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Purpose: This randomized in vitro study determined parameters for using a light-emitting diode (LED) with toluidine blue O (TBO) for reduction of Streptococcus mutans counts inside carious dentin. Materials and Methods: Seventy-two bovine coronary dentin slabs were immersed in Streptococcus mutans culture for demineralization. Dentin slabs were allocated to 6 groups (n = 12) as follows: control (treated with 0.9% NaCl solution for 5 min); TBO (treated with 0.1 mg/ml TBO for 5 min); LEDA (submitted to irradiation for 4.2 min); LEDB (submitted to irradiation for 6.5 min); photodynamic therapy A (PDTA; treated with TBO plus irradiation for 4.2 min) and photodynamic therapy B (PDTB; treated with TBO plus irradiation for 6.5 min). The energy densities used for 4.2 and 6.5 min correspond to 166 and 249 J/cm2, respectively. Before and after treatments, dentin samples were analyzed with regard to S. mutans counts. The carious lesion depth produced by the microbiological model was analyzed by polarized light microscopy. ANOVA/Tukey tests were utilized to compare log reductions among groups (alpha = 5%). Results: Bacterial reduction was observed when dentin was exposed to both TBO and LED at both irradiation times. However, no difference in S. mutans reduction was found between the two energy densities. Conclusion: Although the use of LED combined with TBO was effective in reducing the Streptococcus mutans counts in carious dentin, this effect may not have clinical significance. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the present study was to undertake a systematic review to investigate whether mutans streptococci levels are a strong risk indicator/factor for ECC, based on the current quality of the literature regarding the relationship between early childhood caries (ECC) and these microorganisms.Materials and Methods: The authors searched PubMed, Scopus and Cochrane Library databases for papers from 1951 to 2007. The minimal inclusion requirements were assessment of preschool children reporting mutans streptococci counts, mainly in saliva and biofilm samples, and caries assessment. Since the heterogeneity of the studies did not allow a meta-analysis (chi(2) test), a qualitative analysis was conducted.Results: The electronic search yielded 120 articles, but only 16 scientific papers were critically appraised. Of the 16 scientific papers included in the review, only one cross-sectional study achieved a high value of evidence.Conclusions: It was concluded that mutans streptococci levels are a strong risk indicator for ECC. However, further well designed longitudinal studies with high evidence values are required to confirm mutans streptococci levels as a significant ECC risk factor. [ABSTRACT FROM AUTHOR]

Karina Ferreira Rizzardi, 1 Lidiany Karla Azevedo Rodrigues, 2 Carolina Steiner-Oliveira, 3 Marines Nobre-dos-Santos, 3 Thaís Manzano Parisotto 1 1Laboratory of Molecular and Clinical Microbiology, University São Francisco, Bragança Paulista, SP, Brazil; 2Faculty of Pharmacy, Dentistry and Nursing, Federal University of Ceará, Fortaleza, CE, Brazil; 3Piracicaba Dental School, University of Campinas, Piracicaba, SP, BrazilCorrespondence: Thaís Manzano ParisottoLaboratory of Molecular and Clinical Microbiology, University São Francisco, Av. São Francisco de Assis, 218, Bragança Paulista, SP 12916-900, BrazilTel +55 11 24548474Email thaisparisotto@gmail.comObjective: This longitudinal study aimed to investigate if the plaque fluoride (PF) concentration can predict the early childhood caries onset. Design: As part of a larger study, 188 preschoolers were clinically evaluated for early childhood caries diagnosis, at baseline and after 1-year follow-up. After that, the final sample comprised: 1. children who had already caries at baseline (decayed, missing or filled surfaces, as well as white chalky white spot lesions adjacent to gingival margins) and developed at least one more cavitation after one year (n=16), and 2. children who never had or developed any caries lesions, including active white spots lesions (n=15). Before the clinical examinations, dental plaque was collected. PF concentration was determined with an ion-specific electrode. A chart was used to estimate the mean daily sugar exposure. The results were statistically analyzed by Spearman correlation and logistic regression analyses (α=0.05).Results: After one year, a positive significant correlation between caries development and liquid sucrose, total sugar and total sucrose consumption increments was found (p< 0.05). Moreover, the solid sugar, solid sucrose and total sugar exposure at baseline were positively correlated with the presence of dental plaque at follow-up (p< 0.05). To top it all, children with PF concentrations ≤ 0.1 μg/mg at baseline were 10 times more likely to develop caries.Conclusion: In conclusion, this study demonstrated for the first time in vivo that low PF concentration is a predictor of caries development in primary teeth.Keywords: dental caries, preschool child, fluoride, biofilm

Background: Semaglutide has emerged as an effective medication for treating type 2 diabetes mellitus (DM). However, the cardiovascular effects and safety of this agent in patients with heart failure with preserved ejection fraction (HFpEF) are unclear., Objective: This systematic review and meta-analysis aimed to assess the clinical and laboratory effects of semaglutide compared to placebo in patients with HFpEF., Methods: We systematically searched EMBASE, PubMed, and Cochrane databases for randomized controlled trials (RCTs) and non-randomized cohorts, from inception to July 2024, comparing semaglutide versus placebo in patients with HFpEF. Statistical analyses were performed using R Studio 4.3.2. Mean difference (MD) and odds ratio (OR) with 95% confidence intervals (CIs) were pooled across trials., Results: This meta-analysis included three studies, two RCTs and one non-randomized cohort, reporting data on 1463 patients. The follow-up time of the studies was 52 weeks. Compared to placebo, the use of semaglutide was associated with a significant increase in the 6-min walk distance (MD 16.20; 95% CI 10.19-22.21; p < 0.01; I 2  = 0%). Additionally, reductions were observed in systolic blood pressure (MD -2.22; 95% CI -3.60 to -0.83; p < 0.01; I 2  = 0%), C-reactive protein level (MD 0.59; 95% CI 0.49-0.70; p < 0.01; I 2  = 51%), and N-terminal prohormone of brain natriuretic peptide (NT-proBNP) levels (MD 0.81; 95% CI 0.74-0.89; p < 0.01; I 2  = 0%)., Conclusion: These findings suggest that the use of semaglutide is associated with clinical and laboratory benefits in patients with HFpEF., Competing Interests: Declarations. Funding: None. Conflict of interest: All authors report no relationships that could be construed as a conflict of interest. All authors take responsibility for all aspects of the reliability and freedom from bias of the data presented and their discussed interpretation. Ethics approval: Not applicable. Consent to participate: Not applicable. Consent for publication: Not applicable. Availability of data and materials: As this is a systematic review with meta-analysis, there is no database; for data extracted from other articles, see Table 1. Code availability: Not applicable. Author contributions: MS carried out the idealization of the work as well as the screening, risk-of-bias assessments, writing of the article, and coordination and supervision of the work. LR, carried out the idealization of the work as well the risk-of-bias assessments and writing the article. AB carried out the collection of outcomes and was involved in writing the article. NR carried out the collection of outcomes and was involved in writing the article. IM took part in writing the article. JS produced Table 1 and wrote the article. BO carried out the screening and was involved in writing the article. JM took part in writing the article. FP was involved in the supervision and coordination of the research group. CG participated in the writing of the article and supervision and coordination of the research group., (© 2025. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Objective: To evaluate the efficacy and safety of elinzanetant compared to placebo in patients experiencing vasomotor symptoms (VMS) associated with menopause., Methods: A systematic search of PubMed, Embase, and Cochrane databases identified randomized clinical trials (RCTs) comparing elinzanetant and placebo in patients with menopause-related VMS. Statistical analyses pooled mean difference (MD) and risk ratio (RR) with 95% confidence intervals (CI) using R Studio 4.3.2. Pre-specified outcomes included frequency and intensity of VMS, quality of life, and sleep disturbance., Results: This meta-analysis included three randomized clinical trials reporting data on 995 patients, with 551 receiving elinzanetant. The mean age ranged from 54.4 to 55.6 years. Elinzanetant significantly reduced VMS frequency (MD -3.09; 95 % CI -4.18 to -2.01; I 2  = 0 %) and intensity (MD -0.32; 95 % CI -0.43 to -0.21; I 2  = 39 %). Improvements in quality of life were demonstrated by reduced scores on the Menopause-Specific Quality of Life Questionnaire (MD -0.46; 95 % CI -0.63 to -0.30; I 2  = 35 %) and better sleep quality measured by the Patient-Reported Outcomes Measurement Information System Sleep Disturbance - Short Form 8b (MD -4.65; 95 % CI -5.56 to -3.73; I 2  = 0 %). The incidence of adverse events was similar between groups (RR 1.11; 95 % CI 0.99 to 1.25; I 2  = 35 %)., Conclusion: Elinzanetant reduces the frequency and intensity of VMS and enhances quality of life and sleep quality in patients with menopause-related symptoms. Its safety profile is comparable to placebo., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)

