ISO Size
Also written as: ISO — International Organization for Standardization
A standardized numerical designation for the diameter of an endodontic instrument tip, expressed in hundredths of a millimetre according to ISO 3630-1.
Full Definition
ISO size refers to the standardized tip diameter of endodontic files and pluggers, as defined by the International Organization for Standardization (ISO 3630-1). An ISO size 20 instrument, for example, has a tip diameter of 0.20 mm. The ISO color-coding system accompanies size designations (e.g., yellow for size 15, red for size 20), and editors should confirm color references match the correct numerical size. The size is written as a numeral without a leading zero in editorial convention: 'size 15', not 'size 015' or '#15' unless journal style specifies the hash symbol.
Usage
Usage note: Write as 'size 15' or 'ISO 15'; do not write '#15' unless mandated by journal style. Ensure color-code references are consistent with the correct ISO numeral.
In Context
- "Canal negotiation was initiated with an ISO size 10 stainless steel K-file under copious irrigation." — Materials and methods section
- "The master apical file was taken to ISO size 25 with a 0.06 taper." — Clinical case description