In vitro effect of fluoride gels supplemented with nano-sized sodium trimetaphosphate on enamel erosive wear.

OBJECTIVE: To assess the protective effect of fluoride (F) gels supplemented with micrometric or nano-sized sodium trimetaphosphate (TMPmicro and TMPnano, respectively) against enamel erosion in vitro. METHODS: Bovine enamel blocks (n = 140) were selected according to their surface hardness, and randomly divided into seven groups (n = 20/group), according to the gels tested: Placebo (without F/TMP), 4,500 µg F/g (4500F), 9,000 µg F/g (9000F), 4500F plus 2.5 % TMPnano (2.5 % Nano), 4500F plus 5 % TMPnano (5 % Nano), 4500F plus 5 % TMPnano (Micro 5 %) and 12,300 µg F/g (Acid gel). Blocks were treated once during one minute with the gels, and submitted to erosive (ERO, n = 10/group) or erosive plus abrasive (ERO+ABR, n = 10/group) challenges 4 times/day, for 90 s for each challenge (under reciprocating agitation), during consecutive 5 days. Blocks were analyzed by profilometry, and by surface (SH) and cross-sectional hardness (∆KHN). Data were submitted to two-way ANOVA, and Fisher's LSD test (p < 0.05). RESULTS: For ERO, both TMPnano-containing gels promoted enamel wear significantly lower than Placebo and 4500F, reaching levels similar to both positive controls (9000F and acid gel); significantly lower softening was observed for enamel treated with 4500F+5 % Micro and 4500F+2.5 % Nano. Also, the lowest ∆KHN values were observed for 4500F+2.5 % TMPnano among the TMP-containing gels. For ERO+ABR, the lowest enamel wear was achieved by the use of 4500F+5 % Nano among all gels, including both positive controls; lower softening was observed for Placebo and 9000F groups. CONCLUSION: The addition of 5 % nano-sized TMP to a low-fluoride gel produced superior protective effects for enamel under both challenges conditions, when compared with micrometric TMP, reaching values similar to or superior than both positive controls, respectively for ERO and ERO+ABR. CLINICAL SIGNIFICANCE: The supplementation of low-F gels with TMP was shown to significantly improve their effects on enamel erosive wear, and the use of nano-sized TMP further enhances this protective action.

The use of mouthwash containing trimetaphosphate as an adjunct therapy to fluoridated toothpaste reduces enamel demineralization.

INTRODUCTION: The decline in dental caries has been attributed to the widespread use of fluoride (F). Two forms of presentation are fluoridated toothpaste (FT) and mouthwash (MW), widely used by the population. MATERIALS AND METHODS: This study aimed to evaluate in vitro the effects of combining FT and MW, whether supplemented with sodium trimetaphosphate (TMP) or not, on dental enamel demineralization. Bovine enamel blocks (n = 60) were selected based on initial surface hardness (SHi) and divided into 5 experimental groups (n = 12 each): I) Placebo Toothpaste (without F/TMP); II) 1100 ppm F Toothpaste (FT); III) 1100F associated with a MW at 100 ppm F (FT + MW 100F); IV) 1100F associated with a MW at 225 ppm F (FT + MW 250F); and V) 1100F associated with a MW at 100 ppm F supplemented with 0.4 % TMP (FT + MW 100F-TMP). The blocks were treated twice a day, undergoing 5 pH cycles over 7 days. Thus, the percentage change in surface hardness (%SH), integrated subsurface hardness loss (ΔKHN), and the concentration of F, phosphorus (P), and calcium (Ca) in the enamel were determined. The data were submitted to ANOVA and Student-Newman-Keuls test (p < 0.001). RESULTS: The 1100F group was statistically inferior to the groups associated with MW for %SH, ΔKHN, and the concentration of P and Ca in the enamel (p < 0.001). Blocks treated with FT + MW 225F and FT + MW 100F-TMP showed significantly lower %SH compared to the other groups (p < 0.001). The FT + MW 100F - TMP group exhibited the lowest depth mineral loss (ΔKHN), and higher concentration de P in enamel (p < 0.001). CONCLUSION: The adjunct use of MW with FT produces a greater protective effect in inhibiting enamel demineralization, and the supplementation of TMP to the MW with 100F provides a superior effect compared to MW with 225F. CLINICAL SIGNIFICANCE: This combination of treatments could be regarded as one of several alternative fluoride supplements for subjects at elevated risk of caries.

Effectiveness of fluorides in root caries prevention, Department of Veterans Affairs (2009-2018).

