(809 days)
Bone-Lock implants may be used for every indication generally prescribed for dental implants; in fact, the design and materials of the Bone-Lock implants were chosen, after extensive study, for successful use in even the most difficult patients, such as tumor patients with grafted and/or irradiated bone.
Principally, every patient receiving implants should be integrated in a treatment concept that entails restoring the entire dentition. Implantation should only be carried out in motivated, cooperative patients with good oral hygiene. There is no limit in terms of age; in fact, better results can be achieved with older than with younger patients (Tetsch 1991, as referenced in Exhibit A. "Indication, Planning, and Clinical Procedure," p. 4). Young patients should not be given dental implants until the jaw has ceased to grow. Other alternatives should be considered for young patients, such as orthodontic gap closure, replantation, or modern prosthetic treatment (e.g. adhesive bridges). The minimum age for implantation should be set at 16 years. Prosthesis intolerance, regardless of age, is an important inclusion criterion. If despite proper functioning, conventional dentures jeopardize one's profession (e.g. speakers, singers, actors, and musicians), this aspect should also be taken into account in indicating implant treatment.
A prerequisite for local indications is the vital and intact periodontium with good oral hygiene. The particular indications for the Bone-Lock system are those recognized by all the consensus conferences:
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- single-tooth replacement
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- insertion of additional posts
- free-end situations
- edentulous patients
Conditions that reinforce these indications include severe nausea or allergy to the plastic used for external prostheses.
Conditions for implant placement are considered ideal when the implants are covered on the lingual and buccal sides with a more than 1 mm thick layer of bone. Bone height under 1 cm in the interforaminal region is a contraindication for implantation as the sole treatment.
The Bone-Lock dental implant is a tapered screw with a cone angle of 2° 30' that simulates the shape of the root of the tooth. Under axial load applied to the Bone-Lock dental implant, a greater load is seen on the anchoring bone in the area of the screw tip. However, because the screw is rounded, it transfers the mechanical forces over the entire surface area of the tip, and not just at certain points (see Exhibit A, "Basic Concept and Scientific Information," p. 7 and Exhibit E, Engineering Drawings). The optimized cone angle reinforces this effect (Bossler 1981, as referenced in Exhibit A, "Basic Concept and Scientific Information," p. 7).
Photoelastic analysis illustrates the load-bearing conditions of the Bone-Lock system compared to other dental implants under axial load. Starting from the tip, the load on the anchoring bone towards the screw neck region decreases by one ordinal number per thread pitch (ibid., p. 7, fig. 4). The isochromatic lines illustrate a thread pattern with decreasing ordinal numbers starting at the thread crest towards the core of the screw. In contrast to the Heinrich screw, for example, the strain decreases 0.5 to 3 ordinal numbers at the most, depending on the stress, but without showing load-free anchor zones. This yields the following state in the area of the thread: the anchoring material at the crest of the thread is subjected to strong mechanical load. Though inside the thread this mechanical load is only slightly weaker (decreasing), shear forces are far weaker than with implants with load-free zones on the threads or steps (ibid., p. 7, fig. 5). Due to the special design of the screw thread, the axial pressure is transferred not only over the tip of the implant and the outer edges of the thread, but also over its entire surface. This can be seen by the course of the isochromatic lines in the threads. They course at an angle that opens upwards towards the core of the screw. Placing a secant on the thread profile parallel to the isochromatic lines results in a point of minimal load within one thread pitch. If a line is placed through this point perpendicularly to the isochromatic lines, the approximate direction of stress can be depicted, which runs from the body of the screw diagonally downwards and outwards. The base of the thread is thus subjected to load such that it can be supported by the outside anchoring tissues and its load-bearing properties are not overtaxed. Shear strains occur parallel to the secant, the existence of which are indicated by the decreasing isochromatic ordinal number The special form of the thread, however, prevents shearing forces from in the threads. dominating, since there are no load-free spaces with low ordinal numbers (ibid).
If the force is induced at an angle of 45°, the neck region is subjected to the most mechanical load. A zone of uniform load on the two sides of the screw is noticeable, however, the ordinal number on the compression side of the screw is higher (7) than on the tensile side (2), which is subjected to only minimal mechanical load. The tip of the screw is subjected to less load than at the axial pressure point. The center of load is located at the point where the first thread pitch starts. Most of the horizontal tensile load is transferred from the implant to the neck region. The remainder of the screw profile is subjected to almost uniform load over its entire contour. No similar balance of compression and tensile stress was achieved with any other implant in the study.
In summary, it can be said that the Bone-Lock implant in its final form exhibits the most balanced photoelastic behavior of all screw-shaped implants tested. A full description of the mechanical design of the Bone-Lock dental implant can be found in the product brochure entitled "Basic Concept and Scientific Information", Exhibit A.
Leibinger's Bone-Lock endosseous implant system is pure titanium. The endosteal section, i.e. the root and subgingival portion of the transgingival section, is coated with semi-conductive titanium-zirconium-oxide (Ti, Zr) O, and the supragingival part of the connecting component (transgingival section) is coated with titanium-niobium-oxinitride (Ti, Nb) ON. The (Ti, Zr) O layer - aside from surface deviations - is composed approximately of 35 atomic percent (at%) titanium, 15 at% zirconium, and 50 at% oxygen. Similarly, the (Ti, Nb) ON layer is approximately 33 at% titanium, 23 at% niobium, 41 at% nitrogen, and 3 at% oxygen. The advantage of the addition of Niobium and Zirconium is the high formation enthalpies of the oxides, which are higher for Niobium and Zirconium than for titanium and contribute to the chemical long-term stability of the coating material. A full description and the benefits of these coating materials is given in the product brochure entitled "Scientific Documentation", Exhibit A. A listing of all components and materials can be found in Exhibit D.
