<prompt> Most commonly involved ossicle in CSOM isMalleusIncusStapesAll the above  <response>: Ossicular necrosis is one of the sequale of CSOM. Most commonly, long process of incus gets necrosed. Sometimes, stapes superstructure also gets necrosed. This increases the conductive hearing loss to more than 50 dB Ref: Diseases of ENT by Dhingra 6th edition Pgno : 73 