Implant V/s Bridge???
First of all it is important to understand that what are bridges and what are dental implants and what are their Pros and Cons ?
These are both option for fixed replacement for the missing tooth.
1) Bridges is used for single missing tooth or multiple missing teeth. In this both the adjacent teeth to missing teeth are used as a pillar to support the Artificial teeth for a missing teeth , i.e. On both the adjacent teeth crown cutting is done than cap are given such that the missing teeth is attached to these natural tooth cap.

Bridge to replace a missing tooth
This natural tooth cap can be made of many materials like :-
1)Metal( Require around 1.5 mm of tooth cutting )
2)PFM (Porcelein fused to metal )( Require around 2.5 mm of tooth cutting )
3) All ceramic (These are most conservative as require only .8-1 mm of Tooth cutting )
Disadvantage of bridge over implant :-
1)The biggest disadvantage of bridge is that adjacent tooth need to be trimmed and grinded just for the sake to replace a missing tooth .
2) Also load of three teeth ( two adjacent and one missing ) is over two adjacent teeth so can lead to bone loss over a period of time . It has been seen around 30 percent of bridges fail in 7 – 15 years .
3) Oral hygiene :- Oral hygiene can not be maintained that well , that can be done with Dental implants as the surface towards gums of the missing tooth always has some food lodgement over a long period of time and causes problems of bad breadth and tissue inflammation .
4) Aesthetics :- bridges can not meet the aesthetics that can be achieved with dental implants as in implants each tooth stands alone with no attachment to adjacent tooth
2)The other fixed teeth are DENTAL IMPLANTS . Dental implants is the call of the day and answer for every person having some missing teeth or where all teeth are missing .
The biggest advantage of implants is :-
1) No damage to adjacent tooth .
2)More aesthetic
3) Better hygiene
4)Forces along the long axis of tooth.
5) More long term results with better predictability .

Single tooth Implant
To summaries dental implants are best and more long term aesthetic option for missing teeth .
Dental Implant VS BRIDGE
Implant | Bridge | |
Damage to adjacent teeth | No | yes |
Oral hygiene | Like natural tooth | Difficult |
Aesthetics | Like natural tooth | Like natural tooth but less than implants |
Force distribution | Better (along long axis of implant) | Over adjacent tooth to missing teeth |
Longetivity | Life long | 5-10 years |