Acquired pellicle and biofilm engineering with CaneCPI-5: Insights from proteomic and microbiomics analysis.

OBJECTIVE: In this in vivo proof-of-concept study, acquired pellicle engineering was implemented to promote alterations in the protein composition of the acquired enamel pellicle (AEP) and the bacterial composition of the dental biofilm after treatment with Sugarcane cystatin (CaneCPI-5). DESIGN: After prophylaxis, 10 volunteers rinsed (10 mL, 1 min) with the following solutions: 1) deionized water (H2O- negative control or 2) 0.1 mg/mL CaneCPI-5. The AEP and biofilm were formed along 2 or 3 h, respectively. The AEP was collected with electrode filter papers soaked in 3 % citric acid. After protein extraction, samples were analyzed by quantitative shotgun label-free proteomics. The biofilm microbiome was collected with a dental curette. The DNA was extracted, amplified, and analyzed by 16S-rRNA Next Generation Sequencing (NGS). RESULTS: Treatment with CaneCPI-5 increased several proteins with antimicrobial, acid-resistance, affinity for hydroxyapatite, structural and calcium binding properties, such as Cysteine-rich-3 (6-fold-p = 0.03), Cystatin-B (5.5-fold-p < 0.01), Neutrophil-defensin 1 (4.7-fold-p < 0.01), Mucin (3.9-fold-p < 0.01), Immunoglobulin-heavy-constant (3.8-fold-p < 0.01) and Lactotransferrin (2.8-fold-p < 0.01). Microbiome revealed that several commensal bacteria had their abundance increased after rinsing with CaneCPI-5, such as Corynebacterium and Neisseria, while Streptococcus and Prevotella nigrescens were decreased. The results indicate the efficiency of CaneCPI-5 in promoting beneficial changes in the AEP and biofilm, making this phytocystatin a potential target for incorporation into dental products. CONCLUSION: Cane demonstrated the capability to alter the protein composition of the acquired enamel pellicle (AEP) and the initial colonizers of the biofilm, enhancing the presence of proteins and bacteria crucial for dental protection.

Acquired enamel pellicle and biofilm engineering with a combination of acid-resistant proteins (CaneCPI-5, StN15, and Hemoglobin) for enhanced protection against dental caries - in vivo and in vitro investigations.

OBJECTIVE: This study was designed in two-legs. In the in vivo, we explored the potential of a rinse solution containing a combination (Comb) of 0.1 mg/mL CaneCPI-5 (sugarcane-derive cystatin), 1.88 × 10- 5M StN15 (statherin-derived peptide) and 1.0 mg/mL hemoglobin (Hb) to change the protein profile of the acquired enamel pellicle(AEP) and the microbiome of the enamel biofilm. The in vitro, was designed to reveal the effects of Comb on the viability and bacterial composition of the microcosm biofilm, as well as on enamel demineralization. MATERIALS AND METHODS: In vivo study, 10 participants rinsed (10mL,1 min) with either deionized water (H2O-control) or Comb. AEP and biofilm were collected after 2 and 3 h, respectively, after rinsing. AEP samples underwent proteomics analysis, while biofilm microbiome was assessed via 16 S-rRNA Next Generation Sequencing(NGS). In vitro study, a microcosm biofilm protocol was employed. Ninety-six enamel specimens were treated with: 1)Phosphate-Buffered Solution-PBS(negative-control), 2)0.12%Chlorhexidine, 3)500ppmNaF and 4)Comb. Resazurin, colony-forming-units(CFU) and Transversal Microradiography(TMR) were performed. RESULTS: The proteomic results revealed higher quantity of proteins in the Comb compared to control associated with immune system response and oral microbial adhesion. Microbiome showed a significant increase in bacteria linked to a healthy microbiota, in the Comb group. In the in vitro study, Comb group was only efficient in reducing mineral-loss and lesion-depth compared to the PBS. CONCLUSIONS: The AEP modification altered the subsequent layers, affecting the initial process of bacterial adhesion of pathogenic and commensal bacteria, as well as enamel demineralization. CLINICAL RELEVANCE: Comb group shows promise in shaping oral health by potentially introducing innovative approaches to prevent enamel demineralization and deter tooth decay.

