Is a dental bridge really necessary? Does it prevent shifting, breakage?

Probably. Bridges are usually helpful. Ask your dentist to fully explain why.
Depends. All depends of how your teeth come together. If the missing tooth was the only one touching the tooth on the opposing arch, yes, the second one will shift. If there were other teeth touching, it will stay put. In terms of adjacent teeth (the ones next to the space), all depends of how well your upper and lower teeth come together. It is harder to predict that one.
Your decision. A dental bridge will stabilize your bite and should prevent shifting.
Yes/yes. Tooth replacement of lost teeth is important and yes, it does prevent the anterior tooth from drifting backward, the posterior tooth moving forward, and the opposing tooth from extruding. That's why retaining natural teeth is important.Also when teeth are lost, the bone level around the area decreases. Don't forget missing teeth can also be replaced w implants!
Yes and no. Dental "bridges" have many benefits (tooth replacement, better function, esthetics, prevention of tooth movement, etc.) as long as the bridges are fixed, or cemented. If the "bridge" is removable, the literature is vague whether a removable partial extends the lifespan of the remaining teeth.
Yes. It is important to replace missing teeth to prevent shifting of teeth which can cause problems with your bite and resultant damage to adjacent and opposing teeth. Another good option are dental implants. Have your dentist evaluate you for both options.
Yes. Especially if it is well designed and well made. Don't shop for price. Look for quality. This is part of your body that you will use every day.
That Depends. Is it important to you personally to have the missing tooth/teeth replaced? Some people get along fine with a hole. A bridge or implant does prevent adjacent and opposing teeth from shifting. Teeth naturally shift together to try to fill in a gap. Depending on how many teeth are missing, consider the benefits of a dental bridge, implant, or partial denture and see what fits your lifestyle best.
Yes . Replacement of missing teeth with a permanent bridge is important to prevent adjacent teeth from shifting .
Yes and yes. If you have all your teeth, you will be able to chew better (helps the digestion), the moment youloose some of them, the system doesnot work efficientlyand yourremaining teethwill start shifting. Please get a bridge asap.
Depends. There are reasons why a dental bridge is recommended. You should discuss with your dentist the reasons as to why he is making his recommendation and if you still have concerns seek a second opinion to confirm this recommendation.