picture 2.
Cool the area with a coolpad, alternatively apply topical or inject
local anaesthetics. [2]
Now inject 3-5 BU (Botox Units) per cm² in 0,1mL solute. Therefore,
inject superficially into the dermis. Weakening the facial mimetic
muscles is unlikely if you not inject anterior to the front border of
the masseter muscle. [2]