Experimental and clinical study of the concentrations of chemical elements in oral fluid from prostheses and implants

BACKGROUND: Electrochemical reactions can occur in the mouth of patients with prostheses made of metal alloys. The phenomena of galvanism reflect the hidden process of corrosion of structural alloys in oral fluid, which makes it necessary to analyze the chemical contents of prostheses under clinical conditions in patients with implants and experimental conditions.

AIM: Comparative analysis of the trace element content in the oral fluid from prostheses in implants in the clinic and an experiment.

MATERIALS AND METHODS: National Research Technological University “MISIS” analyzed artificial saliva after prostheses were in contact with grade 4 and grade 5 implants for 3 months. Titanium, cobalt, chromium, aluminum, vanadium, molybdenum, tungsten, manganese, nickel, and iron were determined by spectrometry. The same chemical elements were analyzed using an identical spectrometric method in 32 patients with fixed dentures on implants.

RESULTS: Under the experimental conditions, nine trace elements were found in the container around one grade 4 implant with a crown, including titanium (0.4 µg/l), cobalt (3.8 µg/l), chromium (0.5 µg/l), aluminum (2.6 µg/l), vanadium (<0.6 µg/l), molybdenum (1.5 µg/l), tungsten (3.0 µg/l), manganese (0.9 µg/l), nickel (0.5 µg/l), and iron (<0.6 µg/l). The grade 5 implant was characterized by a greater degree of diffusion of aluminum, nickel, and manganese into artificial saliva. Mass spectrometry of the oral fluid in patients with dental implants revealed more trace elements than experimental data. The difference in the concentration of microelements from the prostheses under clinical conditions and in the experiment ranged from 0 to 128 times the minimum.

CONCLUSION: Fixing experimental prostheses on implants for 3 months in artificial saliva was accompanied by the diffusion of microelements from the prostheses and implants into the environment, particularly cobalt, aluminum, and vanadium. Prostheses on implants with a lower titanium content are characterized by a greater degree of diffusion of aluminum, cobalt, nickel, and manganese. More significant diffusion of microelements occurred from the prostheses into the saliva under clinical conditions, according to the spectrometric data.