US 4167814

Patent Overview — US 4,167,814

Title: Mouth prop and oral evacuation device
Patent number: US 4,167,814 A
Application number: US05/786,147
Inventor: Robert E. Schubert
Assignee: Individual (original assignee: Individual)
Filing date / Priority date: 1977-04-11
Publication (grant) date: 1979-09-18
Legal status (as listed): Expired – Lifetime; anticipated expiration 1997-04-11
Source: https://patents.google.com/patent/US4167814/en

Purpose: Dental work such as drilling and grinding uses a sprayed cooling/washing fluid that must be constantly removed, while the mouth is held open and the tongue kept away from the work area. The patent addresses the drawbacks of prior evacuation devices and tongue shields — particularly the lack of adequate means for holding an evacuation device in place, and complicated, difficult-to-use designs. The stated objects are to provide a combined oral evacuation and mouth prop device, and one that also includes a tongue shield.

Plain-language scope (per the supplied description and abstract): A generally U-shaped suction tube fits inside the lower jaw, below the tongue and inside the row of teeth. One leg has a closed end; the other has an upwardly turned portion with a forwardly extending connecting tube for attachment to a suction hose. Fluid-collecting perforations are placed in the lower portion of the tube so the openings remain under the fluid and do not lose suction by becoming uncovered. A wedge-shaped mouth prop, preferably of resilient plastic or rubber, fits between the upper and lower teeth and holds the tube in place. A tongue guard extends upward from the tube and curves inward above the tongue. The prop and tube are preferably joined by easily releasable means such as resilient detent ribs, allowing independent construction, different sizes, selective assembly, and possible disposability. FIG. 5 shows an alternate arrangement with a tube closed at both ends and a connecting conduit spaced from the closed end, permitting the tube leg to extend further back in the mouth.

Not established by the excerpt: the full claims and their exact wording, the complete description (text is expressly excerpted), the detailed content of FIGS. 1–5 and the section taken on line 3—3, and the specifics of the alternate connecting means mentioned as possible.