Do you mean, add an actual MIDI pitchbend, or just a symbol?
No, for the former… as with any controller, you would need to stipulate a length. (The only controller with variable length that can be inserted into the Score Editor would be done via the crescendo/decrescendo “scissors” when used as Dynamics Mapping, and you’d have to set that up in the Key Editor first anyways 
)
As regards symbols, however, there are a couple of diagonals and “falls” that may give you what you are looking for (but they are of course purely “graphic”).