Root analogue dental implant
A root-analogue dental implant (RAI) – also known as a truly anatomic dental implant, or an anatomical/custom implant – is a medical device to replace one or more roots of a single tooth immediately after extraction. In contrast to common titanium screw type implants, these implants are custom-made to exactly match the extraction socket of the specific patient.
Source: Wikipedia — Root analogue dental implant (CC BY-SA 4.0)