Once-Fil Flow

K251283 · Mediclus Co., Ltd. · EBF · Jun 6, 2025 · Dental

Device Facts

• Record ID: K251283
• Device Name: Once-Fil Flow
• Applicant: Mediclus Co., Ltd.
• Product Code: EBF · Dental
• Decision Date: Jun 6, 2025
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 872.3690
• Device Class: Class 2
• Attributes: Therapeutic

Intended Use

Temporary inlay and onlay treatments of the cavity. Sealing of openings for implant screws. Relining material for temporary crowns and bridges. Covering of the gingival margin. Fixing of resin matrix during filling placement. Block-out material for retentive ares in the dental arch, e.g. before taking impressions.

Device Story

Once-Fil Flow is a light-curing, resin-based temporary filling material; supplied in syringes with disposable tips. Used by dentists in clinical settings for interim restorations, pulp protection, and maintaining tooth position. Available in yellow (anterior esthetics) and blue (visual contrast for removal). Application involves tooth surface preparation, material placement, and light-curing; finished/polished with conventional instruments. Provides temporary coverage for cavities, implant screws, and crowns/bridges; facilitates impression taking by blocking out retentive areas. Benefits include ease of identification for removal and protection of prepared dental structures during the interim period before permanent restoration.

Clinical Evidence

Bench testing only. Performance evaluated per ISO 4049 (curing depth, water sorption/solubility, color stability, Shore D hardness) and ISO 868. Biocompatibility testing conducted per ISO 10993-1, including cytotoxicity (ISO 10993-5), irritation (ISO 10993-21), systemic toxicity (ISO 10993-11), and skin sensitization (ISO 10993-10).

Technological Characteristics

Light-curing resin material composed of Bis-GMA, UDMA, HEMA, silicone dioxide, camphorquinone, BHT, and pigment. Complies with ISO 4049 and ISO 868. Curing depth: 4.3 mm. Shore D hardness: 53. Delivered via syringe with disposable tips. Shelf-life: 3 years.

Indications for Use

Indicated for temporary dental restorations, including inlay/onlay treatments, implant screw access sealing, temporary crown/bridge relining, gingival margin covering, resin matrix fixation, and dental arch block-out for impressions. For use by licensed dentists or dental professionals.

Regulatory Classification

Identification

Tooth shade resin material is a device composed of materials such as bisphenol-A glycidyl methacrylate (Bis-GMA) intended to restore carious lesions or structural defects in teeth.

Predicate Devices

• Clip Flow by VOCO GmbH (K153493)

Submission Summary (Full Text)

{0}

FDA U.S. FOOD & DRUG ADMINISTRATION

June 6, 2025

Mediclus Co., Ltd.
Ku Da Hyeon
RA Associate
No. 1210, 134, Gongdan-ro, Heungdeok-gu
Cheongju-si, 28576
Korea, South

Re: K251283
Trade/Device Name: Once-Fil Flow
Regulation Number: 21 CFR 872.3690
Regulation Name: Tooth Shade Resin Material
Regulatory Class: Class II
Product Code: EBF
Dated: April 25, 2025
Received: April 25, 2025

Dear Ku Da Hyeon:

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 (the 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 available at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/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.

Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device"

U.S. Food & Drug Administration
10903 New Hampshire Avenue
Silver Spring, MD 20993
www.fda.gov

{1}

K251283 - Ku Da Hyeon
Page 2

(https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download).

Your device is also subject to, among other requirements, the Quality System (QS) regulation (21 CFR Part 820), which includes, but is not limited to, 21 CFR 820.30, Design controls; 21 CFR 820.90, Nonconforming product; and 21 CFR 820.100, Corrective and preventive action. Please note that regardless of whether a change requires premarket review, the QS regulation requires device manufacturers to review and approve changes to device design and production (21 CFR 820.30 and 21 CFR 820.70) and document changes and approvals in the device master record (21 CFR 820.181).

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 (reporting of medical device-related adverse events) (21 CFR Part 803) for devices or postmarketing safety reporting (21 CFR Part 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reporting-combination-products); 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 Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050.

All medical devices, including Class I and unclassified devices and combination product device constituent parts are required to be in compliance with the final Unique Device Identification System rule ("UDI Rule"). The UDI Rule requires, among other things, that a device bear a unique device identifier (UDI) on its label and package (21 CFR 801.20(a)) unless an exception or alternative applies (21 CFR 801.20(b)) and that the dates on the device label be formatted in accordance with 21 CFR 801.18. The UDI Rule (21 CFR 830.300(a) and 830.320(b)) also requires that certain information be submitted to the Global Unique Device Identification Database (GUDID) (21 CFR Part 830 Subpart E). For additional information on these requirements, please see the UDI System webpage at https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance/unique-device-identification-system-udi-system.