AIMS: The aim of this study was to examine the effectiveness of topical fluorides in prevention of root caries-related treatment in high caries risk Veterans. METHODS: This retrospective analysis of longitudinal data examined the effectiveness of professionally applied or prescription (Rx) fluoride treatment, in VHA clinics from FY 2009-2018. Professional fluoride treatments included 5% Sodium Fluoride (NaF) varnish (22 600 ppm fluoride), 2% NaF gel/rinse (9050 ppm fluoride), and 1.23% APF gel (12 300 ppm fluoride). The Rx for daily home use was 1.1% NaF paste/gel (5000 ppm fluoride). Outcomes studied were new root caries restorations or extractions and percent of patients with treatment over 1 year. Logistic regressions were adjusted for age, gender, race, ethnicity, chronic medical or psychiatric conditions, number of medication classes, anticholinergic drugs, smoking, baseline root caries treatment, preventive care, and time between first-last restoration in the index year. RESULTS: Root caries at baseline was associated with a high risk for new root caries. Veterans without root caries during the index year who received a fluoride gel/rinse intervention were 32-40% less likely to receive caries-related treatment for root caries during the follow-up period. Once Veterans had root caries, fluorides did not exhibit a positive effect. CONCLUSION: In older adults with high caries risk, early fluoride prevention is key, before root caries requires treatment.

Screening, Referral, Behavioral Counseling, and Preventive Interventions for Oral Health in Children and Adolescents Aged 5 to 17 Years: A Systematic Review for the US Preventive Services Task Force.

Importance: Dental caries is common in children and adolescents aged 5 to 17 years and potentially amenable to primary care screening and prevention. Objective: To systematically review the evidence on primary care screening and prevention of dental caries in children and adolescents aged 5 to 17 years to inform the US Preventive Services Task Force. Data Sources: MEDLINE, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews (to October 3, 2022); surveillance through July 21, 2023. Study Selection: Diagnostic accuracy of primary care screening instruments and oral examination; randomized and nonrandomized trials of screening and preventive interventions and systematic reviews of such studies; cohort studies on primary care oral health screening and preventive intervention harms. Data Extraction and Synthesis: One investigator abstracted data; a second checked accuracy. Two investigators independently rated study quality. Random-effects meta-analysis was performed for fluoride supplements and xylitol; for other preventive interventions, pooled estimates were used from good-quality systematic reviews. Main Outcomes and Measures: Dental caries, morbidity, functional status, quality of life, harms; diagnostic test accuracy. Results: Three systematic reviews (total 20 684 participants) and 19 randomized clinical trials, 3 nonrandomized trials, and 1 observational study (total 15 026 participants) were included. No study compared screening vs no screening. When administered by dental professionals or in school settings, fluoride supplements compared with placebo or no intervention were associated with decreased change from baseline in the number of decayed, missing, or filled permanent teeth (DMFT index) or decayed or filled permanent teeth (DFT index) (mean difference, -0.73 [95% CI, -1.30 to -0.19]) at 1.5 to 3 years (6 trials; n = 1395). Fluoride gels were associated with a DMFT- or DFT-prevented fraction of 0.18 (95% CI, 0.09-0.27) at outcomes closest to 3 years (4 trials; n = 1525), fluoride varnish was associated with a DMFT- or DFT-prevented fraction of 0.44 (95% CI, 0.11-0.76) at 1 to 4.5 years (5 trials; n = 3902), and resin-based sealants were associated with decreased risk of carious first molars (odds ratio, 0.21 [95% CI, 0.16-0.28]) at 48 to 54 months (4 trials; n = 440). No trial evaluated primary care counseling or dental referral. Evidence on screening accuracy, silver diamine fluoride, xylitol, and harms was very limited, although serious harms were not reported. Conclusions and Relevance: Administration of fluoride supplements, fluoride gels, varnish, and sealants in dental or school settings improved caries outcomes. Research is needed on the effectiveness of oral health preventive interventions in primary care settings and to determine the benefits and harms of screening.

Effect of Plant-Based Mouthwash (Morinda citrifolia and Ocimum sanctum) on TNF-α, IL-α, IL-ß, IL-2, and IL-6 in Gingival Crevicular Fluid and Plaque Scores of Patients Undergoing Fixed Orthodontic Treatment.

