When injecting under the nose to correct a gummy smile, make someone appear more cheerful or happy than they normally are, or give someone a lip flip, it is vital to confirm that the patient has normal lip function.

You accomplish this by having your patient pucker his lips. The Cupid’s bow, the V in the center of the top lip, should remain in the same place on the face.

If the Cupid’s bow shifts to one side when the patient puckers, it indicates that one side of the lip is malfunctioning.

These treatments can cause your patient to lose their ability to control their lip muscles and, thus, will cause their drool to come out of their mouths.

So, before you begin any lower face treatments, ask the patient to pucker and make sure the V of the Cupid’s bow is in the middle of the face.