# K022020: Justwo Model Tme-601 Root Apex Locator

- Pathway: 510(k) (Special)
- Applicant: Toei Electric Co., Ltd.
- Decided: Jul 2, 2002 after 12 days
- Product code: LQY (Locator, Root Apex)
- Device class: U
- Recalls of this device: none
- Data: FDA decisions to Oct 25, 2026; recalls to Oct 12, 2026

## Lineage
Longest line of descent: 2 generations back to K921979 (1993). 3 ancestors in all.
15 later devices descend from it; 2 cite it directly.
0 of 19 devices in its family (counting itself) have a Class I recall.

## Predicates on the family tree (from the FDA summary)
- K972407: Root Apex Locator, Toei Electric Co., Ltd. (1997) Summary page 1.

## Most influential descendants
- K032743: Apex NRG (2004), 7 descendants of its own
- K030526: Pediguard Nerve Detector System (2004), 6 descendants of its own
- K123390: Pediguard Nerve Detector System (2013), 5 descendants of its own
- K063843: Apexnrg XFR (2007), 5 descendants of its own
- K143159: Cannulated PediGuard Needle#1, Cannulated PediGuard Needle#2, Cannulated PediGuard Needle 120mm, Cannulated PediGuard Handle; PediGuard Tri Tip Ø4.0mm, PediGuard Tri Tip Ø3.2mm, PediGuard Tri Tip Ø2.5mm, PediGuard Ø2.5mm XS, PediGuard Curv, PediGuard Curv XS (2015), 4 descendants of its own

## Indications for use
Measurement of the length of the root canal for the purpose of performing root canals and related dental procedures, for use by a trained professional in general dentistry.

Source page: https://510kreport.com/device/K022020
Methodology: https://510kreport.com/methodology