This study demonstrates that titanium, which is well known for its corrosion resistance, does not withstand certain acidic fluoride prophylactic agents. Neutral sodium fluoride solutions do not affect titanium surfaces. If fluoride preparations are to be used in patients who have titanium implants or restorations, the effect of the agent on titanium must be examined to prevent damage to the restorations. Schlagwörter: fluoride, prophylactic agents, surface corrosion, titanium