Implantology is a part of dentistry dealing with replacements in the case of partial or total loss of teeth. Dental implants are substitutes for the roots of missing teeth.
When a tooth has to be extracted, in some cases the implant can be inserted immediately after the extraction and a provisional tooth can be placed over it for the duration of osseointegration (mostly 3 to 6 months).
Once the implant has bonded with the bone, the prothetic part of the process can be completed within a week, whether it is a single crown, a bridge or even a 10 or 12 teeth construction.
If the patient has a toothless jaw, 4 or 6 implants can be inserted to serve as a base for the future denture, which can be fixed and still retain the possibility of being removed by a dentist if necessary.
Such constructions are known as "all on 4" or "all on 6" systems.