The effect of single-layer and double-layer graft usage in tympanoplasty on hearing and graft success

In this study, we investigated whether the use of double layer graft (DLG) in tympanoplasty would increase grafting success rates (GSR) and whether increased graft thickness would negatively affect hearing.

The study group consisted of patients with DLG and the control group consisted of patients with single layer graft (SLG). The results of 195 patients in terms of hearing achievement and 211 patients in terms of GSR were compared.

Hearing and GSR were analyzed in 103 DLG and 108 SLG patients. Postoperative 6th month air conduction pure tone averages were 25.34 (±14.99) dB in DLG group and 20.50 (±8.82) dB in SLG group. These values were statistically significantly higher in the DLG group (p=0.005). Postoperative air bone gap was 11.40 (±8.61) dB in DLG and 12.95 (±10.88) dB in SLG and there was no statistically significant difference in hearing gain between the groups. GSR was 99/103 (96.1%) in the DLG group and 103/108 (95.4%) in the SLG group with no difference between the groups (p=0.679)

We concluded that DLG is not superior to SLG in terms of both hearing and GSR, and may even be disadvantageous in terms of hearing, and this should be taken into consideration in patient selection.