Johanna Bierlich, Kniestück, mit Geige

Signatur des Originals: S 36/G0394

Effect Of Fluoride-treated Enamel On Indirect Cytotoxicity Of A16% Carbamide Peroxide Bleaching Gel To Pulp Cells

The aim of this study was to evaluate the possibility of fluoride solutions applied to enamel to protect pulp cells against the trans-enamel and transdentinal cytotoxicity of a 16% carbamide peroxide (CP) bleaching gel. The CP gel was applied to enamel/ dentin discs adapted to artificial pulp chambers (8 h/day) during 1, 7 or 14 days, followed by fluoride (0.05% or 0.2%) application for 1 min. The extracts (culture medium in contact with dentin) were applied to MDPC-23 cells for 1 h, and cell metabolism (MTT assay), alkaline phosphatase (ALP) activity and cell membrane damage (flow cytometry) were analyzed. Knoop microhardness of enamel was also evaluated. Data were analyzed statistically by ANOVA and Kruskal-Wallis tests (a=0.05). For the MTT assay and ALP activity, significant reductions between the control and the bleached groups were observed (p0.05), regardless of fluoride application or treatment days. Flow cytometry analysis demonstrated 30% of cell membrane damage in all bleached groups. After 14 days of treatment, the fluoride-treated enamel presented significantly higher microhardness values than the bleached-only group (p<0.05). It was concluded that, regardless of the increase in enamel hardness due to the application of fluoride solutions, the treated enamel surface did not prevent the toxic effects caused by the 16% CP gel to odontoblast-like cells.242121127Markowitz, K., Pretty painful: Why does tooth bleaching hurt? (2010) Med Hypotheses, 74, pp. 835-840Soares, D.G., Ribeiro, A.P., da Silveira Vargas, F., Hebling, J., de Souza Costa, C.A., Efficacy and cytotoxicity of a bleaching gel after short application times on dental enamel (2012) Clin Oral Investig, , [Epub ahead of print. DOI: 10.1007/s00784-012-0883-1]De Souza Costa, C.A., Riehl, H., Kina, J.F., Sacono, N.T., Hebling, J., Human pulp responses to in-office tooth bleaching (2010) Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 109, pp. e59-e64Coldebella, C.R., Ribeiro, A.P., Sacono, N.T., Trindade, F.Z., Hebling, J., Costa, C.A., Indirect cytotoxicity of a 35% hydrogen peroxide bleaching gel on cultured odontoblast-like cells (2009) Braz Dent J, 20, pp. 267-274Trindade, F.Z., Ribeiro, A.P., Sacono, N.T., Oliveira, C.F., Lessa, F.C., Hebling, J., Trans-enamel and trans-dentinal cytotoxic effects of a 35% HP bleaching gel on cultured odontoblast cell lines after consecutive applications (2009) Int Endod J, 42, pp. 516-524Kina, J.F., Huck, C., Riehl, H., Martinez, T.C., Sacono, N.T., Ribeiro, A.P., Response of human pulps after professionally applied vital tooth bleaching (2010) Int Endod J, 43, pp. 572-580Lima, A.F., Lessa, F.C., Mancini, M.N., Hebling, J., Costa, C.A., Marchi, G.M., Transdentinal protective role of sodium ascorbate against the cytopathic effects of HP released from bleaching agents (2010) Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 109, pp. e70-e76Soares, D.G., Ribeiro, A.P., Sacono, N.T., Coldebella, C.R., Hebling, J., Costa, C.A., Transenamel and transdentinal cytotoxicity of carbamide peroxide bleaching gels on odontoblast-like MDPC-23 cells (2011) Int Endod J, 44, pp. 116-125Lima, A.F., Ribeiro, A.P., Soares, D.G., Sacono, N.T., Hebling, J., de Souza Costa, C.A., Toxic effects of daily applications of 10% carbamide peroxide on odontoblast-like MDPC-23 cells (2013) Acta Odontol Scand, , Epub ahead of print. DOI:10.3109/00016357.2012.762992]Eimar, H., Siciliano, R., Abdallah, M.N., Nader, S.A., Amin, W.M., Martinez, P.P., Hydrogen peroxide whitens teeth by oxidizing the organic structure (2012) J Dent, 40, pp. e25-e33Gökay, O., Müjdeci, A., Algin, E., In vitro peroxide penetration into the pulp chamber from newer bleaching products (2005) Int Endod J, 38, pp. 516-520Meireles, S.S., Santos, I.S., Bona, A.D., Demarco, F.F., A double-blind randomized clinical trial of two carbamide peroxide tooth bleaching agents: 2-year follow-up (2010) J Dent, 38, pp. 956-963Borges, A.B., Samezima, L.Y., Fonseca, L.P., Yui, K.C., Borges, A.L., Torres, C.R., Influence of potentially remineralizing agents on bleached enamel microhardness (2009) Oper Dent, 34, pp. 593-597Borges, A.B., Yui, K.C., D'avila, T.C., Takahashi, C.L., Torres, C.R., Borges, A.L., Influence of remineralizing gels on bleached enamel microhardness in different time intervals (2010) Oper Dent, 35, pp. 180-186Cavalli, 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-e165Cavalli, V., Rodrigues, L.K., Paes-Leme, A.F., Soares, L.E., Martin, A.A., Berger, S.B., Effects of the addition of fluoride and calcium to low-concentrated carbamide peroxide agents on the enamel surface and subsurface (2011) Photomed Laser Surg, 29, pp. 319-325Armênio, R.V., Fitarelli, F., Armênio, M.F., Demarco, F.F., Reis, A., Loguercio, A.D., The effect of fluoride gel use on bleaching sensitivity: A double-blind randomized controlled clinical trial (2008) J Am Dent Assoc, 139, pp. 592-597Kose, C., Reis, A., Baratieri, L.N., Loguercio, A.D., Clinical effects of at-home bleaching along with desensitizing agent application (2011) Am J Dent, 24, pp. 379-382Reis, A., Dalanhol, A.P., Cunha, T.S., Kossatz, S., Loguercio, A.D., Assessment of tooth sensitivity using a desensitizer before light-activated bleaching (2011) Oper Dent, 36, pp. 12-17Read, S.M., Northcote, D.H., Minimization of variation in the response to different proteins of the Coomassie blue G dye-binding assay for protein (1981) Anal Biochem, 116, pp. 53-64Min, K.S., Lee, H.J., Kim, S.H., Lee, S.K., Kim, H.R., Pae, H.O., Hydrogen peroxide induces Heme Oxygenase-1 and dentin sialophosphoprotein m RNA in human pulp cells (2008) J Endod, 34, pp. 983-989Goodis, H.E., Bowles, W.R., Hargreaves, K.M., Prostaglandin E2 enhances bradykinin-evoked iCGRP release in bovine dental pulp (2000) J Dent Res, 79, pp. 1604-1607Markowitz, K., Bilotto, G., Kim, S., Decreasing intradental nerve activity in the cat with potassium and divalent cations (1991) Arch Oral Biol, 36, pp. 1-7Boushell, L.W., Ritter, A.V., Garland, G.E., Tiwana, K.K., Smith, L.R., Broome, A., Nightguard vital bleaching: Side effects and patient satisfaction 10 to 17 years post-treatment (2012) J Esthet Restor Dent, 24, pp. 211-219Sauro, S., Pashley, D.H., Montanari, M., Chersoni, S., Carvalho, R.M., Toledano, M., Effect of simulated pulpal pressure on dentin permeability and adhesion of self-etch adhesives (2007) Dent Mater, 23, pp. 705-71

