Mandibular dental implant with no posteriors: Prognosis?

It should be no different than if she had posterior teeth after the implant has osseintegrated. However, the prosthetics may be prone to screw loosening issues due to the horizontal load. You may avoid this with a one piece implant, but depending on the dimensions of the ridge, this may not be the best option. Functionally speaking, the time and expense of grafting this region to maintain or regenerate adequate buccal plate dimensions might be better spent on some posterior implants to retain her existing partials.

I would love to give you my suggestions, but I need to see a proper xray, or ct scan, and a photo of the area...without this information, it is impossible to comment....

I rather than a one piece implant , would use a two stages implant like the ones of Leone System ( conometric connexion with NO SCREWS ).

You can overload an implant easily if you are not careful. No posterior contacts means overloading the anteriors. It becomes a game of luck if you choose to allow this to happen around an implant. Spreading the forces of occlusion over the entire arch is always a good idea.

I would expect the implant will probably last longer and better than her remaining teeth (as long as proper treatment criteria are carried out). The advantage is that she would then have at least one implant for an implant retained denture in the future. Another 2 or 3 could be provided when required. Unfortunately you have not provided enough detail (and no radiographs) for a proper recommendation. However I find that often if you place some posterior implants (is this possible or are finances or lack of bone an issue) then you can provide a very retentive, mainly implant borne part denture which the patient will easily tolerate. I am sure you will get many more suggestions if you could provide more information.

If relevant suggestions are desired one should provide the details or else u will get general suggestions which will not be case relevant ! So please do that !

Failure to ensure posterior bite will result in anterior bite collapse with labialization of the ant groups both upper and lower (to a lesser degree) resulting in more load on the implant and definitely affecting its longevity. I would recommend a minimally invasive bridge to restore the missing incisor and invest if possible posteriorly up to the 2nd PM. Patients tend to accept our treatment options generally if we hammer more on the post op prognosis

possibly take the crown slightly out of contact and use a sleep splint?