1:17-cv-01041
Dentsply Sirona Inc v. Edge Endo LLC
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Dentsply Sirona Inc. (DE) and Tulsa Dental Products LLC d/b/a Dentsply Sirona Endodontics (DE)
- Defendant: Edge Endo, LLC (NM) and US Endodontics, LLC (NM)
- Plaintiff’s Counsel: Atkinson, Baker & Rodriguez, P.C.
- Case Identification: 1:17-cv-01041, D.N.M., 03/27/2018
- Venue Allegations: Venue is alleged to be proper in the District of New Mexico based on Defendants’ presence, conduct of business, and commission of infringing acts within the state.
- Core Dispute: Plaintiff alleges that Defendant’s EdgeTaper Encore™ endodontic files infringe four patents related to the geometric design and resulting dynamic motion of instruments used in root canal procedures.
- Technical Context: The technology concerns endodontic files, specialized dental instruments used to clean and shape root canals, a market where performance characteristics like flexibility and cutting efficiency are critical.
- Key Procedural History: The complaint notes a prior trademark lawsuit between the parties in the Eastern District of Louisiana, which allegedly resulted in Defendant changing the name of its accused product from “EdgeTaper Next” to “EdgeTaper Encore™.”
Case Timeline
| Date | Event |
|---|---|
| 2005-04-08 | Earliest Priority Date for ’056, ’803, and ’504 Patents |
| 2013-01-01 | Plaintiff launches ProTaper Next® product (approx. date) |
| 2013-01-30 | Earliest Priority Date for ’696 Patent |
| 2014-11-11 | ’504 Patent Issued |
| 2015-01-13 | ’056 Patent Issued |
| 2016-05-31 | ’803 Patent Issued |
| 2017-01-01 | Defendant announces accused product line (approx. Spring) |
| 2017-04-04 | Plaintiff files trademark suit against Defendant |
| 2017-10-31 | ’696 Patent Issued |
| 2018-03-27 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 8,932,056 - “Swaggering Endodontic Instruments” (Jan. 13, 2015)
The Invention Explained
- Problem Addressed: The patent’s background section describes conventional endodontic instruments as being frequently inadequate for cleaning narrow, curved, and calcified root canals, noting they are often predisposed to breakage, which can lead to tooth loss (’056 Patent, col. 1:35-51).
- The Patented Solution: The invention is an endodontic instrument with at least a portion of its body having a center of mass that is offset from its axis of rotation (’056 Patent, Abstract). When rotated, this offset mass causes the flexible instrument to bend and create a wave-like or "swaggering" motion, allowing it to more effectively and safely clean the entire surface of a curved canal (’056 Patent, col. 4:5-24).
- Technical Importance: This "swaggering" dynamic allows for a more flexible instrument that can better navigate curved canals while reducing the torsional stress that leads to instrument breakage.
Key Claims at a Glance
- The complaint asserts independent claim 1 (Compl. ¶50).
- Claim 1 Elements:
- An endodontic device having a tapered body including a tip end, a shank end, and a working surface having multiple cutting edges.
- Wherein at least a portion of a center of mass path of the body revolves around an axis of rotation of the device.
- The complaint does not explicitly reserve the right to assert dependent claims for this patent.
U.S. Patent No. 9,351,803 - “Endodontic Instruments with Offset Centers of Mass” (May 31, 2016)
The Invention Explained
- Problem Addressed: Like the ’056 Patent, this patent addresses the difficulties and risks, such as instrument binding and breakage, associated with preparing a root canal with conventional instruments (’803 Patent, col. 1:19-53).
- The Patented Solution: The invention is an endodontic instrument where the center of mass path spirals around the rotational axis (’803 Patent, Abstract). This specific geometric arrangement produces a swaggering motion that causes one or more cutting edges to be out of contact with the canal wall during use, which is intended to enhance flexibility and debris removal (’803 Patent, col. 4:31-41; Fig. 5).
- Technical Importance: Engineering a specific spiral path for the center of mass provides a distinct method for achieving the desirable swaggering motion while minimizing contact and friction within the canal.
Key Claims at a Glance
- The complaint asserts independent claim 1 (Compl. ¶58).