Caries assessment spectrum treatment: the severity score

Contains fulltext : 190619.pdf (Publisher’s version ) (Closed access)OBJECTIVES: To appraise the feasibility of the caries assessment spectrum and treatment (CAST) severity score according to the formula (F) recommended in the CAST manual. METHODS: Data from an epidemiological survey of 680 schoolchildren (mean age +/- standard deviation: 7.45 +/- 0.91 years), living in a low-income area in Brasilia, were used. The CAST instrument was used for assessing enamel carious lesions (CAST code = 3), dentine carious lesions (CAST codes = 4-7) and tooth loss from caries (CAST code = 8). RESULTS: The prevalence of carious lesions including enamel and dentine in both deciduous and permanent dentitions was 49.41% and 69.12%, respectively. Calculating the CAST severity score per child using F was unsatisfactory because of the undiscriminating weight given for each CAST code. Modification of weights according to the accepted levels of disease severity for individual CAST codes resulted in a new formula (F1), in which the weight given to cavitated dentine lesions was quadrupled in relation to that given to enamel carious lesions; this was different from F, in which the weight given to such lesions was twofold. F1 was able to categorise satisfactorily the study children into one of three levels of dental caries severity: mild (34.1%); moderate (29.5%); or severe (36.4%). CONCLUSION: According to the outcomes of the present appraisal, it was concluded that the numerical score provided by the CAST severity scores allows an overview of the severity of caries disease and the classification of individuals into mild, moderate or severe levels of dental caries when the new formula (F1) is used

Effect Of Low-level Laser Therapy On Odontoblast-like Cells Exposed To Bleaching Agent

The aim of the present study was to evaluate the effect of low-level laser therapy (LLLT) on odontoblast-like MDPC-23 cells exposed to carbamide peroxide (CP 0.01 %-2.21 μg/mL of H2O2). The cells were seeded in sterile 24-well plates for 72 h. Eight groups were established according to the exposure or not to the bleaching agents and the laser energy doses tested (0, 4, 10, and 15 J/cm2). After exposing the cells to 0.01 % CP for 1 h, this bleaching solution was replaced by fresh culture medium. The cells were then irradiated (three sections) with a near-infrared diode laser (InGaAsP-780 ± 3 nm, 40 mW), with intervals of 24 h. The 0.01 % CP solution caused statistically significant reductions in cell metabolism and alkaline phosphate (ALP) activity when compared with those of the groups not exposed to the bleaching agent. The LLLT did not modulate cell metabolism; however, the dose of 4 J/cm2 increased the ALP activity. It was concluded that 0.01 % CP reduces the MDPC-23 cell metabolism and ALP activity. The LLLT in the parameters tested did not influence the cell metabolism of the cultured cells; nevertheless, the laser dose of 4 J/cm2 increases the ALP activity in groups both with and without exposure to the bleaching agent. © 2013 Springer-Verlag London.1

Effects Of Laser Irradiation On Pulp Cells Exposed To Bleaching Agents

The aim of this study was to evaluate the effect of low-level laser therapy (LLLT) on odontoblast-like cells exposed to a bleaching agent. Mouse dental papilla cell-23 cells were seeded in wells of 24-well plates. Eight groups were established according to the exposure to the bleaching agent and LLLT (0, 4, 10 and 15 J cm-2). Enamel-dentin disks were adapted to artificial pulp chambers, which were individually placed in wells containing Dulbecco's modified Eagle's medium (DMEM). A bleaching agent (35% hydrogen peroxide [BA35%HP]) was applied on enamel (15 min) to obtain the extracts (DMEM + BA35%HP components diffused through enamel/dentin disks). The extracts were applied (1 h) to the cells, and then subjected to LLLT. Cell viability (Methyl tetrazolium assay), alkaline phosphatase (ALP) activity, as well as gene expression of ALP, fibronectin (FN) and type I collagen, were evaluated. The bleaching procedures reduced the cell viability, ALP activity and gene expression of dentin proteins. Laser irradiation did not modulate the cell response; except for FN, as LLLT decreased the gene expression of this protein by the cells exposed to the BA35%HP. It can be concluded that BA35%HP decreased the activities of odontoblasts that were not recovered by the irradiation of the damaged cells with low-level laser parameters tested. The aim of the present study was to evaluate the effect of low-level laser therapy (LLLT) on odontoblast-like cells exposed to a bleaching agent. Eight groups were established according to the exposure to the bleaching agent (35% hydrogen peroxide) and LLLT (0, 4, 10, and 15 J cm-2). The bleaching procedures reduced the cell viability, ALP activity, and gene expression of dentin proteins. Laser irradiation did not modulate the cell response; except for FN, since LLLT decreased the gene expression of this protein by the cells exposed to the 35% hydrogen peroxide. © 2013 The American Society of Photobiology.901201206Costa, C.A., Riehl, H., Kina, J.F., Sacono, N.T., Hebling, J., Human pulp responses to in-office tooth bleaching (2010) Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod., 109, pp. e59-e64Dias Ribeiro, A.P., Sacono, N.T., Lessa, F.C., Nogueira, I., Coldebella, C.R., Hebling, J., De Souza Costa, C.A., Cytotoxic effect of a 35% hydrogen peroxide bleaching gel on odontoblast-like MDPC-23 cells (2009) Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod., 108, pp. 458-464De Lima, A.F., Lessa, F.C., Gasparoto Mancini, M.N., Hebling, J., De Souza Costa, C.A., Marchi, G.M., Cytotoxic effects of different concentrations of a carbamide peroxide bleaching gel on odontoblast-like cells MDPC-23 (2009) J. Biomed. Mater. Res. B Appl. 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B, 27, pp. 219-223Khadra, M., Lyngstadaas, S.P., Haanaes, H.R., Mustafa, K., Effect of laser therapy on attachment, proliferation and differentiation of human osteoblast-like cells cultured on titanium implant material (2005) Biomaterials, 26, pp. 3503-3509Oliveira, C.F., Basso, F.G., Lins, E.C., Kurachi, C., Hebling, J., Bagnato, V.S., Costa, C.A.D., Increased viability of odontoblast-like cells subjected to low-level laser irradiation (2010) Laser Phys., 20, pp. 1659-1666Kossatz, S., Dalanhol, A.P., Cunha, T., Loguercio, A., Reis, A., Effect of light activation on tooth sensitivity after in-office bleaching (2011) Oper. Dent., 36, pp. 251-257Reis, A., Dalanhol, A.P., Cunha, T.S., Kossatz, S., Loguercio, A.D., Assessment of tooth sensitivity using a desensitizer before light-activated bleaching (2011) Oper. Dent., 36, pp. 12-17Lima, A.F., Ribeiro, A.P., Basso, F.G., Bagnato, V.S., Hebling, J., Marchi, G.M., De Souza Costa, C.A., Effect of low-level laser therapy on odontoblast-like cells exposed to bleaching agent (2013) Lasers Med. Sci., , (In press, DOI: 10.1007/s10103-013-1309-2)Hanks, C.T., Sun, Z.L., Fang, D.N., Edwards, C.A., Wataha, J.C., Ritchie, H.H., Butler, W.T., Cloned 3T6 cell line from CD-1 mouse fetal molar dental papillae (1998) Connect. Tissue Res., 37, pp. 233-249Sun, Z.L., Fang, D.N., Wu, X.Y., Ritchie, H.H., Begue-Kirn, C., Wataha, J.C., Hanks, C.T., Butler, W.T., Expression of dentin sialoprotein (DSP) and other molecular determinants by a new cell line from dental papillae, MDPC-23 (1998) Connect. Tissue Res., 37, pp. 251-261Chandler, N.P., The radiographic assessment of pulp size: Validity and clinical implications (1989) N. Z. Dent. 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The impact of radiation caries in the quality of life of head and neck cancer patients

