Can I remove the implant and leave it without grafting?

Depends on why it failed.

Yes , why not , but don't choose the same site for reimplantation then! The quality and quantity of the bone will be low because of resorption as well as due to less no. of osteoblast and if u graft then theoritically u can place an implant after 3-4 weeks but i usually suggest to place after 3 months , let the graft resorb

This is a topic that could get lengthy. The implant can fail for varied reasons, but once the implant is removed, the site heals in the same manner. It is not mandatory to graft the site of a failed implant that is removed, but if the area allows, it is always a good idea, especially if you are planning to go back and place another implant at a later time. You want to remove any infected tissue, fibrous encapsulation tissue, etc.. by carefully curetting the site to expose the bone and create bleeding from the bone. This will allow a source of cells and factors to promote angiogenesis in the area and start infiltrating the clot or graft material. The number of walls in the defect also influences the recommended treatment. It would require several months for the bone to regenerate, unless the area permits the placement of a wider implant, in which case no waiting time is necessary, and sometimes it is done immediately. As a dentist, even if you do not place implants, it is important to familiarize yourself with bone biology and healing. Good luck and I hope this helps

said Carlos....... we must start to understand the reasons for the failure in the ifrst place; and take the time for the pathogens and unhealthy cells to vanish...................." from my mouth to God's ears"