Lateral window or crestal approach sinus lifting??

Left sinus lifting (lateral window approach method), b-TCP + HA + FDBA, collagen mem.
 

 nice bone healing and implant surgery after 6 months


another sinus lifting case (not my case, my boss..) :
 
right crestal sinus floor approach (PRF + FDBA)

oh... amazing result, perfect sinus floor bone gain

Why????????????