si-Mochi is an implant intended to fill bony voids or gaps of the skeletal system (i.e. extremities, pelvis). These osseous defects may be surgically created or the result of traumatic injury to the bone and are not intrinsic to the stability of the bony structure. si-Mochi resorbs and is replaced with bone during the healing process.
Device Story
si-Mochi is a bone void filler consisting of multi-porous bi-phase calcium phosphate ceramic granules (80% hydroxylapatite, 20% beta-tricalcium phosphate) with trace silicate, suspended in an aqueous Kolliphor polymer carrier gel. The granules feature interconnected macropores (100µm–1mm), midipores (10–100µm), and microspaces (1–10µm). Supplied in sterile applicators, the device is used by surgeons in an operating theater to fill osseous defects. Upon implantation, the porous structure acts as a scaffold, encouraging host bone formation and capillary ingrowth; the material undergoes physiologically-mediated resorption and is replaced by natural bone. The 33% Kolliphor gel provides necessary viscosity for handling at room temperature. The device does not set in-situ and contains no antibiotics.
Clinical Evidence
No human clinical data provided. Evidence consists of non-clinical bench testing (biocompatibility, pyrogenicity, endotoxin, shelf-life, packaging) and an animal study. The animal study used a rabbit critical size defect in the distal femora to compare si-Mochi against Actifuse ABX. Results indicated no statistically significant difference in the percentage of new bone formation between the subject and predicate devices at all post-implantation time points.
Technological Characteristics
Materials: Bi-phase calcium phosphate ceramic (80% hydroxylapatite, 20% beta-tricalcium phosphate) with trace silicate; Kolliphor polymer carrier gel. Structure: Multi-porous granules (1-2mm) with interconnected macropores, midipores, and microspaces. Form factor: Granules in aqueous gel, supplied in sterile applicators. Sterilization: Sterile. Energy source: None (passive implant).
Indications for Use
Indicated for filling bony voids or gaps in the skeletal system (extremities, pelvis) caused by surgical creation or traumatic injury, where the defect is not intrinsic to the stability of the bony structure.
Regulatory Classification
Identification
A resorbable calcium salt bone void filler device is a resorbable implant intended to fill bony voids or gaps of the extremities, spine, and pelvis that are caused by trauma or surgery and are not intrinsic to the stability of the bony structure.
Special Controls
*Classification.* Class II (special controls). The special control for this device is the FDA guidance document entitled “Class II Special Controls Guidance: Resorbable Calcium Salt Bone Void Filler Device; Guidance for Industry and FDA.” See § 888.1(e) of this chapter for the availability of this guidance.
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April 21, 2021
Image /page/0/Picture/1 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.
Biostone Limited Wei-Jen Lo, Ph.D. Chief Scientific Officer BioCity, Pennyfoot Street Nottingham, Notts NG1 1GF United Kingdom
## Re: K202639
Trade/Device Name: si-Mochi Regulation Number: 21 CFR 888.3045 Regulation Name: Resorbable Calcium Salt Bone Void Filler Device Regulatory Class: Class II Product Code: MQV Dated: March 16, 2021 Received: March 29, 2021
Dear Dr. Lo:
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/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.
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
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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/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-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 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 https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.
For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/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-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely,
for
Laura C. Rose, Ph.D. Assistant Director DHT6C: Division of Restorative, Repair and Trauma Devices OHT6: Office of Orthopedic Devices Office of Product Evaluation and Quality Center for Devices and Radiological Health
Enclosure
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# Indications for Use
Form Approved: OMB No. 0910-0120 Expiration Date: 06/30/2023 See PRA Statement below.
#### 510(k) Number (if known) K202639
Device Name
si-Mochi
Indications for Use (Describe)
si-Mochi is an implant intended to fill bony voids or gaps of the skeletal system (i.e.extremities, pelvis). These osseous defects may be surgically created or the result of traumatic injury to the bone and are not intrinsic to the stability of the bony structure. si-Mochi resorbs and is replaced with bone during the healing process.
