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Valle Mandriole is one of the two last remaining freshwater wetlands in the coastal area of Ravenna (NE Italy). In 2011, a management technique that involves the complete drainage of the southern portion of Valle Mandriole during summer has been undertaken. In the present study, the effects of this artificial drying on the benthic macroinvertebrate fauna were assessed using a beyond before-after-control-impact (beyond BACI) sampling design. Macroinvertebrates dwelling on macrophytes and in bare sediments were sampled in the impact location and in four control locations, two times before and two times after the drying period. Simultaneously, water samples were collected to monitor chemical properties potentially affecting the studied organisms. Biological and chemical data were analysed by multivariate statistical methods. The statistical analysis did not detect any significant effect of the management action on the benthic macroinvertebrates or on the water chemical and physical properties. This contrasts with some previous results, suggesting that the effects of a management strategy based on draining completely dry and then reflooding a wetland area are site specific. However, it is necessary to consider that the present study does have some limitations, in particular, the differences between impact and control locations and the timing of the sampling. The highest biodiversity was observed in one small and isolated control location; this highlights how maintaining, protecting, restoring and even creating small ponds may play an important role in biodiversity conservation. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to evaluate the effect of surface pretreatment with 37% phosphoric acid on the enamel bond strength of different universal adhesives. Methods: One hundred and sixty bovine permanent mandibular incisors freshly extracted were used as a substitute for human teeth. The materials tested in this study included 6 universal adhesives, and 2 self-etch adhesives as control. The teeth were assigned into 2 groups: In the first group, etching was performed using 37% phosphoric acid for 30 seconds. In the second group, no pretreatment agent was applied. After adhesive application, a nanohybrid composite resin was inserted into the enamel surface by packing the material into cylindrical-shaped plastic matrices. After storing, the specimens were placed in a universal testing machine. The normality of the data was calculated using the Kolmogorov-Smirnov test. Analysis of variance (ANOVA) was applied to determine whether significant differences in debond strength values existed among the various groups. Results: Groups with phosphoric acid pretreatment showed significantly higher shear bond strength values than groups with no enamel pretreatment (p<0.001). No significant variation in shear strength values was detected when comparing the different adhesive systems applied onto enamel after orthophosphoric acid application (p>0.05). Conclusions: All adhesives provide similar bond strength values when enamel pretreatment is applied even if compositions are different. Bond strength values are lower than promised by manufacturers. [ABSTRACT FROM AUTHOR]

In the present study, we evaluated the influence of bovine enamel exposure to acidic drinks (Coca-Cola, Coca-Cola Company, Milano, Italy, pH = 2.37) on shear bond strength of three sealants (Fissurit; Grandio Seal and Admira Fusion—Voco Gmbh, Cuxhaven, Germany). For each sealant, two adhesive techniques were tested to investigate the impact of the adhesive application on shear bond strength of sealants after immersion in acidic drink and in the control: Group 1—Control: enamel surface was not in contact with acid drinks, acid etching application and self-adhesive technique for fissure sealant; Group 2—enamel surface was not in contact with acid drinks, acid etching, and adhesive applications, an etch-and-rinse technique for fissure sealant; Group 3—enamel surface was immersed in acid drink, acid etching application and self-adhesive technique for fissure sealant; Group 4—enamel surface was immersed in acid drink, acid etching, and adhesive applications, an etch-and-rinse technique for fissure sealant. For each specimen, the sealant composite resin was applied to the enamel surface and tested with a universal testing machine. Shear bond strength was measured in MPa and with an optical microscope to determine failure modes, quantified with adhesive remnant index (ARI). Enamel acidification variably influenced bond strength values of the different sealants. When no enamel pretreatment was applied, no significant differences were found among the sealants (p > 0.05). However, the mere application of acid etching without adhesive procedures resulted in lower bond strength (p < 0.001). The acid pretreatment affected significantly the bond strength of all sealants tested (p < 0.001), but no significant differences were recorded between the subgroups. [ABSTRACT FROM AUTHOR]