Background and Objectives: To investigate the antiplaque properties of two plant-based mouthwashes, Morinda citrifolia (MC) and Ocimum sanctum (OS), and their effect on TNF-α, IL-α, IL-ß, IL-2, and IL-6 in gingival crevicular fluid (GCF) of patients undergoing fixed orthodontic treatment. Materials and Methods: Seventy-five individuals were recruited according to defined inclusion and exclusion criteria. This study was structured into two distinct phases. Phase I was a combination of toothbrushing using toothpaste containing fluoride (Protocol A), while Phase II toothbrushing included fluoride toothpaste and use of a mouthwash (Protocol B). For Phase II, individuals participating in this study were allocated into different groups through a randomization process: Group 1-0.12% CHX, Group 2-5% MC, and Group 3-4% OS. Each individual's Phase I and Phase II scores were assessed. GCF was measured in three phases to determine the level of inflammatory biomarkers. The paired t-test evaluated the disparities between the pre- and post-plaque index. Categorical data were subjected to crosstab analysis to assess qualitative variables. The mean values of cytokine levels were presented. An unpaired t-test was employed to assess the levels of cytokines between individuals in Phase I and Phase II. Results: Toothbrushing, fluoride toothpaste, and the supplementary use of mouthwash (Phase II) resulted in mean plaque scores significantly lower than group A (p < 0.001). Cytokines TNF-α, IL-α, and IL-ß demonstrated a significant downward trend in herbal mouthwash users. Conclusions: In conjunction with fluoridated toothpaste and brushing, OS and MC can serve as a viable alternative to conventional synthetic mouthwash CHX. This combination demonstrates reducing mean plaque scores and diminishing the levels of cytokines TNF-α, IL-α, and IL-ß.

Effects of fluoride on oxidative DNA damage, nitric oxide level, lipid peroxidation and cholinesterase enzyme activity in a rotenone-induced experimental Parkinson's model.

OBJECTIVE: Environmental toxins are known to be one of the important factors in the development of Parkinson's disease (PD). This study was designed to investigate the possible contribution of fluoride (F) exposure to oxidative stress and neurodegeneration in rats with PD induced by rotenone (ROT). MATERIALS AND METHODS: A total of 72 Wistar albino male rats were used in the experiment and 9 groups were formed with 8 animals in each group. ROT (2 mg/kg) was administered subcutaneously (sc) for 28 days. Different doses of sodium fluoride (NaF) (25, 50 and 100 ug/mL) were given orally (po) for 4 weeks. Malondialdehyde (MDA), glutathione (GSH), nitric oxide (NO), oxidative DNA damage (8-OHdG) and cholinesterase (AChE/BChE) enzyme activities were evaluated in serum and brain tissue homogenates. RESULTS: Rats treated with ROT and NaF had significant increases in serum and brain MDA, NO content, and decreases in GSH. In addition, the combination of ROT and NaF triggered oxidative DNA damage and resulted in increased AChE/BChE activity. CONCLUSIONS: Findings suggest that NaF and ROT may interact synergistically leading to oxidative damage and neuronal cell loss. As a result, we believe that exposure to pesticides in combination with NaF is one of the environmental factors that should not be ignored in the etiology of neurological diseases such as PD in populations in areas with endemic fluorosis.

Effect of three different remineralising agents on prevention against acidic erosion of primary teeth: an in vitro study.

PURPOSE: This study aimed to evaluate and compare the protective effect of fluoride varnish (Enamelast™, Ultradent Inc., Cologne, Germany), casein phosphopeptide-amorphous calcium phosphate fluoride/CPP-ACPF (MI Paste Plus, GC Corp., Tokyo, Japan) and self-assembling P11-4 peptide (Curodont™ Protect, Credentis AG, Windisch, Switzerland), against acidic erosion of primary teeth. METHODS: Forty primary anterior teeth were randomly assigned to four groups (n = 10): group 1: control, group 2: fluoride varnish, group 3: CPP-ACPF and group 4: self-assembling P11-4 peptide. After applying remineralising agents, except for the control group, all specimens underwent an erosive challenge of carbonated soft drink and artificial saliva for 15 cycles of 6 s each at 6-h intervals for a day. Groups were compared in terms of surface microhardness, roughness readings, and surface scanning with an extra-oral scanner (D800; 3Shape A/S) before and after the erosive process. RESULTS: All experimental groups showed superior results than the control group regarding microhardness, surface roughness, and substance loss. The fluoride varnish group showed significantly favourable results in microhardness change. There was no significant difference between the experimental groups regarding surface roughness and enamel loss measurements. CONCLUSION: 5% NaF fluoride varnish, CPP-ACPF and self-assembling P11-4 peptide protect the enamel of primary teeth against erosion compared to artificial saliva alone.

