PerioChip has been tested for cytotoxicity in vitro, for mutagenicity using the mouse micronucleus assay, for oral mucosal irritation potential using a Hamster cheek pouch model and for subchronic oral toxicity in a 30 day ingestion study in rats.
Cytotoxicity
In Chinese Hamster lung cells (V79), PerioChip showed marked in vitro cytotoxicity. The cytotoxicity of the PerioChip was considerably less than that of chlorhexidine digluconate alone and was reduced by the addition of a rat liver-derived, metabolic activation system. Thus, the cytotoxicity of the active, chlorhexidine digluconate, is reduced when incorporated into the PerioChip
Mutagenicity
The potential of PerioChip to induce chromosomal or other damage was assessed in vivo by evaluating the formation of micronuclei in immature bone marrow erythrocytes in mice. No significant chromosomal or other damage was observed with the PerioChip for any test dose up to and including 1240 mg/kg chlorhexidine digluconate compared to the vehicle control.
Oral mucosal irritation
The potential of PerioChip to induce irritation was evaluated through surgical insertion into Hamster cheek pouches for either 7 or 14 days. Mucosal irritation was observed after removal of the PerioChips and, through comparison with sites treated with placebo periodontal inserts, was considered to be caused by the chlorhexidine digluconate. There were few instances of significant differences in erythema and oedema. The effects were transitory and the animals had recovered seven days after periodontal insert removal, indicating either that the initial localised effects were biologically insignificant or that the healing process was rapid.
Oral toxicity
Daily dosing for 30 days with up to 37.5 mg/kg of PerioChip powder containing chlorhexidine digluconate caused no adverse reactions in rats.
Reproductive toxicity
In reproduction and fertility studies with chlorhexidine digluconate, no evidence of impaired fertility was observed in rats at doses up to 100 mg/kg/day, and no evidence of harm to the fetus was observed in rats and rabbits at doses up to 300 mg/kg/day and 40 mg/kg/day, respectively.
Animal studies using rats have shown no evidence of toxic effects to suckling pups when chlorhexidine was administered to dams. The chlorhexidine doses used were greater than 100 times the amount administered to a person treated with twelve PerioChips.