The aim of the present in vitro study was to evaluate the protective effect of self-assembling peptide P11-4 (Curodont™ Protect/Credentis) on enamel erosion produced by a soft-drink, by using Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). Thirty human incisors were equally and randomly assigned to 6 groups. Group 1: intact enamel, group 2: soft drink, group 3: Curodont™ Protect applied, group 4: Curodont™ Protect applied + soft drink, group 5: soft drink + Curodont™ Protect applied, group 6: soft drink + Curodont™ Protect applied + soft drink. Specimens were observed through atomic force microscopy (AFM). The root mean-square roughness (Rrms) was obtained from the AFM images and the differences in the averaged values among the groups were analyzed by Shapiro-Wilk test in order to assess the normality of the distribution. Parametric ANOVA and post hoc Tuckey test were performed to assess the differences between the different groups. After demineralization process, enamel demonstrated a high degree of surface porosity. This morphological aspect was reflected in the increase of Rrms values. No significant differences (p > 0.05) were reported between intact enamel and enamel only treated with P11-4 and between eroded enamel and enamel treated with P11-4 and then demineralized. However significant differences (p < 0.05) were recorded when comparing softened enamel with softened enamel further remineralized with biomimetic self-assembling peptides and enamel treated with the protective paste between two acid attacks. The use of P11-4 remineralizing may offer a degree of protection from enamel erosion. SCANNING 38:344-351, 2016. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the in vitro effect of a casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste (GC Tooth Mousse- TM, GC Corporation, Tokyo, Japan) on preventing enamel erosion, by using Atomic Force Microscopy (AFM). 30 human incisors, were equally assigned to 6 groups: intact enamel, enamel + soft drink, enamel + TM, enamel + TM + soft drink, enamel + soft drink + TM, enamel + soft drink + TM + soft drink. Specimens were observed through atomic force microscopy (AFM). The most common topographical parameters were determined, such as the surface roughness (Rrms). The use of soft drink on intact enamel has roughened the surface of the sample. The application of the CPP-ACP paste on non-treated enamel made the surface smoother. A significant decrease in roughness was seen after remineralization with CPP-ACP paste. Significant differences were recorded when comparing softened enamel with softened enamel remineralized with CPP-ACP paste. Comparing eroded enamel with demineralized/remineralized specimens, the application of a CPP-ACP paste leads to a significant reduction in roughness values. AFM images of enamel surface treated with CPP-ACP resulted in less morphological changes of the tooth substrate when compared with the only eroded enamel surface morphology; thus, indicating that CPP-ACP paste promoted remineralization. Specimens' surface roughness remained similar regardless that the protective agent is used before or after exposure to coke or between two demineralizing cycles. The results confirmed the effectiveness of the CPP-ACP paste on preventing enamel erosion produced by soft drinks. SCANNING 37:327-334, 2015. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The aim of the present in vitro study was to evaluate the morphology of bleached enamel surface followed by the application of different protective pastes. Specimens were prepared from 50 human incisors free of caries and defects. The bleaching procedure was performed with 35% hydrogen peroxide (Perfect Bleach Office+). For the remineralization treatment, different protective pastes (Tooth Mousse, MI Paste Plus, Remin Pro, and Profluorid Varnish) were evaluated. Specimens were randomly assigned to 10 groups of 5 specimens each. The specimens were analyzed under scanning electron microscopy. The superficial morphology of enamel was examined and scored as follows: 0, enamel with smooth surface morphology; 1, enamel with slight irregularities; 2, enamel with moderate irregularities; 3, enamel with accentuated irregularities. The photomicrographs were evaluated in a double-blind manner by three examiners, previously calibrated. Results were analyzed by a Kruskal-Wallis nonparametric test, at the significance level of 0.05. Dunn method posttest was applied for multiple comparisons. A different superficial morphology was observed among control group specimens and specimens treated with bleaching agent and protective pastes (p < 0.05). Enamel bleached showed pronounced surface changes and irregularities, significantly different from other groups except for groups 8 (enamel + Perfect Bleach Office+ + Remin Pro) and 10 (enamel + Perfect Bleach Office+ + Profluorid Varnish) (p > 0.05). The application of the tested pastes after bleaching is effective on repairing enamel surface morphology, demonstrating a higher efficacy for the CPP-ACP products compared to fluoridated ones. SCANNING 38:221-226, 2016. