If a licensed veterinary technician can perform a single layer closure of skin, I do not see why he/she cannot close a gingival flap as well under proper supervision.  I believe it is at the discretion of the veterinarian as to whether or not he/she allows the technician to perform the closure, but it should NOT be illegal for the technician to perform the closure.  As such, if a licensed technician wants to do the closure, and the veterinarian has confidence in him/her - then go for it!