{HEAD ~ and covers} having perimetric depressions for fitting the covers to said prism boxes, such that when said covers are removed it is possible to reach through said prism boxes for fixing {TAIL ~ the edges} of the orthodontic models positioned between said prism boxes 
{ HEAD ~ and covers } having perimetric depressions for fitting the covers to said prism boxes , such that when said covers are removed it is possible to reach through said prism boxes for fixing { TAIL ~ the edges } of the orthodontic models positioned between said prism boxes
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH