Synergistic effect between plant extracts and fluoride to protect against enamel erosion: An in vitro study.

Polyphenol-rich solutions, such as plant extracts and teas, can modify the salivary pellicle and improve the protection against dental erosion. In this study, we further explored how these polyphenol-rich plant extracts solutions behave in the presence of fluoride. We distributed enamel specimens into 9 groups (n = 15): Control_No_F- (Deionized water); Control_F- (500 ppm F-), Grape_Seed_No_F- (Grape seed extract), Grape_Seed_F- (Grape seed extract + 500 ppm F-), Grapefruit_Seed_No_F- (Grapefruit seed extract), Grapefruit_Seed_F- (Grapefruit seed extract + 500 ppm F-), Blueberry_No_F- (Blueberry extract), Blueberry_F- (Blueberry extract + 500 ppm F-), and Sn2+/F-_Rinse (commercial solution containing 800 ppm Sn2+ and 500 ppm F-). The specimens were submitted to 5 cycles (1 cycle per day), and each cycle consisted of: salivary pellicle formation (human saliva, 30 min, 37°C), modification of the pellicle (2 min, 25°C), pellicle formation (60 min, 37°C), and an erosive challenge (1 min, citric acid). Between cycles, the specimens were kept in a humid chamber. Relative surface hardness (rSH), relative surface reflection intensity (rSRI) and calcium released to the acid were analysed, using general linear models, and Kruskal-Wallis with post-hoc Dunn's tests. We observed that the presence of fluoride in synergy with the extract solutions provided better protection than the groups containing extract or fluoride only. For rSH, we observed a significant main effect of extracts (F(4,117) = 9.20; p<0.001) and fluoride (F(1,117) = 511.55; p<0.001), with a significant interaction (F(3,117) = 6.71; p<0.001). Grape_Seed_F- showed the best protection, better than fluoride, and Sn2+/F-_Rinse. Calcium results also showed greater protection for the groups containing fluoride, whereas for rSRI, despite a significant interaction between extract and fluoride (F(3,117) = 226.05; p<0.001), the differences between the groups were not as clearly observed. We conclude that polyphenols from plant extracts, when combined with fluoride, improve the protective effect of salivary pellicles against enamel erosion.

Photobiomodulation effect on angiogenic proteins produced and released by dental pulp cells.

OBJECTIVE: To verify the photobiomodulation effect on angiogenic proteins produced and released by dental human pulpal fibroblasts (HPFs). MATERIAL AND METHODS: HPFs were irradiated with 660-nm low-level laser at fluences of 2.5 J/cm2 and 3.7 J/cm2. The control group was not irradiated. MTT, crystal violet, and ELISA assays respectively verified viability, proliferation, and angiogenic protein (supernatant/lysate) at 6 h, 12 h, and 24 h after photobiomodulation. Capillary-like structure formation assay verified functional role. Two-way ANOVA/Tukey's test and ANOVA/Bonferroni's multiple comparisons test respectively verified cell viability/proliferation and intragroup and intergroup comparisons of protein synthesis (p < 0.05). RESULTS: Irradiated and non-irradiated HPFs showed statistically similar cell viability and proliferation pattern. Intragroup comparisons showed similar patterns of protein synthesis for all groups: VEGF-A, VEGF-C, and vascular endothelial growth factor receptor 1 (VEGFR1) increased significantly in the supernatant, while FGF-2 and VEGF-A increased significantly in the lysate. The lower fluence significantly increased BMP-9 (6 h) in the supernatant and VEGFR1 (6 h and 12 h) and VEGF-D (24 h) in the lysate, while the higher fluence significantly increased BMP-9 (6 h) in the supernatant and VEGFR1 (12 h) in the lysate. Regardless of the time, both fluences statistically downregulated placental growth factor (PLGF) and PDGF secretion. Both fluences statistically decreased VEGF-A secretion (24 h) and PLGF production (6 h). CONCLUSION: Photobiomodulation produced stimulatory effects on angiogenic protein secretion by pulp fibroblasts. In terms of photobiomodulation, over time, both fluences significantly increased the secretion of VEGF-A, VEGF-C, and VEGFR1 and significantly upregulated BMP-9 (6 h) in the supernatant; for capillary-like structure formation, the fluence of 2.5 J/cm2 was better than the fluence of 3.7 J/cm2. CLINICAL RELEVANCE: This study results addressed effective photobiomodulation parameters tailored for pulp angiogenesis.

