Abstract
Observation of 26 temporal bones with replacement tympanic membrane revealed that most of the spontaneously replaced tympanic membranes had a certain thin intermediate layer. Histological findings of the border part between the replacement membrane and the remaining one indicated that the epithelial migration played the most important role in the mechanism of perforation closure.
Replacement membranes produced as a result of the conservative closure method and myringoplasty were also observed by light- and electron-microscopy, and the histological structure of the former closely resembled that of the normal tympanic membrane.
