Dentsply Sirona Inc v. Osseo Imaging LLC

1. Case Identification

• Case #: IPR2025-00772
• Patent #: 6,944,262
• Filed: March 26, 2025
• Petitioner(s): Dentsply Sirona Inc.
• Patent Owner(s): Osseo Imaging, LLC.
• Challenged Claims: 1, 2, 4, 6

2. Patent Overview

• Title: Dental and Orthopedic Densitometry Modeling System and Method
• Brief Description: The ’262 patent discloses a digital modeling system for creating three-dimensional (3D) dental or orthopedic models of patients. The system uses an energy source and sensor to generate tomographic data, from which a computer creates, stores, and compares densitometry models without the use of fiducial markers.

3. Grounds for Unpatentability

Ground 1: Claims 1, 2, 4, and 6 are anticipated by or obvious over Massie

• Prior Art Relied Upon: Massie (WO 01/39667), Xu (Patent 6,363,163), and Milestone (WO 98/36683).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Massie, an international publication of the U.S. application that is the parent of the ’262 patent, anticipated every limitation of claim 1. Massie allegedly disclosed a CT system with a computer, memory, input/output, and an X-ray source and detector for creating tomographical densitometry models. Petitioner contended that Massie’s disclosure of creating 3D models and its silence on fiducial markers met the corresponding claim limitations. The dependent claims were argued to be met by Massie’s disclosure of an external, collimated X-ray source and sensor.
  • Motivation to Combine (for §103 grounds): Alternatively, Petitioner argued it would be obvious to combine Massie with Xu or Milestone. A Person of Ordinary Skill in the Art (POSA) would combine the system in Massie with the well-known software methods for comparing medical images taught by Xu (temporal subtraction) and Milestone (comparison to baseline models) to enhance diagnostic capabilities and track patient treatment over time.
  • Expectation of Success (for §103 grounds): A POSA would have a reasonable expectation of success in programming Massie’s computer to perform comparisons, as such software was commercially available and its implementation was a routine practice in medical imaging.

Ground 2: Claims 1, 2, 4, and 6 are obvious over Arai in view of Xu, Milestone, and/or Cann

• Prior Art Relied Upon: Arai (Patent 6,118,842), Xu (Patent 6,363,163), Milestone (WO 98/36683), and Cann (a 1980 journal article).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner asserted that Arai disclosed a dental X-ray imaging apparatus capable of CT imaging that met most limitations of claim 1. Arai taught a system with a computer, memory, an external X-ray source and sensor, and software to generate tomographic models of dental structures. Arai’s use of cone beam CT inherently created 3D datasets, and the system did not require fiducial markers.
  • Motivation to Combine (for §103 grounds): A POSA would combine Arai with Xu or Milestone for the same reasons as in Ground 1: to add the clinically desirable function of comparing images for diagnosis and monitoring. As an alternative, Petitioner argued that if Arai’s system were not considered inherently quantitative, a POSA would combine it with Cann. Cann taught using quantitative CT with calibration phantoms to precisely measure bone density. A POSA would combine these teachings to improve the accuracy of densitometry measurements for applications like pre-implant assessment, making Arai’s system more versatile.
  • Expectation of Success (for §103 grounds): A POSA would expect success in adding comparison software to Arai’s system or incorporating Cann’s quantitative techniques, as both involved applying known methods to conventional CT systems to achieve predictable improvements.

Ground 3: Claims 1, 2, 4, and 6 are obvious over Pelc in view of Xu, Milestone, and/or Cann

• Prior Art Relied Upon: Pelc (WO 94/10908), Xu (Patent 6,363,163), Milestone (WO 98/36683), and Cann (a 1980 journal article).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Pelc disclosed a "tomographic bone scanning system" for evaluating bone density and morphology. This system included a computer, mass storage, an external radiation source and detector on a C-arm, and software to reconstruct tomographic models, meeting most limitations of claim 1. Pelc taught generating 3D models by acquiring images from multiple gantry angles and did not require fiducial markers.
  • Motivation to Combine (for §103 grounds): The motivation to combine Pelc with Xu or Milestone was to implement the known and beneficial function of comparing tomographic models. The motivation to combine Pelc with Cann was to improve the accuracy of the bone density evaluations, a stated purpose of the Pelc system, by using Cann’s established quantitative calibration methods.
  • Expectation of Success (for §103 grounds): A POSA would have a high expectation of success, as combining these references involved implementing standard comparison software or applying well-understood quantitative CT techniques to Pelc’s conventional CT architecture.

4. Key Claim Construction Positions

• "Densitometry": Petitioner adopted the district court construction of "Quantitatively calculated bone density."
• "Three-dimensional digital densitometry model": Petitioner adopted the construction "A digital three-dimensional model, i.e., a digital model constructed from two or more focal planes."
• "Fiducial marker": Petitioner proposed the construction "An x-ray attenuating object on or within the structure to be imaged that serves as a reference point," arguing this is the term's plain meaning as understood by a POSA. This construction is central to the argument that the prior art’s silence on markers satisfies the negative limitation.

5. Key Technical Contentions (Beyond Claim Construction)

• Priority Date: Petitioner contended that the challenged claims were not entitled to the priority date of the earliest parent application (December 1, 1999) but only to the filing date of the continuation-in-part (CIP) application (January 24, 2003). The argument was that the CIP introduced new matter—the use of electron beams as an energy source—which was encompassed by the broad claim term "an energy source." Because the parent applications only disclosed X-rays, they did not provide written description support for the full scope of the claims, making intervening publications like Massie available as prior art.

6. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under 35 U.S.C. §314(a) based on Fintiv factors was inappropriate. It was asserted that the co-pending district court litigation was at a nascent stage, as an answer had not yet been filed and no trial date or other substantive deadlines had been set.

7. Relief Requested

• Petitioner requested institution of an inter partes review (IPR) and cancellation of claims 1, 2, 4, and 6 of the ’262 patent as unpatentable.