Permeability, Roughness And Topography Of Enamel After Bleaching: Tracking Channels Of Penetration With Silver Nitrate

Aim: This study evaluated the surface roughness, topography and permeability of bovine enamel by profilometry and scanning electron microscopy (SEM) with and without silver nitrate solution, after exposure to different bleaching agents. Methods: Fifty-two enamel samples were randomly divided into four groups (n=13): CP16% -16% carbamide peroxide - Whiteness Perfect; HP6% - 6% hydrogen peroxide - White Class; HP35% - 35% hydrogen peroxide Whiteness HP Maxx; and Control - not bleached and kept in artificial saliva. For roughness analysis, average surface roughness (Ra) and flatness coefficient (Rku) parameters were used. The topography and permeability were examined by SEM. For permeability evaluation, the samples were immersed in a 50% silver nitrate solution and analyzed using a backscattered electron and secondary electron mode. Results: For the roughness (Ra) evaluation, Kruskal-Wallis and Wilcoxon Signed Ranks Test were used, showing an increase on the surface roughness in all bleached groups. The Rku parameter suggested changes on enamel integrity. The SEM micrographs indicated changes on enamel topography and different levels of silver nitrate penetration in the samples of the bleached groups. In the overall analysis, the bleaching agents promoted surface changes and higher silver nitrate penetration when compared to the control group. Conclusions: It may be concluded that different bleaching agents might alter the topography and roughness of enamel surface. Moreover, the higher infiltration of silver nitrate suggests an easier penetration path for the oxygen molecules into the dentin substrate.10116Nathoo, S.A., The chemistry and mechanisms of extrinsic and intrinsic discoloration (1997) J Am Dent Assoc, 128 (SUPPL.), pp. 6S-10SMcEvoy, S.A., Chemical agents for removing intrinsic stains from vital teeth. II. Current techniques and their clinical application (1989) Quintessence Int, 20, pp. 379-384Ben-Amar, A., Liberman, R., Gorfil, C., Bernstein, Y., Effect of mouthguard bleaching on enamel surface (1995) Am J Dent, 8, pp. 29-32Lynch, E., Sheerin, A., Samarawickrama, D.Y., Atherton, M.A., Claxson, A.W., Hawkes, J., Molecular mechanisms of the bleaching actions associated with commercially-available whitening oral health care products (1995) J Ir Dent Assoc, 41, pp. 94-102Bowles, W.H., Ugwuneri, Z., Pulp chamber penetration by hydrogen peroxide following vital bleaching procedures (1987) J Endod, 13, pp. 375-377Sun, G., The role of lasers in cosmetic dentistry (2000) Dent Clin North Am, 44, pp. 831-850Hegedus, C., Bistey, T., Flora-Nagy, E., Keszthelyi, G., Jenei, A., An atomic force microscopy study on the effect of bleaching agents on enamel surface (1999) J Dent, 27, pp. 509-515Park, H.J., Kwon, T.Y., Nam, S.H., Kim, H.J., Kim, K.H., Kim, Y.J., Changes in bovine enamel after treatment with a 30% hydrogen peroxide bleaching agent (2004) Dent Mater J, 23, pp. 517-521Iwamoto, N., Shimada, Y., Tagami, J., Penetration of silver nitrate into bleached enamel, dentin, and cementum (2007) Quintessence Int, 38, pp. e183-e188Cavalli, V., Arrais, C.A., Giannini, M., Ambrosano, G.M., High-concentrated carbamide peroxide bleaching agents effects on enamel surface (2004) J Oral Rehabil, 31, pp. 155-159Hosoya, N., Honda, K., Iino, F., Arai, T., Changes in enamel surface roughness and adhesion of Streptococcus mutans to enamel after vital bleaching (2003) J Dent, 31, pp. 543-548Josey, 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. 