Remineralization Potential of a Novel Biomimetic Material (Self-assembling Peptide P11-4) on Early Enamel Caries: An In Vitro Study.

AIM: To assess the remineralizing potential of self-assembling peptide P11-4 and compare it to the remineralizing potential of fluoride varnish using DIAGNOdentTM, as well as the amount of mineral gain after application of fluoride varnish and self-assembling peptide P11-4. MATERIALS AND METHODS: This study included 20 premolars extracted during orthodontic therapy with all surfaces intact and free of hypoplastic regions, white spot lesions (WSL) and dental caries. The teeth sample for Curodont RepairTM (self-assembling P11-4) and Bifluorid 10® (fluoride varnish) was equally divided. On each tooth surface, a 2 × 2 mm window was created. The samples were immersed in a demineralizing solution for 96 hours before being subjected to DIAGNOdentTM pen reading, ICDAS-II scoring, and scanning electron microscopy-energy-dispersive X-ray (SEM-EDX) analysis on one half of the sample. The remineralizing agents were applied to the second half of the sample according to the manufacturer's instructions and placed in artificial saliva for 21 days, with the artificial salvia being replaced every 24 hours. After 21 days, the second half of the sample was subjected to DIAGNOdentTM pen reading, ICDAS-II score, and SEM-EDX analysis. RESULTS: Following remineralization, the DIAGNOdentTM pen and ICDAS-II score values differed statistically between the two groups, with the Bifluorid 10® group reporting higher mean values (p > 0.05) using t-test analysis. Energy-dispersive X-ray analysis using the t-test revealed a statistically significant result for remineralization (p < 0.05), with CurodontTM Repair group (55.150.84) reporting better mean values than Bifluorid 10® for phosphorus and calcium, but Bifluorid 10® reporting a higher result in remineralization (p < 0.05) than CurodontTM Repair for fluoride. CONCLUSION: CurodontTM Repair showed better remineralizing potential compared with Bifluorid 10® varnish. In terms of the mineral gain, CurodontTM Repair showed better results for calcium and phosphorus post-remineralization. Whereas Bifluorid 10® showed a higher gain in terms of fluoride. Self-assembling peptide P11-4 can be used as an alternative to fluoride varnish for remineralizing WSL. CLINICAL SIGNIFICANCE: Self-assembling polypeptide P11-4 is a novel remineralizing agent for initial enamel lesions, which is the least-invasive method of enamel remineralization.

Oral care and the use of fluoride in the prevention of radiation-related caries: A scoping review.

OBJECTIVE: This scoping review aimed to map the literature on oral hygiene protocols and fluoride use in patients undergoing radiotherapy. STUDY DESIGN: A comprehensive search was performed in 10 databases, including part of the "gray literature." Clinical trials and observational studies that used radiotherapy in the head and neck region and evaluated the occurrence of radiation-related caries (RRC) were included. RESULTS: Twenty-one studies were included in the review. The studies generally presented different methods of oral care and fluoride use. Several studies have shown promising results for oral care instructions in preventing RRC. The main strategies found in the articles were oral hygiene instructions, professional teeth cleaning, recommendations for the use of fluoride toothpaste, and monthly follow-ups. Fluoride gel was the most commonly used fluoride product (72%). Its main recommendation for use was at least 5 min at night daily. Most of these studies (60%) used custom-made trays. Other fluoride methods were fluoride varnish, mouthrinses, and high-fluoride-containing toothpaste. CONCLUSION: Oral care, such as hygiene instructions with regular dental follow-up and daily fluoride, seem to be promising strategies for preventing RRC. Periodically monitoring these patients is one of the most important strategies.

Effect of self-assembling peptide and other remineralizing agents on preventing initial enamel lesions around orthodontic brackets: An in vitro comparative study.

