Implant Stability Quotient
Also written as: ISQ — Implant Stability Quotient
A numerical scale (1–100) derived from resonance frequency analysis that quantifies the stability of a dental implant at a given time point.
Full Definition
The Implant Stability Quotient (ISQ) is a dimensionless value generated by resonance frequency analysis devices (e.g., Osstell) to express implant stability. Values typically range from 55–85 in clinically successful implants, with higher values indicating greater stiffness at the bone–implant interface. Editors will encounter ISQ values in clinical trial outcome tables, case reports, and loading protocol justifications. Because ISQ is device-specific and not a direct measure of bone density or percentage osseointegration, editors should ensure authors do not over-interpret it as an absolute biological indicator. ISQ thresholds for immediate or early loading decisions are frequently cited but lack universal consensus.
Usage
Usage note: When expanding the acronym on first use, write 'Implant Stability Quotient (ISQ)'. Do not confuse the ISQ scale with Newton-centimetre torque values; they measure different properties.
In Context
- "A baseline Implant Stability Quotient of 72 was recorded immediately after placement, rising to 79 at the eight-week review." — Clinical trial results section
- "The authors used an ISQ threshold of ≥65 as an inclusion criterion for immediate provisional loading." — Materials and methods section