Effect of iodonium salt and chitosan on the physical and antibacterial properties of experimental infiltrants

Resinous infiltrants are indicated in the treatment of incipient carious lesions, and further development of these materials may contribute to greater control of these lesions. The aim of this study was to analyze the physical and antibacterial properties of experimental infiltrants containing iodonium salt and chitosan. Nine experimental infiltrants were formulated by varying the concentration of the diphenyliodonium salt (DPI) at 0, 0.5 and 1 mol%; and chitosan at 0, 0.12 and 0.25 g%. The infiltrants contained the monomeric base of triethylene glycol dimethacrylate and bisphenol-A dimethacrylate ethoxylate in a 75 and 25% proportion by weight, respectively; 0.5 mol% camphorquinone and 1 mol% ethyl 4-dimethylaminobenzoate. The degree of conversion was evaluated using Fourier transformer infrared spectroscopy, and the flexural strength and elastic modulus using the three-point bending test. Sorption and solubility in water, and antibacterial analysis (minimum inhibitory concentration and minimum bactericidal concentration) were also analyzed. Data was analyzed statistically by two-way ANOVA and Tukey's test (p<0.05), with the exception of the antibacterial test, which was evaluated by visual inspection. In general, the infiltrant group containing 0.5% DPI and 0.12% chitosan showed high values of degree of conversion, higher values of elastic modulus and flexural strength, and lower sorption values in relation to the other groups. Antibacterial activity was observed in all the groups with DPI, regardless of the concentration of chitosan. The addition of DPI and chitosan to experimental infiltrants represents a valid option for producing infiltrants with desirable physical and antibacterial characteristics3

Healthcare Professionals' Views on the Management of Medication Complexities in the Elderly With Mental Health Disorders: A Cross-Sectional Study

Background: Many challenges in elderly pharmacotherapy are identified, including the use of Potentially Inappropriate Medications (PIMs) which may increase the odds of adverse events, especially in elderly patients with mental health disorders (e. g., behavioral, and psychological symptoms of dementia–BPSD, schizophrenia, bipolar disorder). However, information on the knowledge and practice of healthcare professionals (HCPs) about this topic is still scarce. Methods: A cross-sectional study was undertaken from July-October 2019. An online questionnaire was specifically designed and validated for this study. We sought HCPs (physicians, pharmacists, and nurses) worldwide, using (a) social media, via Facebook, Twitter, and LinkedIn; and (b) email contacts of the research team (convenience sample). Either way participants were asked to share on their social media or via e-mail the questionnaires with other HCPs (snowballing sample). The survey assessed two main domains: knowledge and practice. Knowledge was evaluated by self-report (perceived knowledge by a 5-item Likert confidence scale) and using three clinical cases, scored between 0 and 30 points (each one rated from 0 to 10 points; real knowledge). Barriers in clinical practice were evaluated using a 5-item Likert scale judging practitioners' opinion. Results: A total of 165 questionnaires were collected. HCPs were mainly female (n = 114; 69.1%), with a mean age of 35.3 ± 11.3 years old. Seventy-two percent (n = 118) were pharmacists, 21.1% (n = 35) were physicians, and 7.3% (n = 12) nurses. There was a weak correlation, albeit significant, between perceived and real knowledge (r = 0.199; p = 0.001). The mean score of the clinical vignettes regarding elderly patients with dementia and bipolar disorder were 4.59 ± 4.08 and 4.86 ± 2.97 points, respectively. Most HCPs were classified as having an intermediate knowledge (n = 100; 60.6%) about medication complexities in the elderly with mental disorders. Most HCPs agreed that lack of time (81.6%; n = 138), lack of education and training on elderly pharmacotherapy (72.2%; n = 122), and lack of tools adapted to daily practice (61.8%; n = 105) were the main barriers. Conclusions: Most of the HCPs felt confident to manage medication complexities in elder patients with mental disorders, but only a minority obtained a good score in the knowledge assessment test. The main barriers identified included structural barriers (tools unfit for practice) and process barriers (time)