244-250Lee, C.Q., Cobb, C.M., Zargartalebi, F., Hu, N., Effect of bleaching on microhardness, morphology, and color of enamel (1995) Gen Dent, 43, pp. 158-160McGuckin, R.S., Babin, J.F., Meyer, B.J., Alterations in human enamel surface morphology following vital bleaching (1992) J Prosthet Dent, 68, pp. 754-760Pinto, C.F., Oliveira, R., Cavalli, V., Giannini, M., Peroxide bleaching agent effects on enamel surface microhardness, roughness and morphology (2004) Braz Oral Res, 18, pp. 306-311Shannon, H., Spencer, P., Gross, K., Tira, D., Characterization of enamel exposed to 10% carbamide peroxide bleaching agents (1993) Quintessence Int, 24, pp. 39-44Zalkind, M., Arwaz, J.R., Goldman, A., Rotstein, I., Surface morphology changes in human enamel, dentin and cementum following bleaching: a scanning electron microscopy study (1996) Endod Dent Traumatol, 12, pp. 82-88Ernst, C.P., Marroquin, B.B., Willershausen-Zonnchen, B., Effects of hydrogen peroxide-containing bleaching agents on the morphology of human enamel (1996) Quintessence Int, 27, pp. 53-56Gultz, J., Kaim, J., Scherer, W., Gupta, H., Two in-office bleaching systems: a scanning electron microscope study (1999) Compend Contin Educ Dent, 20, pp. 965-968. , 70quiz 72Haywood, V.B., Heymann, H.O., Nightguard vital bleaching: how safe is it? (1991) Quintessence Int, 22, pp. 515-523Haywood, V.B., Leech, T., Heymann, H.O., Crumpler, D., Bruggers, K., Nightguard vital bleaching: effects on enamel surface texture and diffusion (1990) Quintessence Int, 21, pp. 801-804Oltu, U., Gurgan, S., Effects of three concentrations of carbamide peroxide on the structure of enamel (2000) J Oral Rehabil, 27, pp. 332-340Spalding, M., Taveira, L.A., de Assis, G.F., Scanning electron microscopy study of dental enamel surface exposed to 35% hydrogen peroxide: alone, with saliva, and with 10% carbamide peroxide (2003) J Esthet Restor Dent, 15, pp. 154-165Sulieman, M., Addy, M., Macdonald, E., Rees, J.S., A safety study in vitro for the effects of an in-office bleaching system on the integrity of enamel and dentine (2004) J Dent, 32, pp. 581-590Tong, L.S., Pang, M.K., Mok, N.Y., King, N.M., Wei, S.H., The effects of etching, micro-abrasion, and bleaching on surface enamel (1993) J Dent Res, 72, pp. 67-71Bagheri, R., Tyas, M.J., Burrow, M.F., Subsurface degradation of resin-based composites (2007) Dent Mater, 23, pp. 944-951Reis, A., Grande, R.H., Oliveira, G.M., Lopes, G.C., Loguercio, A.D., A 2-year evaluation of moisture on microtensile bond strength and nanoleakage (2007) Dent Mater, 23, pp. 862-870Ritter, A.V., Ghaname, E., Leonard, R.H., The influence of dental unit waterline cleaners on composite-to-dentin bond strengths (2007) J Am Dent Assoc, 138, pp. 985-991. , quiz 1022-3Sano, H., Shono, T., Takatsu, T., Hosoda, H., Microporous dentin zone beneath resin-impregnated layer (1994) Oper Dent, 19, pp. 59-64Nanci, A., (2007) Ten Cate's oral histology: development, structure, and function, , 7th ed. Saint Louis: Mosby-ElsevierCeliberti, P., Pazera, P., Lussi, A., The impact of ozone treatment on enamel physical properties (2006) Am J Dent, 19, pp. 67-72Chen, J.H., Xu, J.W., Shing, C.X., Decomposition rate of hydrogen peroxide bleaching agents under various chemical and physical conditions (1993) J Prosthet Dent, 69, pp. 46-48Reyto, R., Laser tooth whitening (1998) Dent Clin North Am., 42, pp. 755-762. , xiBitter, N.C., Sanders, J.L., The effects of four bleaching agents on the enamel surface: a scanning electron microscopic study (1993) Quintessence Int, 24, pp. 817-824Leonard Jr., R.H., Austin, S.M., Haywood, V.B., Bentley, C.D., Change in pH of plaque and 10% carbamide peroxide solution during nightguard vital bleaching treatment (1994) Quintessence Int, 25, pp. 819-823Leonard Jr., R.H., Bentley, C.D., Haywood, V.B., Salivary pH changes during 10% carbamide peroxide bleaching (1994) Quintessence Int, 25, pp. 547-550Li, Y., Biological properties of peroxide-containing tooth whiteners (1996) Food Chem Toxicol, 34, pp. 887-904Price, R.B., Sedarous, M., Hiltz, G.S., The pH of tooth-whitening products (2000) J Can Dent Assoc, 66, pp. 421-426Yeh, S.T., Su, Y., Lu, Y.C., Lee, S.Y., Surface changes and acid dissolution of enamel after carbamide peroxide bleach treatment (2005) Oper Dent, 30, pp. 507-515Justino, L.M., Tames, D.R., Demarco, F.F., In situ and in vitro effects of bleaching with carbamide peroxide on human enamel (2004) Oper Dent, 29, pp. 219-22

Long-term Effect Of Chlorhexidine On The Dentin Microtensile Bond Strength Of Conventional And Self-adhesive Resin Cements: A Two-year In Vitro Study

Since degradation of the adhesive interface plays an important role on dental restoration failure overtime, bonding protocols containing metalloproteinase synthetic inhibitors could be a valuable approach to preserve the bond strength of indirect restorations. A flat dentin surface was created on 40 recently extracted non-carious human third molars (n=10). Resin-composite blocks were randomly cemented using two resin cements: a self-adhesive and a conventional. A buffer-free 2% chlorhexidine digluconate solution was used as dentin pretreatment on experimental groups. Microtensile bond strength test was performed immediately and after specimen aging for two-years in artificial saliva. Fracture patterns were determined by SEM. Even after significant reduction in bonding effectiveness with aging, dentin bond strength values of the conventional resin cement remained higher compared to those of the self-adhesive resin cement especially when chlorhexidine pretreatment was performed. No statistical differences were observed between immediate and aged specimens luted with the self-adhesive resin cement. Chlorhexidine was effective to preserve dentin bond strength of indirect restorations when the conventional resin cement was used. © 2014 Elsevier Ltd.50228234Furukawa, K., Inai, N., Tagami, J., The effects of luting resin bond to dentin on the strength of dentin supported by indirect resin composite (2002) Dental Materials, 18 (2), pp. 136-142. , DOI 10.1016/S0109-5641(01)00032-X, PII S010956410100032XPiwowarczyk, A., Bender, R., Ottl, P., Lauer, H.-C., Long-term bond between dual-polymerizing cementing agents and human hard dental tissue (2007) Dental Materials, 23 (2), pp. 211-217. , DOI 10.1016/j.dental.2006.01.012, PII S0109564106000170Yang, B., Ludwig, K., Adelung, R., Kern, M., Micro-tensile bond strength of three luting resins to human regional dentin (2006) Dental Materials, 22 (1), pp. 45-56. , DOI 10.1016/j.dental.2005.02.009, PII S0109564105001272Gerth, H.U.V., Dammaschke, T., Zuchner, H., Schafer, E., Chemical analysis and bonding reaction of RelyX Unicem and Bifix composites-A comparative study (2006) Dental Materials, 22 (10), pp. 934-941. , DOI 10.1016/j.dental.2005.10.004, PII S0109564105003088Nakamura, T., Wakabayashi, K., Kinuta, S., Nishida, H., Miyamae, M., Yatani, H., Mechanical properties of new self-adhesive resin-based cement (2010) J Prosthodont Res, 54 (2), pp. 59-64Radovic, I., Monticelli, F., Goracci, C., Vulicevic, Z.R., Ferrari, M., Self-adhesive resin cements: A literature review (2008) J Adhes Dent, 10 (4), pp. 251-258Hashimoto, M., Ohno, H., Sano, H., Kaga, M., Oguchi, H., In vitro degradation of resin-dentin bonds analyzed by microtensile bond test, scanning and transmission electron microscopy (2003) Biomaterials, 24 (21), pp. 3795-3803. , DOI 10.1016/S0142-9612(03)00262-XDe Munck, J., Van Landuyt, K., Peumans, M., Poitevin, A., Lambrechts, P., Braem, M., Van Meerbeek, B., A critical review of the durability of adhesion to tooth tissue: Methods and results (2005) Journal of Dental Research, 84 (2), pp. 118-132. , DOI 10.1177/154405910508400204Monticelli, F., Osorio, R., Mazzitelli, C., Ferrari, M., Toledano, M., Limited decalcification/diffusion of self-adhesive cements into dentin (2008) J Dent Res, 87 (10), pp. 974-979Wang, Y., Spencer, P., Hybridization efficiency of the adhesive/dentin interface with wet bonding (2003) Journal of Dental Research, 82 (2), pp. 141-145Spencer, P., Wang, Y., Katz, J.L., Identification of collagen encapsulation at the dentin/adhesive interface (2004) Journal of Adhesive Dentistry, 6 (2), pp. 91-95Pashley, D.H., Tay, F.R., Yiu, C., Hashimoto, M., Breschi, L., Carvalho, R.M., Ito, S., Collagen degradation by host-derived enzymes during aging (2004) Journal of Dental Research, 83 (3), pp. 216-221Garcia-Godoy, F., Tay, F.R., Pashley, D.H., Feilzer, A., Tjaderhane, L., Pashley, E.L., Degradation of resin-bonded human dentin after 3 years of storage (2007) Am J Dent, 20 (2), pp. 109-113Carrilho, M.R., Geraldeli, S., Tay, F., De Goes, M.F., Carvalho, R.M., Tjaderhane, L., Reis, A.F., Pashley, D., In vivo preservation of the hybrid layer by chlorhexidine (2007) J Dent Res, 86 (6), pp. 529-533Martin-De Las Heras, S., Valenzuela, A., Overall, C.M., The matrix metalloproteinase gelatinase A in human dentine (2000) Archives of Oral Biology, 45 (9), pp. 757-765. , DOI 10.1016/S0003-9969(00)00052-2, PII S0003996900000522Sulkala, M., Larmas, M., Sorsa, T., Salo, T., Tjaderhane, L., The localization of matrix metalloproteinase-20 (MMP-20, enamelysin) in mature human teeth (2002) J Dent Res, 81 (9), pp. 603-607Mazzoni, A., Pashley, D.H., Nishitani, Y., Breschi, L., Mannello, F., Tjaderhane, L., Toledano, M., Tay, F.R., Reactivation of inactivated endogenous proteolytic activities in phosphoric acid-etched dentine by etch-and-rinse adhesives (2006) Biomaterials, 27 (25), pp. 4470-4476. , DOI 10.1016/j.biomaterials.2006.01.040, PII S0142961206001256Mazzoni, A., Papa, V., Nato, F., Carrilho, M., Tjaderhane, L., Ruggeri, Jr.A., Gobbi, P., Breschi, L., Immunohistochemical and biochemical assay of MMP-3 in human dentine (2011) J Dent, 39 (3), pp. 231-237Lehmann, N., Debret, R., Romeas, A., Magloire, H., Degrange, M., Bleicher, F., Sommer, P., Seux, D., Self-etching