21D Clinical Ltd | 859 followers on LinkedIn. 28th Fastest Growing Company in the UK. - Sunday Times. UK's Provider of Full-Mouth Dental Implants. #MedTech | 21D is a healthcare and technology business in the field of guided full-mouth dental rehabilitation. 21D has created and provides a full jaw implant rehabilitation solution using a fully computer-guided implant delivery system, enabling the delivery of implants and fixed prosthetic teeth in one hour or less per jaw in 95% of cases that need it. It is a modern and precise way of delivering an all-on-4 or any all-on-X rehabilitation. Titanium implants and prosthetic teeth were pioneered in the 1970s.