The stamp technique for direct restoration in a ICDAS 4 carious lesion: A 4-year follow-up.

OBJECTIVE: This case report described the use of a stamping technique associated with a bulk fill composite to restore an ICDAS 4 carious lesion on a posterior tooth. The 4-year follow-up is also presented. CLINICAL CONSIDERATIONS: A 32-year-old patient presented a carious lesion on tooth 36 with an underlying dark shadow at the dentin seen from the noncavitated enamel occlusal surface, which was compatible with an ICDAS 4 carious lesion. The lesion was radiographically detected and the caries disease was treated with dietary and hygiene habits orientations. Before accessing the lesion and selectively removing the carious tissue, an occlusal stamp was made by applying a flowable resin composite to copy the anatomy of the noncavitated enamel surface. The cavity was restored using a bulk fill resin composite (Opus Bulk Fill, FGM) with 4-mm-thick increments. Before curing the last increment, a Teflon band was adapted at the uncured bulk fill composite surface and the occlusal stamp made with the flowable composite was pressed against it to reproduce the natural characteristics and initial occlusal anatomy. The top surface was light-activated for 40 s. After 4 years, small wear could be seen in the restoration, but still within clinically acceptable levels. CONCLUSION: The occlusal stamp technique allows reproduction of the natural anatomy of teeth affected by ICDAS 4 carious lesions with good clinical longevity over 4 years. CLINICAL SIGNIFICANCE: This case report presents the use of the stamp technique to restore a tooth affected by an ICDAS 4 lesion, in which a carious process reached the dentin and the enamel anatomy was still preserved. The bulk fill resin composite associated with the occlusal stamp was chosen to quickly restore the cavity with clinical predictability. Bulk fill composites allow the insertion of up to 4-mm-thick increments and offer lower shrinkage stress, good clinical longevity and a less time-consuming procedure in cases of posterior teeth, especially if associated with the stamp technique.

The in vitro Effect of Dentifrices With Activated Charcoal on Eroded Teeth.

AIM: The objective of this research was to compare the abrasive potential of dentifrices containing activated charcoal with those of a conventional dentifrice on the development of erosive tooth wear (ETW) in vitro. METHODS: Enamel and dentin samples were divided into toothpastes (n = 12): group (G)1-Colgate Triple Action (1450 ppm F) (positive control); G2-Colgate Natural Extracts (1450 ppm F); G3-Colgate Luminous White Activated Carbon (1450 ppm F); G4-Oral-B Whitening Therapy Charcoal (1100 ppm F); G5-Oral-B 3D White Mineral Clean (1100 ppm F); G6-Curaprox Black Is White (950 ppm F); and G7-erosion only (no abrasion, negative control). All samples were submitted to erosive pH cycles and G1 to G6 to abrasive challenges (15 seconds) using toothpastes' slurries plus 45 seconds of treatment for 7 days. The final profile was overlaid to the baseline one for the ETW calculation (µm). The data were subjected to analysis of variance/Tukey or Kruskal-Wallis/Dunn tests (P < .05). RESULTS: Oral-B 3D White (13.0 ± 1.0, 9.37 [1.36] µm), Oral-B Whitening Therapy (15.1 ± 1.2, 8.58 [1.71] µm), and Colgate Luminous White (13.6 ± 1.0, 7.46 [0.94] µm) toothpastes promoted the greatest enamel and dentin wear. On the other hand, Colgate Triple Action (12.2 ± 1.2, 5.30 [1.26] µm), Colgate Natural Extracts (10.8 ± 1.1, 4.16 [1.11] µm), and Curaprox Black Is White (11.5 ± 1.5, 4.06 [0.92] µm) toothpastes promoted lower wear values, similar to erosion only (4.16 [0.94] µm) in the case of dentin but not enamel (7.1 ± 0.8 µm). CONCLUSIONS: Toothpastes containing charcoal combined with pyrophosphate may have a high abrasive effect on eroded tooth surfaces. Many patients influenced by digital marketing use toothpastes containing activated charcoal with the aim of bleaching their teeth. However, care should be taken when using these products, as they may have a high abrasive effect.