Introduction: Recent studies have demonstrated an association between hypoglycemic medications and neuroprotective action in neurodegenerative diseases, such as Parkinson's disease (PD). Therefore, in this meta-analysis, our objective was to evaluate the efficacy of these medications, compared to placebo, as disease-modifying therapy in patients with PD., Methods: We systematically searched PubMed, Embase, and Cochrane for studies comparing the use of hypoglycemic drugs and placebo in patients with PD. Statistical analyses were performed using R Studio 4.3.2. Mean difference (MD) with 95 % confidence intervals (CI) were pooled across trials. Outcomes of interest were change in Movement Disorders Society - Unified Parkinson's Disease Rating Scale (MDS-UPDRS) parts I, II, III, IV, and Parkinson's Disease Questionnaire 39 (PDQ-39)., Results: This meta-analysis included six randomized controlled trials (RCT) reporting data on 787 patients. Among them, 480 (61 %) received hypoglycemic drugs. Follow-up ranged from 36 to 61 weeks. At the end of follow-up, improvement in MDS-UPDRS part III score during OFF state occurred when subjects received any hypoglycemic agents at their lowest dose (MD -1.36; 95 % IC -2.78 to -0.47; I2 = 38 %), as well as highest doses (MD -1.58; 95 % IC -3.07 to -0.09; I2 = 50 %). Changes in MDS-UPDRS part III score in patients examined in the ON state who received any dose of any hypoglycemic agents (MD -3.32; 95 % IC -5.28 to -1.36; I2 = 0 %) were significant. There was no significant difference between groups MDS-UPDRS parts I, II, IV, and PDQ-39., Conclusion: In patients with PD, the use of hypoglycemic agents showed efficacy on symptomatic PD treatment with an improvement in MDS-UPDRS part III., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The benefits and potential risks of oral minoxidil therapy versus topical minoxidil therapy in patients with androgenetic alopecia (AGA) are controversial. We systematically searched PubMed, Embase, and Cochrane for randomized clinical trials (RCTs) comparing the use of oral minoxidil and minoxidil topical solution in patients with AGA. Statistical analyses were performed using R Studio 4.3.2. Standard mean difference (SMD) and risk ratio (RR) with 95% confidence intervals (CI) were pooled across trials. This meta-analysis included four RCTs reporting data on 279 patients. Follow-up ranged from 24 to 39 weeks. There were no differences in hair density (SMD 0.02; 95% CI -0.25 to 0.29; P = 0.88; I 2  = 0%) or hair diameter (SMD -0.25; 95% CI -0.75 to 0.26; P = 0.34; I 2  = 36%). The incidence of hypertrichosis was statistically significantly higher in the oral minoxidil group when compared to the topical minoxidil group (RR 2.01; 95% CI 1.18-3.41; P = 0.01; I 2  = 0%). There was no statistically significant difference between groups for the incidence of hypotension (RR 2.42; 95% CI 0.26-22.46; P = 0.44; I 2  = 0%). In patients with AGA, oral minoxidil and minoxidil topical solution have similar efficacy and safety, with equivalent improvements in hair density, hair diameter, and incidence of adverse events, such as hypotension., (© 2024 the International Society of Dermatology.)

Morphological, biological, serological, and molecular tests underpin the description of costus stripe mosaic virus (CoSMV) as a new member of the genus Potyvirus, family Potyviridae. Found affecting the native ornamental Costus spiralis in Brazil, the pathogen showed a severely restricted natural and experimental host range. Excluding the poly(A) tail, the CoSMV genome contains a large open reading frame (ORF) of 9,446 nucleotides that encodes a polyprotein with 3,046 amino acids, which is potentially cleaved into ten products, and a small ORF (77 amino acids) knows as PIPO. Genome analysis demonstrated the highest CoSMV nucleotide sequence identity to onion yellow dwarf virus (51.79%). No evidence of recombination was detected in the CoSMV genome, and phylogenetic analysis revealed its basal position in a group formed by members of the genus Potyvirus, along with Cyrtanthus elatus virus A (Vallota speciosa virus) and canna yellow streak virus. CoSMV was not transmitted by aphids of the species Aphis solanella, Myzus persicae or Uroleucon sonchi, which could be due to mutations in the HC-Pro motifs required for aphid transmission. A divergence in the P1 protein cleavage site was found when compared to other members of the family Potyviridae. Based on its unique biological and molecular characteristics and the current species demarcation criteria, we propose CoSMV to be a new tentative member of the genus Potyvirus.

Groin hernias are among the oldest recorded afflictions of mankind. Most of them protrude through the inguinal canal, and only a few through the femoral canal. Usually, they are present as a painful lump in the groin region, and their complications arise if they become incarcerated or strangulated. Incarcerated hernias may contain a variety of contents, such as the omentum, small bowel, colon, bladder, appendix, stomach, or ovary as previously described. Usually, the history and a physical examination are sufficient to make the diagnosis. However, the wide use of CT has become an effective instrument to identify the contents of hernias and has helped surgeons program the best management. This article reports, for the first time, the case of an 81-year-old female with an incarcerated femoral hernia that contains the gallbladder.

Objective: Materials for pulp protection should have therapeutic properties in order to stimulate remineralization and pulp reparative processes. The aim of this study was to evaluate the mechanical properties, biocompatibility, cell differentiation and bioactivity of experimental light-curable resin-based materials containing bioactive micro-fillers., Methods: Four calcium-phosphosilicate micro-fillers were prepared and incorporated into a resin blend: 1) Bioglass 45S5 (BAG); 2) zinc-doped bioglass (BAG-Zn); 3) βTCP-modified calcium silicate (β-CS); 4) zinc-doped β-CS (β-CS-Zn). These experimental resins were tested for flexural strength (FS) and fracture toughness (FT) after 24h and 30-day storage in simulated body fluid (SBF). Cytotoxicity was evaluated using MTT assay, while bioactivity was evaluated using mineralization and gene expression assays (Runx-2 & ALP)., Results: The lowest FS and FT at 24h was attained with β-CS resin, while all the other tested materials exhibited a decrease in FS after prolonged storage in SBF. β-CS-Zn maintained a stable FT after 30-day SBF aging. Incorporation of bioactive micro-fillers had no negative effect on the biocompatibility of the experimental materials tested in this study. The inclusion of zinc-doped fillers significantly increased the cellular remineralization potential and expression of the osteogenic genes Runx2 and ALP (p<0.05)., Significance: The innovative materials tested in this study, in particular those containing β-CS-Zn and BAG-Zn may promote cell differentiation and mineralization. Thus, these materials might represent suitable therapeutic pulp protection materials for minimally invasive and atraumatic restorative treatments., (Copyright © 2018 The Academy of Dental Materials. Published by Elsevier Inc. All rights reserved.)

Objectives: The aim of this investigation was to give insights into the impact of carbohydrate-electrolyte drinks on the likely capacity of enamel surface dissolution and the influence of human saliva exposure as a biological protective factor., Materials and Methods: The pH, titratable acidity (TA) to pH 7.0, and buffer capacity (β) of common beverages ingested by patients under physical activity were analyzed. Then, we randomly distributed 50 specimens of human enamel into 5 groups. Processed and natural coconut water served as controls for testing three carbohydrate-electrolyte drinks. In all specimens, we measured surface microhardness (Knoop hardness numbers) and enamel loss (profilometry, µm) for baseline and after simulated intake cycling exposure model. We also prepared areas of specimens to be exposed to human saliva overnight prior to the simulated intake cycling exposure. The cycles were performed by alternated immersions in beverages and artificial saliva. ANOVA two-way and Tukey HDS tests were used., Results: The range of pH, TA, and β were 2.85 - 4.81, 8.33 - 46.66 mM/L and 3.48 - 10.25 mM/L × pH, respectively. The highest capacity of enamel surface dissolution was found for commercially available sports drinks for all variables. Single time human saliva exposure failed to significantly promote protective effect for the acidic attack of beverages., Conclusions: In this study, carbohydrate-electrolyte drinks usually consumed during endurance training may have a greater capacity of dissolution of enamel surface depending on their physicochemical proprieties associated with pH and titratable acidity., Competing Interests: No potential conflict of interest relevant to this article was reported.

