PreXion 3D Excelsior is intended to produce two dimensional digital panoramic and cephalometric images, and three dimensional digital X-ray images of the dental (oral), maxillofacial, and ENT (Ear, Nose and Throat) region at the direction of healthcare professionals as diagnostic support for adult and pediatric patients. Cephalometric imaging also includes the hand wrist to obtain carpus images for growth and maturity assessment.
Device Story
PreXion 3D Excelsior is a dental cone-beam computed tomography (CBCT) system; captures X-ray data via flat panel detector; processes data on console software to reconstruct 2D panoramic, cephalometric, and 3D images. Operated by healthcare professionals in clinical settings. New features include CT-panoramic mode (reconstructs panoramic images from CT raw data) and airway measurement function (color-codes airway inner walls; calculates volume/cross-sectional area). Output viewed on console for diagnostic support; aids clinical decision-making in dental/maxillofacial/ENT treatment planning.
Clinical Evidence
Bench testing only. Performance verified through conformance to recognized standards (ANSI/AAMI ES60601-1, IEC 60601-1-2/3/6, IEC 62366, IEC 62304, IEC 60601-2-63, IEC 61223-3-4/5, IEC 60825-1, ISO 14971, ISO 10993-1/5/10, NEMA PS 3.1-3.20). 3D imaging performance assessed via MTF in x, y, and z orientations. Software verified and validated via bench tests and user evaluations.
Indicated for adult and pediatric patients requiring 2D digital panoramic, cephalometric, or 3D digital X-ray imaging of dental, maxillofacial, and ENT regions. Cephalometric imaging includes hand/wrist carpus images for growth/maturity assessment.
Regulatory Classification
Identification
A computed tomography x-ray system is a diagnostic x-ray system intended to produce cross-sectional images of the body by computer reconstruction of x-ray transmission data from the same axial plane taken at different angles. This generic type of device may include signal analysis and display equipment, patient and equipment supports, component parts, and accessories.
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Image /page/0/Picture/0 description: The image contains the logo of the U.S. Food and Drug Administration (FDA). On the left is the Department of Health & Human Services logo. To the right of that is the FDA logo, which is a blue square with the letters "FDA" in white. To the right of the blue square is the text "U.S. FOOD & DRUG ADMINISTRATION" in blue.
August 17, 2018
PreXion Corporation % Mr. Katsumi Hayashi Director, Quality Assurance and Regulatory Division 1-14-1 Kandasuda-cho, Chiyoda-ku, Tokyo 101-0041 JAPAN
Re: K181983
Trade/Device Name: PreXion 3D Excelsior Regulation Number: 21 CFR 892.1750 Regulation Name: Computed tomography x-ray system Regulatory Class: II Product Code: OAS Dated: July 23, 2018 Received: July 25, 2018
Dear Mr. Hayashi:
We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food. Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmp/pmn.cfm identifies combination product submissions. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.
If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.
Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal
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statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/CombinationProducts/GuidanceRegulatoryInformation/ucm597488.htm); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm.
For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/) and CDRH Learn (http://www.fda.gov/Training/CDRHLearn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (http://www.fda.gov/DICE) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely.
Hsl 2. Nils
Robert Ochs, Ph.D. Director Division of Radiological Health Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health
Enclosure
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#### DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration
# Indications for Use
Form Approved: OMB No. 0910-0120 Expiration Date: 06/30/2020 See PRA Statement below.
510(k) Number (if known)
K181983
Device Name PreXion 3D Excelsior
#### Indications for Use (Describe)
PreXion3D Excelsior is intended to produce two dimensional digital panoramic and cephalometric images, and three dimensional digital X-ray images of the dental (oral), maxillofacial, and ENT (Ear, Nose and Throat) region at the direction of healthcare professionals as diagnostic support for adult and pediatric patients. Cephalometric imaging also includes the hand wrist to obtain carpus images for growth and maturity assessment.
(Note: We have added technical term "dental(oral)" to clarify Indications for Use. We believe that is same definition of Indications for Use between predicate device and subject device.)