Effect of a Toothpaste Containing Surface Pre-Reacted Glass-Ionomer Filler on the Remineralization of Artificial Carious Enamel Lesions in situ.

This study evaluated the remineralizing effect of a toothpaste containing surface pre-reacted glass-ionomer (S-PRG) filler on demineralized enamel in situ. For this, 180 bovine enamel samples were demineralized by using a microcosm biofilm model for 3 days. Thereafter, the samples were randomly signed to 15 healthy volunteers and to 3 cross-over in situ phases corresponding to the following treatments: (1) toothpaste containing 1,500 ppm F as NaMFP (positive control, Colgate®Cavity Protection), (2) toothpaste containing 5% S-PRG filler (Shofu®), and (3) placebo toothpaste (negative control prepared by Shofu®). Four demineralized enamel blocks were fixed into each palatal appliance per phase. The volunteers wore the appliances for 5 days and were trained to brush their teeth 2 times for 2 min a day, while one drop of the toothpaste's slurry (1:3) was dripped on each sample for the same period. The surface hardness and TMR analyses were done and analyzed by ANOVA/Tukey and t test (p < 0.05). S-PRG filler and Colgate® toothpastes were equally able to improve 2-2.5× enamel remineralization by the analysis of % surface hardness recovery. However, S-PRG toothpaste was the only one able to significantly improve ΔΔZ (the integrated mineral loss recovery: 1,489 ± 503 %vol.µm) compared to placebo (1,050 ± 467 %vol.µm), while Colgate® did not differ from placebo. No differences were seen between the groups with respect to ΔLD. S-PRG filler and Colgate® toothpastes show similar potential to remineralize the lesion surface. However, S-PRG toothpaste is better to recover mineral loss at the subsurface area.

Is deoxycholic acid able to reduce submental fat and increase patient satisfaction when compared to placebo groups? A systematic review.

The accumulation of submental fat (SMF) can negatively impact facial harmony appearance, and one alternative treatment for this condition is the application of deoxycholic acid (DOC). The objective of this systematic review was to answer the following question: "Is DOC able to reduce SMF and increase patient satisfaction when compared to the placebo groups?". Therefore, a detailed search strategy was carried out in 6 scientific databases (PubMed, Scopus, Embase, Lilacs, SciELO, and Web of Science) as primary search sources, while OpenGrey and OpenThesis were also used to capture the "grey literature". Only six studies met all inclusion criteria and were considered in this review analysis. The selected sample included prospective clinical studies published from 2014 to 2018, covering a total sample of 3488 patients, with an average age ranging from 46 to 49.5 years old. All selected articles evaluated the effect of DOC at concentrations of 1 mg/cm² or 2 mg/cm², using saline or placebo as control solutions for the comparative analysis. The application interval was 28 days in all studies analyzed, and the treatment duration ranged from 4 to 6 weeks. In all studies evaluated, there was a reduction in SMF and patient satisfaction with the application of DOC was higher than in the control groups at the end of a 12-week period. Thus, it is possible to conclude that the application of DOC has a positive effect on reducing SMF and improving patient satisfaction concerning their facial appearance.

The protective effect of the experimental TiF4 and chitosan toothpaste on erosive tooth wear in vitro.