Objectives: Enamel resin infiltrants are biomaterials able to treat enamel caries at early stages. Nevertheless, they cannot prevent further demineralization of mineral-depleted enamel. Therefore, the aim of this work was to synthesize and incorporate specific hydroxyapatite nanoparticles (HAps) into the resin infiltrant to overcome this issue., Methods: HAps were prepared using a hydrothermal method (0h, 2h and 5h). The crystallinity, crystallite size and morphology of the nanoparticles were characterized through XRD, FT-IR and TEM. HAps were then incorporated (10wt%) into a light-curing co-monomer resin blend (control) to create different resin-based enamel infiltrants (HAp-0h, HAp-2h and HAp-5h), whose degree of conversion (DC) was assessed by FT-IR. Enamel caries lesions were first artificially created in extracted human molars and infiltrated using the tested resin infiltrants. Specimens were submitted to pH-cycling to simulate recurrent caries. Knoop microhardness of resin-infiltrated underlying and surrounding enamel was analyzed before and after pH challenge., Results: Whilst HAp-0h resulted amorphous, HAp-2h and HAp-5h presented nanorod morphology and higher crystallinity. Resin infiltration doped with HAp-2h and HAp-5h caused higher enamel resistance against demineralization compared to control HAp-free and HAp-0h infiltration. The inclusion of more crystalline HAp nanorods (HAp-2h and HAp-5h) increased significantly (p<0.05) the DC., Significance: Incorporation of more crystalline HAp nanorods into enamel resin infiltrants may be a feasible method to improve the overall performance in the prevention of recurrent demineralization (e.g. caries lesion) in resin-infiltrated enamel., (Copyright © 2016 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.)

Aim: The use of fluoride-releasing materials could be compromised due to aging and might also be influenced by other ordinary sources of fluoride. The aim of the present study was to investigate the aging effect on caries development around resin-modified glass ionomer cement (RMGIC) restorations and the influence of fluoride dentifrice use in this process under the oral environment., Methods: A clinical study was performed in two phases of 14 days each. A total of 16 volunteers wore palatal devices containing dental slabs restored with either a composite resin or RMGIC, either aged or unaged by thermocycling. To simulate a clinical situation of high caries risk, the slabs were exposed to a 20% sucrose solution 10 times per day via the in situ model, where non-fluoride or a fluoride dentifrice was used. Integrated demineralization was determined by cross-sectional microhardness at both margins of the restoration: enamel and dentin., Results: For enamel, higher demineralization around the composite restorations was observed, regardless of dentifrice or aging. For dentin, higher demineralization was observed around the aged composite restorations regardless of the dentifrice type used., Conclusions: The RMGIC restorations provided more enhanced protection against secondary caries for dentin under aging, and the fluoride dentifrice used in this condition had either no clinically relevance or only a minimal effect., (© 2015 Wiley Publishing Asia Pty Ltd.)

This study evaluated if Carbon dioxide (CO2) (λ 10.6 μm) laser irradiation combined with acidulated phosphate fluoride gel application (APF gel) enhances "CaF2" uptake by demineralized enamel specimens (DES) and inhibits enamel lesion progression. Thus, two studies were conducted and DES were subjected to APF gel combined or not with CO2 laser irradiation (11.3 or 20.0 J/cm(2), 0.4 or 0.7 W) performed before, during, or after APF gel application. In study 1, 165 DES were allocated to 11 groups. Fluoride as "CaF2 like material" formed on enamel was determined in 100 DES (n = 10/group), and the surface morphologies of 50 specimens were evaluated by scanning electron microscopy (SEM) before and after "CaF2" extraction. In study 2, 165 DES (11 groups, n = 15), subjected to the same treatments as in study 1, were further subjected to a pH-cycling model to simulate a high cariogenic challenge. The progression of demineralization in DES was evaluated by cross-sectional microhardness and polarized light microscopy analyses. Laser at 11.3 J/cm(2) applied during APF gel application increased "CaF2" uptake on enamel surface. Laser irradiation and APF gel alone arrested the lesion progression compared with the control (p < 0.05). Areas of melting, fusion, and cracks were observed. CO2 laser irradiation, combined with a single APF application enhanced "CaF2" uptake on enamel surface and a synergistic effect was found. However, regarding the inhibition of caries lesion progression, no synergistic effect could be demonstrated. In conclusion, the results have shown that irradiation with specific laser parameters significantly enhanced CaF2 uptake by demineralized enamel and inhibited lesion progression.

Objective: The aim of this study was to evaluate the efficiency of oxalic acid (BisBlock) on restorations of non-carious cervical lesions., Materials and Methods: One operator placed 90 restorations randomly divided into two groups in 20 patients under cotton rolls isolation: Control Group-two-step etch-and-rinse adhesive technique; and Experimental Group-two-step etch-and-rinse adhesive technique with oxalic acid pretreatment after acid-etched dentin. The restorative adhesive system used was XP Bond/Durafill. The restorations were directly assessed by two independent examiners, using the modified United States Public Health Service (USPHS) criteria at the baseline and 4 years. Data were statistically analyzed using the Fisher and McNemar tests (p < 0.05)., Results: Fifteen patients (75%) were available for recall after 4 years. The McNemar test detected significant differences within the Experimental Group between the baseline and 4-year evaluations for retention (p < 0.05). For the Control Group, there was no significant difference (p > 0.05) between the periods. The Fisher test showed no statistically significant difference between the groups for all other criteria (p > 0.05)., Conclusion: After 4 years of service, the use of oxalic acid did not influence the clinical performance of restorations when it was used under composite resin restorations.

Purpose: To evaluate the use of oxalic acid in restorations of noncarious cervical lesions., Materials and Methods: Twenty volunteers of both sexes between 24 and 55 years old, with at least two lesions that were restored with the techniques to be evaluated, were selected. Ninety teeth were randomly divided into two groups: group 1, two-step etch-and-rinse adhesive technique (control) and group 2, pretreatment with oxalic acid followed by the application of a two-step etch-and-rinse adhesive system. The adhesive system used was XP Bond (Dentsply) and the restorative composite resin was Durafill (Heraeus Kulzer). A modified USPHS method was employed for the clinical evaluation, taking into account the following criteria: retention (R), marginal integrity (MI), marginal discoloration (MD), postoperative sensitivity (S), caries (C), and anatomic form (AF). Clinical assessments were conducted by two examiners at baseline and after 6 months, 1 and 2 years., Results: After two years, the results of clinically satisfactory restorations (Alpha and Bravo) obtained for the control and experimental groups were: R (90.9%/93.33%), MI (100%/100%), MD (100%/100%), S (100%/100%), C (100%/100%), AF (100%/100%)., Conclusion: Over a 2-year period, the use of oxalic acid as an agent of dentin pretreatment did not influence the clinical performance of restorations in noncarious cervical lesions.

Streptococcus mutans is an oral bacterium considered to play a major role in the development of dental caries. This study aimed to investigate the prevalence of S. mutans in active and arrested dentine carious lesions of children with early childhood caries and to examine the expression profile of selected S. mutans genes associated with survival and virulence, within the same carious lesions. Dentine samples were collected from 29 active and 16 arrested carious lesions that were diagnosed in preschool children aged 2-5 years. Total RNA was extracted from the dentine samples, and reverse transcription quantitative real-time PCR analyses were performed for the quantification of S. mutans and for analyses of the expression of S. mutans genes associated with bacterial survival (atpD, nox, pdhA) and virulence (fabM and aguD). There was no statistically significant difference in the prevalence of S. mutans between active and arrested carious lesions. Expression of the tested genes was detected in both types of carious dentine. The pdhA (p = 0.04) and aguD (p = 0.05) genes were expressed at higher levels in arrested as compared to active lesions. Our findings revealed that S. mutans is part of the viable microbial community in active and arrested dentine carious lesions. The increase in expression of the pdhA and aguD genes in arrested lesions is likely due to the unfavourable environmental conditions for microbial growth, inherent to this type of lesions., (© 2016 S. Karger AG, Basel.)