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Direct pulp capping covers the exposed surface of the pulp to maintain its vitality and preserve its functional and biologic activity. The aim of the present study was to compare the biocompatibility effects of seven different pulp-capping materials in vitro: Dycal®, Calcicur®, Calcimol LC®, TheraCal LC®, ProRoot MTA®, MTA-Angelus®, and Biodentine®. Using the Transwell insert methodology by Alamar blue test, we evaluated the cytocompatibility of the above mentioned materials towards murine odontoblasts cells (MDPC-23) at three different times (24, 48, and 72 h). For additional control, the cell viability at 72 hours was also assessed by MTT assay. Morphological analysis of murine odontoblasts was assessed by Confocal Laser Scanning Microscope. The results indicate significantly different biocompatibility among materials with different composition. Biodentine® and mineral trioxide aggregate (MTA)-based products showed lower cytotoxicity, varying from calcium hydroxide-based materials, which exhibited higher cytotoxicity. Although our findings are limited to in vitro conditions, the observation that Biodentine® caused a cytotoxic effect similar to MTA suggests that it may be considered an alternative in pulp-capping treatment, as calcium hydroxide-based materials present higher cytotoxic effects. [ABSTRACT FROM AUTHOR]

Background: The objective of the present study was to compare solubility and pH of 6 direct pulp capping materials. Methods: Specimens of each material - i.e., Dycal, Calcicur, Calcimol LC, TheraCal LC, MTA Angelus and ProRoot MTA - were prepared and immersed in water. Solubility was determined after 24 hours and 2 months and analyzed statistically using a 1-way ANOVA and post hoc Tukey test. pH values were measured 3 and 24 hours after manipulation. Results: All direct pulp capping materials showed low solubility; the pH of tested materials ranged from 10 to 12 and showed a nonsignificant increase/reduction after 24 hours. Conclusions: Within the limitations of this in vitro study, the direct pulp capping materials studied showed different solubility even if no changes were recorded over time. All of the materials showed a very alkaline pH. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of the present study was to investigate the cleaning efficacy of 2 different nickel-titanium (NiTi) rotary systems: a new single system Reciproc compared with the rotary full sequence Mtwo. The amount of debris and the morphology of smear layer were the parameters for the evaluation of the cleanliness of root canals. The null hypothesis of the study was that there would be no significant difference in debris scores and smear layer scores between the 2 systems. Methods: Forty single-rooted freshly extracted teeth were selected and divided into 2 groups. For each group, all root canals were shaped with 2 different NiTi instruments (Mtwo and Reciproc) and irrigated with 5.25% NaOCl and 17% ethylenediaminetetraacetic acid (EDTA) solutions by 3 trained operators. Specimens were fractured longitudinally and prepared for scanning electron microscopy (SEM) analysis at a standard magnification of ×5,000. The presence/absence of smear layer and the presence/absence of debris at the coronal, middle and apical third of each canal were evaluated using two 5-step scales for scores. Numeric data were analyzed using the Kruskal-Wallis and Mann-Whitney U statistical tests, and significance was set at a P value <0.05. Results: This study revealed significant differences among the various groups. The Mtwo group presented significantly lower smear layer scores than the Reciproc group (P<0.01) in the middle and apical third of the canal. Conclusions: Conventional continuous rotary NiTi instruments associated with 5.25% NaOCl and 17% EDTA solutions seem to be better for obtaining clean dentinal canal walls. Reciprocating instruments leave a higher quantity of smear layer which covers dentinal walls and dentinal tubules. [ABSTRACT FROM AUTHOR]

Aim The purposes of this study were to evaluate the effect of surface pretreatment with phosphoric acid on the enamel bond strength of four-one-step self-etch adhesives with different pH values. Material and methods One hundred bovine permanent mandibular incisors were used. The materials used in this study included four-one-step self-etch adhesives with different pH values: Adper™ Easy Bond Self-Etch Adhesive (ph = 0,8-1), Futurabond NR (ph = 1,4), G-aenial Bond (ph = 1,5), Clearfil3S Bond (ph = 2,7). One two-step self-etch adhesive (Clearfil SE Bond/ph = 0,8-1) was used as control. The teeth were assigned into two subgroups according to bonding procedure. In the first subgroup ( n = 50), no pretreatment agent was applied. In the second subgroup ( n = 50), etching was performed using 37% phosphoric acid for 30 s. After adhesive systems application, a nanohybrid composite resin was inserted into the enamel surface. The specimens were placed in a universal testing machine (Model 3343, Instron Corp., Canton, Mass., USA). After the testing procedure, the fractured surfaces were examined with an optical microscope at a magnification of 10× to determine failure modes. The adhesive remnant index (ARI) was used to assess the amount of adhesive left on the enamel surface. Results Descriptive statistics of the shear bond strength and frequency distribution of ARI scores were calculated. Conclusions Enamel pretreatment with phosphoric acid significantly increased bond strength values of all the adhesives tested. No significant differences in bond strength were detected among the four different one-step self-etch adhesives with different pH. Two-step self-etch adhesive showed the highest bond strength. [ABSTRACT FROM AUTHOR]