increases matrix metalloproteinase expression in the dentin-pulp complex (2009) J Dent Res, 88 (1), pp. 77-82Nishitani, Y., Yoshiyama, M., Wadgaonkar, B., Breschi, L., Mannello, F., Mazzoni, A., Carvalho, R.M., Pashley, D.H., Activation of gelatinolytic/collagenolytic activity in dentin by self-etching adhesives (2006) European Journal of Oral Sciences, 114 (2), pp. 160-166. , DOI 10.1111/j.1600-0722.2006.00342.xLindblad, R.M., Lassila, L.V., Salo, V., Vallittu, P.K., Tjaderhane, L., One year effect of chlorhexidine on bonding of fibre-reinforced composite root canal post to dentine (2012) J Dent, 40 (9), pp. 718-722Tay, F.R., Pashley, D.H., Loushine, R.J., Weller, R.N., Monticelli, F., Osorio, R., Self-Etching Adhesives Increase Collagenolytic Activity in Radicular Dentin (2006) Journal of Endodontics, 32 (9), pp. 862-868. , DOI 10.1016/j.joen.2006.04.005, PII S009923990600416XOliveira, S.S.A., Marshall, S.J., Habelitz, S., Gansky, S.A., Wilson, R.S., Marshall Jr., G.W., The effect of a self-etching primer on the continuous demineralization of dentin (2004) European Journal of Oral Sciences, 112 (4), pp. 376-383. , DOI 10.1111/j.1600-0722.2004.00142.xFardal, O., Turnbull, R.S., A review of the literature on use of chlorhexidine in dentistry (1986) J Am Dent Assoc, 112 (6), pp. 863-869Gendron, R., Grenier, D., Sorsa, T., Mayrand, D., Inhibition of the activities of matrix metalloproteinases 2, 8, and 9 by chlorhexidine (1999) Clinical and Diagnostic Laboratory Immunology, 6 (3), pp. 437-439Hebling, J., Pashley, D.H., Tjaderhane, L., Tay, F.R., Chlorhexidine arrests subclinical degradation of dentin hybrid layers in vivo (2005) J Dent Res, 84 (8), pp. 741-746Carrilho, M.R., Carvalho, R.M., De Goes, M.F., Di Hipolito, V., Geraldeli, S., Tay, F.R., Pashley, D.H., Tjäderhane, L., Chlorhexidine preserves dentin bond in vitro (2007) J Dent Res, 86 (1), pp. 90-94Hashimoto, M., Ohno, H., Kaga, M., Endo, K., Sano, H., Oguchi, H., Resin-tooth adhesive interfaces after long-term function (2001) American Journal of Dentistry, 14 (4), pp. 211-215Hashimoto, M., Ohno, H., Kaga, M., Endo, K., Sano, H., Oguchi, H., In vivo degradation of resin-dentin bonds in humans over 1 to 3 years (2000) Journal of Dental Research, 79 (6), pp. 1385-1391Goracci, C., Cury, A.H., Cantoro, A., Papacchini, F., Tay, F.R., Ferrari, M., Microtensile bond strength and interfacial properties of self-etching and self-adhesive resin cements used to lute composite onlays under different seating forces (2006) Journal of Adhesive Dentistry, 8 (5), pp. 327-335Shono, Y., Ogawa, T., Terashita, M., Carvalho, R.M., Pashley, E.L., Pashley, D.H., Regional measurement of resin-dentin bonding as an array (1999) Journal of Dental Research, 78 (2), pp. 699-705El Zohairy, A.A., De Gee, A.J., Mohsen, M.M., Feilzer, A.J., Effect of conditioning time of self-etching primers on dentin bond strength of three adhesive resin cements (2005) Dental Materials, 21 (2), pp. 83-93. , DOI 10.1016/j.dental.2003.12.002, PII S0109564104000363Al-Assaf, K., Chakmakchi, M., Palaghias, G., Karanika-Kouma, A., Eliades, G., Interfacial characteristics of adhesive luting resins and composites with dentine (2007) Dental Materials, 23 (7), pp. 829-839. , DOI 10.1016/j.dental.2006.06.023, PII S0109564106001837Tay, F.R., Smales, R.J., Ngo, H., Wei, S.H.Y., Pashley, D.H., Effect