Dental adhesives hydrolyze in the mouth. This study investigated the water sorption (SOR), solubility (SOL) and cytotoxicity (CYTO) of experimental adhesives containing nitrogen-doped titanium dioxide nanoparticles (N_TiO<
sub>
2<
/sub>
). Specimens (n = 15/group [SOR, SOL]
n = 10/group [CYTO]) of unaltered Clearfil SE Protect (CSP), OptiBond Solo Plus (OSP), Adper Scotchbond (ASB) and experimental adhesives (OSP + 25% or 30% of N_TiO<
sub>
2<
/sub>
) were fabricated, desiccated (37��C) and tested for SOR and SOL according to ISO Specification 4049 (2009). CYTO specimens were UV-sterilized (8�J/cm<
sup>
2<
/sup>
) and monomer extracted in growth medium (1, 3 or 7�days). Human pulp cells were isolated and seeded (0.5 � 10<
sup>
4<
/sup>
) for MTT assay. SOR and SOL data was analyzed using GLM and SNK (? = 0.05) and CYTO data was analyzed with Kruskal?Wallis and SNK tests (? = 0.05). SOR and SOL values ranged from 25.80�?g/mm<
sup>
3<
/sup>
(30% N_TiO<
sub>
2<
/sub>
) to 28.01�?g/mm<
sup>
3<
/sup>
(OSP) and 23.88�?g/mm<
sup>
3<
/sup>
(30% N_TiO<
sub>
2<
/sub>
) to 25.39�?g/mm<
sup>
3<
/sup>
(25% N_TiO<
sub>
2<
/sub>
). CYTO results indicated that pulp cells exposed to experimental materials displayed comparable viabilities (p >
0.05) to those of OSP. Experimental materials displayed comparable SOR, SOL and CYTO values (p >
0.05) when compared to unaltered materials. N_TiO<
sub>
2<
/sub>
incorporation have not adversely impacted SOR, SOL and CYTO properties of unaltered adhesives.