Does photobiomodulation change the synthesis and secretion of angiogenic proteins by different pulp cell lineages?

This study aimed to compare the synthesis and secretion of VEGF-A, VEGF-C, VEGF-D, VEGFR1, VEGFR2, and FGF-2 between pulp fibroblasts from human primary teeth (HPF) and stem cell from human deciduous teeth (SHED) before and after photobiomodulation. HPF were obtained from explant technique and characterized by immunohistochemistry, while SHED were obtained from digestion technique and characterized by flow cytometry. HPF (control group) and SHED were plated, let to adhere, and put on serum starvation to synchronize the cell cycles prior to photobiomodulation. Then, both cell lineages were irradiated with 660-nm laser according to the following groups: 2.5 and 3.7 J/cm2. MTT and crystal violet assays respectively verified viability and proliferation. ELISA Multiplex Assay assessed the following proteins: VEGF-A, VEGF-C, VEGF-D, VEGFR1, VEGFR2, FGF-2, at 6, 12, and 24 h after photobiomodulation, in supernatant and lysate. Two-way ANOVA/Tukey test evaluated cell viability and proliferation, while angiogenic production and secretion values were analyzed by one-way ANOVA (P < .05). Statistically similar HPF and SHED viability and proliferation patterns occurred before and after photobiomodulation (P > .05). HPF exhibited statistically greater values of all angiogenic proteins than did SHED, at all study periods, except for FGF-2 (supernatant; 12 h); VEGFR1 (lysate; non-irradiated; 12 h); and VEGFR1 (lysate; non-irradiated; 24 h). Photobiomodulation changed the synthesis and secretion of angiogenic proteins by HPF. HPF produced and secreted greater values of all tested angiogenic proteins than did SHED before and after irradiation with both energy densities of 2.5 and 3.7 J/cm2.

Could a chelant improve the effect of curcumin-mediated photodynamic antimicrobial chemotherapy against dental intact biofilms?

To our knowledge, there is still no evidence in relation to the combination of curcumin with chelants to improve the effects of antimicrobial photodynamic therapy (aPDT) on complex dental caries biofilms. Therefore, the aim of this study was to evaluate the antimicrobial effect of curcumin-ethylenediaminetetraacetic acid (EDTA)-mediated aPDT on the vitality of intact biofilms of dentin caries microcosms. Biofilms were grown on glass slabs in McBain medium plus 1% sucrose in microaerophily at 37 °C for 5 days. Then, biofilms were treated with associations of 600 µmol L-1 curcumin combined or not with 1% EDTA and 37.5 or 75 J cm-2 LED (455 nm). The vitality was determined by a confocal laser scanning microscopy (CLSM) after staining biofilms with a mixture of 2.5 g L-1 fluorescein diacetate and 0.25 g L-1 ethidium bromide. Statistical analysis was conducted by Kruskal-Wallis and post hoc Dunn's test (P < 0.05). Three treatments were able to reduce the vitality of overall biofilms: curcumin + 75 J cm-2 LED, curcumin-EDTA + 37.5 J cm-2 LED, and curcumin-EDTA + 75 J cm-2 LED. Also, the vitality of inner layers of biofilms was significantly reduced only after the combination of aPDT with EDTA. Therefore, the association of curcumin and EDTA improved the antimicrobial effect of aPDT on dentin caries microcosms, considering the application of lower light densities and deeper layers of biofilms.

Manual vs. rotary instrumentation in endodontic treatment of permanent teeth: A systematic review and meta-analysis.