This study evaluated the protective effect of TiF4 and chitosan toothpaste on erosive tooth wear (ETW) in vitro. Enamel and dentin samples were randomly assigned to toothpastes (n = 12): (G1) TiF4 (1400 ppm F-), (G2) 0.5% chitosan (75% deacetylation, 500 mPas), (G3) TiF4 (1400 ppm F-) plus 0.5% chitosan (75% deacetylation, 500 mPas), (G4) Placebo, (G5) Erosion Protection (Elmex-GABA, 1400 ppm F-). Twelve samples were only eroded. All samples were submitted to erosive pH cycles and G1 to G5 to abrasive challenges using toothpastes' slurries plus 45 s of treatment, for 7 days. The final profile was overlaid to the baseline one for the ETW calculation (µm). The data were subjected to Kruskal-Wallis/Dunn tests. TiF4 toothpastes, regardless of the presence of chitosan, were able to significantly reduce ETW compared to placebo, while chitosan alone was similar to placebo for both tissues. The toothpastes containing TiF4 were even superior to the commercial Elmex toothpaste on enamel, while they were similar on dentin; both were also significantly different from placebo for both tissues. TiF4 and Elmex toothpastes minimized the impact of brushing on eroded surface. In conclusion, TiF4 toothpastes, regardless the presence of chitosan, showed to be effective in minimizing ETW in vitro.

Effect of TiF4/NaF and chitosan solutions on biofilm formation and prevention of dentin demineralization.

OBJECTIVE: This study evaluated the effect of experimental solutions containing TiF4/NaF and chitosan on bacterial species of microcosm biofilm and on dentin demineralization. DESIGN: Microcosm biofilm was produced from human saliva mixed with McBain medium (0.2% sucrose) on bovine dentin for 5 days, under 5% CO2 and 37 °C. From the 2nd day to 5th day, the treatments were applied (1×60s/day) as following: (1) NaF (500 ppm F-, positive control); (2) TiF4 and NaF (TiF4: 190 ppm Ti4+ and 300 ppm F-; NaF: 190 ppm F-); (3) similar to 2 plus 0.5% chitosan (Ch 500 mPa.s, 75% deacetylation); (4) phosphate buffer solution (negative control); and (5) 0.5% chitosan (Ch 500 mPa.s, 75% deacetylation). CFU counting was performed for total microorganism, total streptococci, total lactobacilli and mutans streptococci. Dentin demineralization was measured by transverse microradiography-TMR. The data were compared using ANOVA/Tukey or Kruskal-Wallis/Dunn tests (p < 0.05). RESULTS: No differences were found between the treatments with respect to CFU counting (p > 0.05). Dentin treated with TiF4/NaF plus chitosan solution presented the lowest demineralization compared to the negative control and pure chitosan solution. On the other hand, this experimental solution did not significantly differ from TiF4/NaF solution, being both able to significantly reduce mineral loss. CONCLUSION: TiF4/NaF plus chitosan solution, at suitable pH to be clinically applicable, had no antimicrobial effect, but it was able to reduce dentin caries development under this model.

Effect of TiF4/NaF and chitosan solutions on the development of enamel caries under a microcosm biofilm model.

OBJECTIVES: To evaluate the effect of experimental solutions containing TiF4/NaF and chitosan on bacterial species and on enamel caries prevention. METHODS: Microcosm biofilm was produced from human saliva mixed with McBain saliva (0.2% sucrose) on bovine enamel for five days, under 5% CO2 and 37 °C. From the second day until the end, the treatments were applied (1 × 60 s/day): (1) NaF (500 ppm F-, positive control); (2) TiF4 and NaF (TiF4: 190 ppm Ti4+ and 300 ppm F-; NaF: 190 ppm F-); (3) similar to 2 plus 0.5% chitosan (Ch 500 mPas, 75% deacetylation); (4) phosphate buffer solution (negative control); and (5) 0.5% chitosan (Ch 500 mPas, 75% deacetylation). CFU counting was performed for total microorganism, total streptococcus, total lactobacillus and Streptococcus mutans. Enamel demineralization was measured by transverse microradiography-TMR. The data were compared using ANOVA/Tukey or Kruskal-Wallis/Dunn tests (p < .050). RESULTS: No differences were found between the treatments with respect to CFU counting (ANOVA, p > .050). Enamel treated with TiF4/NaF plus chitosan solution presented the lowest demineralization compared to the negative control and pure chitosan solution. On the other hand, this experimental solution did not significantly differ from TiF4/NaF and NaF solutions, being all of them able to significantly reduce mineral loss (50-74%), but only TiF4/NaF plus chitosan reduced lesion depth (55%) compared to the negative control (p = .001). CONCLUSION: TiF4/NaF plus chitosan solution had no antimicrobial effect, but it was able to reduce enamel caries development in 79% compared to control under this model. CLINICAL SIGNIFICANCE: This study showed that TiF4/NaF plus chitosan solution had no antimicrobial effect, but it was able to reduce enamel caries development under a microcosm biofilm model.