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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| Submitter<br>Telephone<br>Facsimile<br>Contact Person | Biostone Limited<br>BioCity<br>Pennyfoot Street<br>Nottingham<br>NG1 1GF<br>United Kingdom<br>011 44 7906 001281<br>Wei-Jen Lo PhD |
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| Date Prepared<br>Trade Name | 21/ July/ 2019<br>si-Mochi |
| Common Name | Resorbable calcium salt bone void filler device |
| Classification | Resorbable calcium salt bone void filler devices have<br>been classified by the Orthopedics Device Panel as<br>Class II Special Controls per 21 CFR 888.3045.<br>Product code: MQV |
| Predicate Devices | TriPore® K070132, Actifuse ABX™ K082575 |
| Device Description | si-Mochi contains a multi porous bi-phase Calaium<br>Phosphate ceramic granules, 1~2mm, suspended in an<br>aqueous polymer carrier gel. The chemical composition of<br>the multi-porous ceramic granules is trace silicate induced<br>bi-phase calcium phosphate ceramic which has 80%<br>hydroxylapatite $Ca_5(PO_4)_3(OH)$ and 20% $β$ -tricalcium<br>phosphate $Ca_3(PO_4)_2$ , similar levels to those identified in<br>naturally-growing bone.<br>Its porous structure comprising three types of porosities<br>which are interconnected: macropores (100µm~1mm),<br>midipores (10~100 µm) and microspaces (1~10 µm).<br>Calcium phosphate bone graft substitutes have been<br>the topic of extensive clinical studies for several decades.<br>Biocompatibility is addressed in the non-clinical testing<br>section below. The interconnected macro-, midi- and<br>micro- porous structure encourages the rapid formation of<br>host bone and the growth of capillary blood vessels<br>throughout the network of interconnecting pores. After<br>implantation, si-Mochi undergoes physiologically-<br>mediated resorption and is replaced by natural bone. |
| | The resorption of the Ca/P porous ceramic granules<br>were controlled by the host nature bone remodelling<br>process due to the proliferated osteocytes formation<br>within the microporous structure of the ceramic<br>granules. The resorption is not controlled by its chemical<br>composition. si-Mochi is supplied in three different types<br>of sterile applicator. si-Mochi does not set in-situ<br>following implantation. si-Mochi does not contain<br>antibiotics. |
| Intended Use | si-Mochi is an implant intended to fill bony voids or<br>gaps of the skeletal system (i.e. extremities, pelvis).<br>These osseous defects may be surgically created or<br>the result of traumatic injury to the bone and are not<br>intrinsic to the stability of the bony structure. si-Mochi<br>resorbs and is replaced with bone during the healing<br>process. |
| Technical Characteristics<br>and Substantial<br>Equivalence | si-Mochi and the predicate device, Actifuse ABX share<br>similar characteristics in that they are all calcium salt<br>bone void fillers covered by 'Class II Special Controls<br>Guidance Document: Resorbable Calcium Salt Bone<br>Void Filler Device" (FDA Guidance Document 855,<br>dated June 2, 2003).<br>Both si-Mochi and Actifuse ABX are packed in different<br>type of applicator for different clinic application. Both<br>have the multi-porous Ca/P ceramic granules with<br>added trace silicate, 1~2mm, suspended in the same<br>chemical composition of synthetic aqueous binding gel.<br>The multi-porous ceramic granules in si-Mochi are near<br>identical to TriPore SBG. They share the same chemical<br>composition but the multiparous Ca/P ceramic granules<br>had added additional trace silicate. They have the same<br>multi-porous structure and their manufacturing process<br>and annealing profile are exactly the same. |
| Determination of<br>substantial equivalence | Biostone has determined that si-Mochi is substantially<br>equivalent to the predicate devices on the basis of |
| (non-clinical data) | chemical composition tests on all three devices as prescribed in the<br>'Class II Special Controls Guidance Document' referenced above.<br>Secondly, si-Mochi itself complies with the requirements of the Special<br>Controls Document referred to above. The non-clinical data also included<br>biocompatibility, pyrogenicity testing and endotoxin monitoring, shelf-life a<br>packaging validation. |
| Determination of<br>substantial<br>equivalence<br>(animal studies) | Animal study, rabbit critical size defect in the distal femora model,<br>making direct comparison against the predicate device, Actifuse ABX.<br>However, the percentage of new bone formations were not statistically<br>significant difference in animal model at all time points post-implantation<br>between si-Mochi and the predicate device. |
| Technical<br>Characteristics<br>Difference | si-Mochi and Actifuse ABX<br>1) The first is the chemical composition, where the calcium phosphate<br>granules in Actifuse ABX is pure hydroxylapatite with 0.8% Silicate. T<br>calcium phosphate granules in si-Mochi comes as bi-phase calcium<br>phosphate comprised of 20% beta tri-calcium phosphate and 80%<br>hydroxylapatite with 0.8% silicate. The differences in the chemical<br>composition of the porous calcium phosphate ceramic granules do not<br>affect the safety or effectiveness of si-Mochi, since all materials are<br>resorbable and provide the same function.<br>2) The second is the viscosity of the Kolliphor gel in both si-Mochi and<br>Actifuse ABX. The composition of Kolliphor gel in the Actifuse ABX is a<br>20%, and the viscosity will increase when the temperature raised to<br>human body temperature at 37°C. However, it was found that the low<br>viscosity gel is not sufficient to hold the granules together during the<br>lower operation theater temperature. Therefore, the composition of the<br>Kolliphor gel was increased to 33% to construct si-Mochi, for si-Mochi<br>function normally in operation theater condition. The Kolliphor gel is<br>bioinert and will not impede the function of the porous calcium<br>phosphate ceramic granules as the bone ingrowth scaffold.<br>si-Mochi and Tripore<br>The only difference is that the porous Ca/P ceramic granules contain<br>additional 0.8% of Silica in its chemical composition, the same as the othe<br>predicate device Actifuse ABX. However, the added Silica shall not affect<br>clinical performance. Since the osteointegration thesis of the porous cerar<br>granules and TriPore® are precisely the same.<br>These differences do not raise new issues of safety. |
| Conclusions | Therefore, Biostone concludes that the non clinical and animal studios |
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| Conclusions | Therefore, Biostone concludes that the non-clinical and animal studies<br>discussed above demonstrate that si-Mochi performs as well the predicate<br>device. |
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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.
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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.
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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.