of different conditioning protocols on adhesion of a GIC to dentin (2001) Journal of Adhesive Dentistry, 3 (2), pp. 153-167Hikita, K., Van Meerbeek, B., De Munck, J., Ikeda, T., Van Landuyt, K., Maida, T., Lambrechts, P., Peumans, M., Bonding effectiveness of adhesive luting agents to enamel and dentin (2007) Dental Materials, 23 (1), pp. 71-80. , DOI 10.1016/j.dental.2005.12.002, PII S0109564105003611Pashley, D.H., Carvalho, R.M., Sano, H., Nakajima, M., Yoshiyama, M., Shono, Y., Fernandes, C.A., Tay, F., The microtensile bond test: A review (1999) J Adhes Dent, 1 (4), pp. 299-309Salz, U., Bock, T., Testing adhesion of direct restoratives to dental hard tissue - A review (2010) J Adhes Dent, 12 (5), pp. 343-371Breschi, L., Perdigao, J., Gobbi, P., Mazzotti, G., Falconi, M., Lopes, M., Immunocytochemical identification of Type I collagen in acid-etched dentin (2003) Journal of Biomedical Materials Research - Part A, 66 (4), pp. 764-769Mazzitelli, C., Monticelli, F., Toledano, M., Ferrari, M., Osorio, R., Dentin treatment effects on the bonding performance of self-adhesive resin cements (2010) Eur J Oral Sci, 118 (1), pp. 80-86Tjaderhane, L., Larjava, H., Sorsa, T., Uitto, V.-J., Larmas, M., Salo, T., The activation and function of host matrix metalloproteinases in dentin matrix breakdown in caries lesions (1998) Journal of Dental Research, 77 (8), pp. 1622-1629Yiu, C.K.Y., King, N.M., Pashley, D.H., Suh, B.I., Carvalho, R.M., Carrilho, M.R.O., Tay, F.R., Effect of resin hydrophilicity and water storage on resin strength (2004) Biomaterials, 25 (26), pp. 5789-5796. , DOI 10.1016/j.biomaterials.2004.01.026, PII S0142961204000626Tay, F.R., Hashimoto, M., Pashley, D.H., Peters, M.C., Lai, S.C.N., Yiu, C.K.Y., Cheong, C., Aging affects two modes of nanoleakage expression in bonded dentin (2003) Journal of Dental Research, 82 (7), pp. 537-541Shafiei, F., Memarpour, M., Effect of chlorhexidine application on long-term shear bond strength of resin cements to dentin (2010) J Prosthodont Res, 54 (4), pp. 153-158Lindblad, R.M., Lassila, L.V., Salo, V., Vallittu, P.K., Tjaderhane, L., Effect of chlorhexidine on initial adhesion of fiber-reinforced post to root canal (2010) J Dent, 38 (10), pp. 796-801Stape, T., Menezes, M., Barreto, B., Aguiar, F., Martins, L., Quagliatto, P., Influence of matrix metalloproteinase synthetic inhibitors on dentin microtensile bond strength of resin cements (2012) Oper Dent, 37 (4), pp. 386-396Kim, J., Uchiyama, T., Carrilho, M., Agee, K.A., Mazzoni, A., Breschi, L., Carvalho, R.M., Pashley, D.H., Chlorhexidine binding to mineralized versus demineralized dentin powder (2010) Dent Mater, 26 (8), pp. 771-778Hiraishi, N., Yiu, C.K., King, N.M., Tay, F.R., Effect of 2% chlorhexidine on dentin microtensile bond strengths and nanoleakage of luting cements (2009) J Dent, 37 (6), pp. 440-448Di Hipolito, V., Rodrigues, F.P., Piveta, F.B., Azevedo Lda, C., Bruschi Alonso, R.C., Silikas, N., Carvalho, R.M., Perlatti D'Alpino, P.H., Effectiveness of self-adhesive luting cements in bonding to chlorhexidine-treated dentin (2012) Dent Mater, 28 (5), pp. 495-501Freire, L.G., Carvalho, C.N., Ferrari, P.H., Siqueira, E.L., Gavini, Influence of dentin on pH of 2% chlorhexidine gel and calcium hydroxide alone or in scombination (2010) Dent Traumatol, 26 (3), pp. 276-28