Is it normal for dental implants to be shorter than normal teeth? (photo)

I recently got three implants in my lower left jaw. I got the teeth a couple days ago and a followup session is scheduled in two weeks to make sure all is OK. My concern is that when I chew something I feel like the grip is not 100%. And as seen from the picture I've attached the upper and lower teeth don't quite sit on each other. Chewing large pieces of food seems fine but as the pieces of food get smaller, I have to use my other side to be able to completely chew the food!