A 2017 study compared the effects of different mattress materials on body pressure distribution during three different sleep postures; front-sleeping, back-sleeping, and side-sleeping. The study found that a latex mattress was preferable to a polyurethane mattress, distributing pressure more evenly across the body for all three sleep postures.
Given the above, a front sleeper using a polyurethane mattress may benefit from adding a latex mattress topper. Doing so may help to distribute their body weight more evenly, ensuring a more comfortable sleep.