- Claim 1 Elements:
- An endodontic instrument having a tapered body including a tip end, a shank end, and a working surface having multiple edges.
- Wherein at least a portion of a center of mass path of the body spirals around an axis about which the instrument shank is configured to be driven.
- Wherein when the instrument is driven within a cavity space, one or more edges are out of contact with a wall of the cavity space.
- The complaint does not explicitly reserve the right to assert dependent claims for this patent.
U.S. Patent No. 8,882,504 - “Swaggering Endodontic Instruments” (Nov. 11, 2014)
Technology Synopsis
This patent describes an endodontic instrument where the path of the centers of mass of its transverse cross-sections rotates around the instrument's axis of rotation (Compl. ¶20). This rotation causes the working surface to "swagger," which results in one or more cutting edges being out of contact with the canal wall during operation (Compl. ¶20). The patent further specifies that the cross-sections are polygonal and have a constant number of sides (Compl. ¶20).
Asserted Claims
Independent claim 1 (Compl. ¶66).
Accused Features
The complaint alleges the accused products' working surface swaggers when rotated, that cutting edges are out of contact with the canal wall, and that the cross-sections have a constant and polygonal shape (Compl. ¶¶39-41).
U.S. Patent No. 9,801,696 - “Instruments for Drilling Dental Root Canals” (Oct. 31, 2017)
Technology Synopsis
This patent discloses an instrument with a distinct two-part active area. A first portion, extending from the tip, has its cross-sectional center of mass located on the axis of rotation, while a second portion, following the first, has at least one cross-section with a center of mass that is offset from the axis of rotation (Compl. ¶23). This design combines a centered, stable tip with a flexible, offset body.
Asserted Claims
Independent claim 1 (Compl. ¶74).
Accused Features
The complaint alleges the accused products possess this two-part structure, with a first portion having a centered mass on the axis of rotation and a second portion with an offset mass (Compl. ¶43).
III. The Accused Instrumentality
Product Identification
The accused products are the EdgeTaper Encore™ line of endodontic dental files (Compl. ¶28).
Functionality and Market Context
The EdgeTaper Encore™ files are used by dental professionals to perform root canal procedures (Compl. ¶37). The complaint alleges the products are intended to be "virtually identical" to Plaintiff's ProTaper Next® product line, featuring the same handle design, color-coding scheme for sizes, and are marketed to be used with the "same technique" (Compl. ¶¶30-31). The image provided in the complaint shows a side-by-side comparison of the five-file series from each party, highlighting their visual similarity (Compl. p. 8). Plaintiff further alleges that Defendant markets the accused product as a direct, low-cost replacement, selling for "one third the cost" of Plaintiff's product (Compl. ¶33).
IV. Analysis of Infringement Allegations
’056 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| an endodontic device having a tapered body including a tip end, a shank end, and a working surface having multiple cutting edges | The EdgeTaper Encore™ products are endodontic dental files with a body having a tip end, a shank end, a working surface, and multiple cutting edges. A portion of the body is tapered. | ¶37 | col. 4:55-59 |
| wherein at least a portion of a center of mass path of the body revolves around an axis of rotation of the device | The body of the EdgeTaper Encore™ products has a plurality of transverse cross-sections defining a center of mass path, which rotates around an axis of rotation. | ¶38 | col. 4:1-4, Abstract |
Identified Points of Contention
- Technical Question: The complaint asserts that the accused product's center of mass path "rotates around an axis of rotation" (Compl. ¶38). A central dispute will be the factual and technical evidence required to prove this geometric feature, which is likely to involve expert analysis of the accused products' physical construction.
- Scope Question: The meaning of the term "revolves around" will be a key issue for claim construction. The dispute may focus on whether any geometric asymmetry is sufficient to meet this limitation, or if it requires a specific, continuous orbital path of the center of mass around the central rotational axis.