Type of Use (Select one or both, as applicable)
> Prescription Use (Part 21 CFR 801 Subpart D)
Over-The-Counter Use (21 CFR 801 Subpart C)
#### CONTINUE ON A SEPARATE PAGE IF NEEDED.
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FORM FDA 3881 (7/17)
PSC Publishing Services (301) 443-6740 DF
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# 510(k) Summary
This summary of 510(k) safety and effectiveness information is submitted in accordance with the requirements of the Safe Medical Devices Act of 1990 and 21 CFR 807.92.
510(k) Number:
# 6.1 Applicant Information
| Date Prepared: | July 23th, 2018 |
|---------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Company Name and Address: | PreXion Corporation<br>1-14-1 Kandasuda-cho, Chiyoda-ku<br>Tokyo, 101-0041<br>Japan |
| Contact Person: | Mr. Katsumi Hayashi<br>Director, Quality Assurance and Regulatory Division<br>Phone: +81-3-5297-7551<br>FAX: +81-3-5297-7552<br>Email: hayashi@prexion.co.jp |
## 6.2 Device Information
| Type of 510(k) Submission | Special |
|---------------------------|--------------------------------------|
| Device Type: | Dental Cone-beam Computed Tomography |
| Regulation Description: | Computed Tomography X-Ray System |
| Review Panel: | Radiology |
| Regulation Number: | 21 CFR 892.1750 |
| Product Code: | OAS |
| Device Class: | II |
| Device Name: | PreXion3D Excelsior |
## 6.3 Predicate Device Information
The legally marketed devices to which substantial equivalence is being claimed are:
| 510(k) Number: | K173878 |
|--------------------|----------------------|
| Applicant: | PreXion Corporation |
| Device Name: | PreXion 3D Excelsior |
| Regulation Number: | 21 CFR 892.1750 |
| Product Code: | OAS |
| Device Class: | II |
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## 6.4 Device Description
PreXion 3D Excelsior consists of a scanner, which is used for generating X-ray and detecting image data, and a Console, which is used for operating the scanner and managing the data. The scan data acquired by the scanner will be transferred to the Console. PreXion3D Excelsior Image Analysis System will then perform the image analysis (2D/3D) or image edition (creating cross-section diagram, etc.), and output the image to a printer.
During scanning, X-rays are generated from the x-ray tube head mounted in the arm of the scanner and the x-rays passing through a patient are then detected by the flat panel detector of the scanner under the control of the firmware inside and the console software installed on the qualified Computer. The detected x-ray absorption data is processed by the console software to reconstruct the diagnostic images. The PreXion3D Excelsior has three operation modes, CT scan, Panoramic scan and Cephalometric exposure.
## Summary of predicate device modifications
Predicate device has Panoramic scan mode, but Subject device is added CT-panoramic mode besides Panoramic scan mode. CT-panoramic mode is a function for CT imaging in which a panoramic image is produced by performing panoramic image reconstruction using the raw-data from CT scan. The user can observe CT image and CT-panoramic image at the same time.
Furthermore, Subject device is added Airway measurement function, which gives inner wall of airway distinquish color, and it calculates volume and cross section area.
## 6.5 Intended Use/Indications for Use
PreXion 3D Excelsior is intended to produce two dimensional digital panoramic and cephalometric images, and three dimensional digital x-ray images of the dental(oral), maxillofacial, and ENT (Ear, Nose and Throat) region at the direction of healthcare professionals as diagnostic support for adult and pediatric patients.
Cephalometric imaging also includes the hand and wrist to obtain carpus images for growth and maturity assessment.