OBJECTIVE: To investigate and compare the effect of self-assembling peptide SAP (P11-4), casein phosphopeptide-amorphous calcium phosphate fluoride paste (CPP-ACPF), and fluoride varnish (FV) on preventing enamel demineralization around orthodontic brackets. MATERIAL AND METHODS: Orthodontic brackets were bonded to the buccal surfaces of 80 freshly extracted human maxillary premolars. Teeth were randomly assigned to four groups (n=20) according to the remineralizing agent used as follows: SAP (P11-4) group (Curodont™ Protect/Credentis), CPP-ACPF group (MI Paste Plus®/Recaldent™), fluoride varnish group (Profluoride varnish®/VOCO), and control group. All products were applied according to the manufacturer's instructions. Specimens were cycled in daily refreshed demineralizing and remineralizing solutions for 8h and 16h, respectively, for 28 days. The calcium/phosphorus ratio (Ca/P) and surface microhardness (SMH) were evaluated at baseline and at two and four weeks. Two-way ANOVA (analysis of variance), one-way ANOVA and repeated measures ANOVA were used for statistical analysis. RESULTS: Two-way ANOVA demonstrated significant differences between remineralizing agents and time points. After 4 weeks, the SAP (P11-4) group had had significantly higher Ca/P ratio and SMH (1.68±0.11 and 346.47±55.38) compared to other groups, followed by CPP-ACPF (1.52±0.19 and 283.53±64.75), FV (1.37±0.14 and 262.80±82.98), and the control group (1.31±0.10 and 213.00±41.95). Significantly higher Ca/P ratio and SMH were observed at 2 weeks in the control group (1.44±0.10 and 269.63±57.37) and FV group (1.52±0.09 and 321.17±55.24) compared to 4 weeks. No significant differences were found regarding Ca/P ratio and SMH at 2 weeks in the CPP-ACPF (1.55±0.15 and 295.14±53.88) and SAP P11-4 groups (1.64±0.10 and 320.18±58.04) compared to 4 weeks. CONCLUSION: SAP (P11-4) had the greatest remineralizing efficacy compared to FV and CPP-ACPF. Moreover, extended period of time improved the preventive efficacy of SAP (P11-4) compared to the other regimens.

Dental Caries Postradiotherapy in Head and Neck Cancer.

BACKGROUND: Treatment for head and neck cancer (HNC) such as radiotherapy (RT) can lead to numerous acute and chronic head and neck sequelae, including dental caries. The goal of the present study was to measure 2-y changes in dental caries after radiotherapy in patients with HNC and test risk factors for caries increment. METHODS: Cancer and dental disease characteristics, demographics, and oral health practices were documented before and 6, 12, 18, and 24 mo after the start of RT for 572 adult patients with HNC. Patients were eligible if they were age 18 y or older, diagnosed with HNC, and planned to receive RT for treatment of HNC. Caries prevalence was measured as decayed, missing, and filled surfaces (DMFS). The association between change in DMFS and risk factors was evaluated using linear mixed models. RESULTS: On average, DMFS increased from baseline to each follow-up visit: 6 mo, +1.11; 12 mo, +2.47; 18 mo, +3.43; and 24 mo, +4.29 (P < 0.0001). The increase in DMFS during follow-up was significantly smaller for the following patient characteristics: compliant with daily fluoride use (P = 0.0004) and daily oral hygiene (brushing twice daily and flossing daily; P = 0.015), dental insurance (P = 0.004), and greater than high school education (P = 0.001). DMFS change was not significantly associated with average or maximum RT dose to the parotids (P > 0.6) or salivary flow (P > 0.1). In the subset of patients who had salivary hypofunction at baseline (n = 164), lower salivary flow at follow-up visits was associated with increased DMFS. CONCLUSION: Increased caries is a complication soon after RT in HNC. Fluoride, oral hygiene, dental insurance, and education level had the strongest association with caries increment after radiotherapy to the head and neck region. Thus, intensive oral hygiene measures, including fluoride and greater accessibility of dental care, may contribute to reducing the caries burden after RT in HNC. KNOWLEDGE TRANSFER STATEMENT: The results of this study can be used by clinicians when deciding how to minimize oral complications related to cancer therapy for patients with head and neck cancer. Identification of modifiable factors (e.g., oral hygiene and prescription fluoride compliance) associated with increased caries risk can minimize radiation caries burden.

Evaluation of three different remineralizing agents on artificially demineralized enamel lesions: Using scanning electron microscopy-energy dispersive X-ray and magic-angle spinning nuclear magnetic resonance - An in vitro study.

