Galvanism, oral

Oral corrosion of metallic restorations does not, per se, generally result in serious damage to the structure. Corrosion can result, however, in various local and systemic effects, notably the hypersensitivity and allergic reactions reported by many workers. Galvanic cells created by mixed metal couples can delay fracture healing and induce oral lesions and cancer. 

Axell T, Nilner K, Nilsson B Clinical evaluation of patients referred with symptoms related to oral galvanism. Swed Dent J 7 169-178,1983 Axtell CD, Cox C, Myers GJ, et al Association between methylmercury exposure from fish consumption and child development at five and a half years of age in the Seychelles Child Development Study an evaluation of nonlinear relationships. Environ Res 84 71-80, 2000... 

Johansson B, Stenman E, Bergman M Medical study of patients referred for investigation regarding so-called oral galvanism. Scandinavian Journal of Dental Research 92 469—475,1984... 

Jontell M, ffaraldson T, Persson L-O, et al An oral and psychosocial examination of patients with presumed oral galvanism. Swed Dent J 9 175-185, 1985 Li AM, Chan MH, Leung TF, et al Mercury intoxication presenting with tics. Arch Dis Child 83 174-175, 2000... 

Ion release from metallic prostheses and implants is the main origin of any unwanted primary or secondary reaction (Black 1988 Hildebrand and Hornez 1998), except for the electro-galvanic phenomena occurring in the oral cavity due to the presence of different dental alloys. In this case, the primary factor may be an electrochemically induced galvano-electric current used by the saliva as a favorable saline electrolyte (Bundy 1994 Hornez etal. 2000). 

Toxicology LD50 (oral, rat) 490 mg/kg, (skin, rabbit) 450 mg/kg LC50 (inh., rat, 4 h) 0.68 mg/l toxic by inh., ing., skin contact corrosive to eyes, skin, respiratory system severe irritant causes bums ing. may cause death absorbed thm skin may cause malaise, discomfort, injury, death target organs eyes, skin, respiratory system TSCA listed Precaution Combustible liq. incompat. with acids, oxidizers slowly corrodes copper, aluminum, zinc and galvanized surfaces reaction with peroxides may cause violent decomp., possible explosion... 

In vivo electrochemical testing is possible in humans (in the oral cavity) under restricted conditions [77,78]. Open circuit potentials and galvanic currents between dissimilar metals have been measured. Linear polarization and AC impedance tests have been conducted. The paramount concern for these measurements is obtaining accurate data under conditions that present no hazard to the human subjects. 

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