The aim of this study was to assess the fluoride (F) release potential of Fcontaining adhesives Transbond Plus (TB+), Light Bond (LBF), and Geristore-Tenure (GS), and a control adhesive without F content, Transbond XT (TBXT), in relation to microhardness (µH) and degree of conversion (DC). Ten specimens of each adhesive system were illuminated at 1100 mW/cm2 for 10 and 20 sec, totalling 80 samples. Fourier transform infrared spectroscopy was used for the assessment of DC. µH was assessed before and after four- weeks of immersion in artificial saliva (pH 4.8) at 37°C. The amount of F release was monitored by a F ion-selective electrode. F release was related to adhesive system type and curing time (pTB+20>GS10>GS20>LBF10>LBF20. The decrease of µH after four weeks of immersion in artificial saliva is related to increased release of F (r=0.651 ; p<0.001). TB+ had significantly superior white spot lesions preventive potential due to twice higher F ions release, but its high µH changes raise concerns of bond strength properties. The tested materials showed low F recharge potential.