Aim: Demineralization can be arrested or reversed when remineralization agents are applied to incipient carious or noncavitated carious lesions. A large number of therapeutic agents, including nonfluoridated products, have been developed to promote enamel remineralization. This study aims to evaluate the efficacy of different remineralizing agents on artificially demineralized enamel lesions. Materials and Methods: The present in vitro study was conducted on 75 sound premolars divided into three groups of normal, demineralized (n = 15 each), and remineralized teeth (n = 45). The remineralized teeth were further subdivided into three groups (n = 15) as remineralized with 2% sodium fluoride (NaF), 2% NaF, and Psoralea corylifolia (bakuchi) and white mineral trioxide aggregate. Specimens of each group were treated with the above-mentioned remineralizing agents and then subjected to Vickers hardness number (VHN), scanning electron microscopy-energy dispersive X-ray (SEM-EDX), and magic-angle spinning nuclear magnetic resonance (MAS-NMR) for further evaluation. Results: The test results showed significantly the highest VHN and the emission peak of elements under the EDX test, such as calcium, phosphorous, oxygen, and fluorine with remineralized with NaF + bakuchi. MAS-NMR spectra showed fluorine and phosphorous peak in a group with NaF + bakuchi indicative of the increase in remineralization. NaF + bakuchi showed effective results in VHN, SEM-EDX, and MAS-NMR with no antagonist interaction. Conclusion: Thus, P. Corylifolia presents an advantage in enhancing remineralization and inhibiting demineralization for early carious lesions and can be used as a herbal extract for effective reduction in pathogenic bacteria.

Potencial remineralizante del fluoruro diamino de plata al 38% en dentina de dientes temporales afectada por caries / Remineralizing potential of 38% silver diamine fluoride in dentin affected by dental caries

Introducción: la caries es una enfermedad compleja que afecta a cualquier edad. La prevalencia es mayor en la primera dentición, sobre todo en población con baja percepción económica. El fluoruro diamino de plata (FDP) al 38% ha sido utilizado como una alter- nativa de tratamiento para esta enfermedad. Funciona como una solución remineralizante y cariostática. Objetivo: evaluar el efecto remineralizante del FDP al 38% en dentina afectada por lesiones de caries en molares temporales. Material y métodos: estudio clínico, epidemiológico, descriptivo, longitudinal y experimental. Se llevó a cabo en molares de primera dentición de niños de tres a cinco años de edad. Los niños seleccionados tenían molares con lesiones cariosas dentinarias, Pitts las denomina D3. No se incluyeron niños con dientes que presentaron patologías pulpares irreversibles. La aplicación del FDP al 38% la efectuó un operador entrenado para esta finalidad. Se utilizaron los criterios de Nyvad para determinar el grado de dureza de la dentina y con ello deducir su remineraliza- ción. Se observó la permanencia de la remineralización efectuada por un periodo de cinco meses. Resultado y conclusión: el FDP es un compuesto eficaz en 91% de los casos en un periodo de cinco meses o más (AU)

Introduction: dental caries is a complex disease that affects any age. The prevalence is higher in primary dentition, especially in a population with low economic perception. 38% silver diamine fluoride (FDP) has been used as an alternative treatment for this disease. It works as a remineralizing and cariostatic solution. Objective: to evaluate the remineralizing effect of 38% FDP on dentin affected by dental caries, in temporary molars. Material and methods: clinical, epidemiological, descriptive, longitudinal and experimental study. It was carried out in temporary molars of children between three and five years of age. The selected children presented molars with dental carious lesions, Pitts calls them D3. Children with teeth that presented irreversible pulp pathologies were not included. The application of the FDP to 38% was carried out by an operator trained for this purpose. The Nyvad criteria were used to determine the degree of hardness of the dentin and thereby deduce its remineralization. The permanence of the remineralization carried out was observed for a period of five months. Result and conclusion: the FDP is an effective compound in 91% of the cases, in a period of five months or more (AU)

Color stability and microhardness alteration of irradiated dental enamel treated with a high fluoride concentration toothpaste.

OBJECTIVES: Radiotherapy (RT) is a kind of head and neck cancer (HNC) treatment, which is associated to the habit of smoking and can develop collateral effects in the oral cavity, such as the increase of caries prevalence. This study evaluated the color alteration, the microhardness, and the remineralizing potential of high fluoride concentration toothpastes on irradiated teeth. MATERIALS AND METHODS: Forty bovine teeth were used (6 × 6 × 2 mm) and after color (EasyShade, VITA) and microhardness initial readings were separated into two groups: exposed to cigarette smoke and non-exposed. All samples were submitted to RT (30 Gy) and to cariogenic challenge. New color and microhardness readings were done. After RT (60 Gy), the samples were submitted to simulated toothbrushing (73,000 cycles = 5 years of brushing) with two different toothpastes: conventional (1450 ppm) and high fluoride concentration (5000 ppm). Final color and microhardness readings were done after brushing. Data were analyzed with 2-way ANOVA with repeated measures and Tukey's test (p < .05). RESULTS: There was no color difference after RT, nor after brushing (p > .05). However, after brushing, microhardness values increased for the samples treated with high fluoride concentration toothpaste (p < .05). CONCLUSION: Radiotherapy did not influence the teeth color, and the high fluoride concentration toothpaste presented remineralizing potential; therefore, it could be used on the caries prevention related to HNC radiation. CLINICAL RELEVANCE: Considering its remineralizing potential, toothpastes with high fluoride concentration could be a proper alternative for caries prevention in patients undergoing radiotherapy.

