Seventy-four patients undergoing bone pate repair of the long process of the incus as part of a tympanoplasty are presented. Mean follow-up time was 66 months (range 12–143 months). Hearing results are averaged over the frequencies 500, 1000, 2000 and 4000 Hz. Thirty-two per cent of the patients had hearing thresholds better than 30 dB pre-operatively. A significant improvement in hearing was seen (p<O.OO1). The data were also analysed to assess the effect of the pre-operative state of the tympanic membrane on the final result. The pre-operative condition of the tympanic membrane was either perforated (35 ears) or atrophic (33 ears). Six tympanic membranes were intact but these were excluded from the final results. No difference in hearing result was found between patients who had an ossicular repair in combination with either a perforated tympanic membrane repair or an atrophic membrane repair. Average hearing gain in the perforated group was 13 dB, in the atrophic group 9 dB and in the intact group 7 dB.

The human cadaveric styloid process was used as a homograft material for ossicular chain reconstruction in 41 cases of chronic suppurative otitis media over a five-year period. Although technical success was achieved in about 88.23 per cent of the cases, actual patient benefit was around 70.58 per cent; this is comparable to results obtained with most other homologous graft materials. The problem of breakage while remodelling the bone has also increased the risk of transmitting the AIDS virus and consequently undermines the use of this material.

The masses of preserved ossicles and cortical bone grafts have been studied in vitro using a Stanton Unimatic CL41 balance. The cortical bone grafts prepared for use in malleus-stapes assemblies had a mean mass 28 per cent greater than that for an incus, while those prepared for use in a malleus-footplate or drum-footplate assembly had a mean mass 58 per cent greater. Analysis of the hearing results for the first 20 ossiculoplasty operations performed by the author using cortical bone grafts revealed no significant differences in outcome attributable to increased mass. However, large grafts did become fixed to surrounding structures in some cases.

This paper describes the results of a comparative audit of the costs of using artificial prostheses and cortical bone. The costs of using a bone graft have been calculated by estimating the expenses incurred as a result of the additional time required for preparation of the grafts. The mean cost of preparing a graft was £29.10, while the mean cost of using a prosthesis was £65.01.

Concern about the possible risk of viral infection being transmitted by the use of homografts has renewed interest in cortical bone autografts as an ossicular substitute. Over the last four years I have used cortical bone on a regular basis. Comparison of hearing results obtained using ossicular and cortical bone grafts shows no significant difference between the two groups. Cortical bone appears to be satisfactory material for ossiculoplasty, but long-term studies of outcome are required to confirm this.

One hundred and sixty-five cases of different kind of ossiculoplasty in patients suffering from chronic middle ear disease were performed at the ENT department of Papanikolaou Hospital in Thessaloniki, Greece, during the years 1988–1990. There were 40 cases of incus transposition, 47 cases in which polyethylene TORPs and PORPs were used and 77 cases of hydroxylapatite prostheses (41 TORPs and 37 double notch PORPs). Hearing success was defined as a post-operative air-bone gap of <20dB. According to this criterion 74 percent of the incus transposition cases were successful, 61 percent of the polyethylene TORPs, 65 percent of the hydroxylapatite TORPs, 40 percent of the polyethylene TORPs, and 89 percent of the double notch hydroxylpatite PORPs. It is obvious that ceramic PORPs produced the best results, while there was no statistical difference, regarding the hearing improvement, among the different kinds of TORPs which were used. Extrusion rate and other kinds of complications are also discussed, as well as a case of severely damaged ceramic TORP, within two years due to middle ear infection.

The long-term results of 63 total ossicular chain reconstructions using autografts is presented. The follow-up period ranged from 18 months to 18 years with an average of 8.5 years. The primary aims of the study were firstly to assess the long-term success rate and to find out if there were any hitherto unknown causes of bone graft failure. In the event, it was found that the recently described anatomical variation of the oval window viz., the deep oval window, was the prime cause of failure in 32 per cent of unsuccessful cases. Some measures to help to mitigate this problem, are suggested. The result were assessed on the basis of:

1. A minimum gain of 20 dB HL in air conduction (Technical success). The success rate was 55.5 per cent.

2. Patients benefited using Smyth and Patterson's criteria in conjunction with the Glasgow Benefit Plot; 54 percent of the patients benefited significantly.

This study was set up, prospectively, to determine factors affecting the long-term hearing results of patients undergoing incus transposition as a second stage in ossicular reconstruction, following a successful drumhead repair in non-cholesteatoma ears. Seventy-one patients were entered into the study over five years from 1980–1985, 66 were available to be studied throughout the five year follow-up period.

Nine weeks post-operatively, 74 per cent of all patients has an air-bone gap of less than 15 dB (48/66). The type of first stage procedure had a significant effect on the hearing levels in the final five year assessment. The most successful sub-group were those patients who had a cortical mastoidectomy and silastic sheeting inserted in the first staging procedure. The air-bone gap, of less than 15 dB, was maintained in 71 per cent of this group (17/24). The sub-group who had a simple myringoplasty as the primary procedure had a good initial hearing level. By five years, however, only 30 per cent of the patients had maintained the air-bone gap of less than 30 dB (3/11).

Successful replacement of the sound conducting mechanism of the ear has been hampered by infection, perforation, prosthesis instability and extrusion. In this animal study on thirty rats a silicone prosthesis was inserted between two layers of fascia as a total replacement of the tympanic membrane and ossicular chain. After four months the graft was found to be intact without evidence of infection or extrusion in all but one of the 30 rats. These results justify a trial of a similar silicone prosthesis in humans.