PURPOSE: To systematically review all studies comparing manual instrumentation with at least one rotary instrument in the preparation of the root canal of permanent human teeth. METHODS: The electronic databases PubMed, EMBASE, LILACS, IBECS and BBO were searched. In vitro studies published until 27 of September, 2016 were included. For statistical analysis, we used the Comprehensive Meta-Analysis software (Biostat), considering P< 0.05 significant. RESULTS: A total of 1,104 articles published until September 27, 2016 were obtained, with 57 meeting the eligibility criteria. The studies were grouped according to the main methodology used (computerized tomography, periapical radiography, image amplification and scanning electron microscope). Due to the wide variability of the methodologies and evaluated parameters, a subgroup analysis was performed based on the evaluated parameter. The meta-analysis revealed that rotary instruments caused a significant reduction in instrumentation time and a smaller change of the canal curvature than manual instruments. The rotary instrumentation presented better results regarding root canal transportation, ability of centralization within the canal path and shaping of the canal. Manual instrumentation performed better with regard to the smear layer and debris production, more instrumented canal surfaces and fewer dentin defects. CLINICAL SIGNIFICANCE: An increasing number of studies have compared the efficiency of manual and rotary instrumentation in endodontic treatment of permanent teeth. This study helps elucidate which method is more efficient in the endodontic treatment of permanent teeth.

Could chlorhexidine be an adequate positive control for antimicrobial photodynamic therapy in- in vitro studies?

BACKGROUND: Chlorhexidine digluconate (CHX) is commonly applied as positive control of new antimicrobials, because it is considered the gold-standard for chemical plaque control. The aim of this study was to compare the effect of treatments with curcumin-mediated aPDT and CHX in relation to the viability of specific microorganism groups in two distinct times (immediately and 24 h later). METHODS: Dentin caries microcosms were grown on bovine dentin discs (37 °C, anaerobiosis) for 3 days in the Active Attachment Amsterdam Biofilm Model. The biofilms were treated with 300 µM curcumin and 75 J.cm-² LED, or 0.06% and 0.12% CHX. Then, total microorganisms, total streptococci, mutans streptococci, and total lactobacilli counts were determined. The statistical analysis was conducted by Kruskal-Wallis and post-hoc Dunn's tests (P < 0.05). RESULTS: Curcumin-mediated aPDT (C + L+), 0.06% and 0.12% CHX reduced mutans streptococci counts (0.19, 0.10 and 0.07 log10 respectively) in the immediate analysis. After 24 h, it was observed a re-growth of microorganisms treated by curcumin-mediated aPDT, whereas both CHX concentrations demonstrated a decrease of the viable microorganisms. CONCLUSION: This study confirmed the substantive effect of CHX and the immediate effect of aPDT. The use of a neutralizer solution was important to block the substantivity of CHX and permit its fair comparison with aPDT, allowing its use as a positive control in further studies.

Effect of palm oil alone or associated to stannous solution on enamel erosive-abrasive wear: A randomized in situ/ex vivo study.

OBJECTIVE: Palm oil has demonstrated preventive potential against initial erosive demineralization in vitro. This in situ study evaluated the effect of palm oil alone or associated with stannous-containing (Sn) solution on preventing enamel loss from an erosive/abrasive challenge. DESIGN: This single-blind, randomized, crossover in situ/ex vivo study was developed in four phases (one per group of five days) with sixteen volunteers. Enamel blocks (n = 256) were allocated to groups according to the treatment: Palm oil; Palm oil plus Sn solution; Sn solution - positive control; and Deionized water - negative control. Half of the enamel blocks of each group was subjected to erosion and the other half to erosion + abrasion. The daily ex vivo protocol consisted of four citric acid immersions (2 min). Before the first and third acid exposure, the blocks were treated with the test solutions (1 drop/block) for 1 min followed by acid immersion and abrasive challenge (toothpaste was applied on all blocks and half were brushed for 15 s/block). Enamel loss was quantified profilometrically and data were analyzed by two-way ANOVA and Tukey's test (p < 0.05). RESULTS: A significant difference was found for type of treatment (p < 0.001); wear condition (p = 0.38) and the treatment x condition interaction (p = 0.33) was non-significant. Palm oil associated or not to Sn solution significantly reduced enamel wear in comparison with the negative control but did not differ from the positive control (p > 0.05). CONCLUSIONS: Palm oil was able to prevent enamel loss under erosive and erosive + abrasive challenges in a similar extend to stannous-containing commercial solution.

