Tooth Universal Numbering System
Also written as: UNS — Universal Numbering System
The American Dental Association's standardised system for identifying individual teeth using numbers 1–32 for permanent teeth and letters A–T for primary teeth.
Full Definition
The Universal Numbering System (UNS) is the tooth-identification convention mandated for use on dental insurance claim forms in the United States. Permanent teeth are numbered 1 through 32, starting at the maxillary right third molar and proceeding clockwise around the mouth. Primary (deciduous) teeth are designated by the letters A through T. Editors working on dental records, radiograph reports, treatment notes, and insurance forms must confirm that tooth references use this system consistently and correctly, as transpositions or use of alternative systems (such as the FDI two-digit system or Palmer notation) can cause claim rejection. Common editorial errors include reversing upper and lower quadrant assignments or skipping numbers when teeth are missing.
Usage
Usage note: US dental insurance forms require UNS numbering. If a document uses FDI or Palmer notation, flag for conversion before submission. Do not mix systems within a single document.
In Context
- "The operative note referenced tooth #14 (maxillary left first molar) using the Universal Numbering System as required by the carrier." — Insurance claim form / operative note
- "Editors should flag any document that uses FDI two-digit codes instead of UNS numbers on US insurance submissions." — Editorial quality-control checklist