Purpose: The objective of this multicentre study was to verify the relationship between the scores of quality of life (QoL) and the decayed, missing and filled teeth (DMFT) and radiation caries (RC) in patients treated with radiation therapy (RT) for head and neck cancer, and through this to determine if RC is capable of causing a significant decrease in the QoL. Methods: One hundred patients were divided into 2 groups: patients with at least 1 year of RT completion who developed RC (study group, n = 50); and patients with at least 1 year of RT completion who did not develop RC (control group, n = 50). All patients answered the Brazilian–Portuguese version of the University of Washington quality of life (UW-QoL) questionnaire, which was divided into physical and social–emotional functioning domains and evaluated the DMFT index score. Results: The mean score of QoL was 927.2 in the control group and 878.1 in the study group (P = 0.24). The mean score of DMFT was 30.5 in the study group and 20.7 in the control group (P = 0.001). The items recreation and saliva, which belong to the physical function domain, showed a statistically significant difference between the study and control groups (P = 0.031 and P = 0.047, respectively). Saliva was the item with the higher number of patient complaints in both groups. Conclusion: RC had a negative impact on the QoL of HNC patients.2829772984CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPSem informaçãoSem informação2013/18402-8; 2018/02233-6; 2018/04657-

Metabolic Profile of Supragingival Plaque Exposed to Arginine and Fluoride

Caries lesions develop when acid production from bacterial metabolism of dietary carbohydrates outweighs the various mechanisms that promote pH homeostasis, including bacterial alkali production. Therapies that provide arginine as a substrate for alkali production in supragingival oral biofilms have strong anticaries potential. The objective of this study was to investigate the metabolic profile of site-specific supragingival plaque in response to the use of arginine (Arg: 1.5% arginine, fluoride-free) or fluoride (F: 1,100 ppm F/NaF) toothpastes. Eighty-three adults of different caries status were recruited and assigned to treatment with Arg or F for 12 wk. Caries lesions were diagnosed using International Caries Detection and Assessment System II, and plaque samples were collected from caries-free and carious tooth surfaces. Taxonomic profiles were obtained by HOMINGS (Human Oral Microbe Identification using Next Generation Sequencing), and plaque metabolism was assessed by the levels of arginine catabolism via the arginine deiminase pathway (ADS), acidogenicity, and global metabolomics. Principal component analysis (PCA), partial least squares–discriminant analysis, analysis of variance, and random forest tests were used to distinguish metabolic profiles. Of the 509 active lesions diagnosed at baseline, 70 (14%) were inactive after 12 wk. Generalized linear model showed that enamel lesions were significantly more likely to become inactive compared to dentin lesions (P \u3c 0.0001), but no difference was found when treatment with Arg was compared to F (P = 0.46). Arg significantly increased plaque ADS activity (P = 0.031) and plaque pH values after incubation with glucose (P = 0.001). F reduced plaque lactate production from endogenous sources (P = 0.02). PCA revealed differences between the metabolic profiles of plaque treated with Arg or F. Arg significantly affected the concentrations of 16 metabolites, including phenethylamine, agmatine, and glucosamine-6-phosphate (P \u3c 0.05), while F affected the concentrations of 9 metabolites, including phenethylamine, N-methyl-glutamate, and agmatine (P \u3c 0.05). The anticaries mechanisms of action of arginine and fluoride are distinct. Arginine metabolism promotes biofilm pH homeostasis, whereas fluoride is thought to enhance resistance of tooth minerals to low pH and reduce acid production by supragingival oral biofilms