Jonathan M. Abenaim, DMD, DICOI

Many different issues can be happening. Here is some advice on what should be checked1-3d Scan to see if the root canal is completed correctly and if any areas were missed2-3d scan to see if the tooth has a fracture not able to be seen on an X-ray3-if all above checks out to be normal, have your dentist check your bite.4-another possibility can be the crown is very close to your bone or your crowns are too large
So many different issues can arise from complicated to simple. Be sure to have your issue taken care of, as living in pain and not being able to chew is not fun.

Many patients who are looking for "dental implants" seem to focus mostly on cost. Remember it's not about how much it costs but most importantly what you really want. Your smile? Your function? Feeling better?

So many things can change the cost of your treatment. Your practitioner should sit with you and discuss your wants and your goals. Once you have determined that , your implantologist can go over many different options as the world of dental implants is so diverse, there is something for everyone.

Good Luck

Your concern is understandable. Changing the crown , may not necessarily make if look better. Your smile analysis is important and your expectations are even more crucial. If I understand correctly you had the implant placed when you were 16, you were probably still growing that being said your implants can prevent your growth in that area while the rest keep going hence your length discrepancy. Regardless, there are many options for you to get the killer smile you deserve. Make sure you pick the practitioner who understands smile design and not just making crowns.

I am sorry on behalf of the proffession that you are not happy with your teeth. Good thing is that:
1-You have dental implants
2-you are still in temporaries.

That being said, I see from the pic you posted that your teeth itself may be too pushed out and too long. But again I only can see a small blurry photo. 

Find an implantologist that not only specializes in the surgery aspect but also in the tooth/restorative aspect of dental implants. They can use your speech and smile to help guide the position of your teeth and size. They can then use your facial expressions and musculature to help guide the rest.
Good Luck

"Cheap Dentistry is NOT good and Good Dentistry is NOT cheap"

Having a full mouth of implants is not a simple situation. Your teeth will be used 24hours a day and will want to be done right the first time. Our practice has thrived on fixing "CHEAP DENTISTRY", unfortunately it costs more to do it right the second time around. 
That being said, set your goals on what you want "DENTAL IMPLANTS" to do for you and then discuss with your implantologist what options are best for YOU and not for your DOCTOR. 

Dental implants have a myriad of options for all financial budget. Remember regardless of the options they should all look good and natural in the end. The big difference in cost will be the way they function. Think of it as you need to get from point A to Point Z. 
Bike-Old car-New car-Race Car 
or in terms of a marathon.
Heals-clogs-sneakers-great sneakers.

Dont despair find the right provider and they will do what is best for your needs!