’803 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| an endodontic instrument having a tapered body including a tip end, a shank end, and a working surface having multiple edges | The accused products are endodontic files with a tapered body having a tip end, shank end, working surface, and multiple cutting edges. | ¶37 | col. 4:51-54 |
| wherein at least a portion of a center of mass path of the body spirals around an axis about which the instrument shank is configured to be driven | The complaint alleges the accused product infringes this claim (Compl. ¶59) and mimics the "asymmetry" of Plaintiff's corresponding product (Compl. ¶34), which embodies the spiraling center of mass path. | ¶¶34, 44, 59 | col. 4:31-35 |
| wherein when the endodontic instrument is driven within an endodontic cavity space, one or more edges of the instrument are out of contact with a wall of the endodontic cavity space | When the accused products are rotated, one or more of their cutting edges are out of contact with the wall of the endodontic cavity space. | ¶40 | col. 4:38-41 |
Identified Points of Contention
- Technical Question: The infringement allegation hinges on whether the accused product's center of mass path "spirals" around its axis. This is a more specific limitation than the "revolves" term in the ’056 patent and may require more detailed evidence of the product's precise geometry. The complaint's comparison of marketing materials, where both parties describe a "rectangular cross-sectional shape," may be used to suggest a structural similarity that gives rise to the claimed spiraling path (Compl. p. 9).
- Scope Question: Does the term "spirals" require a continuous helical path for the center of mass, or could it be construed more broadly to cover other forms of progressive, rotational offset?
V. Key Claim Terms for Construction
The Term: "revolves around an axis of rotation" (’056 Patent, Claim 1)
Context and Importance
This term defines the core "swaggering" concept of the ’056 patent. Its construction will determine whether a general geometric asymmetry is sufficient for infringement or if a more specific orbital motion of the center of mass is required. Practitioners may focus on this term because the complaint's infringement theory rests on the allegation that the accused product's design creates this specific dynamic motion.
Intrinsic Evidence for Interpretation
- Evidence for a Broader Interpretation: The claim language itself is general, not specifying the shape or nature of the revolution. The specification notes that the effect is produced by having a section with a center of mass "offset from an axis of rotation" (’056 Patent, Abstract), which could be argued to encompass various forms of asymmetry.
- Evidence for a Narrower Interpretation: The patent title "Swaggering Endodontic Instruments" and descriptions of the instrument bending "away from the axis of rotation" suggest a dynamic, wave-like motion, which could support a narrower construction requiring more than a static offset.
The Term: "spirals around an axis" (’803 Patent, Claim 1)
Context and Importance
This term distinguishes the ’803 patent from the more general "revolves" concept. The infringement case for this patent depends entirely on whether the accused product's geometry creates this specific type of path for its center of mass.
Intrinsic Evidence for Interpretation
- Evidence for a Broader Interpretation: A party might argue "spirals" does not require a perfect mathematical helix but can describe any path that is both rotational and progressive along the axis.
- Evidence for a Narrower Interpretation: The patent’s detailed description and figures, such as Figure 5, which illustrates grooves that "spiral around the shaft," provide a specific technical context for the term (’803 Patent, col. 8:51-53). This could be used to argue that the term requires a continuous, helical-like path.
VI. Other Allegations
Indirect Infringement
The complaint does not plead a separate count for indirect infringement.
Willful Infringement
The complaint alleges that Defendants had actual, pre-suit knowledge of the ’056, ’803, and ’504 patents (Compl. ¶45). Willfulness is further supported by allegations that Defendants engaged in a "pattern and practice of copying Dentsply Sirona products" (Compl. ¶35), intentionally designed their product to be "virtually identical" to Plaintiff's product (Compl. ¶30), and mimicked Plaintiff's promotional descriptions (Compl. ¶34).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of technical identity: can Plaintiff prove, likely through reverse engineering and expert testimony, that the physical geometry of the accused EdgeTaper Encore™ files creates the specific center-of-mass dynamics required by the claims, such as a path that "revolves" or "spirals" around the rotational axis?
- The case may also turn on a question of definitional scope: how will the court construe the key motion-related terms "revolves around" and "spirals around"? The resolution will depend on whether these terms are interpreted broadly to cover general asymmetry or narrowly to require the specific, engineered paths illustrated in the patent specifications.
- A key evidentiary question will be one of intent: do the allegations of mimicking product design, color-coding, and marketing materials rise to the level of supporting a finding of willful infringement, particularly given the allegation of pre-suit knowledge of three of the four patents?