanatta RF, TMF Caneppele, T Scaramucci, R El Dib, LC Maia, DM Ferreira, AB Borges Protective effect of fluorides on erosion and erosion/abrasion in enamel: a systematic review and meta-analysis of randomized in situ trials. Arch Oral Biol. 2020 Dec;120:104945. doi: 10.1016/j.archoralbio.2020.104945. Epub 2020 Oct 16. SOURCE OF FUNDING: Sao Paulo Research Foundation (grant number 2017/13799-8), National Council for Scientific and Technological Development, (grant numbers 310953/2015-4 and 310320/ 2017-8). TYPE OF STUDY/DESIGN: Systematic review with meta-analysis.

Effect of the toothbrush tuft arrangement and bristle stiffness on the abrasive dentin wear.

The geometrical properties of toothbrushes play a role in developing abrasive tooth wear and non-carious cervical lesions. This study investigated the interplay between the toothbrush tuft arrangement (crossed vs. parallel) and bristle stiffness (soft vs. medium) on the abrasive dentin wear using three slurries with different levels of abrasivity (RDA: 67, 121 and 174). Twelve groups of bovine dentin samples (n = 20) were brushed with a combination of the aforementioned variables. Abrasive dentin wear was recorded with a profilometer and the resulting abrasive wear of each group was calculated and compared with each other using two-way ANOVA and pairwise tests. Toothbrushes with parallel tuft arrangement caused statistically significantly higher dentin wear compared to crossed tuft arrangement, regardless of the abrasivity level of the used slurry and the bristle stiffness. Soft crossed tuft toothbrushes caused statistically significantly higher abrasive dentin wear than medium crossed tuft toothbrushes, while soft and medium parallel tuft toothbrushes caused the same amounts of dentin wear, regardless of the RDA value of the used slurry. These results could be helpful for dentists and dental hygienists when advising patients. Crossed tuft toothbrushes could be a less-abrasive choice in comparison to parallel tuft toothbrushes.

The effect of mouthwashes on fluoride dentifrices in preventing dental abrasion or erosion.

Erosive tooth wear (ETW) refers to the chemical dissolution of mineralized tissues by acids of non-bacterial origin. It occurs in the primary as well as the permanent dentition. In this study, our objectives were to investigate and compare the impact of chlorhexidine gluconate (CHX), essential oils (EO), and cetylpyridinium chloride (CPC) on ETW protection produced by conventional fluoride kinds of toothpaste. A clinically relevant in-vitro erosion/abrasion pH cycling model was employed to test the effect of the aforementioned mouthwashes on modulating the ability of NaF and SnF2 types of toothpaste. The mean dentin surface loss associated with NaF toothpaste was significantly lower than for the SnF2 toothpaste. On the other hand, enamel surface loss with SnF2 toothpaste was significantly lower than for the NaF toothpaste. Also, the surface loss of erosion was significantly higher when associated with abrasion than without brushing and for both enamel and dentin. There was no significant difference in the surface loss among all types of mouthwash. Commonly used types of mouthwash containing antimicrobial agents or additional fluoride do not impact fluoride toothpaste action on erosion/abrasion. Also, considering erosion only, the tested SnF2 dentifrice provided better protection against surface loss of enamel than the other.

Hesperidin reduces dentin wear after erosion and erosion/abrasion cycling in vitro.

OBJECTIVE: To evaluate the action of hesperidin (HPN) at different concentrations to prevent dentin erosive wear, associated or not to abrasion. METHODS: A study with 6 experimental groups (n = 10) for erosion (experiment 1) and another 6 for erosion + abrasion (experiment 2). The treatments were: distilled water (DW), DW with collagenase (DW + Col), 0.46% epigallocatechin-3-gallate (EGCG) and 0.1%, 0.5% or 1% HPN. The specimens were submitted to a cycle (3x/day) for 5 days that consisted of immersion on 1% citric acid (5 min), artificial saliva (60 min), treatment (5 min), brushing (150 movements only in experiment 2), and artificial saliva (60 min / overnight). Collagenase was added in artificial saliva for all groups except DW-group. Dentin changes were assessed with optical profilometry and scanning electron microscopy. Data were submitted to one-way analysis of variance and Tukey tests (α = 0.05). RESULTS: For experiment 1, DW showed the lowest wear and did not significantly differ from EGCG. DW + Col showed the highest wear, being significantly different from HPN at 1%. In experiment 2, DW showed the lowest wear and DW + Col the highest. EGCG showed less wear than the three groups treated with HPN. In addition, for both cycling models, there were no significant differences among the three concentrations of HPN analyzed. In micrographs of HPN-treated groups, it could be observed the formation of a barrier on the dentin that promoted the obliteration of the tubules. CONCLUSIONS: HPN was able to preserve the demineralized organic matrix layer but did not overcome the effect of EGCG.

Impact of mucin on the anti-erosive/anti-abrasive efficacy of chitosan and/or F/Sn in enamel in vitro.

The application of stannous ions in combination with fluoride (F/Sn) is one of the central strategies in reducing erosive tooth wear. F/Sn efficacy can be enhanced by adding chitosan, a positively charged biopolymer. For patients with low saliva flow, this efficacy, however, is not sufficient, making further improvement desirable. This could be achieved by combining chitosan with other molecules like mucin, which together might form multilayers. This in-vitro study aimed to investigate the effect of chitosan, mucin, F/Sn and combinations thereof on enamel erosion and erosion-abrasion. Human enamel samples (n = 448, 28 groups) were cyclically eroded or eroded-abraded (10 days; 6 × 2 min erosion and 2 × 15 s/200 g abrasion per day). Samples were treated 2 × 2 min/day with solutions containing either, chitosan (50 or 500 mPas), porcine gastric mucin, F/Sn or combinations thereof after abrasive challenge. Tissue loss was measured profilometrically, interaction between hard tissue and active agents was assessed with energy dispersive spectroscopy and scanning electron microscopy. Chitosan and F/Sn showed the expected effect in reducing tissue loss under erosive and under erosive-abrasive conditions. Neither mucin alone nor the combinations with mucin showed any additional beneficial effect.

