(521 days)
The Micro Screw System, Micro Screw System Basic are developed and manufactured to be used as non-active bone surgery implants for the treatment of bone fractures, especially for the fixation of transplanted bone blocks during the augmentation process in the oral cavity and maxillomandibular surgical field. Note: Micro Screws are not intended to remain in the body permanently. After they have fulfilled their supportive function such as is the case after healing of a transplant, or healing of a fracture, for example, they need to be removed completely.
The Micro Screw System, Micro Screw System Basic are used for the safe fixation and stabilisation of cortical bone grafts. These systems contain osteosynthesis screws made of surgical stainless steel with diameters of 1.0 mm and 1.2 mm.
This is a 510(k) premarket notification for a medical device called the "Micro Screw System, Micro Screw System Basic". This type of submission is for demonstrating substantial equivalence to a legally marketed predicate device, rather than proving safety and effectiveness through clinical trials with specific acceptance criteria in the same way a PMA (Premarket Approval) would.
Therefore, the structure of the response will be different as the document does not contain information about a study designed to meet specific performance acceptance criteria in the typical sense for an AI/ML device. Instead, the "study" is a set of non-clinical bench tests comparing the new device to a predicate device to show equivalence.
Here's an analysis based on the provided document:
1. Table of Acceptance Criteria and Reported Device Performance
Since this is a 510(k) for a physical medical device (micro screws), the "acceptance criteria" are primarily established by recognized standards and requirements for substantial equivalence to a predicate device, rather than explicit numerical performance targets like sensitivity/specificity for an AI system. The "reported device performance" are the results of bench tests demonstrating compliance with these standards and comparability to the predicate.
| Acceptance Criteria Category (implied by standards & predicate comparison) | Reported Device Performance (Micro Screw System, Micro Screw System Basic) |
|---|---|
| Material Properties: | |
| - Standard for Wrought Stainless Steel (ASTM F138, ISO 5832-1) | Meets ASTM F138 (UNS S31673) and ISO 5832-1. Same material as predicate. |
| - Biocompatibility (ISO 10993-1, -5, ISO 7405) | Biocompatibility risk assessment conducted. Shown non-cytotoxic. Similar material/manufacturing as predicate. Safe regarding auxiliary substances. |
| Mechanical Performance (ASTM F543-17): | |
| - Torsional Properties (yield strength, max torque, breaking angle) | Higher insertion torques, higher maximal torque, comparable final ratio (~9 vs. ~10). Breaking angle equivalent to predicate. Ductility acceptable. |
| - Driving Torque | Substantially equivalent to predicate. |
| - Axial Pullout Strength | Comparable values to predicate. |
| Sterilization: | |
| - Validation according to ISO 17664, 17665-1, 11737-1/2, AAMI ST79/ST81, ISO 14937, DIN EN 868-2. | Successfully steam sterilized in 3 independent cycles following reprocessing instructions. |
| Shelf-life: | Delivered non-sterile (same as predicate). |
| Design: (Implicit comparison to predicate) | Self-tapping thread, cylindrical shank, atraumatic apex, flat drill head with square bore, smooth screw surface for simple removal. (Similar to predicate). |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size for Test Set: The document does not specify a numerical sample size for the mechanical performance tests (e.g., how many screws were tested for torsional properties). It mentions "Several performance tests have been performed."
- Data Provenance: The tests are "Non-Clinical Bench Testing" conducted by the manufacturer, Hager & Meisinger GmbH. The country of origin for the data is Germany (where the company is based), but the standards used are international (ASTM, ISO, AAMI, DIN EN). This is retrospective data, as it describes tests already performed.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
This information is not applicable in the context of this 510(k) submission for a physical device. Ground truth for mechanical properties is established through standardized physical measurements and material science, not human expert consensus.
4. Adjudication Method for the Test Set
Not applicable. Adjudication methods like 2+1 or 3+1 are used for expert consensus in clinical studies, particularly for AI/ML performance evaluation, not for physical device bench testing.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and Effect Size
Not applicable. This is not an AI/ML device, and an MRMC study is relevant for evaluating the impact of AI on human reader performance, which isn't the scope of this submission.
6. If a Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study Was Done
Not applicable. This device does not involve an algorithm.
7. The Type of Ground Truth Used
The "ground truth" for this device's evaluation is primarily:
- Physical Measurements: Directly measured properties like torque, angle, and pullout force.
- Material Standards Compliance: Verification against established chemical and mechanical specifications for surgical stainless steel (e.g., composition, strength).
- Biological Standards Compliance: Verification against established ISO standards for biocompatibility, typically involving in-vitro tests (e.g., cytotoxicity) and risk assessments.
- Predicate Device Data: Performance characteristics of the previously cleared predicate device (K080430, STOMA Bone Block Screw) serve as a de facto "ground truth" for demonstrating substantial equivalence.
8. The Sample Size for the Training Set
Not applicable. This is not an AI/ML device, so there is no training set in the sense of machine learning.
9. How the Ground Truth for the Training Set Was Established
Not applicable. There is no training set.
§ 872.4880 Intraosseous fixation screw or wire.
(a)
Identification. An intraosseous fixation screw or wire is a metal device intended to be inserted into fractured jaw bone segments to prevent their movement.(b)
Classification. Class II.