Effectiveness of topical fluorides in prevention of radiation caries in adults: A systematic review and meta- analysis.

BACKGROUND: Topical fluoride is used for prevention of dental caries. However, its effectiveness and more specifically its formulation and frequency of application in patients undergoing head and neck radiotherapy are still debatable. The aim of this systematic review was to pool the evidence of effectiveness of various topical fluorides in preventing radiation caries or change in bacterial growth in adult patients of head and neck cancer. METHODS: Three databases (PubMed and Google Scholar and Cochrane) were searched for randomized controlled or uncontrolled trials or quasi randomised trials published till February 2021. Two independent reviewers screened 346 abstracts finally 14 articles were included in the current systematic review. Primary outcome evaluated was the prevention of radiation caries or change in bacterial growth in saliva. Meta-analysis was performed for the sub groups formed on the basis of fluoride formulations and adjuncts used with it. RESULTS: Studies included were highly heterogeneous. Majority of studies found different fluoride formulations to be effective in controlling radiation caries to a variable extent up to 70% depending upon the intervention, patient compliance, rate of attrition and follow up period. Sodium fluoride was the most commonly used caries preventive agent. Meta-analysis showed no significant difference between sodium fluoride formulations and other fluoride agents. Fluoride treatment when incorporated with re-mineralising agent had no significant effect on caries prevention CONCLUSION: Fluoride prevents radiation caries. However, to delineate its exact formulation, dosage or frequency, there is need for more well conducted randomised controlled trials.

Debonding of orthodontic appliance changes salivary physicochemical properties and favors regression of active caries lesions: A 13-week follow-up study.

AIM: This prospective cohort study aimed to investigate whether orthodontic appliance removal (OAR) combined with caries-preventive strategies and fluoride varnish treatments alters salivary physicochemical properties, changes the activity of carbonic anhydrase VI (CA VIACT ) and α-amylase (α-AMLACT ), and favors the regression of active caries lesions (ACL). DESIGN: Twenty-two individuals aged between 13 and 24 years were assessed for the presence of visible biofilm, daily sugar exposure, caries activity, salivary flow rate (SFR), pH, buffering capacity (BC), and CA VIACT and α-AMLACT activity at baseline, and 1, 5, and 13 weeks after OAR. Variables were assessed using repeated-measures analysis of variance, Cochran's Q and McNemar's test, and Pearson's correlation. RESULTS: We observed a significant decrease in the number of ACL at the 5-week (29% reduction) and 13-week follow-ups (58% reduction). At the 5- and 13-week follow-ups, the percentage of visible biofilm and sugar exposure decreased, whereas the salivary pH and α-AMLACT activity significantly increased. BC and CA VIACT remained unchanged throughout the follow-up. CONCLUSION: OAR combined with caries-preventive strategies and fluoride varnish treatments favored the regression of ACL and increased salivary pH and α-AMLACT activity, whereas BC and CA VIACT remained stable.

Dual-Responsive and ROS-Augmented Nanoplatform for Chemo/Photodynamic/Chemodynamic Combination Therapy of Triple Negative Breast Cancer.

Integrating chemodynamic therapy (CDT) and photodynamic therapy (PDT) into one nanoplatform can produce much more reactive oxygen species (ROS) for tumor therapy. Nevertheless, it is still a great challenge to selectively generate sufficient ROS in tumor regions. Meanwhile, CDT and PDT are restricted by insufficient H2O2 content in the tumor as well as by the limited tumor tissue penetration of the light source. In this study, a smart pH/ROS-responsive nanoplatform, Fe2+@UCM-BBD, is rationally designed for tumor combination therapy. The acidic microenvironment can induce the pH-responsive release of doxorubicin (DOX), which can induce tumor apoptosis through DNA damage. Beyond that, DOX can promote the production of H2O2, providing sufficient materials for CDT. Of note, upconversion nanoparticles at the core can convert the 980 nm light to red and green light, which are used to activate Ce6 to produce singlet oxygen (1O2) and achieve upconversion luminescence imaging, respectively. Then, the ROS-responsive linker bis-(alkylthio)alkene is cleaved by 1O2, resulting in the release of Fenton reagent (Fe2+) to realize CDT. Taken together, Fe2+@UCM-BBD exhibits on-demand therapeutic reagent release capability, excellent biocompatibility, and remarkable tumor inhibition ability via synergistic chemo/photodynamic/chemodynamic combination therapy.

