Obviousness

US Patent 115899970, "Intraoral device with detachable mouth prop," can be found obvious under 35 U.S.C. § 103 by combining various prior art references, particularly by a person having ordinary skill in the art (PHOSITA) seeking to improve hands-free dental suction, isolation, and patient comfort. The background of US11589970 itself notes a "need in the art for improved systems and methods of providing dental services in a more efficient, comfortable, and safe manner to the dental patient."

Obviousness Analysis for Independent Claims 1 and 18

The independent claims of US11589970 describe a dental mouthpiece with a main body forming a pocket for fluid collection, a suction connector, and a detachable mouth prop. A key feature is a "bridge structure" within the pocket designed to prevent wall collapse during suction, and the suction connector extending through or past the mouth prop.

A PHOSITA, motivated to address the known need for more efficient and hands-free dental procedures, would consider combining existing dental devices that perform related functions.

Combination 1: US20080318183A1 (Suzman) + US5037298A (Hickham) + General Engineering Principles.

1. Primary Reference: US20080318183A1 to Suzman ("Bite block with snap-in positionable fluid ejector," published 2008-12-25)

   • Disclosure: Suzman discloses a dental device that combines a "bite block" (which serves as a mouth prop) with a "snap-in positionable fluid ejector" (which serves as a suction connector). This reference teaches the core concept of integrating a mouth prop and a suction mechanism.
   • Contribution to Claims: This reference directly addresses the features of a "mouthpiece comprising... a suction connector... and a mouth prop." The "positionable" nature of the fluid ejector suggests it can be arranged relative to the bite block for optimal function, including extending "through and past" it for effective fluid removal during a procedure. The "molded in one piece" aspect of the mouth prop is a common manufacturing choice for dental devices made from flexible materials like silicone, as described in US11589970.

2. Secondary Reference: US5037298A to Hickham ("Apparatus and improved process for removing saliva while retracting cheeks and lips," published 1991-08-06)

   • Disclosure: Hickham describes an apparatus for removing saliva while simultaneously retracting a patient's cheeks and lips. Such a device inherently defines an intraoral working space or "pocket" for efficient saliva collection and oral cavity isolation. The device would necessarily include "walls" that form this pocket to retract tissue and guide fluids.
   • Contribution to Claims: Hickham teaches the "main body portion configured as a pocket at least partially enclosing an interior space... defined by: a first wall... a second wall... and a connecting wall." The specific shaping of these walls (e.g., narrower at one end) would be a routine design choice for adapting to different mouth anatomies, a common consideration in dental device design.
   • Motivation to Combine Suzman and Hickham: A PHOSITA would be motivated to combine the integrated bite block/suction of Suzman with the effective oral cavity isolation and fluid collection "pocket" from Hickham. This combination would yield a more comprehensive and efficient, hands-free device for dental procedures, fulfilling the recognized need for improved systems that offer both biting support and effective isolation/fluid management, thus reducing the number of separate tools a dental assistant must manage.

3. Third Component: General Engineering Principles for Maintaining Patency in Flexible Suction Conduits.

   • Problem: Flexible suction devices, like the fluid ejector in Suzman or the saliva removal apparatus in Hickham, can experience collapse of their walls under vacuum, restricting or halting fluid flow. This is a known engineering problem in systems involving flexible conduits under suction.
   • Known Solutions: A PHOSITA would be aware of standard engineering solutions to prevent the collapse of flexible tubes or chambers under vacuum. These solutions commonly involve incorporating internal support structures such as ribs, baffles, or protrusions to maintain the separation of opposing walls and ensure continuous flow.
   • Contribution to Claims: Applying this general engineering principle to the flexible walls of the "pocket" in the combined Suzman-Hickham device would lead directly to the "bridge structure that includes a plurality of protrusions integral with and protruding from an interior surface of the second wall and extending across the distance between the first wall and the second wall, wherein the bridge structure is not attached to the first wall, and wherein the plurality of protrusions... protrude... in a wave shape comprising one or more crests and one or more troughs." The specific wave shape with crests (contact points) and troughs (gaps for flow) would be an obvious design choice for an engineer to effectively maintain separation and facilitate fluid movement, while being integral to the molded flexible material.
   • Motivation to Incorporate: When combining the flexible components of Suzman and Hickham for improved hands-free suction, a PHOSITA would be motivated to incorporate known anti-collapse mechanisms to ensure the reliability and efficiency of the suction system, thereby achieving predictable results (uninterrupted fluid evacuation).

Conclusion on Obviousness:

Claims 1 and 18 of US11589970 would have been obvious to a PHOSITA before the priority date of December 7, 2012. The combination of Suzman's integrated mouth prop and suction, Hickham's oral isolation and fluid collection pocket, and the well-known engineering principles for preventing collapse in flexible suction conduits, collectively teach all the elements of the independent claims. A PHOSITA would have been motivated to combine these known elements to create a more efficient, comprehensive, and reliable hands-free dental suction and isolation device, solving existing problems in dental practice with predictable results.