Long span bridge with two teeth supporting the dental bridge has GUARDED PROGNOSIS.You are having a 6 unit bridge, with 2 abutments , meaning teeth supporting your bridge, in area which you chew, I would be hesitant to go that route.Why don't you have dental implant consult ? if you do not want dental implants, or you are against dental surgery, then know that it might fail, and your dentist needs to inform you.The bone level and the length of your roots, will directly impact on how long the dental bridge will last you.Usually, we do a treatment plan for that long span bridge for patients who absolutely insist on having fixed permanent teeth WHILE we have placed implants in pontic sites, and we are waiting for healing and activating the implants for use.