Wide Diameter 5.5 or 5.0 for Molar?

no need to use anything greater than 5.0 keep it simple and predictable . Looks like a fun case to do

may want to treat #15 first since it has a periapical radiolucency

You have peri-apical radiolucency/pathology on both teeth #13 and #15. RCT should be done on #15 and when drilling for the dental implant on #14, make sure you avoid the PAP on #13 that's encroaching around the apices of #14. A 5mm diameter for #14 is sufficient. As for tooth #2, I would go for 5.5mm diameter - you have the room for it and it's more surface area for the implant to osseointegrate with the bone.

The bicuspid and the Molars have Periapical lesions. It will be malpractice to place an implant until the pathological lesions are taken care. Once the problem is resolved, then a 5mm implant will be fine.

Get those PARL's fixed first

Without doubt, I would remove #13 and #15 and place 2 implants in those sites for a 3 unit FPB. With the PAs both showing radioleucencies, they both likely need endo. Why do endo when implants are so much more predictable?? Good luck!!

E Evans, I agree that both implants should be removed, with the caviat to let the bone heal and make sure that there is no pathosis in the area and then place the implant.

the dilemma of 5 or 5.5mm is not the issue here. I suggest you not to place implant at #14 now, periapical lesions may spread to the implant espacialy at the maxilla. treat 13 and 15 by endo (15) or extraction(13) and then place implants . also at #3 there is a periapical RL (palatal root) you should be cautious and if placing implant at #2 make sure to inform the patient of the matter.

This is a good case. I agree with some of you that perhaps the best most predictable thing to do is remove both #13 and #15. Just by the small area we see. Can you really trust #13 and #15. Something to consider but perhaps you can remove both #13 and #15, place implants #13, #14 and #15. Place one at no cost to the patient. Having three separate implants allows the patient to floss inter proximal. A implant bridge is fine but with all the treatment this patient already appears to have had, can you trust that they will keep up their hygiene well? People loose teeth for a reason.