Biocompatibility of Resin Based Cements - Primary Skin Irritation Test

Method: The back of the animals (New Zealand White rabbits, n=9) were clipped free of fur at least 24 hours before application of the samples and skin was schematically divided into four zones. The test material was applied on only two zones. Remaining two areas were used as positive (lactic acid 98%) and negative controls (hypoallergenic adhesive patch). After four hour exposure the samples were removed, and an hour later macro pathological examination was made for signs of skin irritation (erythema, edema). After 24, 48 and 72 hours from sample application, the test areas were examined for skin reactions in accordance with the FHSA-recommended Draize scoring criteria.

Result: The primary irritation index (P.I.I.) of the each resin based cements  was calculated, based on the sum of the scored reactions divided  by 18 ( three scoring intervals, multiplied by two samples, multiplied by three rabbits).The primary irritation index for  each resin based cement was 0 and was not statistically different in comparison to the negative control.

Conclusion: Under the conditions of this test, the resin based cements  would not be considered as primary skin irritant.