## 6.6 Comparison to the Predicate Device
The subject device compares to the legally marketed devices as follows:
| Device | Predicate Device | Modified Device | |
|--------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------|
| | PreXion3D Excelsior (K17387) | PreXion3D Excelsior | |
| Intended<br>Use/Indications for Use | PreXion3D Excelsior is intended<br>to produce two dimensional<br>digital panoramic and<br>cephalometric images, and three<br>dimensional digital x-ray images<br>of the maxillofacial, and ENT<br>(Ear, Nose and Throat) region at<br>the direction of healthcare<br>professionals as diagnostic<br>support for adult and pediatric<br>patients. | PreXion3D Excelsior is intended to<br>produce two dimensional digital<br>panoramic and cephalometric<br>images, and three dimensional digital<br>x-ray images of the dental(oral),<br>maxillofacial, and ENT (Ear, Nose<br>and Throat) region at the direction of<br>healthcare professionals as<br>diagnostic support for adult and<br>pediatric patients.<br>Cephalometric imaging also includes | |
| | | | |
| | | Cephalometric imaging also<br>includes the hand and wrist to<br>obtain carpus images for growth<br>and maturity assessment | the hand and wrist to obtain carpus<br>images for growth and maturity<br>assessment |
| X-ray<br>Generation<br>Device | Tube<br>Voltage | 60-110KV | 60-110KV |
| | Pulse<br>Exposure<br>function | Yes | Yes |
| | Tube<br>Current | 1-6mA | 1-6mA |
| | Focal<br>Spot Size | 0.3mm | 0.3mm |
| X-ray<br>Image<br>Capturing<br>Device | Detector | 125μm x 125μm, 125μm<br>x 250μm (CT)<br>125μm x 125μm (Panoramic)<br>140 μm x 140μm (Ceph) | 125μm x 125μm, 125μm<br>x 250μm (CT)<br>125μm x 125μm (Panoramic)<br>140 μm x 140μm (Ceph) |
| | Pixel<br>Number | 1280x1024 (CT)<br>128x1280 (Panoramic)<br>2112x1754 (Cephalometric) | 1280x1024 (CT)<br>128x1280 (Panoramic)<br>2112x1754 (Cephalometric) |
| | Size of<br>Area<br>Receiving<br>X-ray | 160mm x 128mm (CT)<br>160mm x 12.5mm (Panoramic)<br>295.68 x 245.56mm (Ceph) | 160mm x 128mm (CT)<br>160mm x 12.5mm (Panoramic)<br>295.68 x 245.56mm (Ceph) |
| | Number of<br>Bits | 16bits (CT, Panorama)<br>14bits (Ceph) | 16bits (CT, Panorama)<br>14bits (Ceph) |
| Scanner | SID/SOD | 700mm/ 470mm (CT,Panoramic)<br>1735mm / 1500mm (Ceph) | 700mm/ 470mm (CT, Panoramic)<br>1735mm / 1500mm (Ceph) |
| | Dimension<br>(WxDxH) | 930 mm x 1230 mm x<br>2220 mm (CT, Panoramic)<br>1816 mm x 1230 mm x<br>2220 mm (with Ceph) | 930 mm x 1230 mm x<br>2220 mm (CT, Panoramic)<br>1816 mm x 1230 mm x<br>2220 mm (with Ceph) |
| | Weight | 165 kg (CT, Panoramic)<br>200kg (Ceph) | 165 kg (CT, Panoramic)<br>200kg (Ceph) |
| Imaging Mode | | CT scan, Panoramic scan,<br>Cephalometric radiography | CT scan, Panoramic scan,<br>Cephalometric radiography |
| Panoramic Scan<br>Performance (Scan<br>Time) | 8-16sec | 8-16sec | |
| Cephalometric<br>Radiography (Scan<br>Time) | 0.5-0.8 sec | 0.5-0.8 sec | |
| Viewer Software (Image<br>Analysis System<br>Software) | Display High-resolution 2D and<br>3D Images Function | Display High-resolution 2D and 3D<br>Images Function | |
| | Image Processing Function | Image Processing Function | |
| | Image Operation Function | Image Operation Function<br>Including Airway measurement | |
| | Output Function | Output Function | |
| Console Software<br>System Settings | CT Scan | CT Scan<br>including CT-Panoramic mode | |
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Modified device is added CT-Panoramic mode and Airway measurement function.
CT-panoramic mode is a function for CT imaging in which a panoramic image is produced by performing panoramic image reconstruction using the raw-data from CT scan. The user can observe CT image and CT-panoramic image at the same time.
Airway measurement function gives inner wall of airway distinguish color, and it calculates volume and cross section area.