Background: Ultraconservative removal of carious tissue is becoming increasingly highlighted for management of deep caries lesions, and combined with an antimicrobial photochemistry-based treatment modality (PACT), this approach can be enhanced favoring dental tissue repair and preservation. The aim was to investigate the effectiveness of PACT using a light emitting diode (LED) associated with a photosensitizer toluidine blue ortho (TBO) on deep caries lesions., Methods: For that, a single blind, randomized, controlled, split-mouth clinical trial where 45 patients with at least two deep carious lesions on permanent posterior teeth was performed. The primary intervention was deep caries lesion management with disinfection of remaining dentin tissue using PACT. Bacterial counts were measured following treatments as the main outcome. The remaining dentinal samples of each lesion were treated with either non-PACT-control or PACT. The PACT procedure were characterized by 100 μg mL(-1) TBO followed by 94J cm(-2) LED irradiation. Samples of dentin were collected before and immediately after treatments for microbiological analysis of total viable bacteria, mutans streptococci and Lactobacillus spp. counts. Microbial reduction was data were submitted to unpaired t test (α=5%)., Results: PACT led to statistically significant reductions in mutans streptococci (1.08 ± 1.20 log), Lactobacillus spp. (1.69 ± 1.37 log), and total viable bacteria (1.07 ± 1.01 log) compared to the control, which showed log reductions respectively of 0.05 ± 0.49, 0.52 ± 0.89, and 0.47 ± 0.77 for the same microorganisms., Conclusion: Dentin from deep carious lesions treated with PACT showed a decrease in cariogenic microbial load., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Background: Insoluble polysaccharide (IP) has been associated with caries prevalence in young children. However, the power of IP to predict ECC needs to be demonstrated., Aims: To assess the relationships between early childhood caries (ECC) and extracellular insoluble polysaccharides (IP) in dental plaque, sugar exposure and cariogenic microorganisms., Design: Visible plaque on maxillary incisors was recorded, followed by caries diagnosis in 65 preschoolers (3-4 years) at baseline and after 1 year. Plaque was collected for mutans streptococci (MS), total microorganism (TM) and lactobacilli (LB) enumerations in selective media, as well as for IP analysis, which was later assessed by colorimetry. Sugar/sucrose exposure was assessed by a diet chart., Results: Positive correlations were found among the prevalence of caries and MS, TM, LB, solid sucrose and visible dental plaque. Additionally, children with IP concentrations in dental plaque higher than 2.36 μg/mg (odds ratio-OR=6.8), with visible plaque on maxillary incisors (OR=4.3), harbouring LB (OR=13) and exposed to solid sugar more than twice/day (OR=5) showed higher risk of developing caries (p<0.05)., Conclusion: Extracellular insoluble polysaccharides, solid sugar/sucrose, visible dental plaque and cariogenic microorganisms could predict caries development, partially explaining the ECC pattern., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

This study aimed to evaluate the effects of repeated CO2 laser applications on the inhibition of enamel demineralization. Sixty-five human dental enamel slabs were randomly assigned to the following groups (n = 13): control (C), one application of the CO2 laser (L1), two applications of the CO2 laser (L2), three applications of the CO2 laser (L3), and four applications of the CO2 laser (L4). Enamel slabs were irradiated by a 10.6-μm CO2 laser operating at 5 J/cm(2). The slabs were subjected to a pH-cycling regimen and then analyzed by FT-Raman spectroscopy, energy-dispersive X-ray fluorescence spectrometry (EDXRF), cross-sectional micro-hardness, and scanning electron microscopy (SEM). Statistical analysis was performed using ANOVA and Tukey tests (p < 0.05). FT-Raman spectroscopy showed a reduced carbonate content for L1, L3, and L4 groups when compared to C (p < 0.05). The EDXRF data showed no statistical differences between the control and irradiated groups for calcium and phosphorus components (p > 0.05). Cross-sectional micro-hardness data showed a statistically significant difference between the control and all irradiated groups (p < 0.05), but no difference was found among the irradiated groups (p > 0.05) up to 30-μm depth. A tendency of lower demineralization occurred in deeper depths for L3 and L4 groups. The SEM results showed that with repeated applications of the CO2 laser, a progressive melting and recrystallization of the enamel surface occurred. Repeated irradiations of dental enamel may enhance the inhibition of enamel demineralization.

Objective: The purpose of this study was to evaluate the influence of erbium-doped: yttrium-aluminum-garnet (Er:YAG) laser parameters and different degrees of demineralization on morphological features, diameter, and depth of prepared cavities., Background Data: Minimally invasive dentin caries removal has been recommended. Ablation of deep caries lesions using Er:YAG laser should preserve remaining demineralized dentin; however, the influence of the degree of mineralization of this substrate had not been entirely described., Materials and Methods: A randomized, factorial design was used to study the effects of two factors. Laser parameter was tested at two levels (250 mJ/4 Hz vs. 200 mJ/2 Hz) and degree of demineralization was tested at four levels (control, two-four-eight cycles). Twelve slabs of human dentin were divided into four groups according to the number of cycles induced by pH-cycling: G1, zero cycles; G2, two cycles, G3, four cycles, and G4, eight cycles. An Er:YAG laser was used at an output energy of 250 mJ/4 Hz and 200 mJ/2 Hz for all groups, for 10 sec at 12 mm distance focus/object. Circumference and depth of the cavities were measured on scanning electron microscopy (SEM) images using image analysis software. The mean values were subjected to two way analysis of variance (ANOVA) and Tukey tests., Results: When using 250 mJ/4 Hz, the mean values of circumferential area increased significantly in relation to control (503.54 μm(2)) with increasing demineralization level (eight cycles) (555.45 μm(2)). Regardless of the demineralization level, there was also significant statistical difference in the studied measurements of the cavities when 250 mJ/4 Hz and 200 mJ/2 Hz were used. SEM also showed that laser cavity preparations left no smear layer, and the dentinal tubules were clear., Conclusions: The circumferential area and depth measurements were affected by laser parameter and demineralization level (eight cycles). Energy level output represents a relevant factor for increased circumferential area and depth measurements. High demineralized artificially caries-affected dentin may also imply higher ablation. Appropriated parameter of laser pulse frequency/power density for demineralized dentin should be used for effective less-invasive caries treatment.

Context: Epigallocatechin-3-gallate (EGCG) is a flavonoid extracted from green tea that demonstrated antimicrobial activity., Aims: To evaluate the efficacy of EGCG 0.5%, 1%, and 2% concentrations as an antimicrobial solution in dentin caries-like lesions induced in a bacterial-based in vitro model., Materials and Methods: Twenty-five human dentin specimens were submitted to a microbial-based caries model by immersion in brain heart infusion (BHI) broth inoculated with Streptococcus mutans UA159, for 5 days. After the demineralization period, the specimens were randomly divided into groups: Group I: 0.9% saline solution; Group II: 2% chlorhexidine digluconate; Group III: 0.5% EGCG; Group IV: 1% EGCG; and Group V: 2% EGCG. After the treatments, carious dentin samples were harvested from dentin specimens and analyzed by colony-forming unit (CFU) counts. Data were analyzed by ANOVA and Tukey's test., Results: Log reduction values (SD, CFU.mg(-1)) for Groups I-V were: 5.02 (0.16), 3.96 (0.43), 4.74 (0.26), 4.89 (0.56), and 4.91 (0.40), respectively. There was no statistical difference between the EGCG concentrations and saline solution (P > 0.05). Furthermore, there was no statistical difference between EGCG concentrations (P > 0.05). However, there was a statistically significant difference between the chlorhexidine digluconate group and the other groups (P < 0.05)., Conclusion: EGCG at the studied concentrations were not effective in eliminating S. mutans from dentin caries-like lesions.

Objectives: This study assessed the effect of three commercial dentifrices with different fluoride-containing compounds in controlling the progression of dentin loss using an in vitro erosion-abrasion model., Materials and Methods: Dentin specimens were randomized into four groups (n = 10): control (no F), Elmex (1,400 ppm AmF), Meridol (1,400 ppm AmF/SnF2), and Crest Pro-Health (1,100 ppm SnF2). The dentin specimens were submitted to cycles of demineralization (HCl 0.01 M for 60 s), remineralization (artificial saliva for 60 min), and immersion in 1:3 w/w of dentifrice/artificial saliva, followed by toothbrushing (150 brushing strokes). The cycle was repeated three times daily for 5 days. Surface loss was quantified by stylus profilometry. Data were submitted to one-way ANOVA and Tukey's tests (p < 0.05)., Results: Wear (μm ± SD) was control 4.1 ± 1.2, Elmex 3.7 ± 1.5, Meridol 1.3 ± 0.4, and Crest Pro-Health 2.1 ± 0.7. Therefore, all products (except Elmex) produced statistically significantly less mineral loss (p < 0.05) when compared with the control., Conclusion: None of the dentifrices avoided the erosive-abrasive process; however, SnF2-containing dentifrices were effective in statistically significantly reducing dentin loss., Clinical Relevance: Scientific literature shows evidence that fluoride can strengthen dental tissue against erosive acid damage. However, the beneficial effect of different fluorides present in commercial dentifrices is questionable. Thus, a determination of an effective fluoride dentifrice may be beneficial in the reduction of the erosive process in patients with gastric disorders.

