Abstract: Dental implant has become a common therapy for the patients requiring complete-arch rehabilitation with severe periodontitis. However, there are still some arguments on the timing of implant placement. This review will discuss the timing of complete-arch implant rehabilitation for the patients with severe periodontitis in four aspects: infection control, keratinized mucosa, pre-operative esthetic and function assessment and surgical guide template.

Key words: severe periodontitis, complete-arch implant rehabilitation, the timing of implant placement