Does Curly Hair Make a Difference in Hair Removal Treatments?

There are several factors that determine results for laser hair removal treatments, but curly or straight hair is not one of them. They are:

Skin Color
Hair Color
Coarseness of Hair
Type of Laser
Experience of Practitioner

Laser Hair removal works by a process known as photothermolysis wherein laser light is focused on an area of skin and hair. The laser energy is absorbed by the pigment in the hair follicle, which heats up and is destroyed. The more pigment in the follicle that is responsive to the laser light, the more heat generated.
The laser does not know the difference between hair, skin, teeth, bone, or the fabric on your shirt. Along the same lines, it does not effect a different response in curly or straight hair.

There is no difference in the efficacy of hair removal in curly or straight hair. The way the laser works is the energy developed by the laser seeks the pigment in the "root" of the hair just beneath the skin.
The coarser the hair and the more pigment the more effective it seems to be.
In our office we ask patients to shave the day before treatment. You don't want to wax prior to laser hair removal, as there will be no hair left in the follicle to absorb the energy.