Why Is My Hearing Decreasing After 3 Stapedectomies In My Ear?

Hi All,

I have thrice undergone stapedectomy of my right ear. Recently on 6th March 2010.
First 2 times it was told that the Teflon piston had slipped.
Initially I can hear very well but gradually the hearing decreases. Please let me know how this problem can be solved.

Thanking in anticipation.

Thanks,
S,lesh
Cell No : 0000