Options for single tooth replacements?

My question is in regards to an upcoming dental extraction of #20 and #21 will have a 3 surface filling. So what are the options here, I can't do an implant this year I also want to hold on to my other teeth forever really so high speeding away healthy teeth is not going to help me do that. I know it is not typical but can a Maryland bridge work? Is there any option that will allow me to replace 20 fix 21 . I will plan to go back and do an implant for this tooth in about a year and half.