• The action of the cat's mesotympanum, denuded of mucosa, to Silastic and gelatin film was studied and compared with the contralateral control ear, which was also denuded of mucosa. The ears were studied by horizontal pathological sections taken one, two, four, and six months post-tympanotomy and insertion of either gelatin film or Silastic. The Silastic, gelatin film, and control ears were compared for inflammatory reaction, amount of fibrosis, and the quality and quantity of mucosal regeneration. The inflammatory reaction was increased in the ears with Silastic compared with their corresponding control ears or to the ears with gelatin film. The amount of fibrosis and the quality and quantity of mucosal regeneration was essentially the same in the Silastic, gelatin film, and control ears. This study shows that both substances are well tolerated in the middle ear and that neither substance stimulated or inhibited the regrowth of mucosa or fibrous tissue when compared with the control.
(Arch Otolaryngol 102:547-551, 1976)