(29 days)
Aurora is an intra-oral sensor used by dental professionals for the purpose of acquiring x-ray images to be used for the diagnosis of diseases of the mouth and for evaluating general dental health.
Aurora is an intraoral digital x-ray system used to acquire digital x-ray images when used with an external x-ray source. The sensor is composed of a scintillation plate that converts incident x-ray light into visible light, which is coupled to a CMOS detector via a fiber optic plate (FOP) collimator. It connects to a PC via a 2-meter cable with USB 2.0 interface. A trained dental professional (e.g. Dentist, Dental Assistant, etc.) will operate the sensor by aligning the device inside the mouth using a positioning device, such as ring and bar holder, and then using an external x-ray source (i.e. dental x-ray tube head) to expose the sensor to radiation with the oral tissue of interest between. A software package will control the acquisition of the x-ray image from the sensor itself and will interpret the data to create an image on a computer screen for the dentist to use for diagnosis. Neither the software package nor the x-ray sensor controls the x-ray generating source in any fashion. The software package used by Sodium Dental is Xray Vision® from Apteryx, Inc (K983111). The Xray Vision® software is a network-based image acquisition and management software used to acquire x-ray/camera images and store them in a patient database.
This 510(k) summary report describes the Aurora intra-oral digital x-ray sensor, which is stated to be identical in hardware and uses identical software to its predicate device, the QuickRay HD (K151926). Therefore, the performance data presented primarily focuses on demonstrating this equivalence rather than establishing new performance criteria or conducting extensive effectiveness studies.
Here's an analysis based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
Given the claim of an identical device to the predicate, the acceptance criteria and performance are inherently tied to those of the QuickRay HD. The submission does not explicitly list "acceptance criteria" but rather presents a comparison of specifications between the Aurora and the predicate device. The "reported device performance" is the statement that these specifications are identical.
| Feature Name | Acceptance Criteria (Predicate QuickRay HD K151926) | Reported Device Performance (Aurora) |
|---|---|---|
| 510(k) | K151926 | Not assigned yet (at time of submission) |
| Applicant/510(k) owner | Denterprise International, Inc. | Sodium Systems, LLC. |
| Manufacturer - Software Component | Apteryx, Inc. | Apteryx, Inc. |
| Classification & Product Code | 872.1800; MUH | 872.1800; MUH |
| Common Name | Intraoral Digital X-ray Sensor | Intraoral Digital X-ray Sensor |
| Indications for use | Radiographic examination and diagnosis of diseases of the teeth, jaw, and oral structure. | Acquisition of x-ray images to be used for the diagnosis of diseases of the mouth and for evaluating general dental health. |
| Principles of Operation | X-ray (radiation) → scintillator (convert to visible light) → fiber optic plate (filtering) → CMOS (convert to digital image) → electronics → PC (capture and display image) | X-ray (radiation) → scintillator (convert to visible light) → fiber optic plate (filtering) → CMOS (convert to digital image) → electronics → PC (capture and display image) |
| Software - Firmware | Firmware combined on sensor electronic board | Firmware combined on sensor electronic board |
| Software - Image Management | XRayVision (Apteryx, Inc.) | XRayVision (Apteryx, Inc.) |
| Sensor Technology | CMOS chip + fiber optic plate + Csl scintillator | CMOS chip + fiber optic plate + Csl scintillator |
| Matrix Dimensions (mm²) | Active area: 600 mm² (Size 1); 884 mm² (Size 2) | Active area: 600 mm² (Size 1); 884 mm² (Size 2) |
| Matrix Dimensions (pixels) | 1000 lines x 1500 lines (Size 1); 1300 lines x 1700 lines (Size 2) | 1000 lines x 1500 lines (Size 1); 1300 lines x 1700 lines (Size 2) |
| CMOS Lifespan | Min. 100,000 cycles | Min. 100,000 cycles |
| Resolution | Real ≥ 20 lp/mm | Real ≥ 20 lp/mm |
| Pixel Size | 20 x 20 μm | 20 x 20 μm |
| Grey Levels | 14 bits | 14 bits |
| Sensor Board | All control electronics integrated directly on CMOS sensor chip | All control electronics integrated directly on CMOS sensor chip |
| Sensor Shell Material | ABS with HB flammability (YK-94, UL File No. 49895) | ABS with HB flammability (YK-94, UL File No. 49895) |
| Cable Material and Design | PVC, ETFE, copper, plug connector & sensor connector, diameter ⌀ 3.7 ± 0.3 mm, length 2 meters. | PVC, ETFE, copper, plug connector & sensor connector, diameter ⌀ 3.7 ± 0.3 mm, length 2 meters. |
| Connection to Imaging Practice PC | USB 2.0 High-speed | USB 2.0 High-speed |
| Operating Temperature | 0° C to 35° C | 0° C to 35° C |
| Sensor Input Voltage and Current | 5V (via USB); 0.15 A Max | 5V (via USB); 0.15 A Max |
| Standards of Conformity | IEC 60601-1, IEC 60601-1-2, 62220-1, 60529 | IEC 60601-1, IEC 60601-1-2, 62220-1, 60529 |
Note: The "Differences" column in the original table states "None" or "N/A" for all technical specifications, and "Equivalent" for Indications for Use.
