We read the letter titled "Comparison of Two Anticoagulants for Pain Associated with Platelet-Rich Plasma Injections" authored by Pensato et al. in Aesthetic Plastic Surgery. The authors emphasized an important point. PRP treatments have a lot of variables; preparation method, application, amount of PRP injections, and content (such as number of platelet concentration, presence of leucocytes, and pH). However, in our study, we focused on the pain of injections. We showed that there is a pain difference by using different anticoagulants during PRP preparation, but we did not investigate for possible reason of this pain difference. The use of different anticoagulants may have caused changes in the content, and these alterations could be responsible for the variation in pain. Researches could be done to investigate the reason and the physiology of this effect.
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