“…The impact of CaHA on aesthetic purposes can be explained through various reported mechanisms, including promoting cell proliferation, collagen production, angiogenesis, and the formation of elastic fibers and elastin [ 4 ]. The aesthetic effectiveness of CaHA has been investigated in several clinical trials and observational studies that report various degrees of improvement in aesthetic scales [ 5 , 6 , 7 , 8 , 9 ] and levels of patient satisfaction [ 10 , 11 , 12 , 13 , 14 , 15 ]. The majority of available studies reported a comparison between the aesthetic effects of CaHA following injection versus the baseline values [ 7 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ], and there are limited comparative clinical data on efficacy of CaHA relative to other categories of existing fillers [ 5 , 23 , 24 , 25 , 26 , 27 , 28 ].…”