Effect of TiF4 varnish after pre-treatment with proanthocyanidin or chlorhexidine on the progression of erosive dentin loss in the presence or absence of the demineralized organic matrix.

This study evaluated the protective effect of TiF4 varnish, after pre-treatment with proantocyanidin or chlorhexidine, on the progression of erosive dentin loss (EDL), under the presence or absence of the demineralized organic matrix (DOM). Bovine root dentin samples were eroded for 30 min (0.1% citric acid, pH 2.5) and the loss was measured by profilometry. Half of them were subjected to the DOM removal using collagenase for 4 days, while the other half remained immersed in water. The removal of DOM was checked by profilometry. Samples were divided into 24 groups (n = 15) according to the factors: 1- With or without DOM; 2- Pre-treatment with 0.012% chlorhexidine gel, 10% proanthocyanidin gel or untreated for 1 min; 3-Final Treatment with TiF4 varnish, NaF varnish, placebo varnish or untreated for 6 h. The samples were submitted to a pH cycling for 5 days: 0.1% citric acid (4 × 90s/day) and artificial saliva between the challenges. The final profile was obtained for the calculation of EDL (µm, three-way ANOVA/Tukey test). When DOM was preserved, the EDL was lower compared to the condition without DOM (7.08 ± 4.03 µm and 9.80 ± 3.79 µm, p < 0.001, respectively), regardless of the treatments. The pre-treatment had no influence on the progression of EDL (p = 0.637), while the final treatment (TiF4 varnish only, 6.77 ± 4.08 µm) was effective in reducing the progression of EDL (NaF varnish: 9.52 ± 4.02 µm; Placebo varnish: 8.64 ± 4.06 µm and no treatment: 8.80 ± 3.95 µm). It can be concluded that DOM has important protective effect on the progression of EDL. TiF4 was the unique treatment capable of reducing EDL progression, regardless of the pre-treatment of DOM.

Effect of different citrus sweets on the development of enamel erosion in vitro.

The increased consumption of citrus sweets can contribute to the development of erosive tooth wear (ETW). Objective This in vitro study evaluated the erosive potential of citrus sweets on bovine enamel samples regarding the quantification of wear. Methodology Ninety bovine crowns were prepared and samples were randomly distributed into 6 groups (n=15): 0.1% citric acid solution (pH 2.5); Coca-Cola ® Soft Drink (pH 2.6); Fini ® Diet (lactic and citric acid, pH 3.3); Fini ® Jelly Kisses (lactic and citric acid, pH 3.5); Fini ® Fruit Salad Bubblegum (maleic acid, pH 2.6); Fini ® Regaliz Acid Tubes (maleic and citric acid, pH 3.1). Sweets were dissolved in the proportion of 40 g/250 mL of deionized water. Enamel samples were submitted to erosive challenges for 7 days (4 daily acid immersion cycles for 90 s each). Enamel wear was measured using contact profilometry (µm), and data (median values [interquartile range]) were submitted to Kruskal-Wallis/Dunn's test (p<0.0001). Results All citrus sweets tested present a high erosive potential, Fini Diet ® (2.4 [1.2]) and Fini Regaliz Tubs ® (2.2 [0.5]) show the highest erosive potential, similar to 0.1% citric acid (2.3 [0.7]); Fini Regaliz Tubs ® is more erosive than Coca-Cola ® (1.4 [0.9]). Conclusion The evaluated citrus sweets have great erosive potential and play a key role in the development of ETW.

