Extract and place 2 implants or retain and restore?

I would remove it because it is tilted and the root position will compromise implant placement, it takes up real estate due to the tilt.. I would place a three unit implant supported bridge, good place to start to restore vertical dimension of occlusion.

What is the periodontal status of tooth # 44. If you have low mobility, due the endo, post and core and crown tooth. Use implants to fill the rest of the space. Implants should be for hopeless teeth, not teeth that with treatment will provide years of use. Just my opinion, I have been doing regeneration on failing periodontal teeth for the past thirty years with excellent results. See the literature by Tonetti et. al which examines long term outcome of GTR on failing teeth and you will see the retention rate is in the 94% range long term. It just makes sense to hold on to natural teeth for as long as possible prior to placing implants.

First, if TMJ's have no problems and/or have been resolved with splint therapy, mounted models are the first step. From x-ray, #2 (#16) and #31(#46) appear to be out of normal planes of occlusion and are probably a huge interference with proper occlusion whether or not there is a need for an increase in VDO. Why have patient spend $$$ on RCT/crown on those teeth when they are most likely going to be interfering with proper occlusion and/or are not really necessary in the first place? I agree at a quick glance without enough information that #28 (#44) should be extracted and some type of implant therapy be used to restore the LR quadrant, but there is simply not enough information present to make an accurate diagnosis and treatment plan. Comprehensive dentistry in needed in this patient, if joints are resolved, start with mounted models and a diagnostic wax-up.

#2 is the 17; #31 is the 47. Take out the 44 so you have optimal site for implant placement for anterior abutment at LR. Distal to that site you will be limited to short stuff; don't hesitate to put two more in there if they are really short/narrow. Great suggestion with regard to full mock-up of desired occlusion prior to placing anything. Then you can also make surgical guides so your implants are in harmony with the desired prosthetic outcome. Lacking that kind of diagnostic info you can take anything you read here with a grain of salt. I will always sacrifice a single tooth (and sometimes more than one) in service of a more stable prosthetic outcome; that is what I would want in my own mouth. Others feel otherwise - perhaps there is more than one right answer depending on how you weigh the pros and cons. "Begin with the end in mind." - Dr. Stephen Covey