Purpose: The purpose of this study was to analyze the erosive potential of processed and fresh orange juice on human enamel., Methods: Sixty enamel slabs, incubated in human saliva to develop acquired pellicle, were exposed to processed and freshly squeezed juice from oranges and lime oranges. Daily erosive cycles were performed by immersing the slabs in the juices for 20 minutes over five days. During the intervals, the samples were immersed in artificial saliva. The pH, titratable acidity (TA), and buffer capacity (β) of the juices were determined. Analysis of variance and Tukey's tests were used to compare the percentage of surface hardness loss and the amount of wear between groups., Results: The ranges of pH, TA, and β were 3.66 to 3.75, 3.33 to 110 mmol/L, and 2.98 to 40.97 mmol/L × pH, respectively. A similar erosive potential was found for all groups, except for the lime orange juices (P<.05)., Conclusion: Both processed and freshly squeezed orange juices were erosive to enamel. However, the lime orange juice was acidless and, therefore, not able to produce any significant changes in enamel.

Recurrent caries at the tooth-restoration margins is the main reason for composite failure. Fluoride-releasing nanohybrid composite resin may reduce the recurrent caries rates. A fluoride-releasing resin (FCR) and non-fluoride-releasing resin (CR) were tested using an in situ model. Demineralization (ΔS), ion release and surface roughness of composite specimens were determined. The F concentration in the group FCR was higher than the CR group. ΔS (Mean ± SD) was 2579 ± 1582 and 1705 ± 1292, respectively, for FCR and CR. Surfaces roughness was altered by biofilm accumulation. The hybrid fluorated restorative composites containing nanoparticles have a slight anticaries action without alteration of surface smoothness of the material.

Context: Non-carious cervical lesions are usually associated with dentin hypersensitivity. The use of oxalic acid in restorations of these lesions could be beneficial in relieving pain., Aims: To evaluate the use of oxalic acid in restorations of non-carious cervical lesions., Settings and Design: A randomized clinical trial., Subjects and Methods: One operator placed 90 restorations in 20 volunteers of both sexes, with at least two lesions to be restored with the techniques: Control - Restoration with total-etch technique and Experimental - Restoration with pretreatment with oxalic acid followed by application of adhesive system. The restorative adhesive system used was XP Bond/Durafill. The restorations were directly assessed by two independent examiners using a modified United States Public Health Service (USPHS) method at baseline, 6 and 12 months, taking into account the following criteria: Retention (R), marginal integrity (MI), marginal discoloration (MD), postoperative sensitivity (S), caries (C), and anatomic form (AF)., Statistical Analysis Used: The data were statistically analyzed using the Fisher exact and McNemar tests. The level of significance was set at 5%., Results: After 1 year, the results of restorations clinically satisfactory obtained for the control and experimental group respectively were: R (97% / 89%), MI (100% / 100%), MD (100% / 100%), S (100% / 100%), C (100% / 100%), and AF (100% / 100%)., Conclusions: The use of oxalic acid as an agent of dentin pretreatment did not influence the clinical performance of restorations in non-carious cervical lesions after 1 year.

Objective: This study investigated the effect of phosphoric acid concentration on microshear bond strength (μSBS) of an etch-and-rinse adhesive system to demineralized irradiated enamel., Background Data: Er:YAG laser irradiation may increase acid resistance of enamel; however, its use is associated with reduced bonding effectiveness., Materials and Methods: Three experimental etching agents and one bonding agent were fabricated. Enamel pretreatment was tested in two levels (bur and laser) and phosphoric acid was tested in four levels (control and at 35, 45, or 55%). Commercially available phosphoric acid and a bonding agent were used as control. Enamel samples were submitted to a pH-cycling model to induce demineralization. Half of the exposed demineralized enamel area was prepared with diamond bur and half was prepared with an Er:YAG laser (λ=2.94 μm, 300 mJ, 2 Hz). Specimens were randomly allocated to receive different acid etching concentrations and either the experimental or the commercial adhesive system. Microshear bond strength and the adhesive remnant index (ARI) scores were determined. μSBS's data were evaluated by two way analysis of variance (ANOVA) and Tukey's test. Kruskal-Wallis followed by Dunn's method and Mann-Whitney test were used for ARI comparisons (α=5%)., Results: For μSBS, no significant difference among the groups was found, either for phosphoric acid concentration or surface preparation. For ARI scores, statistically higher resin retention was found for lased groups (p<0.001)., Conclusions: The increase of phosphoric acid concentration did not impair bond strength regardless of surface preparation; however, increased retention was found when demineralized enamel was prepared with laser.

Aim: This in situ study assessed the effects of adhesive systems containing or not fluoride and/or the antibacterial monomer 12-methacryloyloxydodecylpyridinium bromide (MDPB) on the microbiological composition of dental biofilm and enamel demineralization., Materials and Methods: During two phases of 14 days, ten volunteers wore intraoral palatal appliances containing two slabs of human enamel according to a double-blind, crossover design. The slabs were randomly restored using a composite resin and one of the following adhesive systems: All-Bond SE(TM) (self-etch, fluoride/MDPB free adhesive, AB) and Clearfl Protect Bond (self-etch containing fluoride and MDPB adhesive, CB). The biofilm formed on the slabs was analyzed with regard to total and mutans streptococci and lactobacilli counts. Demineralization represented by integrated area of hardness × lesion depth Delta S ( ΔS) was determined on enamel by analysis of cross-sectional microhardness, at 20 and 70 μm from the restoration margin. Data were analyzed by ANOVA., Results: No statistically significant difference was found either in enamel demineralization or in the microbiological composition of dental biofilm., Conclusion: All adhesive systems containing or not fluoride and/or MDPB tested were unable to inhibit secondary caries in the in situ model used in the present research.

Objective: This in vitro study aimed to evaluate the effect of a low intensity diode laser (λ=808 nm; 60 J/cm2) associated with stannous fluoride on the inhibition of dentin erosion by assessing percentage of superficial hardness loss (%SHL) and calcium release into the acid solution., Materials and Methods: Human root dentin slabs were assigned to eight groups (n=10), according to treatments (control, stannous fluoride, diode laser therapy, and the combination of stannous fluoride and laser therapy), and acid challenge (hydrochloridric or citric acid). All slabs were subjected to a previous 2 h acquired pellicle formation; laser and fluoride treatments were performed according to the groups. Subsequently, the slabs were exposed to erosive challenge (0.01 M hydrochloridric acid or citric acid 1% for 60 sec). Additionally, calcium released into the acid solution during erosive challenge was analyzed by photometric test. Data were analyzed by ANOVA followed by Tukey's test (p<0.05)., Results: Mean values (±SD) for %SHL of treated groups did not present statistically significant differences, regardless of the erosive challenge. However, in relation to released calcium concentration, groups treated with laser presented statistically significant lower calcium loss under hydrochloridric acid challenge (p<0.001). To groups under citric acid attack, only the combination of treatments (p=0.037) was able to show a protective effect on dentin., Conclusions: Under the conditions of this study, 808 nm diode laser with or without stannous fluoride could effectively reduce dentin surface loss under both acid exposures. Only calcium concentration analysis was sensitive enough to measure the effects under the tested conditions.

Dental disorders, such as caries, periodontal and endodontic diseases are major public health issues worldwide. In common, they are biofilm-dependent oral diseases, and the specific conditions of oral cavity may develop infectious foci that could affect other physiological systems. Efforts have been made to develop new treatment routes for the treatment of oral diseases, and therefore, for the prevention of some systemic illnesses. New drugs and materials have been challenged to prevent and treat these conditions, especially by means of bacteria elimination. "Recent progresses in understanding the etiology, epidemiology and microbiology of the microbial flora in those circumstances have given insight and motivated the innovation on new therapeutic approaches for the management of the oral diseases progression". Some of the greatest advances in the medical field have been based in nanosized systems, ranging from the drug release with designed nanoparticles to tissue scaffolds based on nanotechnology. These systems offer new possibilities for specific and efficient therapies, been assayed successfully in preventive/curative therapies to the oral cavity, opening new challenges and opportunities to overcome common diseases based on bacterial biofilm development. The aim of this review is to summarize the recent nanotechnological developments in the drug delivery field related to the prevention and treatment of the major biofilm-dependent oral diseases and to identify those systems, which may have higher potential for clinical use.

