Surgery – Specula – Retractor
Reexamination Certificate
2000-08-01
2001-05-22
Hirsch, Paul J. (Department: 3732)
Surgery
Specula
Retractor
C600S239000
Reexamination Certificate
active
06234962
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to the field of equine dentistry and more particularly to equine oral speculums.
BACKGROUND OF THE INVENTION
Equine speculums have been used for over one hundred years. Early prior art speculums engaged the molars, whereas newer forms engage the incisors. One form of equine speculum used is that described in U.S. Pat. No. 5,704,901 to Meister, generally comprise U-shaped upper and lower jaw pieces extending from one side of the horses head, around past the teeth and lips to the other side of the horses head. Plates at the front of the upper and lower jaw pieces engage the incisors. The speculum is held in the mouth by means of adjustable nose and head straps, much like a bridle. A handle or lever mechanism is attached pivotally to the speculum so as to allow the user to force the lower jaw piece to rotate respective to the upper, thereby opening the horse's mouth. A single tooth pawl located on the handle, engages one of a series of teeth on the front of the lower jaw piece to maintain the open mouthed position allowing the user full access to the mouth and cheek teeth.
Other widely used variations have ratchet assemblies at the rear of the speculum, generally one on each side, used to mechanically force the jaws apart.
In the hands of capable professionals, existing dental speculums can be used with success to perform dental procedures.
Problems occur when horse owners and trainers wish to inspect the condition of their horse's teeth, either before or after dental procedures have been performed. As the cheek teeth are obscured unless the mouth is open, a speculum must be used to view them. Existing speculums are heavy and difficult to operate. In the case of the ratcheted speculum, the device must be opened first on one side and then on the other. The speculum can be opened too far, risking damage to the apparatus, but more importantly inflicting damage to the horse's jaws. Levered or ratcheted speculums present a very real danger for trapping or catching of fingers and skin within the pawls or ratchet devices. Once in place, there is a tendency for the user to put their hands inside the horse's mouth. If installed improperly, the incisors can come sideways off the plates, at the front of the speculum, and the user can be badly bitten.
An objective of the present invention is to provide a one-piece, single position speculum that can be readily inserted by those unskilled in equine dental practices, allowing the user to easily view all of the cheek teeth. Further, it is an objective to provide a speculum that does not allow the user to place their hands inside the horse's mouth while inspecting the teeth.
SUMMARY OF THE INVENTION
An equine dental speculum for viewing a horse's teeth is provided comprising a one-piece open frame, upper and lower bite plates affixed to the front of the frame and two V-shaped projections spanning from upper to lower bite plate, one at each side of the bite plates and extending into the mouth. Once inserted, the speculum is held in place by nose and head straps, attached to the speculum.
More particularly, the front of the speculum comprises upper and lower horizontally-extending and parallel bite plates which are spaced apart for engaging top and bottom incisors and holding the jaws open at an optimal position for viewing. The bite plates are spaced apart using one or more vertical supports. A wedge, having a base and rearwardly converging upper and lower surfaces forming an apex, is joined, at the base, to the upper and lower bite plates. The wedge surfaces act to guide the incisors to their respective bite plates. A pair of attachment members extend rearwardly from the front of the speculum to enable attachment of straps for securing the speculum in the horse's mouth.
The wedge is formed of two V-shaped projections which are spaced laterally apart, but are close enough to engage the incisors. The open ends of each V-shaped projection form the base and join with the upper and lower bite plates.
Each of the two attachment members comprises a U-shaped frame which is open for viewing the cheek teeth. The two U-shaped frames are spaced laterally apart so as to fit externally on either side of the horse's mouth. The open ends of each frame member attach to the front of the speculum, preferably to the upper and lower bite plate.
Strap attachment points are positioned at the rearmost end and along the length of the attachment members for securing the speculum in the horse's mouth.
As the speculum is inserted into the horse's mouth the incisors engage the surfaces of the two V-shaped projections which act as wedges to force the incisors and the jaws apart. When fully inserted, the incisors rest against the upper and lower bite plates to hold the jaws open. Nose and head straps attached to the open frame hold the speculum in place, allowing the user to view the incisors and the cheek teeth. Preferably, the V-shaped projections, positioned at the front of the speculum, are spaced close enough so as to prevent the user from putting their hands into the horse's mouth without obscuring the view of the inner surfaces of the cheek teeth.
REFERENCES:
patent: 843040 (1907-02-01), Seabrant
patent: 1331542 (1920-02-01), Vose
patent: 1383421 (1921-08-01), Forgrave
patent: 1915454 (1933-06-01), Steigenberger
patent: 4450831 (1984-05-01), Jeffrey
patent: 5199418 (1993-04-01), Jamison et al.
patent: 5704901 (1998-01-01), Meister
patent: 5718665 (1998-02-01), Stubbs
patent: 5799617 (1998-09-01), Long et al.
patent: 5842974 (1998-12-01), Stubbs
patent: 5888064 (1999-03-01), Stubbs
patent: 613131 (1935-05-01), None
Goodwin Sean W.
Hirsch Paul J.
LandOfFree
Equine dental speculum does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Equine dental speculum, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Equine dental speculum will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2448461