Effect of different concentrations and application times of proanthocyanidin gels on dentin erosion.

PURPOSE: To analyze the effect of different concentrations and application times of proanthocyanidin gels on dentin before an erosive challenge in order to evaluate if there is a dose-response or application time-response relationship in the use of these gels for erosion prevention. METHODS: 80 bovine root dentin blocks were randomly and equally divided into 10 groups and treated according to the two factors under study (purified grape seed proanthocyanidin gel concentration and time of application): 0.05P1: 0.05% proanthocyanidin gel during 1 minute; 0.05P5: 0.05% proanthocyanidin gel during 5 minutes; 1P1: 1% proanthocyanidin gel during 1 minute; 1P5: 1% proanthocyanidin gel during 5 minutes; 5P1: 5% proanthocyanidin gel during 1 minute; 5P5: 5% proantho-cyanidin gel during 5 minutes; 10P1: 10% proanthocyanidin gel during 1 minute; 10P5: 10% proanthocyanidin gel during 5 minutes; Control 1: placebo gel during 1 minute; and Control 5: placebo gel during 5 minutes. The gels were applied over dentin blocks once before the first erosive challenge. After that, the blocks were subjected to three erosive cycles per day, during 5 days. Profilometry was used to quantify the dentin loss (µm). Data were analyzed by two-way ANOVA and Fisher's test (P< 0.05). RESULTS: Statistical analysis showed that there was no significant difference between the application times. The different concentrations of proanthocianidin gels presented similar results (P> 0.05). All tested gels resulted in significantly less wear when compared to the placebo gel. CLINICAL SIGNIFICANCE: Grape seed proanthocyanidin gels could be considered as a promising therapy to diminish erosive dentin wear because it may interact with the exposed collagen, enhancing the demineralized organic matrix stabilization, which acts as a barrier against the diffusion of the acids from erosion.

Effect of Proanthocyanidin-enriched extracts on the inhibition of wear and degradation of dentin demineralized organic matrix.

OBJECTIVES: The aim of this study was to evaluate the effect of Cranberry and Grape seed-enriched extract gels in inhibiting wear and degradation of demineralized organic matrix (DOM). DESIGN: 225 dentin specimens obtained from bovine incisors were randomly allocated into 5 groups (n=45): 10% Grape seed extract gel (GSE), 10% Cranberry extract gel (CE), 0.012% Chlorhexidine gel (CX), 1.23% NaF gel (F), and no active compound gel (P, placebo). Before the treatments, samples were demineralized by immersion in 0.87M citric acid, pH 2.3 (36h). Then, the studied gels were applied once over dentin for 1min. Next, the samples were immersed in artificial saliva containing collagenase obtained from Clostridium histolyticum for 5days. The response variable for dentin wear was depth of dentin loss measured by profilometry and for collagen degradation was hydroxyproline determination. Data were analyzed by ANOVA followed by Tukey's test and Pearson Correlation Test (p<0.05). RESULTS: Grape seed extract significantly reduced dentin wear compared to the other groups (p<0.05). Cranberry extract and Chlorhexidine did not differ statistically and were able to reduce wear when compared to NaF and placebo treatments. The hydroxyproline analysis showed that there was no significant difference among groups for all treatments (p<0.05). Correlation analysis showed a significant correlation between the amount of degraded DOM evaluated by profilometry and the determination of hydroxyproline. CONCLUSION: Cranberry extract was able to reduce the dentin wear and collagen degradation, likely due to the proanthocyanidin content and its action. Therefore, Cranberry could be suggested as an interesting natural-based agent to prevent dentin erosion.

Effect of vegetable oils applied over acquired enamel pellicle on initial erosion.

