Dental implants offer multiple advantages over dental bridges. The following video explains the Pros and Cons of both in very easy to understand language.
https://www.youtube.com/watch?v=2fYXNhMnz_E
Bridges:
Pro 1: They are very quick. A bridge can be finished in as little as a day if the dentist has an in-office CEREC machine. If not, the bridge can usually be finished in a week or two by sending it to the lab.
Con 1: Bridges require teeth adjacent to the missing tooth space to be cut.
Con 2: When teeth are cut for bridges, they sometimes end up needing root canals.
Con 3: Bridge teeth can still get cavities.
Con 4: Bridge teeth can still get cracks in the roots.
Con 5: Bridges have a lifespan of only 10.1 years according to some studies.
Con 6: Bridges do not preserve bone. The longer you have a bridge, the more bone you can lose at the spot where the tooth is missing.
Implants:
Con 1: Dental implants are a slow process taking up to 3 months to heal before the tooth can be put on the implant.
Pro 1: Dental implants have up to a 98+% long term success rate.
Pro 2: Dental implants do not decay.
Pro 3: Dental implants do not crack.
Pro 4: Dental implants do not require the cutting of additional teeth.
Pro 5: Dental implants do not need root canals.
Pro 6: Dental implants can be placed in positions where bridges cannot (ie. the last tooth in the mouth.) A bridge cannot be placed here because there is no back tooth for the bridge to sit on.
The cost of a bridge and dental implant are about equal. If a bridge ends up needing root canals, the bridge will cost more. If the dental implant requires bone grafting, the implant will cost more. One thing to consider is that if you get a bridge and it fails you are back to square one and you will now need to get an implant anyway!
Hope this helps!