Rinne's test was negative in the right ear. Possible diagnosis is

There is conductive hearing loss in right ear. Left ear normal. A prediction of an air-bone gap can be made if tuning forks of 256, 512 and 1024 Hz are used. A Rinne test equal or negative for 256 Hz but positive for 512 Hz indicates an air-bone gap of 20-30 dB. A Rinne test negative for 256 and 512 Hz but positive for 1024 Hz indicates an air-bone gap of 30-45 dB. A Rinne negative for all the three tuning forks of 256, 512 and 1024 Hz indicates an air-bone gap of 45-60 dB. Ref: Dhingra; 6th Edition; pg no 22