Structural, chemical and optical characterizations of an experimental SiO2-Y-TZP ceramic produced by the uniaxial/isostatic pressing technique.

This study aimed to produce a new SiO2+Y-TZP ceramic via uniaxial/isostatic compression that was structurally and chemically characterized relating to its translucency and flexural strength. SiO2 and Y-TZP were mixed using a ball mill, pressed and sintered at 1150 °C. The optical and mechanical properties of the specimens were compared to lithium disilicate (LD) and zirconia-reinforced lithium silicate (ZLS) (Kruskal-Wallis, α = 0.05). The Fourier Transform Infrared Spectroscopy bands suggested an interaction between Si, O and Zr. Contrast ratio and translucency parameter of the experimental ceramic were higher and lower, (p = 0.000001) respectively, than those of the LD and ZLS. The experimental ceramic presented similar flexural strength to ZLS, but lower than LD (p < 0.0001). It can be concluded that this processing method is efficient to obtain a SiO2+Y-TZP ceramic and 1150 °C crystallizes SiO2 without inducing t-m transformation. The SiO2+Y-TZP ceramic presented lower translucency and higher masking ability than the commercially available glass-ceramics, but similar flexural strength to one glass-ceramics.

The effect of commercial whitening toothpastes on erosive dentin wear in vitro.

OBJECTIVES: This study evaluated the erosive tooth wear promoted by commercial whitening toothpastes on eroded dentin in vitro. DESIGN: Ninety bovine roots were embedded, polished and subjected to the baseline profile analysis. The samples were protected in 2/3 of the dentin surface and were randomly assigned to 6 groups (n = 15/group): Oral-B 3D White; Close-up Diamond Attraction Power White; Sorriso Xtreme White 4D; Colgate Luminous White; Crest and erosion only. All samples were submitted to erosive pH cycles (4 × 90 s in 0.1% citric acid, pH 2.5, per day) and abrasive challenges (2 × 15 s, per day) for 7 days. The samples were subjected to abrasion, using toothbrushing machine, soft toothbrushes and slurries of the tested toothpastes (1.5 N, 1:3 water). Between the challenges, the samples were immersed in artificial saliva. The final profile was overlaid to the baseline profile for the calculation of the erosive dentin wear (µm). The data were subjected to Kruskal-Wallis/Dunn tests (p < 0.05). RESULTS: Colgate Luminous White (4.7 µm) and Sorriso Xtreme White 4D (4.0 µm) promoted the highest wear, similarly to Oral-B 3D White (2.3 µm). Oral-B 3D White promoted similar wear compared to Crest (1.1 µm) and Close-up Diamond Attraction Power White (1.2 µm); however, it induced significant higher dentin wear compared to erosion only (1.0 µm). Close-up Diamond Attraction Power White and Crest did not increase the erosive wear compared to erosion only. CONCLUSION: Some whitening toothpastes increase the wear of eroded dentin, which should be considered by the dentist when prescribing them to patient with root exposure.

Effect of different citrus sweets on the development of enamel erosion in vitro

Abstract The increased consumption of citrus sweets can contribute to the development of erosive tooth wear (ETW). Objective This in vitro study evaluated the erosive potential of citrus sweets on bovine enamel samples regarding the quantification of wear. Methodology Ninety bovine crowns were prepared and samples were randomly distributed into 6 groups (n=15): 0.1% citric acid solution (pH 2.5); Coca-Cola ® Soft Drink (pH 2.6); Fini ® Diet (lactic and citric acid, pH 3.3); Fini ® Jelly Kisses (lactic and citric acid, pH 3.5); Fini ® Fruit Salad Bubblegum (maleic acid, pH 2.6); Fini ® Regaliz Acid Tubes (maleic and citric acid, pH 3.1). Sweets were dissolved in the proportion of 40 g/250 mL of deionized water. Enamel samples were submitted to erosive challenges for 7 days (4 daily acid immersion cycles for 90 s each). Enamel wear was measured using contact profilometry (μm), and data (median values [interquartile range]) were submitted to Kruskal-Wallis/Dunn's test (p<0.0001). Results All citrus sweets tested present a high erosive potential, Fini Diet ® (2.4 [1.2]) and Fini Regaliz Tubs ® (2.2 [0.5]) show the highest erosive potential, similar to 0.1% citric acid (2.3 [0.7]); Fini Regaliz Tubs ® is more erosive than Coca-Cola ® (1.4 [0.9]). Conclusion The evaluated citrus sweets have great erosive potential and play a key role in the development of ETW.

