The sort of night time resting splints that I am talking about are designed to maintain full finger extension, which splints that only support the wrist and thumb will not do.
Mine are made of aliminium which is very stiff but can be adjusted to fit the hand and arm, and covered with soft cushioning so they are very comfortable. They hold my fingers out in a fully extended position. I alternate which hand I wear them on as they totally imobilise the hand (can't even pull up the duvet with a hand wearing a resting splint). I have the regular working splints for the daytime to allow me to use my fingers.
I will try and find a link to show you what I mean. Do not allow your fingers to stay balled up all the time esle you will develop contractures.
The top splint in this link is very like mine (it is even the same colour). Notice how it extends the fingers out to prevent contractures. No clues why they say it is for geriatric use, people of all ages use them.
http://www.nextag.com/hand-splint/shop-html
hth
raglet