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# 6.7 Non-Clinical Performance Data
The subject device has demonstrated conformance to non-clinical performance requirements through evaluation and testing in accordance with the following harmonized standards:
ANSI/AAMI ES60601-1 IEC 60601-1-2 IEC 60601-1-3 IEC 60601-1-6 IEC 62366 IEC 62304 IEC 60601-2-63 IEC 61223-3-4 IEC 61223-3-5 IEC 60825-1 ISO 14971 NEMA PS 3.1 - 3.20 ISO 10993-1 ISO 10993-5 ISO 10993-10
In addition to the conformance with the above recognized standards, the following testing and nonclinical considerations were preformed:
- . Testing for 3D imaging performance to assess MTF for three image orientations (x, y, z) for the applicable 3D modes of device operation.
- . Non-clinical considerations according to FDA Guidance "Guidance for the Submission of 510(k)'s for Solid State X-ray Imaging Devices"
Results of all non-clinical testing and non-clinical considerations support the safety and effectiveness of the subject device.
## 6.8 Brief description of software quality activities
Software quality activities for subject device is according to above standards. Based on risk management and usability evaluation, the software is verified and validated including bench tests and user evaluations. Via these processes, software quality activities for subject device comply with software moderate level concern.
## 6.9 Conclusions
The subject device clarified the Intended Use/Indications for Use, but both Intended Use/Indications for Use are same meaning between predicate and subject devices. In Viewer Software, the subject device has a different function from those of the predicate device. But, this is just additional supplemental function of the image processing functions. In Console Software, the subject device has different function from those of the predicate device. But, this is just additional supplemental function of the CT Scan mode.
Based on the above information and all data provided in this submission, the comparison of Intended Uses/Indications for Use and technological characteristics that the subject device is substantially equivalent to the predicate device identified in this submission.
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Two short videos show you everything — or skip straight to the written tutorial if you'd rather read. You can reopen this any time from the Tutorial button in the top bar.
Part 1 — Search, results, and everyday workflows 16 min
Part 2 — Embeddings: the galaxy map 3 min
1. Search: exact and fuzzy
Type a phrase like "coronary artery calcification" into the search box. You get two kinds of results. Exact results match the literal phrase — prefix searches work ("coronary artery calcificati") but suffix searches do not. Fuzzy results match on the meaning and intent of your phrase rather than the exact words, and are sorted by relevance score. Hover over the Exact or Fuzzy badge on any row to see exactly why it matched.
Use the checkboxes above the results to narrow: SaMD keeps only software-only devices, AI / ML keeps only devices with AI.
Exact vs. fuzzy search: what's the difference?
Exact matches on the literal phrase (prefix search works, suffix does not). Fuzzy matches on the meaning and intent of the phrase rather than the exact words. Hover over the badge on any row to see why it matched.
You search "coronary artery calcification" and want only software devices with AI. What two filters do you apply?
Narrow by SaMD (software-only devices), then narrow by AI/ML (devices with AI).
2. The results table
Scroll right in the results table. The intended use is extracted for you — no need to open the PDF. The device story gives a high-level snapshot of what the device does and how it's used. The AI Performance sub-table shows each output name, acceptance criteria, observed values, and development/test dataset descriptions — the same format Innolitics uses for regulatory strategy outputs, and the fastest high-level fingerprint of an AI device. It is AI-generated but has been very reliable in practice.
Where do you find a device's intended use without opening the PDF?
Scroll right in the search results table. The intended use column is extracted for you; no need to dig into the 510(k) summary PDF.
What does the AI Performance sub-table show, and why is it useful?
Output name, acceptance criteria, observed values, development dataset description, and test dataset description. It's the same format we use for regulatory strategy output and Fast 510(k) input, and the fastest high-level fingerprint of an AI device. AI-generated but reliable in practice.
3. Judging fuzzy relevance
Fuzzy results trail off in relevance as you scroll. Use three signals to decide how far down to go: the fuzzy badge explanations, the intended use column, and whether your target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, you're past the relevant zone. A top hit with a low score (~0.4) and a stretched explanation is a hint the closest predicates are far away — the project may be headed for De Novo. Note the fuzzy search is a pattern match: it doesn't handle negation ("not") well, and hardware devices can appear — filter by SaMD/AI ML to cut them.
