Morphological Reactions of Wistar Rat Tissues Exposed to Acetal Resin Implants

Morphological changes developed in rat bucal mucosa, parotid glands, and lymphoid nodes following 6 weeks exposure to dental acetal resin implants were compared to metal/titanium, acrylic implants, and sham-operated rats. Morphological evaluation of bucal mucosa of rats exposed to acetal resin showed an increased accumulation of lymphoid and macrophage-like cells compared to sham-operated rats. Eosinophils were found in bucal mucosa and in parotid glands of rats exposed to acetal resin, although this change did not differ significantly from sham-operated rats. Morphological findings with respect to granular reaction and proliferation were similar in acetal resin exposed and sham-operated rats. Acetal resin implants may induce inflammatory and potentially allergic reactions at the site of implantation.