舌の化学的損傷に関する病理組織学的研究

低濃度酸, アルカリによる舌背表面の傷害を中心に

抄録

Tongue injuries are cuased mechanically, thermically, chemically and radiologically, although they are rarely observed clinically. Pathology and healing process of theselesions seem to have less been studied.
Thus, we examined chemically induced tongue injuries by acid or alkali substances, mainyinjuries on tongue dorsal surface, using experimental animals as a part of this study.
Wistar male rats of 6 weeks post partum were used as experimental animals. HC1 wasused as acid substance, while NaOH used as alkali substance. In order to give these injuriesunder constant conditions as far as possible, these experimental animals were generally anesthesizedwith Nembutal and a filter paper sufficiently soaked with HCl or NaOH was appliedto the anterior 2/3 part of tongue dorsal center. The concentration of each chemicals used inthis study was, 10, 20, and 30% with application time for 1, 3, and 5 minutes respectively.
Immediately after application for a given time, the anterior 2/3 part of tongue includinginjured site was removed as soon as possible and the damage on the tongue dorsal surfacewas examined by light and scanning electron microscopes.
In consequence the tongue dorsal surface was covered by well developed filiform papillaeand fungiform papillae having taste buds scattered among them, which was surely injuredeven when HCl or NaOH at low concentrations was applied for a short time. The degreeof injury with HCl was different from that with NaOH. Macroscopically, no remarkablechange occurred with HC1, although NaOH produced a change of color to dark brown.Histological and scanning electron microscopic examinations revealed more severely injuredfiliform and fungiform paillae and the epithelium of the interpapillary mucous membrane withthe increased drug concentration and prolonged application time and considerably destroyedtaste buds, suggesting functional disturbance. These injuries on the mucous epithelium showeda trend of detachment and epithelium with HC1, while NaOH tended to produce detachment, softening or fusion of epithelium.
In either case, the lesion was mainly superficial with less extension of injury into thesubmucosal tissue, remaining at Grade I or II of chemical burns in general.