Influence Of Surface Treatments On Enamel Susceptibility To Staining By Cigarette Smoke

Objectives: The purpose of this study was to evaluate the influence of remineralizing agents, including artificial saliva, neutral fluoride, and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), on the susceptibility of bleached enamel to staining by cigarette smoke. Study design: Fifty bovine enamel blocks were randomly divided into five groups (n = 10): G1- bleaching; G2- bleaching and immersion in artificial saliva; G3- bleaching and application of CPP-ACP; G4- bleaching and application of neutral fluoride; and G5- untreated (Control). Teeth were bleached with 35% hydrogen peroxide and treated with the appropriate remineralizing agent. After treatment, all groups were exposed to cigarette smoke. Enamel color measurements were performed at three different times: before treatment (T1), after treatment (bleaching and remineralizing agent) (T2), and after staining (T3), by using the CIE Lab method with a spectrophotometer. The data coordinate L* was evaluated by analysis of repeated-measures PROC MIXED and Tukey-Kramer's test, and the E values were submitted to one-way ANOVA and Tukey's test (a = 0.05). Results: The G1 group did not show any statistically significant difference for L* values between times T1 and T2. The G4 and G5 groups showed lower L* values at T3 compared to T2. No significant differences between the groups were observed for E (after treatment and staining). However, G4 showed a clinically apparent color change. Conclusions: Treatment of bleached enamel with neutral fluoride can contribute to the increased staining of enamel due to cigarette smoke. © Medicina Oral S. L. C.I.F. B 96689336 - eISSN: 1989-5488.54163168Lewinstein, I., Hirschfeld, Z., Stabholz, A., Rotstein, I., Effect of hydrogen peroxide and sodium perborate on the microhardness of human enamel and dentin (1994) J Endod., 20, pp. 61-3McEvoy, S.A., Chemical agents for removing intrinsic stains from vital teeth (1989) I. Technique development. Quintessence Int., 20, pp. 323-8Joiner, A., The bleaching of teeth: a review of the literature (2006) J Dent., 34, pp. 412-9Sulieman, M., An overview of bleaching techniques: I (2004) History, chemistry, safety and legal aspects. Dent Update., 31, pp. 608-10. , 612-4, 616McGuckin, R.S., Babin, J.F., Meyer, B.J., Alterations in human enamel surface morphology following vital bleaching (1992) J Prosthet Dent., 68, pp. 754-60Pinto, C.F., Oliveira, R.D., Cavalli, V., Giannini, M., Peroxide bleaching agent effects on enamel surface microhardness, roughness and morphology (2004) Braz Oral Res., 18, pp. 306-11Berger, S.B., Coelho, A.S., Oliveira, V.A., Cavalli, V., Giannini, M., Enamel susceptibility to red wine staining after 35% hydrogen peroxide bleaching (2008) J Appl Oral Sci., 16, pp. 201-4Setien, V., Roshan, S., Cala, C., Ramirez, R., Pigmentation susceptibility of teeth after bleaching with 2 systems: an in vitro study (2009) Quintessence Int., 40, pp. 47-52Ernst, C.P., Marroquín, B.B., Willershausen-Zönnchen, B., Effects of hydrogen peroxide-containing bleaching agents on the morphology of human enamel (1996) Quintessence Int., 27, pp. 53-6Josey, A.L., Meyers, I.A., Romaniuk, K., Symons, A.L., The effect of a vital bleaching technique on enamel surface morphology and the bonding of composite resin to enamel (1996) J Oral Rehabil., 23, pp. 244-50Attin, T., Kielbassa, A.M., Schwanenberg, M., Hellwig, E., Effect of fluoride treatment on remineralization of bleached enamel (1997) J Oral Rehabil., 24, pp. 282-6Serra, M.C., Cury, J.A., The