This study utilized the confocal Raman microspectroscopy (CRM) technique for the first time to investigate the degree of the penetration of toluidine blue-orto (TBO) in artificial caries lesions produced by two distinct caries-inducing models. The dentin specimens (n = 10) were divided into three groups: control, in vitro and in situ. Thereafter, the lesion depth and the demineralization level were evaluated by cross-sectional microhardness (CSMH). CRM mapping across the dentin surface was assessed after the dye application. The CSMH and CRM data were analyzed by t-test and ANOVA, respectively (P < 0.05). The values of the lesion depth and the demineralization areas were higher for in situ samples (P < 0.05). The TBO penetration values (μm) for the control, in vitro and in situ groups were 44.8 ± 5.6, 46.1 ± 4.5 and 51.2 ± 8.5, respectively. There were no statistically significant differences among the groups (P > 0.05). The rate of TBO penetration was detected up to about <50 μm and the demineralization level did not influence the results. These results have showed promising parameters to develop new protocols for deep caries lesions management using photodynamic antimicrobial chemotherapy., (© 2013 The American Society of Photobiology.)

The aim of this study was to determine the erosive potential of hydrogen peroxide (HP) containing mouthwash on dentin assessed by Focus variation three-dimensional (3D) microscopy. Twenty dentin slabs were selected and randomly allocated into two groups (n = 10): DW--Distilled water (pH = 7.27) and HP-1.5% (pH = 3.78). Each specimen was cyclically demineralized (4 × 60 s/day, 10 days) with HP or DW and brushed 3×/day (200 g, 150 strokes--toothpaste with 1,450 ppmF as NaF). Between the challenges, the specimens were exposed to artificial saliva. Afterward, dentin loss was analyzed using focus variation 3D microscopy, and the data were submitted to unpaired t-test (α = 0.05). Statistically significant difference was found between the mean wear rate (μm, ±SD) of HP (1.98 ± 0.51) and DW (1.45 ± 0.39). The results suggest that the use of HP-containing mouthwash associated to brushing may increase the risk of tissue loss and focus variation 3D microscopy may be used as a technique for quantifying dental wear., (Copyright © 2013 Wiley Periodicals, Inc.)

Nanotechnology has been applied to dental materials as an innovative concept for the development of materials with better properties and anticaries potential. In this review we discuss the current progress and future applications of functional nanoparticles incorporated in dental restorative materials as useful strategies to dental caries management. We also overview proposed antimicrobial and remineralizing mechanisms. Nanomaterials have great potential to decrease biofilm accumulation, inhibit the demineralization process, to be used for remineralizing tooth structure, and to combat caries-related bacteria. These results are encouraging and open the doors to future clinical studies that will allow the therapeutic value of nanotechnology-based restorative materials to be established., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

An excessively acidic diet results in the progressive deterioration of dental health, with functional, esthetic, and biological consequences. Previously, rehabilitation required placing numerous full crowns and root canal treatments; however, with improved adhesive techniques, a more conservative approach may be utilized to preserve tooth structure. This article describes 2 cases that utilized conservative dental treatments (involving direct composite resins with minimal preparation of the tooth structure) to treat eroded dentition induced by lemon sucking.

This study evaluated the effect of a 2% chlorhexidine-based disinfectant (CHX) on the short-term resin-dentin bond strength of a self-etch adhesive system to human dentin with different mineral contents. Dentinal mineralization was tested at 4 levels (sound, and after 2, 4, or 8 days of demineralization-remineralization cycles) and disinfectant at 2 levels [deionized water (DW, negative control) and CHX]. Dentin demineralization induced by pH-cycling was characterized by cross-sectional hardness (CSH). Each dentin surface was divided into halves, one treated with DW and the other with CHX (5 minutes). Each surface was bonded with a self-etch adhesive system and restored. The specimens were sectioned and subjected to microtensile bond testing. CSH and microtensile bond strength (µTBS) data were analyzed by regression analysis and ANOVA-Tukey tests (α = 5%), respectively. The groups treated with CHX resulted in mean µTBS similar to those found for the groups in which the dentin was exposed to DW (p = 0.821). However, mean µTBS were strongly influenced by dentin mineralization (p < 0.05): the bond strength found for sound dentin was lower than that found for dentin cycled for 8 days, which was even lower than the bond strengths for dentin cycled for 2 or 4 days. The results suggest that the degree of dentin demineralization affects the bond strength of self-etching adhesives, but the use of CHX does not modify this effect.

Secondary caries remains the main reason for dental restoration failure. Replacement of failed restorations accounts for 50%-70% of all restorations performed. Antibacterial adhesives could inhibit biofilm acids at tooth-restoration margins, and calcium phosphate (CaP) ions could remineralize tooth lesions. The objectives of this study were to: (1) incorporate nanoparticles of silver (NAg), quaternary ammonium dimethacrylate (QADM), and nanoparticles of amorphous calcium phosphate (NACP) into bonding agent; and (2) investigate their effects on dentin bonding and microcosm biofilms. An experimental primer was made with pyromellitic glycerol dimethacrylate (PMGDM) and 2-hydroxyethyl methacrylate (HEMA). An adhesive was made with bisphenol-A-glycerolate dimethacrylate (BisGMA) and triethylene glycol dimethacrylate (TEGDMA). NAg was incorporated into primer at 0.1 wt %. The adhesive contained 0.1% NAg and 10% QADM, and 0%-40% NACP. Incorporating NAg into primer and NAg-QADM-NACP into adhesive did not adversely affect dentin bond strength (p > 0.1). Scanning electron microscopy showed numerous resin tags, and transmission electron microscopy revealed NAg and NACP in dentinal tubules. Viability of human saliva microcosm biofilms on primer/adhesive/composite disks was substantially reduced via NAg and QADM. Metabolic activity, lactic acid, and colony-forming units of biofilms were much lower on the new bonding agents than control (p < 0.05). In conclusion, novel dental bonding agents containing NAg, QADM, and NACP were developed with the potential to kill residual bacteria in the tooth cavity and inhibit the invading bacteria along tooth-restoration margins, with NACP to remineralize tooth lesions. The novel method of combining antibacterial agents (NAg and QADM) with remineralizing agent (NACP) may have wide applicability to other adhesives for caries inhibition., (Copyright © 2012 Wiley Periodicals, Inc.)

Unlabelled: Abstract Objective: The aim of the present study was to examine the size and shape of Streptococcus mutans bacterial cells of infected dentin substrate subjected to photodynamic therapy (PDT) using atomic force microscopy (AFM)., Background Data: New trends in the application of AFM have been developed in the field of dentistry, making AFM a useful technique in high resolution imaging of biological structures and processes., Materials and Methods: PDT was completed using an efficient light-emitting diode source (LED - λ=620-660 nm) with total light dose of 94 J/cm(2) in the presence of the photosensitizer toluidine blue O (TBO). Dentin specimens were immersed in brain heart infusion (BHI) broth inoculated with S. mutans for 5 days to induce caries in vitro. After demineralization, the samples were subjected to a series of treatments in which carious dentin infected by S. mutans was exposed to 0.9% sodium chlorite (NaCl) solution (control) for 10 min, or subjected to PDT-TBO photosensitizer followed by light exposure (energy density of 94 J/cm(2))., Results: Three-dimensional (3-D) images and cross-sectional measurements showed rod and diplococcic cell shapes. Photoinactivated bacterial cells did not differ from the control with respect to their cross-sectional shape, but they did show a reduction in size., Conclusions: Photodynamic therapy decreased the diameter of S. mutans cells and AFM may be used as a technique for bacterial cell analysis.