Research Trends on Preventive and Therapeutic Use of TIF4 for Dental Caries and Erosion

Abstract Objective: To evaluate TIF4 preventive and therapeutic use in caries and erosive lesions. Material and Methods: Searches were performed in six databases. Studies evaluating TiF4 use in vitro, in situ, and in vivo in caries and erosive lesions were included and imported into VantagePoint™ (VP). Data about publication year, authors, country, journal, study design, outcomes, TIF4 vehicles, application and intervention time, cariogenic challenge, erosive cycles, effects (positive/ negative /null) and approach (preventive/therapeutic) were analyzed through VP and Excel. Results: 93 published studies were included and an increase in publications was observed between 2010 and 2021. Forty-three authors published three or more articles, of which 67.4% were developed in Brazil and published in Caries Research (22.6%). 69.9% were in vitro studies with erosion assays (59.1%) and with preventive approaches (67.4%). The principal vehicle was a solution (69.9%) with a 1-min single application (58.0%) and with an intervention time of 5-7 days (22.6%). The principal cariogenic challenge in vitro was pH cycling (11.8%); in situ was sucrose + biofilm (6.2%); and in vivo, biofilm (6.2%). The most used erosive cycle was 4× per day in in vitro studies (20.4%) and 1× in vivo (2.1%). A positive effect was observed in prevention (41.9%) and treatment (24.7%) studies. Conclusion: TIF4 has shown a positive effect in prevention and therapeutic treatments for dental caries and erosion (AU).

A Janus upconverting nanoplatform with biodegradability for glutathione depletion, near-infrared light induced photodynamic therapy and accelerated excretion.

The major limitations of photodynamic therapy (PDT) are the poor tissue penetration of excitation light and the neutralization of reactive oxygen species (ROS) generated by overexpressed glutathione (GSH) in cancer cells. Despite tremendous efforts to design nanoplatforms, PDT still suffers from unsatisfactory effects. Furthermore, the residual of nanomaterials in the body has restricted their clinical application. To address these issues, Janus nanocomposites containing an Yb/Er codoped NaYF4 upconverting nanocrystal head and a disulfide-bridged mesoporous organosilicon body (UCN/MON) with loaded chlorin e6 (Ce6) were designed. On one hand, the upconverting nanocrystal head can convert near-infrared (NIR) light into visible light to activate Ce6 to release ROS. On the other hand, the silica body can be degraded though a redox reaction with GSH, to not only improve the tumor selectivity of the photosensitizer by redox- and pH-triggered Ce6 release, but also diminish the concentration of GSH in cancer cells to reduce the depletion of ROS. Thereby, an enhanced PDT triggered by NIR irradiation was achieved. Furthermore, UCN/MONs showed a higher clearance rate after therapeutic actions than nonbiodegradable UCN/MSNs due to their biocompatibility. Taken together, this work revealed the potential of UCN/MONs for highly efficient and NIR-induced PDT, highlighting the prospects of UCN/MONs in the clinic.

An NIR-II/MR dual modal nanoprobe for liver cancer imaging.

Hepatocellular carcinoma (HCC) is a malignancy of the liver worldwide and surgical resection remains the most effective treatment. However, it is still a great challenge to locate small lesions and define the border of diffused HCC even with the help of preoperative imaging examination. Here, we reported a rare-earth-doped nanoparticle NaGdF4:Nd 5%@NaGdF4@Lips (named Gd-REs@Lips), which simultaneously performed powerful functions in both magnetic resonance imaging (MRI) and second near-infrared fluorescence window imaging (NIR-II, 1000-1700 nm). Imaging studies on orthotopic models with xenografts established from HCC patients indicated that Gd-REs@Lips efficiently worked as a T2-weighted imaging contrast agent to increase the signal intensity difference between liver cancer tissues and surrounding normal liver tissues on MRI, and it can also serve as a negative NIR-II imaging contrast enabling the precise detection of liver cancer. More importantly, benefiting from the high sensitivity of NIR-II imaging, Gd-REs@Lips allowed the visualization of tiny metastasis lesions (2 mm) on the liver surface. It is expected that the dual NIR-II/MRI modal nanoprobe developed holds high potential to fill the gap between the preoperative imaging detection of cancer lesions and intra-operative guidance, and it further brings new opportunities to address HCC-related medical challenges.