Both Sculptra and Ulthera produce a thickening/firming effect through similar, but distinct, mechanisms. Sculptra is an injectable filler comprised of a suspension of disolvable particles that are similar to disolvable suture material. As they dissolve, they cause inflammation that results in collagen formation that produces the filling effect. The process takes 6-8 weeks. Ideally Sculptra is injected 3 times, about 6 weeks apart, to produce maximal effect.
Ulthera heats and perhaps mechanically injures the deep layers of the skin and the subcutaneous fat using focused ultrasound (sound waves). This likes results in inflammation that causes collagen to form, similar to a burn effect. This process takes longer than Sculptra; it takes 3 months or more to firm the skin.
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