IN RECENT years, numerous methods and materials have been used in reconstruction of the defective ossicular chain. However, in such reconstructive procedures it is still often difficult to predict the results. The experiments described in this paper were intended to throw light on some of the problems concerning the reconstruction of the ossicular chain in cases where incus is defective or missing and the eardrum, malleus, and stapes are intact. The subject is a broad one so our work is limited to (a) a brief review of the materials generally used in ossicular chain reconstruction, (b) observations regarding certain intratympanic measurements which seem to be important, (c) observations on the effect of tension in the conduction system resulting from reconstructive procedures and (d) a selected number of techniques applicable to defects ranging from absence of the lenticular process to absence of the entire incus.
Measurements of Sound Transmission.—