Tympanoplasty type II with ionomeric cement and titanium-gold-angle prostheses

The pronounced isolated erosion of the long incus process is a challenging situation during tympanoplasty. Here, we report two methods for reconstruction of the ossicular chain as tympanoplasty type II with the incus remaining in situ. (1) lonomeric cement is used, resulting in two characteristics: a direct link between stapes head and the long incus process is achieved. At the stapes head the link possesses a joint allowing physiological movements between incus and stapes. (2) Titanium-gold-angle prosthesis according to Plester were crimped to the long process of the incus and positioned onto the head of the stapes forming an articulation.

Forty-five patients with missing long incus process underwent ossiculoplasty among which 41 patients were operated within a randomized, prospective clinical trial. For myringoplasty, the underlay technique with tragus perichondrium was used in all patients.

We investigated hospitalized patients.

In 26 patients ossiculoplasty was performed as tympanoplasty type II, in 19 patients with incus interposition.

The essential criterion was the postoperative air-bone-gap (dB).

Incus interposition achieved less satisfactory results with an average remaining air-bone gap of 10-20 dB. By contrast, the two tympanoplasty type II procedures yielded average postoperative air-bone-gaps of 0-10 dB (p=0.0003 at 1 kHz; p=0.0028 at 4 kHz), thus reaching the "gold standard" of stapedotomy. The two type II procedures, however, were not equal. The angle prosthesis was restricted to cases with a sufficiently long incus process, whereas the cement-technique is also applicable, when only a short part of the long incus process remained.

In the present study we show that in the case of a missing crus longum of the incus, a tympanoplasty type II achieved a statistically significant better hearing gain than an autograft interposition.