510(k) · Cleared
ClearedAir Motor (Model name: FX204 M4); Air Motor (Model name: M205)
Data to Oct 25, 2026 (FDA decisions) Oct 12, 2026 (recalls) Sep 30, 2026 (MAUDE) refreshed weekly
Nakanishi, Inc. · EFB Handpiece, Air-Powered, Dental
Cleared on Apr 25, 2024 as substantially equivalent to K143704 (W&H Dentalwerk Buermoos GmbH, 2015) and 1 other predicate after a 209-day review. Its family tree reaches back 5 generations to 1998.
- Decided
- Apr 25, 2024
- Review
- 209 days
- Class
- Class I
- Product code
- EFB
- Recalls
- None
- Predicates
- 2
Its longest line of descent runs back 5 generations to K983183 (1998). 8 ancestors in all. No later device cites it as a predicate yet.
- Root · 5 generations backK983183 Gyro Long-Life,Black Pearl Eco, Ondine &Croma, Prestige, Bora…Bien Air USA, Inc. · 1998
- 4 generations backK031145 Estylus Electric Motor SystemDentsply Intl. · 2003
- 3 generations backK072989 Axis SystemDentsply Intl., Inc. · 2008
- 2 generations backK143704 Advanced Air SystemW&H Dentalwerk Buermoos GmbH · 2015
- 1 generation backK162926 Air-Powered Handpieces and Handpiece AttachmentsW&H Dentalwerk Burmoos GmbH · 2017
- This deviceK233308 Air Motor (Model name: FX204 M4); Air Motor (Model name: M205)Nakanishi, Inc. · 2024
View FIG. 1 as a table
Line of descent and top descendants
| Generation | Number | Device | Applicant | Decided | Recalls |
|---|---|---|---|---|---|
| −5 | K983183 | Gyro Long-Life,Black Pearl Eco, Ondine &Croma, Prestige, Bora, Aquilon… | Bien Air USA, Inc. | 1998 | — |
| −4 | K031145 | Estylus Electric Motor System | Dentsply Intl. | 2003 | — |
| −3 | K072989 | Axis System | Dentsply Intl., Inc. | 2008 | — |
| −2 | K143704 | Advanced Air System | W&H Dentalwerk Buermoos GmbH | 2015 | — |
| −1 | K162926 | Air-Powered Handpieces and Handpiece Attachments | W&H Dentalwerk Burmoos GmbH | 2017 | — |
| 0 (this device) | K233308 | Air Motor (Model name: FX204 M4); Air Motor (Model name: M205) | Nakanishi, Inc. | 2024 | — |
Other ancestors by year cleared
| Year cleared | Devices | With a Class I recall |
|---|---|---|
| 2001 | 2 | 0 |
| 2007 | 1 | 0 |
Sources: FDA 510(k) database (decision fields), the FDA summary (predicates and indications), FDA recall and enforcement reports, and MAUDE; processed by 510(k) Report. Verify on FDA.gov · Methodology and accuracy.
Planning a device in EFB? A 510(k) Report weighs predicate choices, recall history and review times for a new device like this one.
Top candidate predicates for a new EFB device
- #1 K262144 DIAMED Handpiece;DIAMED Airmotor;DIAMED…score 13.3 · 5 generations · no Class I recall
- #2 Held for the reportin the report
- #3 Held for the reportin the report
What was it cleared against? (2)
Devices the submitter claimed this one is substantially equivalent to (*), and reference devices cited for a specific test or feature (†), as written in the FDA summary.
| Type | Number | Device | Decided |
|---|---|---|---|
| * | K143704 | Advanced Air SystemSummary page 5…assification Name: Handpiece, Air-Powered, Dental Regulation Number: 872.4200 Device Class: I Product Codes: EFB Legally Marketed Predicate Devices Predicate Device #: K143704 Predicate Trade Name: Advanced Air System Product Code: EFB Reference Device #: K162926 Predicate Trade Name: W&H Air-Powered Ha… | 2015 |
| * | K162926 | Air-Powered Handpieces and Handpiece AttachmentsSummary page 5…ss: I Product Codes: EFB Legally Marketed Predicate Devices Predicate Device #: K143704 Predicate Trade Name: Advanced Air System Product Code: EFB Reference Device #: K162926 Predicate Trade Name: W&H Air-Powered Handpieces And Handpiece Attachments Product Code: EFB Device Description Summary The air… | 2017 |
What descends from it?
No later submission names this one as a predicate yet.
Has anything in its family been recalled? (0 Class I)
No FDA recall names this device.
No ancestor or descendant has a Class I recall.
What does this lineage say?
- The line of descent spans 26 years and passes through 6 companies; a new generation was cleared every 4.6 years on median.
- None of the 8 ancestors has a recall.
- 1 other device also cites its predicate K143704.
How does its category compare?
All EFB devicesEFB Handpiece, Air-Powered, Dental: FDA decisions, review times, recalls and adverse event reports over 20 years. 2024, this device’s year, is highlighted.
FDA decisions per year · EFB
1in 2025
2026 to Oct 25, outlined.
Median 510(k) review, days · EFB
209in 2024
Receipt to decision; years with fewer than 3 clearances left blank.
Recalls per year · EFB
No recall names EFB since 2007.
Adverse event reports per year · EFB
83in 2025
MAUDE reports naming product code EFB, not matched to any one device; reports are not rates.
View these four charts as a table
| Year | Decisions | Median 510(k) review, days | Recalls (Class I) | MAUDE reports |
|---|---|---|---|---|
| 2007 | 12 | 61 | 0 | 13 |
| 2008 | 7 | 97 | 0 | 19 |
| 2009 | 11 | 120 | 0 | 40 |
| 2010 | 8 | 116 | 0 | 78 |
| 2011 | 4 | 168 | 0 | 96 |
| 2012 | 8 | 130 | 0 | 97 |
| 2013 | 3 | 207 | 0 | 61 |
| 2014 | 7 | 200 | 0 | 73 |
| 2015 | 7 | 296 | 0 | 87 |
| 2016 | 3 | 205 | 0 | 122 |
| 2017 | 7 | 246 | 0 | 153 |
| 2018 | 3 | 210 | 0 | 81 |
| 2019 | 3 | 348 | 0 | 117 |
| 2020 | 5 | 259 | 0 | 94 |
| 2021 | 2 | — | 0 | 123 |
| 2022 | 5 | 430 | 0 | 157 |
| 2023 | 4 | 158 | 0 | 116 |
| 2024 | 5 | 209 | 0 | 104 |
| 2025 | 1 | — | 0 | 83 |
| 2026 | 4 | 252 | 0 | — |
What is it indicated for?
Air Motor is intended for the following application(s): Driving the handpiece for the tooth restoration, prophylaxis, and root canal preparation.
Indications for use as stated in the FDA summary.
https://510kreport.com/device/K233308 · printed Nov 3, 2026
Cite this page
510(k) Report. “K233308: Air Motor (Model name: FX204 M4); Air Motor (Model name: M205).” Lineage record from FDA 510(k) data and the FDA summary. Updated Nov 3, 2026. Accessed Nov 3, 2026. https://510kreport.com/device/K233308
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Record history
- FDA decision record loaded May 2, 2026
- Summary read Oct 13, 2026 (extraction version 9eaa42aa01ed)
- Lineage and recalls computed Nov 3, 2026
- Page last updated Nov 3, 2026