Implant, sandwich (6)
I believe the answer is:
insert
This clue is a double definition.
'implant' is the first definition.
(thesaurus)
'sandwich' is the second definition.
(thesaurus)
(Other definitions for insert that I've seen before include "Loose sheet within magazine" , "Place (something) inside (something else)" , "Push into" , "Place within, pages of a publication say" , "Enclose" .)