OBJECTIVE: The prevalence of dental erosion has been recently increasing, requiring new preventive and therapeutic approaches. Vegetable oils have been studied in preventive dentistry because they come from a natural, edible, low-cost, and worldwide accessible source. This study aimed to evaluate the protective effect of different vegetable oils, applied in two concentrations, on initial enamel erosion. MATERIAL AND METHODS: Initially, the acquired pellicle was formed in situ for 2 hours. Subsequently, the enamel blocks were treated in vitro according to the study group (n=12/per group): GP5 and GP100 - 5% and pure palm oil, respectively; GC5 and GC100 - 5% and pure coconut oil; GSa5 and GSa100 - 5% and pure safflower oil; GSu5 and GSu100 - 5% and pure sunflower oil; GO5 and GO100 - 5% and pure olive oil; CON- - Deionized Water (negative control) and CON+ - Commercial Mouthwash (Elmex® Erosion Protection Dental Rinse, GABA/positive control). Then, the enamel blocks were immersed in artificial saliva for 2 minutes and subjected to short-term acid exposure in 0.5% citric acid, pH 2.4, for 30 seconds, to promote enamel surface softening. The response variable was the percentage of surface hardness loss [((SHi - SHf) / SHf )×100]. Data were analyzed by one-way ANOVA and Tukey's test (p<0.05). RESULTS: Enamel blocks of GP100 presented similar hardness loss to GSu100 (p>0.05) and less than the other groups (p<0.05). There was no difference between GP5, GC5, GC100, GSa5, GSu100, GSa100, GSu5, GO5, GO100, CON- and CON+. CONCLUSION: Palm oil seems to be a promising alternative for preventing enamel erosion. However, further studies are necessary to evaluate a long-term erosive cycling.

Effect of vegetable oils applied over acquired enamel pellicle on initial erosion

Abstract Objective The prevalence of dental erosion has been recently increasing, requiring new preventive and therapeutic approaches. Vegetable oils have been studied in preventive dentistry because they come from a natural, edible, low-cost, and worldwide accessible source. This study aimed to evaluate the protective effect of different vegetable oils, applied in two concentrations, on initial enamel erosion. Material and Methods Initially, the acquired pellicle was formed in situ for 2 hours. Subsequently, the enamel blocks were treated in vitro according to the study group (n=12/per group): GP5 and GP100 - 5% and pure palm oil, respectively; GC5 and GC100 - 5% and pure coconut oil; GSa5 and GSa100 - 5% and pure safflower oil; GSu5 and GSu100 - 5% and pure sunflower oil; GO5 and GO100 - 5% and pure olive oil; CON− - Deionized Water (negative control) and CON+ - Commercial Mouthwash (Elmex® Erosion Protection Dental Rinse, GABA/positive control). Then, the enamel blocks were immersed in artificial saliva for 2 minutes and subjected to short-term acid exposure in 0.5% citric acid, pH 2.4, for 30 seconds, to promote enamel surface softening. The response variable was the percentage of surface hardness loss [((SHi - SHf) / SHf )×100]. Data were analyzed by one-way ANOVA and Tukey's test (p<0.05). Results Enamel blocks of GP100 presented similar hardness loss to GSu100 (p>0.05) and less than the other groups (p<0.05). There was no difference between GP5, GC5, GC100, GSa5, GSu100, GSa100, GSu5, GO5, GO100, CON− and CON+. Conclusion Palm oil seems to be a promising alternative for preventing enamel erosion. However, further studies are necessary to evaluate a long-term erosive cycling.

In situ effect of a commercial CPP-ACP chewing gum on the human enamel initial erosion.

