What is the best treatment for missing 1st and 2nd premolars.

There are three primary options:1 Bridge  a. advantage=  fast and easy   b disadvantage  =  Have to prepare teeth and if a similar problem occurs have a biggger space2. ImplantsIf bone is good two implants , abutments and crowns.  Bone graft if necessary1or 2 surgical procedures, increased cost but when finished easier to care for and n teeth prepared.Both procedures are excellent and can last a lifetime and both require care.Itis also possible to do removable partial  

There is no xray to evaluate your present bone condition.  Treatment plans can include several options.  Theses include fixed bridge therapy or implant care. Based on condition of the adjacent teeth ( did they have large fillings or crowns..or are they relatively virgin teeth?)  If no previous or large restorations were done consider implants if the bone is good or need minor grafting.  If , however the adjacent teeth have already had large resorations including crowns consider a 4 tooth fixed bridge using the 1st molar and the long rooted canine for anchorage.  Again, I have not seen xrays but a discussion with your dentist based on his/her xrays and experience should help resolve this issue.