Maryland bridge could be a good option for missing tooth?

A cantilever bridge or a Maryland bridge is a concept that ends up costing you more than you expect. Imagine eating at the end of a table that's supported on one side only. Even if they're cemented into the ground, the strain on the G's of the one side is tremendous. So the tooth that holds the cantilevered crown suffers this great strain also with use-eating, grinding, etc. What happens to the tooth is bone loss, fracture of the bridge or tooth and ultimate tooth and bridge loss. And you're left with a bigger problem. 
If you're able to place an implant, that's the best long term solution. An equally good long term choice is the three unit bridge. The so-described "table" is supported by four legs. Don't sacrifice solid design and known success for the idea of "conservation of tooth structure". You'll be happier in the end. 

A Maryland bridge is not a bad option for a front tooth if the adjacent teeth are not compromised. I wouldn't usually recommend a Maryland bridge for back teeth due to the amount of pressure placed on back teeth. It could easily break. A Maryland bridge might be considered temporarily in the area of a missing back tooth while waiting to have an implant placed, but since you said that is not an option for you, I would recommend a bridge for longevity.