since DCC did not influence immediate bond strength to radicular dentin when applied with ethanol. Additional samples have been yet prepared and stored in artificial saliva to test the efficacy of DCC in bond strength maintenance after 6 and 12 months of storage. Aim. To investigate in a comparative clinical trial, the 12-weeks effectiveness of Vertise Flow TM (VF), self-adhering resin composite, as desensitizing agent. Methods. The study was designed as a split-mouth randomized clinical trial. The protocol and informed consent forms were approved by the ethics committee at the University of Sassari (n° 1000/CE). VF was compared to: Universal Dentine Sealant (UDS), Clearfil Protect Bond (CPB), Flor-Opal ® Varnish (FOV). Inclusion criteria: 1) two or three teeth hypersensitive to the stimulation, 2) abrasion, erosion or recession with the exposure of the cervical dentine. A total of 116 teeth were included in the study. Teeth were randomly assigned to four groups for the treatment with the four desensitising agents. The pain experience was generated by a cold stimulus directly to sensitive tooth surface and assessed using the Visual Analogue Scale (VAS). The response was recorded before the application of the materials (PRE-1), immediately after (POST-1), at 1 week (POST-2), 4 weeks (POST-3) and 12 week controls (POST-4). Statistical differences in VAS were performed using the Kruskal–Wallis analysis at the different time-points (P<0.05), adjusting statistical significances for multiple comparisons (Bonferroni correction). Results. Different responses could be observed in the post-treatment controls as a consequence of the material composition and interaction capacity in den-tin under oral environment. VF showed the ability to significantly reduce the sensitivity immediately after the application, however lowering its efficiency within the 12-week post-treatments. The acidic monomer in VF (GPDM) might raise the concentration of Ca and P from the dentin to a point where it exceeded the product's solubility constants, thus allowing for the subsequent precipitation of CaP complexes with micromechanical reduction of the tubular orifices, that can explain the significant decrease of dentine hypersensitivity (DH) in POST-1. It is likely, however, that the chemical components of the composite mass absorb water in an aqueous environment, producing hydrolytic processes that might be responsible for the deterioration of the physico-mechanical properties of the resin cover within the 12-week controls. UDS revealed Ca, Cl, and Si as the highest ions in the resin matrix, also containing Al ion peaks. In comparison to VF, UDS produced a slowly but continue decrease of the VAS showing the higher most stable desensitizing effect at POST-4. Results may be related to the different composition and filler treatment in UDS in respect to VF, leading to a filler polymer bond probably less attackable by water degradation under oral exposure. CPB showed a significant decrease of the VAS in post-1 that remained stable within the Results. Statistical analysis showed a significant difference in bond strength between Group 1 and Group 2 (p=0,0001)and between Group 3 and Group 4(p=0,001). Hydroxyapatite application significantly helps to prevent bond strength decrease overtime (p=0.0001).EDAX analysis showed that TeethMate created a Calcium-Phosphate precipitation over dentinal tubules. Conclusion. Within the limitations of an in vitro study we can affirm that the creation of calcium phosphate precipitation over dentinal walls could improve and stabilize bond strength of fiber post luted with 10 MDP-containing adhesive systems.