RESUMO
Objective: The present study was conducted to evaluate the effect of denervation on the filiform and the taste budbearing fungiform lingual papillae in adult rat
Methods: Sixteen adult albino rats were subjected to unilateral combined neurectomy of the chorda tympanilingual nerve. Differences between the intact and the denervated sides of the tongue were observed at 4 weeks [experimental group I ] and 12 weeks [experimental group ll] post-sectioning. Tongue specimens of both experimental groups were subjected to light microscopic study by Haematoxylirt and eosin [H and E] stain and immunohistochemical study using neuron specificenolase antibody. Scanning electron microscopic examination was also done
Results: Several histological and morphological alterations were demonstrated in papillae 0f the denervated side which were much influenced by the longer duration ofa'ertervation. Early postneurectomy [experimental group I], the fungiform papillae were the most affected. They appeared atrophied with sunken taste pores. Taste buds appeared disorganized with pyknotic nuclei and were weakly stained for neuron speci ICenolase. After 12 weeks postneurectomy [experimental group II], the fungiform papillae revealed a striking zliformlike appearance with absent taste buds on their summits. The filiform papillae exhibited disturbed orientations with heavily keratinized Surfaces
Conclusion: The structural and functional integrity of the lingual papillae are dependent on their intact trophic nerve supply. Extra care should be given to avoid the unnecessary nerve trauma during anesthesia or surgery