How do you judge how far down fuzzy search results to go?
Use the relevancy signals: the fuzzy badge explanations, the intended use column, and whether the target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, results are trailing off in relevancy.
4. Device detail page: chat and citations
Click a device name to open its detail page: device facts on the left, a chat window on the right. Ask something like "Describe the training data". The answer carries little citation bubbles — click one to jump to the highlighted passage in the source PDF, so you can verify every AI answer against the document. There's also a Download PDF button for sharing.
How do you verify an AI chat answer on the device detail page?
Click the citation bubbles to jump to the relevant highlight in the source document.
Reading rule for every project: how many summaries do you read in full?
At least the three most relevant 510(k) or De Novo summaries, in full. After that, use targeted chat questions to confirm your memory quickly. The tool supports this professional habit — it doesn't replace it.
5. Side-by-side comparison
Select multiple rows in the results table (aim for under ~10), then open the PDF Viewer tab. Ask one question — it goes to all selected devices in parallel, each with citations. This is the fastest way to compare and contrast devices: training data, PCCP scope, how they handled adding new scanners, and so on.
What does the side-by-side PDF viewer mode do?
Select multiple devices, open the PDF viewer tab, and ask one question (e.g., "Describe the training data"). It queries all selected devices simultaneously with citations, so you can compare and contrast quickly.
6. Collections
With rows selected, go to the Collections tab and create a labeled collection (e.g., "Cobb Angle Project"). Reload that selection any time — before a client call, pull up the collection and ask questions across all of its devices at once.
How do you save a set of selected devices for later use?
Select the rows, go to the Collections tab, and create a labeled collection (e.g., "Cobb Angle Project"). You can reload the selection anytime and carry it into the PDF viewer and other tabs that support selections.
7. Product codes and the regulations tree
Click a product code in the results to jump to it in the regulations tree — identification text, sibling product codes, and devices you can open in a PDF viewer on the right. Click a regulation number to see its identification, special controls, and related product codes. You can also search by product code or regulation number at the top of the tree. Always read the special controls if any exist for your device — it broadens your search and sharpens pre-kickoff research.
What can you do from the regulations tree view?
Browse product codes and regulation numbers, read the identification text and special controls, browse sibling product codes, open device PDFs on the right, and search by product code or regulation number at the top of the tree.
8. Chart view
Click Show Chart and segment by regulation number (or product code) to see which regulations dominate your result set. Clicking a regulation takes you into the regulations tree. Great for spotting that most matches are, say, hardware laparoscopic devices — a cue to go back and filter.
How do you see which regulations dominate a search result set?
Click "Show Chart" and segment by Regulation Number. Clicking a regulation takes you to the regulations tree.
9. The predicate graph
Open the Predicates tab for a family-tree view of predicate relationships. Click a node to trace its parents and children; selections from search carry over pre-selected. Commonly predicated devices are worth reading — a lot of people predicated them for a reason. The visual lineage is also handy on client calls, e.g. to show how a predicate family evolved and justify why your predicate still holds.
In the predicate graph, why are commonly predicated devices worth reading?
A lot of people predicated them for a reason. Clicking a node traces parents and children, and selections from search carry over pre-selected.
10. Embeddings: the galaxy map
The Embeddings tab plots every matching document in a 2-D "galaxy map" where semantically similar devices cluster together. Hover or click clusters to explore, and let AI label the clusters for you. Embeddings beat product codes for grouping: two devices can carry different product codes (LLZ vs. QIH) yet do the same thing — the embedding captures the meaning of the intended use and device story. This is also exactly how retrieval-augmented generation (RAG) works under the hood, and it makes a great visual on client calls.
Try it yourself
Head to the search page and work through a few of these AI/ML fuzzy searches to build intuition: perivascular fat on CT · aortic valve calcification opportunistic screening on noncontrast CT · breast cancer prediction on digital pathology slides · autism detection · gestational age prediction · a hearing aid that can also detect a pulse · foundation model based analysis of ECG · large language models · penetration test. Watch how the relevance scores, intended use, and AI Performance tables tell you when results stop being meaningful.