how can I fix my rubber plant?

My rubber plant is about 6 years old, six foot high, very strong and healthy green leaves, but during a very cold snap while we were on holiday the leaves have all gone brown, dry and are falling of.If you scrape the trunk its is still green underneath and there is a small shoot with four green leaves right at the base of the trunk, but all the rest of the leaves are dead.What if anything can I do to bring it back as it was?