2. Sample Size Used for the Test Set and Data Provenance
The document does not explicitly state a specific "test set" sample size for a clinical performance evaluation in the traditional sense, as the primary argument is substantial equivalence to a predicate device.
- Clinical images: "Clinical images were provided" for review by a qualified practitioner. The specific number of images is not stated.
- Data Provenance: The general nature of "clinical images" and their examination by a practitioner in Clarkston, MI, suggests retrospective use of existing images, likely from the practitioner's local patient pool. The country of origin would be the USA based on the practioner's location.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications
- Number of Experts: One (1) expert.
- Qualifications: Dr. Tiffany Danyal, D.D.S., a qualified practitioner of Clarkson Village Dental, Clarkston, MI. No further details on years of experience or specialization beyond "qualified practitioner" are provided.
4. Adjudication Method for the Test Set
The document mentions that "Clinical images were examined by Dr. Tiffany Danyal... The images were determined by Dr. Danyal to be of diagnostic quality and usefulness for evaluation of all relevant oral structures." This indicates a single-reader assessment, with no explicit adjudication method stated (e.g., 2+1, 3+1).
5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was done
No. The document does not describe a Multi Reader Multi Case (MRMC) comparative effectiveness study. The submission focuses on demonstrating substantial equivalence through direct comparison of hardware and software specifications with a predicate device, along with bench testing.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
Yes, in spirit, for technical and safety aspects, but not for "diagnostic" performance as a standalone AI. The submission argues the Aurora device is identical hardware and software to the predicate. The "Performance Data" section discusses:
- Bench tests: Performed in accordance with IEC 60601-1, IEC 60601-1-2, IEC 62220-1 (which includes DQE, MTF, NNPS measurements), and IEC 60529. These are objective engineering measurements of the device's physical and imaging characteristics, which are "standalone" in nature. The graphs of DQE, MTF, and NNPS versus spatial frequency (pages 7-8) are evidence of this.
- Software Verification and Validation Testing: This also assesses the algorithm/firmware only.
However, these standalone tests are primarily to confirm the device's technical specifications and safety profile match the predicate, not to evaluate its standalone diagnostic accuracy as an AI in interpreting images. The closest to diagnostic performance is the resolution (Real ≥ 20 lp/mm) and grey levels (14 bits), which are technical specifications rather than diagnostic outcomes.
7. The Type of Ground Truth Used
- For technical specifications (e.g., resolution, DQE): The ground truth is generally derived from physical measurements and adherence to international standards like IEC 62220-1.
- For the "clinical images" review: The "ground truth" was established by the expert opinion/assessment of a single dentist, Dr. Tiffany Danyal, who determined the images were of "diagnostic quality and usefulness." This is a subjective expert assessment rather than a definitive, independently verified ground truth like pathology.
8. The Sample Size for the Training Set
Not applicable. This submission focuses on demonstrating substantial equivalence to a predicate device, which is already a cleared medical device. There is no mention of a "training set" for an AI or machine learning algorithm. The imaging software (XRayVision) is stated to be "previously cleared by the FDA". The device itself is an image acquisition sensor, not an image interpretation AI.
9. How the Ground Truth for the Training Set was Established
Not applicable. As no training set for an AI was used, no ground truth needed to be established for it.
