Tissue Reactions to Methyl- and Ethyl-2-Cyanoacrylate Adhesives

¹ Eastman Dental Center, Rochester, New York

Tissue reactions of methyl and ethyl cyanoacrylates, with and without fillers such as are used in dental adhesive application of these materials, have been compared with conventional restorative materials such as amalgam and cold-curing acrylics. Freshly mixed cyanoacrylates implanted subcutaneously in rats and in bone marrow of rabbits revealed that, although all implants were retained and clinical healing of the wound appeared normal, a persistent chronic inflammatory reaction ranging from moderate to severe at 20 days and moderate to mild after 60 days in the soft tissues was noticed histologically. Bone marrow responses ranged from moderate to mild with cyanoacrylates plus a siliceous filler and mild when combined with polymethyl methacrylate filler. Reaction to conventional materials were generally mild to moderate, diminishing in intensity with time. Supported by this and other evidence from implant and tissue contact studies, the use of cyanoacrylates externally as adhesive for surfaces such as human enamel does not appear to be contraindicated.