There are two main types of lasers used to treat wrinkles- ablative and non ablative. The only difference between the two is the intensity of the heat. In reality there is no difference because if a non ablative laser is used at high power for a prolonged time, it can do the same thing as ablative laser. The philosophy behind laser treatment for wrinkles is that heat generated penetrates the skin and restructures the underling tissues. The supporting tissues beneath the skin are stimulated to grow- this causes tightening of skin, evens texture and lessens wrinkles.
Lasers unfortunately do not work in one session. Depending on your wrinkles, you may need many sessions. The newer lasers also are less painful- they have tip which is automatically cooled so that you do not feel the heat as much. There are many types of lasers and the type may depend on your skin tone and intensity of wrinkles. There is no laser which can permanently cure your wrinkles but they can make your face looking young and pretty for several months. The one major downside to laser is the cost. If you have the money, then it is worth a try.