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Image /page/0/Picture/0 description: The image contains two logos. On the left is the Department of Health & Human Services logo, which features a stylized human figure. To the right of that is the FDA logo, which is a blue square with the letters "FDA" in white, followed by the words "U.S. FOOD & DRUG ADMINISTRATION" in blue.
July 20, 2018
Sodium Systems, LLC % Brandon Bachler, Ph.D. Chief Technology Officer 1050 Highland Drive, Suite E ANN ARBOR MI 48108
Re: K181636
Trade/Device Name: Aurora Regulation Number: 21 CFR 872.1800 Regulation Name: Extraoral source x-ray system Regulatory Class: II Product Code: MUH Dated: June 18, 2018 Received: June 21, 2018
Dear Dr. Bachler:
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. 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 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); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820);
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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 medical devices and radiation-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.
Hole 2. Nild
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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Indications for Use
510(k) Number (if known) K181636
Device Name Aurora
Indications for Use (Describe)
Aurora is an intra-oral sensor used by dental professionals for the purpose of acquiring x-ray images to be used for the diagnosis of diseases of the mouth and for evaluating general dental health.
| 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) |
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510(k) Summary
Submitter
Sodium Systems, LLC 1050 Highland Drive, Ste. E Ann Arbor, MI 48108 Date: 6/5/2018
Phone: 800-821-8962 Fax: 866-611-0677 Contact Person: Brandon Bachler Contact email: brandon.bachler@sodiumdental.com
Device Name/Classification
Proprietary trade name: Aurora Common name: Intraoral digital x-ray sensor Classification name: Extraoral Source X-ray System Regulatory class: Class II Regulation number: 21 CFR 872.1800 Classification Code: MUH Submission type: 510(k) - Traditional Medical Specialty: Dental
Predicate Device
Company: Denterprise International, Inc. Device name: QuickRay HD 510(k) number: K151926 Regulation number: 21 CFR 872.1800 Regulation name: Extraoral source x-ray system Regulatory class: II Classification code: MUH Clearance date: December 14, 2015
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Product Description
Aurora is an intraoral digital x-ray system used to acquire digital x-ray images when used with an external x-ray source.
The sensor is composed of a scintillation plate that converts incident x-ray light into visible light, which is coupled to a CMOS detector via a fiber optic plate (FOP) collimator. It connects to a PC via a 2-meter cable with USB 2.0 interface. A trained dental professional (e.g. Dentist, Dental Assistant, etc.) will operate the sensor by aligning the device inside the mouth using a positioning device, such as ring and bar holder, and then using an external x-ray source (i.e. dental x-ray tube head) to expose the sensor to radiation with the oral tissue of interest between.
A software package will control the acquisition of the x-ray image from the sensor itself and will interpret the data to create an image on a computer screen for the dentist to use for diagnosis. Neither the software package nor the x-ray sensor controls the x-ray generating source in any fashion. The software package used by Sodium Dental is Xray Vision® from Apteryx, Inc (K983111). The Xray Vision® software is a network-based image acquisition and management software used to acquire x-ray/camera images and store them in a patient database.
Aurora is designed to be used at all times with a sensor barrier to prevent any direct contact with the inside of a patient's mouth, an example of which is the product from Trollhatteplast AB.: TrollBag - registration number 3004116514. When used properly with a new sensor barrier for each patient, the unit can be reused without the need to use sterilization equipment that would destroy the sensor. At no point does the sensor itself come in contact with the patient's mouth. Sodium Systems provides thorough instructions for handling and cleaning the sensor.
Indications for use
Aurora is an intra-oral x-ray sensor used by dental professionals for the purpose of acquiring xray images to be used for the diagnosis of diseases of the mouth and for evaluating general dental health.
Intended use
The Aurora sensor is recommended for use with a ring and bar style holder for alignment, although the use of such a device is not critical to the function of the sensor. The sensor comes in two sizes, Size 1 and Size 2, designed to accommodate the acquisition of images in different locations (e.g. horizontal bite wings, vertical bite wings, anterior periapical, etc.) and different patient mouth sizes.
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Comparison with Predicate Device
Aurora is an identical device to the predicate device, the QuickRay HD (K151926) by Denterprise International, Inc. The predicate device is the same hardware device from the same hardware manufacturer, Hamamatsu. The device differs from Aurora by labeling only – no functional differences between the predicate sensor and Aurora exist.
