All-on-4
A full-arch implant rehabilitation concept in which four implants—two axial and two posteriorly tilted—support a fixed prosthesis, enabling immediate function without bone grafting.
Full Definition
The All-on-4 concept, introduced by Paulo Maló, uses four strategically placed implants to support a full-arch fixed prosthesis in edentulous or near-edentulous patients. The two posterior implants are angled at up to 45 degrees to avoid critical anatomical structures (inferior alveolar nerve, maxillary sinus) and to maximise implant length in available bone, thereby increasing primary stability and reducing the need for bone augmentation. The provisional prosthesis is typically delivered within 24–48 hours of surgery. Editors should render the name consistently as 'All-on-4' (not 'All on Four' or 'All-On-4') unless a house style dictates otherwise, and note that it is a proprietary concept associated with Nobel Biocare.
Usage
Usage note: Render as 'All-on-4' with a hyphen and numeral. It is a branded concept; in non-branded contexts, use 'full-arch fixed implant rehabilitation on four implants'. Distinguish from 'All-on-6'.
In Context
- "The patient underwent All-on-4 treatment in the maxilla, receiving a provisional acrylic bridge on the day of surgery." — Case presentation
- "Authors should note that 'All-on-4' is a proprietary term and must be used with appropriate attribution in commercially sensitive publications." — Editorial style guide