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-devices/medical-device-safety/medical-device-reporting-mdr-how-report-medical-device-problems.

For comprehensive regulatory information about medical devices and radiation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). 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 (https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email ([e-mail]) or phone [phone] or 301-796-7100).

{2}

K251283 - Ku Da Hyeon
Page 3

Sincerely,


Bobak
Shirmohammadi -
S

For Michael E. Adjodha, M.ChE., RAC, CQIA
Assistant Director
DHT1B: Division of Dental and
ENT Devices
OHT1: Office of Ophthalmic, Anesthesia,
Respiratory, ENT, and Dental Devices
Office of Product Evaluation and Quality
Center for Devices and Radiological Health

Enclosure

{3}

FORM FDA 3881 (6/20)
Page 1 of 1
PSC Publishing Services [phone]
EF

| DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration Indications for Use | Form Approved: OMB No. 0910-0120 Expiration Date: 06/30/2023 See PRA Statement below. |
| --- | --- |
| 510(k) Number (if known) K251283 | |
| Device Name Once-Fil Flow | |
| Indications for Use (Describe) - Temporary inlay and onlay treatments of the cavity. - Sealing of openings for implant screws. - Relining material for temporary crowns and bridges. - Covering of the gingival margin - Fixing of resin matrix during filling placement. - Block-out material for retentive ares in the dental arch, e.g. before taking impressions. | |
| 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. | |
| This section applies only to requirements of the Paperwork Reduction Act of 1995. *DO NOT SEND YOUR COMPLETED FORM TO THE PRA STAFF EMAIL ADDRESS BELOW.* | |
| The burden time for this collection of information is estimated to average 79 hours per response, including the time to review instructions, search existing data sources, gather and maintain the data needed and complete and review the collection of information. Send comments regarding this burden estimate or any other aspect of this information collection, including suggestions for reducing this burden, to: Department of Health and Human Services Food and Drug Administration Office of Chief Information Officer Paperwork Reduction Act (PRA) Staff [e-mail] | |
| "An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB number." | |

{4}

No. 1210, 134, Gongdan-ro, Heungdeok-gu, Cheongju-si, Chungcheongbuk-do, Korea
TEL [phone] FAX [phone] e-mail : [e-mail] www.mediclus.co.kr
MDclus MEDICLUS CO., LTD.

# 510(k) Summary (K251283)

This summary of 510(K) information is being submitted in accordance with requirements of 21 CFR Part 807.92.

Date: Apr 25,2025

## 1. Submitter/Contact Person

Da-Hyeon, Ku
MEDICLUS Co., Ltd.
No. 1210, 134, Gongdan-ro, Heungdeok-gu,
Cheongju-si, Chungcheongbuk-do, Republic of Korea
TEL: [phone] FAX: [phone]
Email: [e-mail]

## 2. U.S Agent

Priscilla Chung
LK Consulting Group USA, Inc.
18881 Von Karman Ave STE 160, Irvine CA 92612
Phone: [phone] Fax: [phone]
Email: [e-mail]

## 3. Device

- Trade Name: Once-Fil Flow
- Common Name: Tooth Shade Resin
- Classification Name: Tooth Shade Resin Material
- Product Code: EBF
- Classification regulation: 21 CFR 872.3690

## 4. Predicate Device:

Clip Flow by VOCO GmbH (K153493)

## 5. Description:

Once-Fil Flow is a light-curing filling material designed for temporary restorations. It serves as an interim solution before the placement of a final prosthesis, providing

510(k) summary

{5}

No. 1210, 134, Gongdan-ro, Heungdeok-gu, Cheongju-si, Chungcheongbuk-do, Korea
TEL [phone] FAX [phone] e-mail : [e-mail] www.mediclus.co.kr
MD clUS MEDICLUS CO., LTD.

functions such as pulp protection and maintaining tooth position. The material is suitable for temporary fillings in prepared cavities and inlay/onlay cases.

To accommodate different clinical needs, Once-Fil Flow is available in two shades. The Yellow shade is ideal for anterior teeth, where esthetics are a priority, while the Blue shade provides clear visual contrast, making it easier to identify and remove before permanent restoration.

The application process involves preparing the tooth surface, applying an appropriate amount of material, and light-curing it. Once cured, the material can be finished and polished using conventional instruments.