As with our device, the predicate device comes in two sizes, size 1 and size 2. In each case, the manufacturing number from Hamamatsu is identical.
A comparison table between our sensor and the predicate device is provided below, although it should be noted that since it is identical hardware from the same manufacturer, all values in the table are necessarily the same. All values provided are for size 2 sensors. Size 1 devices are also identical to all predicate values.
| Aurora sensor(subject) | QuickRay HD(predicate) | Differences | |
|---|---|---|---|
| 510(k) | Not assigned yet | K151926 | N/A |
| Applicant/510(k)owner | Sodium Systems, LLC. | DenterpriseInternational, Inc. | N/A |
| Manufacturer -Software Component | Apteryx, Inc. | Apteryx, Inc. | None |
| Classification &Product Code | 872.1800; MUH | 872.1800; MUH | None |
| Common Name | Intraoral Digital X-raySensor | Intraoral Digital X-raySensor | None |
| Indications for use | Acquisition of x-rayimages to be used forthe diagnosis ofdiseases of the mouthand for evaluatinggeneral dental health. | Radiographicexamination anddiagnosis of diseases ofthe teeth, jaw, and oralstructure. | Equivalent |
| Principles of Operation | X-ray (radiation) →scintillator (convert tovisible light) → fiberoptic plate (filtering) →CMOS (convert todigital image) →electronics → PC(capture and displayimage) | X-ray (radiation) →scintillator (convert tovisible light) → fiberoptic plate (filtering) →CMOS (convert todigital image) →electronics → PC(capture and displayimage) | None |
| Software - Firmware | Firmware combined onsensor electronic board | Firmware combined onsensor electronic board | None |
| Software - Image Management | XRayVision (Apteryx, Inc.) | XRayVision (Apteryx, Inc.) | None |
| Sensor Technology | CMOS chip + fiber optic plate + Csl scintillator | CMOS chip + fiber optic plate + Csl scintillator | None |
| Matrix Dimensions (mm²) | Active area: 600 mm² (Size 1); 884 mm² (Size 2) | Active area: 600 mm² (Size 1); 884 mm² (Size 2) | None |
| Matrix Dimensions (pixels) | 1000 lines x 1500 lines (Size 1); 1300 lines x 1700 lines (Size 2) | 1000 lines x 1500 lines (Size 1); 1300 lines x 1700 lines (Size 2) | None |
| CMOS Lifespan | Min. 100,000 cycles | Min. 100,000 cycles | None |
| Resolution | Real ≥ 20 lp/mm | Real ≥ 20 lp/mm | None |
| Pixel Size | 20 x 20 μm | 20 x 20 μm | None |
| Grey Levels | 14 bits | 14 bits | None |
| Sensor Board | All control electronics integrated directly on CMOS sensor chip | All control electronics integrated directly on CMOS sensor chip | None |
| Sensor Shell | Material is ABS and the flammability is HB if YK-94 (UL File No. 49895) | Material is ABS and the flammability is HB if YK-94 (UL File No. 49895) | None |
| Cable Material and Design | Cable consists of PVC, ETFE, copper, plug connector and sensor connector, diameter ⌀ 3.7 ± 0.3 mm and cable length 2 meters. | Cable consists of PVC, ETFE, copper, plug connector and sensor connector, diameter ⌀ 3.7 ± 0.3 mm and cable length 2 meters. | None |
| Connection to Imaging Practice PC | USB 2.0 High-speed | USB 2.0 High-speed | None |
| Operating Temperature | 0° C to 35° C | 0° C to 35° C | None |
| Sensor Input Voltage and Current | 5V (via USB connection); 0.15 A Max | 5V (via USB connection); 0.15 A Max | None |
| Standards of Conformity | IEC 60601-1 (Electrical) IEC 60601-1-2 (EMC) 62220-1 (Performance) 60529 (IP Code) | IEC 60601-1 (Electrical) IEC 60601-1-2 (EMC) 62220-1 (Performance) 60529 (IP Code) | None |
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| Input | Calculation software*1 | Output |
|---|---|---|
| MTFNNPS$\Phi$ | $DQE = \frac{MTF^2}{\Phi \cdot NNPS}$ | DQE |
*1: The calculation procedure is the same as that in IEC62220-1.