OBJECTIVE: This study evaluated the in situ rehardening effect of a commercial chewing gum containing casein phosphopeptide - amorphous calcium phosphate (CPP-ACP) on initial erosion lesions. METHODS: Seventy-two human enamel blocks, after selection (initial surface hardness - SHi) and in vitro short-term acidic exposure (cola drink for 3 min - SHd) were randomly assigned to three groups. The factors under study were treatment (3 levels: GI chewing gum with CPP-ACP, GII chewing gum without CPP-ACP and GIII control group without gum) and intraoral period (2 levels: 2 and 24h). Twelve volunteers wore intraoral palatal devices for 24h in 3 crossover phases. On each phase, after 2h the surface hardness was assessed (SHf1) and the blocks were reinserted and the devices were used for additional 22 h (SHf2). In phases of GI and GII volunteers chewed the respective gum during 30 min, for 4 times with an interval of 4h. Percentage of surface hardness recovery (%SHR) was calculated after 2 and 24 h. The data were analysed by repeated measures ANOVA and Tukey's test. RESULTS: Chewing gum with CPP-ACP (2h=50.0%<24h=95.9%) showed higher hardness recovery than chewing gum without CPP-ACP (2h=30.0%<24 h=71.1%) and control (2 h=15.7%<24 h=40.9%) (p<0.05). CONCLUSIONS: The results suggest that saliva increased hardness of softened enamel after the use of conventional chewing gum (GII) and this effect was enhanced by the prolonged intraoral period (24 h) and by the use of CPP-ACP chewing gum (GI). CLINICAL SIGNIFICANCE: Since chewing gum is an alternative to enhance salivary defenses after erosive challenges, CPP-ACP chewing gum might be a supplementary strategy to potentiate the mineral precipitation of initial erosion lesions.

The erosive potential of 1% citric acid supplemented by different minerals: an in vitro study.

PURPOSE: The objective of the present in vitro study was to evaluate the effect of different minerals in combination with 1% citric acid on dental erosion. MATERIALS AND METHODS: Ninety enamel samples were randomly allocated to nine groups (G1: pure 1% citric acid solution [control]; G2: with 1 mM Ca; G3: with 0.047 mM F; G4: with 1 mM Fe; G5: with 1 mM P; G6: with 1 mM Ca and 0.047 mM F; G7: with 1 mM Ca and 1 mM P; G8: with 1 mM Fe and 0.047 mM F; G9: with 1 mM Ca, 1 mM P, 0.047 mM F and 1.0 mM Fe). The samples were subjected to six pH cycles, each consisting of immersion in pure or modified 1% citric acid (1 min) followed by storage in artificial saliva (59 min). Enamel wear was assessed using profilometry. RESULTS: Data were analysed using analysis of variance and Tukey test (P < 0.05). Enamel loss (mean + or - SD) amounted to between 0.87 + or - 0.30 and 1.74 + or - 0.74 microm but did not significantly differ among the groups. CONCLUSIONS: The modification of 1% citric acid with different minerals did not have a protective effect on enamel erosion.

Protective effect of green tea on dentin erosion and abrasion.

OBJECTIVE: This in situ study evaluated the protective effect of green tea on dentin erosion (ERO) and erosion-abrasion (ABR). MATERIAL AND METHODS: Ten volunteers wore intraoral palatal appliances with bovine dentin specimens subjected to ERO or ERO + toothbrushing abrasion performed immediately (ERO+I-ABR) or 30 min after erosion (ERO+30-min-ABR). During 2 experimental 5-day crossover phases, the volunteers rinsed with green tea or water (control, 1 min) between each erosive (5 min, cola drink) and abrasive challenge (30 s, toothbrushing), 4x/day. Dentin wear was measured by profilometry. RESULTS: The green tea reduced the dentin wear significantly for all conditions compared to control. ERO+I-ABR led to significantly higher wear than ERO, but it was not significantly different from ERO+30-min-ABR. ERO+30-min-ABR provoked significant higher wear than ERO, only for the placebo treatment. CONCLUSIONS: From the results of the present study, it may be concluded that green tea reduces the dentin wear under erosive/abrasive conditions.