The Bone-Lock Implant is manufactured and packaged at Leibinger GmbH, Bötzinger Straße 41 D-79111 Freiburg Germany. The facility is ISO 9001 certified; all processing and storage practices are executed in accordance with a comprehensive quality system (see Exhibit G).
The acceptance criteria and study proving device performance are described below based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Success Rate (General) | 92.2% following an implantation time of >365 days |
| Success Rate (Normal Patients) | 90.6% |
| Success Rate (Tumor Patients) | 95.1% |
| Periimplant Bone Resorption (Average, 1st year) | 1.2 mm |
| Periimplant Bone Resorption (Average, 2nd year) | 0.7 mm |
| Periimplant Bone Resorption (Average, 3rd year) | 0.4 mm |
| Mechanical Load Distribution (Photoelastic Behavior) | Bone-Lock implants exhibited the most balanced photoelastic behavior of all screw-shaped implants tested. |
| Plaque Deposit Inhibition | "Positive oral hygiene situation among our case material is a confirmation of the plaque deposit-inhibiting effect of Titanium Niobium Oxynitride..." |
| Inflammation | Good, inflammation-free mucous membrane situation with mean Gingiva Index of 0.52 and Sulcus Bleeding Index of 0.81. |
2. Sample Size for Test Set and Data Provenance
- Sample Size:
- Clinical Study: 174 patients with a total of 585 implants were initially fitted. After accounting for loss to follow-up and deaths, the regular recall scheme encompassed 153 patients with a total of 505 implants.
- Success Rate Evaluation: Data from 346 implants that underwent regular follow-up examinations in the recall scheme were evaluated for success rate.
- Data Provenance: The study was conducted at the Department of Oral-Maxillofacial Surgery at the University of Würzburg (Germany). This indicates the data is retrospective as it was collected from July 1988 and December 1993, and reported in 1997.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
The document does not explicitly state the number of experts used or their specific qualifications for establishing the ground truth of the clinical data. The study was conducted at a university department, implying assessment by qualified medical professionals (e.g., oral and maxillofacial surgeons), but specific details are not provided.
4. Adjudication Method for the Test Set
The document does not mention an explicit adjudication method (e.g., 2+1, 3+1). The "regular three-month recall" implies follow-up examinations were conducted by the clinical team at the University of Würzburg, but specific adjudication processes for uncertain cases are not described.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done, and Effect Size
No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done. The clinical study focuses on the performance of the Bone-Lock implants themselves and doesn't compare human readers' performance with and without AI assistance.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was Done
This question is not applicable as the device is a dental implant, not an AI algorithm. The studies conducted are clinical investigations, non-clinical laboratory studies (photoelastic analysis), and animal experimental investigations.
7. The Type of Ground Truth Used
The ground truth for the clinical study was based on clinical observation and measurements during regular follow-up examinations (e.g., Hygiene Index, Gingiva Index, Sulcus Bleeding Index, Pocket Probing Depth, and bone resorption measurements) and ultimately the success or failure (explants) of the implants. This is essentially patient outcome data and expert clinical assessment.
8. The Sample Size for the Training Set
This question is not applicable as the device is a physical dental implant, not an AI algorithm that requires a training set. The clinical study described is a performance evaluation of the device itself.
9. How the Ground Truth for the Training Set Was Established
This question is not applicable for the same reason as point 8.
§ 872.3640 Endosseous dental implant.
(a)
Identification. An endosseous dental implant is a prescription device made of a material such as titanium or titanium alloy that is intended to be surgically placed in the bone of the upper or lower jaw arches to provide support for prosthetic devices, such as artificial teeth, in order to restore a patient's chewing function.(b)
Classification. (1) Class II (special controls). The device is classified as class II if it is a root-form endosseous dental implant. The root-form endosseous dental implant is characterized by four geometrically distinct types: Basket, screw, solid cylinder, and hollow cylinder. The guidance document entitled “Class II Special Controls Guidance Document: Root-Form Endosseous Dental Implants and Endosseous Dental Implant Abutments” will serve as the special control. (See § 872.1(e) for the availability of this guidance document.)(2)
Classification. Class II (special controls). The device is classified as class II if it is a blade-form endosseous dental implant. The special controls for this device are:(i) The design characteristics of the device must ensure that the geometry and material composition are consistent with the intended use;
(ii) Mechanical performance (fatigue) testing under simulated physiological conditions to demonstrate maximum load (endurance limit) when the device is subjected to compressive and shear loads;
(iii) Corrosion testing under simulated physiological conditions to demonstrate corrosion potential of each metal or alloy, couple potential for an assembled dissimilar metal implant system, and corrosion rate for an assembled dissimilar metal implant system;
(iv) The device must be demonstrated to be biocompatible;
(v) Sterility testing must demonstrate the sterility of the device;
(vi) Performance testing to evaluate the compatibility of the device in a magnetic resonance (MR) environment;
(vii) Labeling must include a clear description of the technological features, how the device should be used in patients, detailed surgical protocol and restoration procedures, relevant precautions and warnings based on the clinical use of the device, and qualifications and training requirements for device users including technicians and clinicians;
(viii) Patient labeling must contain a description of how the device works, how the device is placed, how the patient needs to care for the implant, possible adverse events and how to report any complications; and
(ix) Documented clinical experience must demonstrate safe and effective use and capture any adverse events observed during clinical use.