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Obsidian® NOW is used to fabricate ceramic dental prosthesis in the nature of crowns for posterior and anterior applications using CAD/CAM technology. The block is processed through dental laboratories or by dental professionals.

Obsidian® NOW is a fully crystallized lithium disilicate glass-ceramic block that can be milled to produce dental restorations using CAD/CAM technology. The block is intended to be used for fabricating monolithic restorations such as full contour crowns without requiring any additional crystallization prior to placement. The milling block is offered in the commonly used VITA® Classical and Chromascop® Bleach shades.

Here's a breakdown of the acceptance criteria and the study that demonstrates the device meets these criteria, based on the provided text.

1. Table of Acceptance Criteria and Reported Device Performance:

2. Sample Size Used for the Test Set and Data Provenance:

The document does not explicitly state the exact sample sizes for each specific test within the "test set" (non-clinical tests). However, for many tests, it mentions that "all shades offered for Obsidian® NOW" were tested or "the worst cases were tested."

• Flexural Strength: Tested on "all shades offered for Obsidian® NOW."
• Visual Shade Evaluation: "All shades offered for Obsidian® NOW were evaluated."
• Color Consistency: Tested on "all shades offered for Obsidian® NOW."
• Uniformity of Color: Tested on "all shades offered for Obsidian® NOW."
• Chemical Solubility: "The worst cases were tested."
• Radioactivity: "Tested on the worst cases."
• Freedom from Extraneous Materials: "All shades offered for Obsidian® NOW were tested."
• Glass Transition Temperature: "All shades offered for Obsidian® NOW were tested."
• Biocompatibility: Based on "cytotoxicity testing results from the subject device." Implies testing on representative samples.
• Packaging Validation: Tested on "Obsidian® NOW" packaging.

The data provenance is retrospective as these are non-clinical lab tests performed on the manufactured device, not on actual patients. The document does not specify the country of origin for the data; it would typically be the location of the testing laboratories.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts:

• Visual Shade Evaluation: "qualified evaluators" were used. Their specific number or qualifications (e.g., years of experience, dental professional titles) are not specified in this document.
• For other tests like "Freedom from Extraneous Materials" and "Uniformity of Color," visual inspection by unspecified personnel established the ground truth.

4. Adjudication Method for the Test Set:

Given that many of the tests are objective laboratory measurements (e.g., flexural strength, chemical solubility, radioactivity, glass transition temperature, color consistency ΔE calculation), an adjudication method (like 2+1 or 3+1) is not applicable as there is no subjective interpretation to resolve.

For the qualitative visual inspections (Visual Shade Evaluation, Freedom from Extraneous Materials, Uniformity of Color), the document mentions evaluations by "qualified evaluators" or "visual inspection," but it does not specify any formal adjudication method if multiple evaluators were involved or disagreed. It simply states the evaluations "concluded" or "assessed."

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:

No, a multi-reader multi-case (MRMC) comparative effectiveness study was not conducted or reported. This submission specifically states: "No clinical data is included in this submission." The studies presented are non-clinical (laboratory and in-vitro performance tests).

6. Standalone (Algorithm Only) Performance Study:

No, a standalone (algorithm only) performance study was not conducted or reported. This device is a physical material (a glass-ceramic milling block) used in dentistry, not an AI algorithm or software. Therefore, the concept of "algorithm only performance" is not relevant to this submission. The device itself is the "standalone" component being evaluated.

7. Type of Ground Truth Used:

The ground truth for the non-clinical tests was established by:

• Objective laboratory measurements: This applies to Flexural Strength, Chemical Solubility, Radioactivity, Glass Transition Temperature, and Color Consistency (ΔE calculation). The "truth" is the measured physical or chemical property of the material.
• Expert Consensus/Visual Inspection: For Visual Shade Evaluation, Freedom from Extraneous Materials, and Uniformity of Color, the ground truth was established by visual assessment by "qualified evaluators" or general visual inspection against established standards (e.g., VITA® Classical shade guide).
• Biocompatibility Standard (ISO 10993-1): The ground truth for biocompatibility was adherence to the testing requirements and criteria outlined in this international standard.
• Packaging Standard (ASTM D4169-22): The ground truth for packaging validation was successful completion of tests outlined in this standard, confirmed by visual inspection for damage.

8. Sample Size for the Training Set:

The concept of a "training set" is not applicable to this device. This is a physical dental material, not an AI/ML algorithm or software that requires training data. The document describes non-clinical performance testing of the final manufactured product.

9. How the Ground Truth for the Training Set Was Established:

As mentioned above, a "training set" is not applicable here since the device is a physical material and not an AI/ML system.

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