Based on the provided reference, the individual initially attempted to use a hot comb but switched to a curler (presumably a curling iron or wand) to straighten their roots because they kept burning themselves with the hot comb. They found the curler effective for straightening their roots.
Therefore, to answer your question directly, based on the user's experience: you can straighten your hair, including the roots, during a silk press by using a curler (like a curling iron or wand) as an alternative to a hot comb, especially if you're finding the hot comb difficult to manage or are prone to burning yourself.