Protective effect of green tea on dentin erosion and abrasion

OBJECTIVE: This in situ study evaluated the protective effect of green tea on dentin erosion (ERO) and erosion-abrasion (ABR). MATERIAL AND METHODS: Ten volunteers wore intraoral palatal appliances with bovine dentin specimens subjected to ERO or ERO + toothbrushing abrasion performed immediately (ERO+I-ABR) or 30 min after erosion (ERO+30-min-ABR). During 2 experimental 5-day crossover phases, the volunteers rinsed with green tea or water (control, 1 min) between each erosive (5 min, cola drink) and abrasive challenge (30 s, toothbrushing), 4x/day. Dentin wear was measured by profilometry. RESULTS: The green tea reduced the dentin wear significantly for all conditions compared to control. ERO+I-ABR led to significantly higher wear than ERO, but it was not significantly different from ERO+30-min-ABR. ERO+30-min-ABR provoked significant higher wear than ERO, only for the placebo treatment. CONCLUSIONS: From the results of the present study, it may be concluded that green tea reduces the dentin wear under erosive/abrasive conditions.

Chlorhexidine and green tea extract reduce dentin erosion and abrasion in situ.

OBJECTIVES: This in situ/ex vivo study aimed to analyse the impact of possible MMP-inhibitors (chlorhexidine and green tea extract) on dentin wear induced by erosion or erosion plus abrasion. METHODS: Twelve volunteers took part in this cross-over and double-blind study performed in 4 phases of each 5 days. Bovine dentin samples were worn in palatal appliances and subjected to extraoral erosion (4 times/day, Coca-Cola, 5 min) or erosion plus abrasion (2 times/day, fluoride-free toothpaste and electrical toothbrush, 15s/sample). Immediately after each erosion, the appliances were reinserted in the mouth and the oral cavity was rinsed for 60s with: 250 ppm F solution (SnF(2)/AmF, pH 4.5, Meridol-Gaba, Switzerland), 0.12% chlorhexidine digluconate (0.06% chlorhexidine, pH 6.0, Periogard-Colgate, Brazil), 0.61% green tea extract solution (OM24, 100% Camellia Sinensis leaf extract, catechin concentration: 30+/-3%, pH 7.0, Omnimedica, Switzerland) or deionized water (pH 6.0, control). Dentin loss was assessed by profilometry (microm). The data were analysed by two-way repeated measures ANOVA and Bonferroni post hoc test. RESULTS: There was a significant difference between the conditions (EroxEro+Abr, p<0.001) and among the solutions (p<0.001). All solutions (F: 1.42+/-0.34; 1.73+/-0.50, chlorhexidine: 1.15+/-0.26; 1.59+/-0.32, green tea: 1.06+/-0.30; 1.54+/-0.55) significantly reduced the dentin wear when compared to control (2.00+/-0.55; 2.41+/-0.83) for both conditions. There were not significant differences among green tea extract, chlorhexidine and F solutions. CONCLUSIONS: Thus, the possible MMP-inhibitors tested in this study seem to be a promising preventive measure to reduce dentin erosion-abrasion, but their mechanism of action needs to be investigated in further studies.

Light cola drink is less erosive than the regular one: an in situ/ex vivo study.

OBJECTIVE: This in situ/ex vivo study assessed the erosive potential of a light cola drink when compared to a regular one. METHODS: During 2 experimental 14-days crossover phases, eight volunteers wore palatal devices with 2 human enamel blocks. The groups under study were: group light, erosive challenge with light cola drink and group regular, erosive challenge with regular cola drink. During 14 days, erosive challenges were performed extraorally 3X/day. In each challenge, the device was immersed in 150ml of light cola (group light) or regular cola (group regular) for 5min. Erosion was analysed by surface profilometry (microm) and surface microhardness change (%SMH). The data were statistically analyzed using paired t test (p<0.05). RESULTS: Group light (0.6+/-0.2microm) showed significantly lesser wear than group regular (3.1+/-1.0microm). There was no significant difference between the groups for the %SMH (group light -63.9+/-13.9 and group regular -78.5+/-12.7). CONCLUSIONS: The data suggest that the light cola drink is less erosive than the regular one.