Objectives: Secondary caries at the restoration margins remains the main reason for failure. Although calcium phosphate (CaP) composites are promising for caries inhibition, there has been no report of CaP composite to inhibit caries in situ. The objectives of this study were to investigate the caries-inhibition effect of nanocomposite containing nanoparticles of amorphous calcium phosphate (NACP) in a human in situ model for the first time, and to determine colony-forming units (CFU) and Ca and P ion concentrations of biofilms on the composite restorations., Methods: NACP with a mean particle size of 116 nm were synthesized via a spray-drying technique. Two composites were fabricated: NACP nanocomposite, and control composite filled with glass particles. Twenty-five volunteers wore palatal devices containing bovine enamel slabs with cavities restored with NACP or control composite. After 14 days, the adherent biofilms were collected for analyses. Transverse microradiography determined the enamel mineral profiles at the margins, and the enamel mineral loss ΔZ was measured., Results: NACP nanocomposite released Ca and P ions and the release significantly increased at cariogenic low pH (p<0.05). Biofilms on NACP nanocomposite contained higher Ca (p=0.007) and P ions (p=0.005) than those of control (n=25). There was no significant difference in biofilm CFU between the two composites (p>0.1). Microradiographs showed typical subsurface lesions in enamel next to control composite, but much less lesion around NACP nanocomposite. Enamel mineral loss ΔZ (mean±sd; n=25) around NACP nanocomposite was 13.8±9.3 μm, much less than 33.5±19.0 μm of the control (p=0.001)., Significance: Novel NACP nanocomposite substantially reduced caries formation in a human in situ model for the first time. Enamel mineral loss at the margins around NACP nanocomposite was less than half of the mineral loss around control composite. Therefore, the Ca and P ion-releasing NACP nanocomposite is promising for caries-inhibiting restorations., (Copyright © 2012 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.)

Objectives: Secondary caries is the main reason for restoration failure, and replacement of the failed restorations accounts for 50-70% of all restorations. Antibacterial adhesives could inhibit residual bacteria in tooth cavity and invading bacteria along the margins. Calcium (Ca) and phosphate (P) ion release could remineralize the lesions. The objectives of this study were to incorporate nanoparticles of silver (NAg) and nanoparticles of amorphous calcium phosphate (NACP) into adhesive for the first time, and to investigate the effects on dentin bond strength and plaque microcosm biofilms., Methods: Scotchbond multi-purpose adhesive was used as control. NAg were added into primer and adhesive at 0.1% by mass. NACP were mixed into adhesive at 10%, 20%, 30% and 40%. Microcosm biofilms were grown on disks with primer covering the adhesive on a composite. Biofilm metabolic activity, colony-forming units (CFU) and lactic acid were measured., Results: Human dentin shear bond strengths (n=10) ranged from 26 to 34 MPa; adding NAg and NACP into adhesive did not decrease the bond strength (p>0.1). SEM examination revealed resin tags from well-filled dentinal tubules. Numerous NACP infiltrated into the dentinal tubules. While NACP had little antibacterial effect, NAg in bonding agents greatly reduced the biofilm viability and metabolic activity, compared to the control (p<0.05). CFU for total microorganisms, total streptococci, and mutans streptococci on bonding agents with NAg were an order of magnitude less than those of the control. Lactic acid production by biofilms for groups containing NAg was 1/4 of that of the control., Significance: Dental plaque microcosm biofilm viability and acid production were greatly reduced on bonding agents containing NAg and NACP, without compromising dentin bond strength. The novel method of incorporating dual agents (remineralizing agent NACP and antibacterial agent NAg) may have wide applicability to other dental bonding systems., (Copyright © 2012 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.)

Various methods have been applied to evaluate the effect of erosion and abrasion. So, the aim of this study was to check the applicability of stylus profilometry (SP), surface hardness (SH) and focus-variation 3D microscopy (FVM) to the analysis of human enamel and dentin subjected to erosion/abrasion. The samples were randomly allocated into four groups (n = 10): G1-enamel/erosion, G2-enamel/erosion plus abrasion, G3-dentin/erosion, and G4-dentin/erosion plus abrasion. The specimens were selected by their surface hardness, and they were subjected to cycles of demineralization (Coca-Cola®-60 s) and remineralization (artificial saliva-60 min). For groups G2 and G4, the remineralization procedures were followed by toothbrushing (150 strokes). The above cycle was repeated 3×/day during 5 days. The samples were assessed using SH, SP, and FVM. For each substrate, the groups were compared using an unpaired t-test, and Pearson correlation coefficients were calculated (α = 5%). For enamel, both profilometry technique showed greater surface loss when the erosion and abrasion processes were combined (P <0.05). The correlation analysis did not reveal any relationships among SH, SP, and FVM to G2 and G4. There were significant correlation coefficients (-0.70 and -0.67) for the comparisons between the FVM and SH methods in enamel and dentin, respectively, in G1 and G3. Choosing the ideal technique for the analysis of erosion depends on the type of dental substrate. SP was not sufficiently sensitive to measure the effects on dentin of erosion or erosion/abrasion. However, SP, FVM and SH were adequate for the detection of tissue loss and demineralization in enamel., (Copyright © 2012 Wiley Periodicals, Inc.)

Altering the structure of the enamel surface around the orthodontic bracket by reducing its content of carbonate and phosphate resulting from application of CO(2) laser may represent a more effective strategy in preventing caries in this region. This study aimed at determining whether irradiation with a CO(2) laser combined with fluoride-releasing bonding material could reduce enamel demineralization around orthodontic brackets subjected to cariogenic challenge. Ninety bovine enamel slabs were divided into five groups (n = 18): non-inoculated brain-heart infusion broth group, non-fluoride-releasing composite resin (NFRCR--control group), resin-modified glass ionomer cement (RMGIC), CO(2) laser + Transbond (L+NFRCR) and CO(2) laser + Fuji (L+RMGIC). Slabs were submitted to a 5-day microbiological caries model. The Streptococcus mutans biofilm formed on the slabs was biochemically and microbiologically analysed, and the enamel Knoop hardness number (KHN) around the brackets was determined. The data were analysed by ANOVA and Tukey tests (α = 0.05). Biochemical and microbiological analyses of the biofilm revealed no statistically significant differences among the groups. Lased groups presented the highest KHN means, which statistically differed from NFRCR; however, no difference was found between these lased groups. RMGIC did not differ from NFRCR which presented the lowest KHN mean. The CO(2) laser (λ = 10.6 μm; 10.0 J/cm(2) per pulse) use with or without F-bonding materials was effective in inhibiting demineralization around orthodontic brackets. However, no additional effect was found when the enamel was treated with the combination of CO(2) laser and an F-releasing material.

Purpose: The purpose of this 1-year follow-up study was to evaluate the behavior/progression of early carious lesions (active noncavitated carious lesions) by surface and type of tooth in early childhood., Methods: A total of 179 3-and 4-year-old preschoolers took part in this study. Clinical examinations were conducted by a calibrated examiner using a mirror, ball-ended probe, gauze for cleaning and drying of teeth, and artificial light. The World Health Organization criteria, with an added measurement of early carious lesions (ECLs), were employed for the caries examinations. Descriptive statistics and logistic regression were used in the statistical analysis., Results: After a 1-year follow-up, the study population developed 1.60 ± 1.64 new carious lesions. Children with caries activity at baseline showed much higher risks of developing new lesions than caries-free children (odds ratio=17.3 for ECL development, OR=24.5 for cavitations/fillings). Most ECLs remained active/unchanged after 1 year, whereas approximately 36% were arrested. Approximately 10% of the ECLs became cavitated, were filled, or were missing due to caries at follow-up. ECLs turned into cavities or fillings more frequently in the posterior region., Conclusion: This study's findings support the conservative management of ECLs since, after 1 year, the majority of lesions were active/unchanged or were arrested on the smooth surfaces of primary teeth.

Contamination between incremental layers of a composite resin restoration can occur during surgical procedures. The present study sought to evaluate how two decontamination treatments affected the shear bond strength between layers of a saliva-contaminated composite resin surface. Forty disks of a nanohybrid composite resin were prepared and divided into four groups (n = 10). The surfaces of all specimens (except for samples in Group 1, the positive control) were contaminated with human saliva. For the negative control samples (Group 2), no decontamination was performed. For Group 3 samples, acid etching was performed and adhesive was applied. For Group 4, surfaces were roughened with a diamond bur prior to acid etching and adhesive application. The specimens were submitted to a shear bond strength test, and the data were analyzed using one-way ANOVA and Tukey tests (α = 0.05). No significant differences were detected between the mean shear bond strengths of samples in Groups 1, 3, and 4 (p < 0.05). Shear bond strength was significantly reduced in Group 2 samples (p < 0.05). Acid etching and the application of adhesive improved shear bond strength, producing values similar to those in the positive control group.

