your treatment depends on many factors:-
1) your upper wisdom of same side is present or not- if your upper correspondent tooth is absent get it extracted. if it is present then dentist
has to evaluate how complex the tooth root morphology is .
2) wisdom tooth normally have curved and fused roots, so your treatment depends on the x-ray investigation. if roots are in the favorable pattern and can be negotiated prognosis will be good.
3) if the decay is very deep and reached the root level get it extracted.
before any procedure get an X- ray done and check for upper wisdom.