PAI
Also written as: PAI — Periapical Index
Abbreviation for Periapical Index, a validated five-point radiographic scale for grading periapical tissue health in endodontic studies.
Full Definition
PAI is the standard abbreviation for the Periapical Index and appears frequently in endodontic research publications and outcome tables. It is an ordinal scoring system, and editors should be alert to authors reporting PAI data with means and standard deviations rather than medians and interquartile ranges. The acronym should be introduced at first use as 'Periapical Index (PAI)' and defined in any required abbreviations table. PAI is distinct from other clinical indices such as the Plaque Index or Gingival Index, and editors should ensure these are not conflated when multiple indices are reported in the same manuscript.
Usage
Usage note: Confirm PAI is not confused with other index abbreviations (PI, GI) when multiple indices are used in the same manuscript.
In Context
- "PAI scores were dichotomised into 'success' (PAI 1–2) and 'failure' (PAI 3–5) for the primary analysis." — Endodontic clinical study results
- "The abbreviations list should include PAI with its full form 'Periapical Index' and a citation to the original scale development paper." — Journal submission checklist