The recent accident with An-22 which took off from Voronezh, headed for Tver air base "Migalovo" and crashed near the city of Tula on December 28, 2010 has recently been investigated. The aircraft was 36 y.o.
One of the causes of the crash was the failure of thrust levers and other technical problems, not the pilots' error.
An-22s ceased operations till the end of the investigation.
But neither An-22, nor Tu-95 are grounded! They are still succesfully operating in Russia, e.g. 6 An-22 are in Russia Air force and army.
Tu-142s are less numerous, but they're also not yet grounded.
My opinion: these types are very old and time-worn, but we have nothing to replace them(