Smartie is right, you can start watering again. Dend's like a resting period in the fall/winter time and will start to produce life again around March. I usually do a slow process of watering and eventually get back to a normal regimen within a few weeks. If the lost of leaves is alarming, don't be, this is the so called nature of the beast. You will be extremely happy with the results if your dends are left to rest.
Oh by the way....
Aboard, its great that you have ventured to the best orchid forum on the web. Please take a few minutes to go and introduce yourself listed "Break the Ice". The OB has so many members globally with various levels of knowledge. The only silly question is the one you don't ask, so please ask away as well as joining in on answers.