R.O.O.T.S. Flo Rida
Her lips taste good to kiss and also kissing her can cause an erection.
You get cavities from sugar, which is another term for female bodily fluids. If he comes in contact with a lot of it, because of having various relations with females, then he would supposedly get "cavities".
FloRida is saying that, as part of a romantic encounter, he has animalistic urges to playfully and softly bite a woman's lips using all his teeth. he claims to have 42 teeth instead of the standard 32, or may be counting his grill (fashionable mouthpiece)