in vitro effect of glass-ionomer cement restoration on enamel subjected to a demineralization and remineralization model (1992) Quintessence Int., 23, pp. 143-7ten Cate, J.M., Review on fluoride, with special emphasis on calcium fluoride mechanisms in caries prevention (1997) Eur J Oral Sci., 105, pp. 461-5Reynolds, E.C., Cai, F., Cochrane, N.J., Shen, P., Walker, G.D., Morgan, M.V., Fluoride and casein phosphopeptide-amorphous calcium phosphate (2008) J Dent Res., 87, pp. 344-8Cochrane, N.J., Cai, F., Huq, N.L., Burrow, M.F., Reynolds, E.C., New approaches to enhanced remineralization of tooth enamel (2010) J Dent Res., 89, pp. 1187-97Ferreira Sda, S., Araújo, J.L., Morhy, O.N., Tapety, C.M., Youssef, M.N., Sobral, M.A., The effect of fluoride therapies on the morphology of bleached human dental enamel (2011) Microsc Res Tech., 74, pp. 512-6Hamba, H., Nikaido, T., Inoue, G., Sadr, A., Tagami, J., Effects of CPPACP with sodium fluoride on inhibition of bovine enamel demineralization: a quantitative assessment using micro-computed tomography (2011) J Dent., 39, pp. 405-13Weir, A., Westerhoff, P., Fabricius, L., Hristovski, K., von Goetz, N., Titanium dioxide nanoparticles in food and personal care products (2012) Environ Sci Technol., 46, pp. 2242-50Cunha, A.G., De Vasconcelos, A.A., Borges, B.C., Vitoriano Jde, O., Alves-Junior, C., Machado, C.T., Efficacy of in-office bleaching techniques combined with the application of a casein phosphopeptideamorphous calcium phosphate paste at different moments and its influence on enamel surface properties (2012) Microsc Res Tech., 75, pp. 1019- 25Cavalli, V., Rodrigues, L.K., Paes-Leme, A.F., Brancalion, M.L., Arruda, M.A., Berger, S.B., Effects of bleaching agents containing fluoride and calcium on human enamel (2010) Quintessence Int., 41, pp. e157-65Liporoni, P.C., Souto, C.M., Pazinatto, R.B., Cesar, I.C., de Rego, M.A., Mathias, P., Enamel susceptibility to coffee and red wine staining at different intervals elapsed from bleaching: a photoreflectance spectrophotometry analysis (2010) Photomed Laser Surg., 28, pp. S105-9Rotstein, I., Dankner, E., Goldman, A., Heling, I., Stabholz, A., Zalkind, M., Histochemical analysis of dental hard tissues following bleaching (1996) J Endod., 22, pp. 23-5Cakir, F.Y., Korkmaz, Y., Firat, E., Oztas, S.S., Gurgan, S., Chemical analysis of enamel and dentin following the application of three different at-home bleaching systems (2011) Oper Dent., 36, pp. 529-36Kwon, Y.H., Huo, M.S., Kim, K.H., Kim, S.K., Kim, Y.J., Effects of hydrogen peroxide on the light reflectance and morphology of bovine enamel (2002) J Oral Rehabil., 29, pp. 473-7Gomes, M.N., Francci, C., Medeiros, I.S., De Godoy Froes Salgado, N.R., Riehl, H., Marasca, J.M., Effect of light irradiation on tooth whitening: enamel microhardness and color change (2009) J Esthet Restor Dent., 21, pp. 387-94Singh, R.D., Ram, S.M., Shetty, O., Chand, P., Yadav, R., Efficacy of casein phosphopeptide-amorphous calcium phosphate to prevent stain absorption on freshly bleached enamel: An in vitro study (2010) J Conserv Dent., 13, pp. 76-

Estimating the inelasticity with the information theory approach

Using the information theory approach, in both its extensive and nonextensive versions, we estimate the inelasticity parameter $K$ of hadronic reactions together with its distribution and energy dependence from $p\bar{p}$ and $pp$ data. We find that the inelasticity remains essentially constant in energy except for a variation around $K\sim 0.5$, as was originally expected.Comment: 14 pages, 8 figures. Misprints correcte