ISO 5365:2024

Overview - ISO 5365:2024 (Dentistry - Designation system for tooth developmental stages)

ISO 5365:2024 defines a compact, human‑readable designation system for tooth developmental stages using a single letter and number. The standard specifies a letter to indicate the tooth part (crown, root, apex) and a number to indicate the development stage. The coding method is intended to simplify data entry, improve consistency of radiographic staging and support interoperability across dental records, research and forensic systems.

Key topics and technical requirements

• Letter‑number code structure: letter = part of tooth (C = crown, R = root, A = apex); number = developmental stage (e.g., C0–C7, R1–R5, A1–A2).
• Defined stages and descriptors: Clause 3 provides detailed stage definitions for crown, root and apex development based on radiographic appearance (e.g., mineralisation, cusp coalescence, pulp roof outline, root length relative to crown).
• Tables and illustrative material: Annex A contains informative tables and images for multi‑rooted and single‑rooted teeth to aid stage assignment.
• Designation rules:
  • Staging is based on radiographic images and the terms in Clause 3.
  • A tooth remains at a stage until elements of the next stage appear.
  • If different roots of the same tooth are at different stages, choose the less mature (most developing) root stage for designation.
• Normative references: integrates terminology and requirements from ISO 1942 (vocabulary) and ISO 20888 (forensic oro‑dental designation); tooth numbering follows ISO 3950 as used in the document.

Practical applications

• Dental age assessment and anthropological research - standardizes stage scoring for population studies and chronological age estimation.
• Forensic odontology - consistent reporting in age estimation, missing person identification and medico‑legal casework.
• Clinical dentistry - pediatric dentistry, orthodontics and endodontics for growth monitoring and treatment timing.
• Dental informatics & EHR integration - enables interoperable coding in electronic health records, radiology information systems and research databases.
• Software & device manufacturers - supports standardized annotations in imaging software, AI models and diagnostic tools.

Who should use it

• Dentists, forensic odontologists, dental radiologists, researchers, public health professionals, EHR vendors, medical‑legal practitioners and dental imaging software developers.

Related standards

• ISO 1942 - Dentistry vocabulary
• ISO 20888 - Forensic oro‑dental data designation
• ISO 3950 - Tooth designation (tooth numbering system referenced by ISO 5365)

Using ISO 5365:2024 helps improve reproducibility, accuracy and interoperability of tooth development data across clinical, forensic and research settings.