Background: The prevalence of early childhood caries (ECC) is high in developing countries; thus, sensitive methods for the early diagnosis of ECC are of prime importance to implement the appropriate preventive measures., Aim: To investigate the effects of the addition of early caries lesions (ECL) into WHO threshold caries detection methods on the prevalence of caries in primary teeth and the epidemiological profile of the studied population., Design: In total, 351 3- to 4-year-old preschoolers participated in this cross-sectional study. Clinical exams were conducted by one calibrated examiner using WHO and WHO + ECL criteria. During the exams, a mirror, a ball-ended probe, gauze, and an artificial light were used. The data were analysed by Wilcoxon and Mc-Nemar's tests (α=0.05)., Results: Good intra-examiner Kappa values at tooth/surface levels were obtained for WHO and WHO+ECL criteria (0.93/0.87 and 0.75/0.78, respectively). The dmfs scores were significantly higher (P<0.05) when WHO+ECL criteria were used. ECLs were the predominant caries lesions in the majority of teeth., Conclusions: The results strongly suggest that the WHO+ECL diagnosis method could be used to identify ECL in young children under field conditions, increasing the prevalence and classification of caries activity and providing valuable information for the early establishment of preventive measures., (© 2011 The Authors. International Journal of Paediatric Dentistry © 2011 BSPD, IAPD and Blackwell Publishing Ltd.)

Unlabelled: Several photosensitizers have been used against oral bacteria without standardization. Singlet oxygen ((1)O(2)) is an aggressive chemical species that can kill cells through apoptosis or necrosis., Objective: to compare the antimicrobial activity of photodynamic therapy (PDT) with different photosensitizers at the same concentration against Streptococcus mutans. In addition, the (1)O(2) production of each photosensitizer was determined. The photosensitizers (163.5 μM) methylene blue (MB), toluidine blue ortho (TBO) and malachite green (MG) were activated with a light-emitting diode (LED; λ=636 nm), while eosin (EOS), erythrosine (ERI) and rose bengal (RB) were irradiated with a curing light (λ=570 nm). Light sources were operated at 24 J cm(-2). For each photosensitizer, 40 randomized assays (n=10 per condition) were performed under one of the following experimental conditions: no light irradiation or photosensitizer, irradiation only, photosensitizer only or irradiation in the presence of a photosensitizer. After treatment, serial dilutions of S. mutans were seeded onto brain heart infusion agar to determine viability in colony-forming units per milliliter (CFU mL(-1)). Generation of (1)O(2) was analyzed by tryptophan photooxidation, and the decay constant was estimated. Results were analyzed by one-way ANOVA and the Tukey-Kramer test (p<0.05). PDT with irradiation in the presence of the photosensitizers TBO and MG was effective in reducing S. mutans counts by 3 and 1.4 logs, respectively (p<0.01), compared to their respective untreated controls. MB generated 1.3 times more (1)O(2) than TBO, and both produced significantly higher concentrations of singlet oxygen than the other photosensitizers. Since in vitro bulk (1)O(2) production does not indicate that (1)O(2) was generated in the bacterial activity site, the bactericidal action against S. mutans cannot be related to in vitro singlet O(2) generation rate. In vitroS. mutans-experiments demonstrated TBO as the only photosensitizer that effectively reduced 99.9% of these microorganisms., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Aim: The effect of photodynamic antimicrobial chemotherapy (PACT) on oral biofilms was evaluated., Methods: Biofilms formed in vitro were treated with sensitizer (S) and/or light (L) in the test (S+L+) and control (S-L-, S+L-, S-L+) groups. Additionally, 21 volunteers wore intraoral devices and the biofilms formed on each side of the device were referred to as S+L+ or S-L- groups., Results: Significant decreases in the viability of in vitro biofilms were observed after PACT. PACT was ineffective in inhibiting multi-species biofilms formed in situ., Conclusion: PACT was effective on in vitro biofilms and was ineffective on in situ biofilms., (Copyright © 2012 S. Karger AG, Basel.)

Aim: The aim of this study was to evaluate a very short-term in vitro and in situ effect of 2% chlorhexidine-digluconate-based (CHX) cavity cleanser on the disinfection of dentin demineralized by cariogenic bacteria., Materials and Methods: Human dentin slabs were randomly allocated and used in 2 distinct phases, in vitro and in situ, for obtaining demineralized dentin. In vitro, the slabs (n=15) were immersed for 5 days in BHI broth inoculated with Streptococcus mutans CTT 3440. In situ, a double-blind design was conducted in one phase of 14 days, during which 20 volunteers wore palatal devices containing two human dental dentin slabs. On 5(th) day in vitro and 14(th) day in situ, the slabs were allocated to the two groups: Control group (5 μl of 0.9% NaCl solution) and CHX group (5 μl of 2% chlorhexidine digluconate solution, Cavity Cleanser™ BISCO, Schaumburg, IL, EUA), for 5 minutes. The microbiological analyses were performed immediately before and after the treatments., Results: The log reductions means found for CHX treatment on tested micro organisms were higher when compared to Control group either in vitro or in situ conditions., Conclusions: Our results showed that CHX was effective in reducing the cultivable microbiota in contaminated dentin. Furthermore, although the use of chlorhexidine-digluconate-based cavity disinfectant did not completely eliminate the viable microorganisms, it served as a suitable agent to disinfect tooth preparations.

Increasing rates of non-carious cervical lesions due to dental erosion, exposure of dentinal tubules, and hypersensitivity to environmental stimuli have led to the development of new prevention strategies. This study evaluated the effects of a low-intensity diode laser (λ = 808 nm) on the dentinal chemical composition and prevention of demineralization. In addition, the study monitored temperature changes during the course of irradiation. Forty dentin specimens were randomly allocated into four groups (n = 10): G1 - No treatment (control), G2 - irradiated with 15 J/cm(2), G3 - irradiated with 30 J/cm(2), and G4 - irradiated with 60 J/cm(2). Each specimen was partially covered with nail varnish, treated according to the group irradiation levels, and exposed to an erosive challenge (1.0 M hydrochloric acid) for 5 min. Afterwards, dentin loss was profilometrically analyzed and examined by scanning electron microscopy (SEM) combined with energy dispersive X-ray (EDX). Intrapulpal temperatures were measured during the dentin irradiation. One-way ANOVA and Tukey tests (p < 0.05) were performed to assess differences. For all irradiated groups, intrapulpal temperature changes were less than 3°C. The G2 group showed statistically significant differences when compared to the other groups, representing the lowest temperature increase. A quantitative element analysis via EDX did not significantly differ (p < 0.05) for Ca, P, F, O, or C between the four groups when measured after irradiation/erosion. The mean wear rates (± SD, μm) were 35.66 ± 7.28; 40.70 ± 5.03; 38.17 ± 10.81 and 25.25 ± 6.87 for G1-G4, respectively. The G4 group statistically differed from all other groups representing the lowest wear rate. These results suggest that dentin irradiation, using a diode laser with levels set at 60 J/cm(2), may induce inhibitory effects on root dentin demineralization without causing any harmful thermal effects. However, the exact mechanism of the action of the laser remains unclear.

Objective: The present study aimed to determine if the addition of fluoride (F) and calcium (Ca) to home-applied 10% carbamide peroxide (CP) bleaching agents reduces mineral loss on the enamel surface and subsurface., Background: Home-applied 10% carbamide peroxide effectively whitens teeth. However, bleaching possibly promotes adverse side effects such as tooth hypersensitivity and morphological and chemical alterations, such reductions in calcium and fluoride, that affect the enamel surface., Methods: Sixty human enamel slabs were selected based on evaluation of their surface microhardness (n = 10) and submitted to the application of either a placebo agent, Whiteness™, Opalescence™, Pola Night,™ or one of two experimental carbamide peroxide gels: the first with 0.2% fluoride added and the second with 0.2% calcium added. The gel was applied for 6 h/day for 14 days. Samples were submitted to FT-Raman spectroscopy to evaluate surface mineral content before and after treatment. Additionally, cross-sectional microhardness and polarized light microscopy were carried out, to determine enamel subsurface inorganic loss and lesion depth., Results: A significant decrease in mineral content was observed after carbamide peroxide treatment, which resulted in increased lesion depth (p < 0.05). Cross-sectional microhardness assessment and polarized light microscopy demonstrated that all groups (except the placebo) exhibited enamel subsurface mineral loss; however, the inorganic deficit could be effectively controlled by the addition of F and Ca to the experimental bleaching agents., Conclusions: The addition of F and Ca to home-applied bleaching agents may reduce enamel mineral loss.

Consuming a highly acidic diet can lead to erosion or excessive wear of dental hard tissues, resulting in the need for oral rehabilitation. Previously, a severely eroded dentition could be rehabilitated only by extensive crown and bridge placement or by removable partial dentures. However, developments in adhesive dentistry have made it possible to restore the esthetics and function of eroded teeth in a minimally invasive manner. This case report presents a conservative, multidisciplinary approach to restoring severe wear due to dental erosion using proper techniques and materials.