Interplay between different manual toothbrushes and brushing loads on erosive tooth wear.

OBJECTIVE: To investigate the effect of different types of manual toothbrushes and brushing loads on the progression of erosive tooth wear (ETW) on enamel. METHODS: Bovine enamel specimens (n = 10) were submitted to a 5-day erosive-abrasive cycling model (0.3 % citric acid for 5 min, artificial saliva for 60 min, 4x/day). Toothbrushing was carried out 2x/day for 15 s, according to the toothbrushes tested (ultra-soft (a): Curaprox 5460; ultra-soft (b): Sensodyne Repair & Protect; soft (a): Colgate Slim Soft; soft (b): Oral-B Indicator Plus; medium: Johnson's Professional; hard: Tek) and brushing loads (1.5 N, 3 N). Surface loss (SL, in µm) was assessed by optical profilometry on conclusion of the cycling. Some of the toothbrush characteristics were evaluated. Data were statistically analyzed (α = 0.05). RESULTS: For the 1.5 N load, the hard brush showed the highest SL value, with statistical significance. The other toothbrushes did not differ significantly, except that ultra-soft (a) caused significantly higher SL than ultra-soft (b). For the 3 N load, hard and soft (a) exhibited the highest SL. Soft (b) and medium had the lowest SL value, with statistical significance. Only soft (a) and ultra-soft (b) showed significant difference between loads, with lower SL for the load of 1.5 N. None of the toothbrush characteristics were significantly correlated with SL. CONCLUSIONS: Although different degrees of enamel surface loss were observed with use of the different toothbrushes, no association was found between the toothbrush characteristics and SL. Depending on the toothbrush, the force of brushing was capable of modulating the ETW of enamel. Based on the brushing loads usually applied by healthy individuals, hard brushes are not recommended for use by patients with ETW. CLINICAL SIGNIFICANCE: The use of hard bristle brushes is not recommended for use by individuals who exert healthy forces when brushing their teeth. The toothbrush characteristics are of secondary importance in terms of causing enamel loss in ETW.

In vitro effect of children's toothpaste on brushing abrasion of eroded primary enamel.

PURPOSE: Emerging data have suggested that acid erosion has become an increasing clinical problem in pediatric dentistry. This study aimed to investigate the abrasive effects of two commercial toothpastes on primary enamel eroded by orange juice using an in vitro model. METHODS: Thirty enamel slabs were obtained from primary teeth and then randomly assigned to three groups (n = 8) comprising two different toothpastes: G1-control-distilled water; G2-Dentifrice A (containing no fluoride); and G3-Dentifrice B (1.100 ppmF-NaF). Each slab had one half protected to provide a control side, and the other one was subjected to treatments. The slabs were submitted to daily erosive challenges (3×/day, 2 min) in concentrated orange juice (pH 3.38) associated with abrasive challenges using a tooth-brushing machine (150 brush movements for each cycle). During the experimental period, the slabs were kept in 37 °C artificial saliva, and the experiment was carried out for 5 days. The depths of the resulting eroded areas were measured by stylus profilometry. The data were analyzed using ANOVA and the Tukey-Kramer test (α = 5%). RESULTS: Tooth loss (µm, mean ± SD) was 2.46 ± 1.18 for G1, 3.32 ± 2.12 for G2 and 2.14 ± 1.03 for G3. Therefore, the NaF dentifrice (Dentifrice B) produced significantly less mineral loss (p = 0.04) than dentifrice A. CONCLUSIONS: The findings suggest that fluoride toothpaste could protect primary enamel against erosion.

The Addition of Propylene Glycol Alginate to a Fluoride Solution to Control Enamel Wear: An in situ Study.

The aim of this study was to evaluate the protective effect of propylene glycol alginate (PGA) associated with sodium fluoride (NaF) against enamel erosion and erosion-abrasion. A 4-phase, split-mouth, double-blind, crossover in situ trial was conducted with the following solutions: F + PGA (225 ppm F- + 0.1% PGA), F (225 ppm F-), F + Sn (225 ppm F- + SnCl2, 800 ppm Sn2+), and negative control (distilled water). In each phase, 12 subjects wore removable mandibular appliances containing 4 enamel specimens, which were submitted either to erosion or to erosion-abrasion challenges for 5 days. Acquired salivary pellicle was formed in situ for 2 h. Erosion-abrasion consisted of acid challenge (1% citric acid solution, pH 2.3, 5 min, 4×/day), exposure to saliva in situ (2 h, 4×/day), brushing (5 s, total 2 min exposure to the slurry), and treatment with the solutions (2 min, 2×/day). For erosion, the same procedures were performed, without brushing. At the end, surface loss (SL; in µm) was evaluated by means of optical profilometry. KOH-soluble fluoride was quantified for erosion-only groups using extra specimens. For both challenges, the SL values found for F + PGA did not differ significantly from those of F and the negative control, and the SL value shown for F + Sn was significantly the lowest. Erosion-abrasion promoted significantly higher SL values than erosion. KOH-soluble fluoride analysis showed that F + Sn had a higher fluoride concentration in comparison with the negative control and F, while F + PGA did not differ from any of the other groups. In conclusion, PGA was not able to improve the protective effect of NaF against erosive enamel wear.