Estudio etnográfico de las experiencias de sanar y enfermar en mujeres Mapuche Huilliche del Sector Sur de San Juan de la Costa / Ethnographic study of the experiences of healing and illness in women Mapuche Huilliche of Sector San Juan de la Costa

La presente investigación tiene como objetivo comprender los principales factores socioculturales y sanitarios que motivan a las mujeres Mapuche Huilliche del sector sur de San Juan de la Costa a solucionar sus problemas de salud en la medicina occidental o en la medicina tradicional de su cultura. Para lograr los objetivos planteados se diseñó un proyecto de investigación cualitativa de tipo etnográfica, cuya recopilación de datos fue a través de un trabajo de campo integrando técnicas de recolección de datos adecuadas como entrevistas etnográficas y Focus Group, las cuales fueron analizadas a través del método de Spradley. La selección de la muestra se realizó considerando personas del sexo femenino pertenecientes a tres comunidades indígenas del sector sur de San Juan de la Costa, provincia de Osorno, Chile. Tomando en cuenta estos criterios se identificaron a los informantes claves mediante la técnica de variación máxima definida por Flick, integrando casos en donde nos percatamos que poseían visiones diferentes respecto al tema de investigación dentro de cada comunidad. Finalmente se realizó un total de siete entrevistas en profundidad y un Focus Group. Al llevar a cabo el análisis de los resultados surgieron cuatro temas principales "Percepciones frente a la medicina mapuche","Percepciones frente a la medicina occidental", "Mujer Mapuche Huilliche" y Pertenencia cultural", cada uno de los cuales involucró variados subtemas. Dentro de los resultados se destaca como factor principal de decisión frente al sistema de salud occidental y Mapuche Huilliche, el significado de salud y enfermedad atribuido por su cultura y las condiciones geográficas de aislamiento en las que se encuentran insertas. La etapa final se realizó teniendo como base la Teoría de Madelaine Leininger y su modelo del Sol naciente, integrando los diferentes factores observados en las comunidades que dan forma a su cultura al momento de optar por la medicina occidental o medicina tradicional...

Estudio etnográfico de las experiencias de sanar y enfermar en mujeres Mapuche Huilliche del Sector Sur de San Juan de la Costa / Ethnographic study of the experiences of healing and illness in women Mapuche Huilliche of Sector San Juan de la Costa

La presente investigación tiene como objetivo comprender los principales factores socioculturales y sanitarios que motivan a las mujeres Mapuche Huilliche del sector sur de San Juan de la Costa a solucionar sus problemas de salud en la medicina occidental o en la medicina tradicional de su cultura. Para lograr los objetivos planteados se diseñó un proyecto de investigación cualitativa de tipo etnográfica, cuya recopilación de datos fue a través de un trabajo de campo integrando técnicas de recolección de datos adecuadas como entrevistas etnográficas y Focus Group, las cuales fueron analizadas a través del método de Spradley. La selección de la muestra se realizó considerando personas del sexo femenino pertenecientes a tres comunidades indígenas del sector sur de San Juan de la Costa, provincia de Osorno, Chile. Tomando en cuenta estos criterios se identificaron a los informantes claves mediante la técnica de variación máxima definida por Flick, integrando casos en donde nos percatamos que poseían visiones diferentes respecto al tema de investigación dentro de cada comunidad. Finalmente se realizó un total de siete entrevistas en profundidad y un Focus Group. Al llevar a cabo el análisis de los resultados surgieron cuatro temas principales "Percepciones frente a la medicina mapuche","Percepciones frente a la medicina occidental", "Mujer Mapuche Huilliche" y "Pertenencia cultural", cada uno de los cuales involucró variados subtemas. Dentro de los resultados se destaca como factor principal de decisión frente al sistema de salud occidental y Mapuche Huilliche, el significado de salud y enfermedad atribuido por su cultura y las condiciones geográficas de aislamiento en las que se encuentran insertas. La etapa final se realizó teniendo como base la Teoría de Madelaine Leininger y su modelo del Sol naciente, integrando los diferentes factores observados en las comunidades que dan forma a su cultura al momento de optar por la medicina occidental o medicina ...