Ali Shojania, DDS

it will have a ripple effect on the fitting of your other Aligners . The second one will barely fit; then the Teeth stop tracking the Aligners. So I would go back and wear your Aligners 22 hours a day for two weeks then change to the next Aligners. You will save time in the long run

By looking at your picture, its better to do braces rether than invisalign; because your tooth #7 in the front is rotated too much. Also if you are pressed with time; or you don't like braces, you can pull #7 out and do a bridge

From your picture, you have 2 options:

1- traditional braces to expand your jaw, combined with intrusion and extrusion of your anterior teeth. ( 2 years )

2- full mouth reconstruction ; including posterior crowns taller than your present ones; to open your front bite; then extracting some of your teeth that are way out of line. And do crown and bridges

Need a cat scan first. Then if the width of your jaw is at least 5.5-6 mm, and the height to the nerve is 7-8 mm minimum, you don't need bone graft. You can place 3 implants ; wait 4 months; then make a 3 unit bridge. I don't personally too fund of bone graft in the lower jaw because of the compromised blood supply. If your lower right is not in good shape either, I would do a technique called ALL ON 4; which in my office, in 5-6 hours, we can pull all your lower teeth, and at the same time, not only place 4 implants; but also screw a fixed bridge to it at the same time ( no need for bone graft, and no temporary phase with denture ) you can walk out with new set of fixed teeth. 

Hopefully the crack is not deep enough to be in the nerve; if it is, Root canal therapy is also needed. Also if the crack extends more than 2 mm below the gum margin, most probably can not save the tooth and it has to be pulled, and implant replacement. As far as doing two teeth instead of one, if the lab is really good, they could almost match it perfectly to the adjacent tooth; other wise symetrical would look better. Being optimistic, you only need one crown or veneer to solve your problem :-)