engleski

Corrosion kinetics of the nickel-titanium archwires in prophylactic fluoridated agents

Aims: To determine: (1) amount of the released nickel (Ni2+) and titanium (Ti4+) ions ; (2) corrosion rates, (3) correlation between fluoride concentration in prophylactic agents and the release of Ni2+ and Ti4+ ions, and (4) allergenic potential which could be induced by average daily Ni2+ ion release from orthodontic nickel-titanium archwires during once-a-week application of caries prophylactic agents. Subjects and methods: NiTi wires were immersed in artificial saliva (AS). Once a week the wires were immersed in prophylactic agents (Mirafluor-k-gel, Elmex gelée, MI Paste Plus) for five minutes. The nickel and titanium ion release from wires was recorded after 3, 7, 14, 21 and 28 days of immersion in AS by inductively coupled plasma-optical emission spectroscopy. Corrosion rates and average daily nickel ion release (for upper and lower dental arch) were calculated. Pearson correlation and linear regression were used to explore influence of the pH value, total fluoride concentration and hydrofluoric acid (HF) concentration in prophylactic agents. Results: The cumulative ion release was: Mirafluor > Elmex > MI Paste. The release of Ni2+ and Ti4+ ions correlated highly to HF concentration in prophylactic agents, more than to total fluoride concentration in prophylactic agents. Conclusions: Interaction between the surface of orthodontic wires and the HF concentration in prophylactic agent determines the corrosion kinetic and ion release from archwire. Average daily release of nickel induced by adjuvant prophylactic agents does not reach allergenic potential.

corrosion; nickel; titanium

Izrađeno i financirano u sklopu projekta “Imunosne i regenerativne implikacije korozije dentalnih materijala u djece i adolescenata” Hrvatske zaklade za znanost (IP-2014-09-7500) voditelja Stjepana Špalja