[Comparison of the results of incus interposition and artificial columella in tympanoplasty (author's transl)].

The average postoperative air-bone gap after interposition of an incus between tympanic membrane and stapes footplate is too high in case of missing crura of the stapes, it is 27 dB. The interposition of an artificial prosthesis, according to Shea and beeing made of "Platipore", leads to a statistically based lower air-bone gap with a mean of 20 dB. Concerning the change of bone conduction, there is no difference between these two methods of operation. The rate of artificial prosthesis which are perforating the tympanic membrane, increases after seven months up to 15%, but only 4% of the incuses invade the plane of the tympanic membrane after 22 months.