Conclusions. The results support bilateral sequential implantation for patients who are not completely satisfied after implantation of one side. Objective. To evaluate the benefit of bilateral Vibrant Soundbridge middle ear implantation as compared with unilateral implantation in quiet and noisy environments. Methods. This was a multicentric and retrospective study of 15 patients with symmetrical sensorineural hearing loss who were implanted sequentially in both ears. The performance of each subject was compared under three conditions: with the right implant activated, with the left implant activated, and with both implants activated. Audiometric tests were compared with self-assessment subjective evaluation by questionnaire. Results. Both qualitative and quantitative assessments demonstrated improvement in speech intelligibility, especially in background noise, but also for low voice intensity in quiet.