Image /page/7/Figure/2 description: The image contains two line plots that show the relationship between spatial frequency and two different metrics: DQE (Detective Quantum Efficiency) and MTF (Modulation Transfer Function). Both plots have spatial frequency on the x-axis, ranging from 0 to 25 cycles/mm. The DQE plot shows a curve that starts at approximately 0.45 and decreases to nearly 0 as spatial frequency increases, while the MTF plot starts at 1.0 and decreases to nearly 0 as spatial frequency increases.
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Image /page/8/Figure/0 description: The figure is a plot of NNPS [mm^2] vs Spatial Frequency [cycles/mm]. The x-axis is the spatial frequency, ranging from 0 to 30 cycles/mm. The y-axis is the NNPS, ranging from 1.E-08 to 1.E-04 mm^2. The plot shows a decreasing trend, with the NNPS decreasing as the spatial frequency increases.
Performance Data
Clinical images were provided; these images were not necessary to establish substantial equivalence based on the modifications to the predicate device but they provide further evidence in addition to bench testing data to show that the complete system works as intended.
Clinical images were examined by Dr. Tiffany Danyal, D.D.S., a qualified practitioner of Clarkson Village Dental, Clarkston, MI. The images were determined by Dr. Danyal to be of diagnostic quality and usefulness for evaluation of all relevant oral structures.
Biocompatibility
Because Aurora is intended to be used with a sensor barrier shield, such as the product from Dentsply, Inc.: Universal Digital Sensor Cover (SKU 550500), there is no contact between the sensor and patient. As a result, biocompatibility testing is not necessary or pertinent for this device. Nonetheless, a biomedical conformity test report is included in this submission.
Electromagnetic Compatibility and Electrical, Mechanical, and Thermal Safety
Aurora has been tested for full compliance to electrical and safety standard IEC 60601-1 -Medical electrical equipment - Part 1: General requirements for basic safety and essential performance, just as the predicate device has. Similarly, Aurora has been tested for full compliance to electrical and safety standard IEC 60601-1-2 - Medical electrical equipment - Part 1-2: General requirements for basic safety and essential performance – Collateral Standard: Electromagnetic Compatibility.
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Guidance Documents
The following device specific guidance documents were used in the development of the Aurora sensor:
-
- Guidance for the Submission of 510(k)s for Solid State Imaging Devices, issued on September 1, 2016
-
- Guidance for the Content of Premarket Submissions for Software Contained in Medical Devices, issued on May 11, 2005
- Pediatric Information for X-ray Imaging Device Premarket Notifications, issued 3. November 28, 2017
-
- Guidance for the Content of Premarket Submissions for Management of Cybersecurity in Medical Devices, issued on October 2, 2014
Software Verification and Validation Testing
The Aurora sensor contains firmware and driver software, both provided by Hamamatsu. The Aurora sensor also uses imaging software - previously cleared by the FDA - provided by Apteryx, lnc. (Xray Vision®, K983111). Firmware and driver documentation for the subject device are included in this petition, along with the 510(k) summary for the Apteryx Xray Vision® companion software. Firmware and driver software were both cleared previously with the predicate device. The previously cleared Apteryx XRay Vision Imaging Software has not been modified for use with Aurora.
Bench Testing
Bench tests were performed on the Aurora, in accordance with IEC 60601-1 (Medical electrical equipment - Part 1: General requirements for basic safety and essential performance), IEC 60601-1-2 (Medical electrical equipment – Part 1-2: General requirements for safety – Collateral standard: Electromagnetic compatibility – Requirements and tests), IEC 62220-1 (Medical Electrical Equipment – Characteristics of Digital X-ray Imaging Devices – Part 1: Determination of the Detective Quantum Efficiency) and IEC 60529 (Degrees of Protection Provided by Enclosures - IP Codes).
Conclusion
Aurora is a sensor which is identical in hardware and uses identical software to the predicate device. The only differences between our device and the predicate device are marketing in nature - the name of the sensor and branding. No new technology, safety risks, or software are introduced in our device. Therefore, we feel that the device is substantially equivalent to the predicate device.
§ 872.1800 Extraoral source x-ray system.
(a)
Identification. An extraoral source x-ray system is an AC-powered device that produces x-rays and is intended for dental radiographic examination and diagnosis of diseases of the teeth, jaw, and oral structures. The x-ray source (a tube) is located outside the mouth. This generic type of device may include patient and equipment supports and component parts.(b)
Classification. Class II.