I want to straighten my teeth before getting dental implants but I have a bridge & missing teeth. What are my options? (Photo)

In your case, physically straightening the teeth is impossible due to the multiple missing teeth.  However, with the right planning, you can have a great smile.  First, x-rays, photos and study models must be taken and analyzed.  If your midline is good on the one upper front tooth, that is a starting point.  A complete temporary bridge spanning from the upper right to the upper left can be designed on your study models.  Next, choose the color of your choice and have your dentist make a temporary bridge for all of the upper teeth including the missing teeth.  The dentist can now remove the existing bridgework, temporary crown and the old crown and place the complete temporary bridge over your existing teeth. 
During this trial period, you and the dentist can discuss any changes you wish to make.  Another study model can be made of this temporary bridge which shows the positions of the existing spaces needing implants.  A surgical guide can be made for the positioning of the implants according to the new temporary bridge.  
Now implants can be placed.  A few months later, all restorations can be finished.

If you perform a bridge,will be something more faster and within a couple of days you will have the results you are looking for,there are good materials on the market like Zyrconia that is metal free,and can be a good option for you,the only inconvenience is that you will start to loose bone on the area where you lost teeth,vertical and horizontal,which is bone that will dissapear,and provably some day you will need it.The best way to preserve the bone and to have that area like how it was is with Dental Implants that can be placed in just one visit,the only inconvenience is to wait at least 3 months for the osseointegration,and later on it will have a great result functional and cosmetic,for a long lasting term solution Dental Implants will be the best way to restore cases like yours,its worth the surgery and the waiting time,also search for a Dental Implant specialists so you will be in expert hands.Your case needs to have a good diagnose and a proper treatment plan,with a complete xray diagnose,but yes you will have a long term solution,with the results you always wanted.