The Impact of the Demineralized Organic Matrix on the Effect of TiF4 Varnish on the Progression of Dentin Erosive Loss.

This in vitro study compared the effect of TiF4 varnish with that of NaF varnish, applied on pre-eroded bovine dentin samples, with respect to the progression of erosive loss, in the presence or absence of the demineralized organic matrix (DOM). One hundred and sixty bovine dentin samples were pre-eroded (0.1% citric acid, pH 2.5, 30 min). Half of the samples were subjected to the DOM removal (collagenase solution, 5 days). Samples with and without the DOM were treated according to the groups (n = 20 with DOM and 20 without DOM/group): TiF4 varnish (2.45% F), NaF varnish (2.45% F), placebo varnish (without fluoride) and control (no treatment). Thereafter, the treated samples were submitted to erosive challenges 4 × 90 s/day (0.1% citric acid, pH 2.5) during 7 days. Between the challenges, the samples were immersed in artificial saliva. The dentin erosive loss was measured using contact profilometry (µm, n = 15). Five dentin samples per group were prepared for energy-dispersive X-ray spectroscopy analysis. Data were compared using 2-way ANOVA/Bonferroni test (p < 0.05). Both fluoride varnishes were effective in reducing the erosive loss progression regardless of the dentin condition when compared to placebo varnish and control groups. Despite the fact that the TiF4 varnish was more effective than the NaF varnish for both dentin conditions (p < 0.001), its effect was significantly reduced in the absence of DOM (p < 0.05). It can be concluded that the TiF4 varnish is the best treatment in reducing the progression of dentin erosive loss (100%) in vitro, but its protective effect is more pronounced in the presence of DOM.

Effect of an Experimental Paste with Hydroxyapatite Nanoparticles and Fluoride on Dental Demineralisation and Remineralisation in situ.

This study evaluated the effect of an experimental paste containing hydroxyapatite in nanoparticles (nano-HA)/fluoride on dental de-remineralisation in situ. Thirteen subjects took part in this crossover/randomised/double-blind study performed in 4 phases (14 days each). Four sound and 4 pre-demineralised specimens were worn intraorally at each phase corresponding to the following treatments: Nanop Plus (10% HA, 0.2% NaF, nano-HA/fluoride), MI Paste Plus (casein phosphopeptide-amorphous calcium phosphate, 0.2% NaF), F (0.2% NaF) and placebo. Two-hundred and forty enamel and 240 dentine specimens were selected by using surface microhardness; half of them were subjected to pre-demineralisation and the other half remained sound. Sound specimens were further exposed to severe cariogenic challenge (20% sucrose in biofilm) in situ, while pre-demineralised specimens were not. All specimens were exposed to fluoride dentifrice slurry 2×1 min/day. Thereafter, the treatments were done for 4 min. The de-remineralisation was quantified by transversal microradiography. The data were statistically analysed by repeated-measures ANOVA/Tukey's tests (p<0.05). Generally, no huge differences were found among the treatments. However, Nanop Plus was the only treatment able to significantly reduce dentine demineralisation (x0394;Z, integrated mineral loss) and to improve enamel remineralisation (x0394;x0394;Z, integrated mineral uptake) compared to placebo. No treatments were able to reduce enamel demineralisation, while for dentine remineralisation all treatments were similarly effective in improving x0394;x0394;Z compared to placebo. Nanop Plus seems to have a positive influence on dental de-remineralisation, which should be further confirmed.