Permeability of dental adhesives higher solvent and hydrophilic monomer content in a simplified adhesive’s composition and to the high acidity of one-step, self-etching adhesives. Even in multi-step adhesives, fluid diffusion can be relevant, due to the great permeability ob- served through the very hydrophilic and solvated primer component. AcKnoWLEdGEMEnts This is study was performed by Juliana Malac- arne-Zanon in partial fulfillment of requirements for her PhD degree, Piracicaba School of dentist- ry, State University of Campinas, Brazil. This study was supported by Grants from CAPES (P.I. Juliana Malacarne-Zanon), CNPq #300615/2007-8, CNPq #473164/2007-8 and FAPESP 07/54618-4 (P.I. Marcela Carrilho). rEFErEncEs 1. Van-Landuyt KL, Snauwaert J, De Munck J, Peumans M, Yoshida Y, Poitevin A, Coutinho E, Suzuki K, Lambrechts P, Van Meerbeek B. Systematic review of the chemical composition of contemporary dental adhesives. Biomater 2007;28:3757-3785. 2. Tay FR, Pashley DH, Suh BI, Carvalho RM, Itthagarun A. Single-step adhesives are permeable membranes. J Dent 2002;30:371-382. 3. Tay FR, Suh BI, Pashley DH, Prati C, Chuang SF, Li F. Fac- tors contributing to the incompatibility between simplified- step adhesives and self-cured or dual-cured composites. Part II. Single-bottle, total etch adhesive. J Adhes Dent 2003;5:91-105. 4. Abdalla AI, García-Godoy F. Clinical evaluation of self- etch adhesives in Class V non-carious lesions. Am J Dent 2006;19:289-292. 5. Burrow MF, Tyas MJ. A clinical trial comparing two all-in- one adhesive systems used to restore non-carious cervical lesions: results at one year. Aust Dent J 2008;53:235-238. 6. Chersoni S, Suppa P, Breschi L, Ferrari M, Tay FR, Pashley DH, Prati C. Water movement in the hybrid layer after dif- ferent dentin treatments. Dent Mater 2004;20:796-803. 7. Tay FR, Pashley DH, Yiu C, Cheong C, Hashimoto M, Itou K, Yoshiyama M, King NM. Nanoleakage types and potential implications: evidence from unfilled and filled adhesives with the same resin composition. Am J Dent 2004;17:182- 190. 8. Malacarne J, Carvalho RM, de Goes MF, Svizero N, Pashley DH, Tay FR, Yiu CK, Carrilho MR. Water sorption/solubility of dental adhesive resins. Dent Mater 2006;22:973-980. 438 European Journal of Dentistry 9. Carvalho RM, Pegoraro TA, Tay FR, Pegoraro LF, Silva NR, Pashley DH. Adhesive permeability affects coupling of resin cements that utilise self-etching primers to dentine. J Dent 2004;32:55-65. 10. Peumans M, Kanumilli P, De Munck J, Van Landuyt K, Lambrechts P, Van Meerbeek B. Clinical effectiveness of contemporary adhesives: a systematic review of current clinical trials. Dent Mater 2005;21:864-881. 11. De Goes MF, Giannini M, Di Hipólito V, Carrilho MR, Daronch M, Rueggeberg FA. Microtensile bond strength of adhesive systems to dentin with or without application of an inter- mediate flowable resin layer. Braz Dent J 2008;19:51-56. 12. Tay FR, Hashimoto M, Pashley DH, Peters MC, Lai SC, Yiu CK, Cheong C. Aging affects two modes of nanoleakage ex- pression in bonded dentin. J Dent Res 2003;82:537-541. 13. Suppa P, Breschi L, Ruggeri A, Mazzotti G, Prati C, Cher- soni S, Di Lenarda R, Pashley DH, Tay FR. Nanoleakage within the hybrid layer: a correlative FEISEM/TEM investi- gation. J Biomed Mater Res B Appl Biomater 2005;73:7-14. 14. Tay FR, Pashley DH. Water treeing a potential mechanism for degradation of dentin adhesives. Am J Dent 2003;16:6- 12. 15. Reis A, Loguercio AD, Azevedo CL, de Carvalho RM, da Ju- lio Singer M, Grande RH. Moisture spectrum of deminer- alized dentin for adhesive systems with different solvent bases. J Adhes Dent 2003;5:183-192. 16. Van Landuyt KL, De Munck J, Snauwaert J, Coutinho E, Poitevin A, Yoshida Y, Inoue S, Peumans M, Suzuki K, Lambrechts P, Van Meerbeek B. Monomer-solvent phase separation in one-step self-etch adhesives. J Dent Res 2005;84:183-188. 17. Ye Q, Wang Y, Spencer P. Nanophase separation of poly- mers exposed to simulated bonding conditions. J Biomed Mater Res B Appl Biomater 2009;88:339-348. 18. Van Meerbeek B. The "myth" of nanoleakage. J Adhes Dent 2007;9:491-492. 19. Ferracane JL. Hygroscopic and hydrolytic effects in dental polymer networks. Dent Mater 2006;22:211-222. 20. Malacarne-Zanon J. Effect of solvent type and solvent con- centration on the permeability of adhesive systems (thesis). Piracicaba: UNICAMP/FOP; 2009. 21. Kanca J, 3rd. Effect of resin primer solvents and surface wetness on resin composite bond strength to dentin. Am J Dent 2002;5:213-215. 22. Soles CL, Yee AF. A discussion of the molecular mecha- nisms of moisture transport in epoxy resins. J Polym Sci 2000;38:792-802.