## 6. Indication for use:

- Temporary inlay and onlay treatments of the cavity
- Sealing of openings for implant screws
- Relining material for temporary crowns and bridges
- Covering of the gingival margin
- Fixing of resin matrix during filling placement
- Block-out material for retentive areas in the dental arch, e.g. before taking impressions

## 7. Basis for Substantial Equivalence

### 7.1. Comparison Chart

| | Subject Device | Predicate Device | Equivalence evaluation |
| --- | --- | --- | --- |
| Manufacturer | MEDICLUS Co., Ltd. | VOCO GmbH | - |
| Product Name | Once-Fil Flow | Clip Flow | - |
| 510k# | - | K153493 | - |
| Product Code | EBF | EBF | |
| Material | Bis-GMA
UDMA
HEMA
Silicone dioxide
Camphorquinone
2,6-Di-tert-butyl-4-methylphenol (BHT)
CoAl₂O₄ (Pigment)
Etc.. | BHT
2-hydroxyethyl methacrylate
Urethane Methacrylate
Pyrogenic silicic acids catalyst | Similar |

510(k) summary

{6}

No. 1210, 134, Gongdan-ro, Heungdeok-gu, Cheongju-si, Chungcheongbuk-do, Korea
TEL [phone] FAX [phone] e-mail : [e-mail] www.mediclus.co.kr
MDclus MEDICLUS CO., LTD.

| Curing type | | Light Curing | Light Curing | Same |
| --- | --- | --- | --- | --- |
| Indications for Use Statement | | 1) Temporary inlay and onlay treatments of the cavity.
2) Sealing of openings for implant screws.
3) Relining material for temporary crowns and bridges.
4) Covering of the gingival margin.
5) Fixing of resin matrix during filling placement.
6) Block-out material for retentive areas in the dental arch, e.g. before taking impressions. | 1) Temporary inlay and onlay treatments of the cavity.
2) Sealing of openings for implant screws.
3) Relining material for temporary crowns and bridges.
4) Covering of the gingival margin.
5) Fixing of resin matrix during filling placement.
6) Block-out material for retentive areas in the dental arch, e.g. before taking impressions. | Same |
| Intended User | | Licensed Dentist or Dental Professional | Licensed Dentist or Dental Professional | Same |
| Technological Characteristics | Standard | ISO 4049 | ISO 4049 | Similar |
| | Curing Depth | 4.3 mm | 4 mm | |
| | Water Absorption | 32 μg/mm² | | |
| | Solubility | 5 μg/mm² | 18.4 μg/mm² | |
| | Color and color stability | All samples have a matching shade guide | - | |
| | Sensitivity to ambient light | All samples are physically homogeneous | - | |
| | Shore D Hardness | Standard: ISO 868
Result: 53 | - | |
| Biocompatibility | | Biocompatible | Biocompatible | Same |
| Delivery method | | • Delivery System: Syringe
• Weight: 1.2ml
• Disposable tip | • Delivery System: Syringe
• Weight: 1.8g
• Disposable tip | Similar |
| Period of Use | | Prolonged exposure(B)
(exceed 24 hours but not 30 days) | Prolonged exposure(B)
(exceed 24 hours but not 30 days) | Same |
| Shelf-Life | | 3 years | 3 years | Same |

## 7.2. Comparison Chart

The subject device has the same indications for use and the technological characteristics as the predicate device. The minor raw materials are different between the devices but the performance and the biocompatibility test results show that it does not raise a concern in safety and effectiveness.

## 8. Non-Clinical Testing

- Performance Tests including

510(k) summary

{7}

No. 1210, 134, Gongdan-ro, Heungdeok-gu, Cheongju-si, Chungcheongbuk-do, Korea
TEL [phone] FAX [phone] e-mail : [e-mail] www.mediclus.co.kr
MDclus MEDICLUS CO., LTD.

- Appearance, Weight, Packaging, Sensitivity to Ambient Light, Curing Depth, Water Sorption/Solubility, Color and Color stability, Shore D Hardness in accordance with ISO 4049, ISO 868.

- Biocompatibility Tests
- ISO 10993-1 Biological evaluation of medical devise – Part 1: Evaluation and testing within a risk management process
- ISO 10993-5:2009, test for in vitro cytotoxicity
- ISO 10993-21:2021, Tests for irritation
- ISO 10993-11:2017, Tests for systemic toxicity
- ISO 10993-10:2021, Tests for skin sensitization

9. Conclusion

The subject device and the predicate device have the same intended use and have the same technological characteristics. Based on the similarities and the test results, we conclude that the subject device is substantially equivalent to the predicate device.

510(k) summary
4 / 4 page