Tooth crown remover

An elongated mandrel is coaxially secured at one end to one end of a larger diameter handle. The other end portion of the mandrel converges and terminates in an annular outstanding shoulder facing the handle. A sleeve-like hammer slidably surrounds the mandrel and is spring urged for impacting on the adjacent handle end when manually moved away from the handle and released. The hammer is provided with an outstanding flange adjacent the handle for manually moving the hammer away from the handle.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to dental tools and more particularly to a 
tooth crown remover. 
It is sometimes necessary to remove a crown from a tooth in order to remove 
decayed portions of the tooth and replace the crown. Since the crown in 
place fits and completes the contour of the tooth, the old crown is 
usually difficult to remove. 
This invention provides a hand held tool which will engage the edge of the 
crown overlapping the tooth and effectively remove it from the tooth. 
2. Description of the Prior Art 
I do not know of any patents disclosing a tooth crown remover. 
SUMMARY OF THE INVENTION 
An elongated mandrel is diametrically reduced at one end portion and 
coaxially secured to one end of a larger diameter handle. The end portion 
of the mandrel, opposite the handle, converges toward its free end and 
terminates in a small diameter head defining a thin edge annular lip or 
shoulder facing the handle and perpendicular to the longitudinal axis of 
the mandrel. A centrally bored and counterbored hammer slidably surrounds 
the end portion of the mandrel connected with the handle and defines an 
annular space around the diametrically reduced end portion of the mandrel 
which receives a helical spring normally urging the hammer toward the 
handle. The hammer is characterized by a diametrically enlarged annular 
outstanding flange adjacent its end facing the handle. The end surface of 
the handle connected with the mandrel forms an anvil against which the 
adjacent end of the hammer impacts when the user, by grasping the handle, 
moves the hammer toward the free end of the mandrel with his thumb and 
releases it. 
The principal object of this invention is to provide a hand tool for 
removing a crown from a tooth.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Like characters of reference designate like parts in those figures of the 
drawings in which they occur. 
In the drawings: 
The reference numeral 10 indicates the tool, as a whole, which is elongated 
cylindrical in general configuration and symetrical about its longitudinal 
axis. The tool comprises an elongated mandrel 12 coaxially secured to a 
larger diameter elongated handle 14. The other end portion of the mandrel 
12 is tapered, as at 16, to converge toward a substantially conical-shaped 
head end 18 having a selected base diameter less than the diameter of the 
mandrel forming an annular shoulder 20 terminating at its perimeter in a 
hairline edge. The plane of the shoulder 20 is perpendicular to the 
longitudinal axis of the mandrel. The end portion of the mandrel, adjacent 
its connection with the handle, is diametrically reduced, as at 22, for 
the purpose presently explained. 
A generally cylindrical sleeve-like hammer 24 coaxially surrounds the end 
portion of the mandrel adjacent the handle. The bore 26 of the hammer 
slidably surrounds the diametrically reduced portion 22 of the mandrel. 
The hammer is counterbored from its end opposite the handle, as at 28, on 
a diameter slidably surrounding the mandrel. The length of the hammer is 
such that it extends from the hammer end 30 longitudinally toward the head 
end of the mandrel beyond the mandrel diametrically reduced portion 22 
thus forming an annular space 32. The space 32 receives a helical spring 
34 normally urging the hammer toward the handle end surface 30. The hammer 
24 is further characterized by a diametrically enlarged flange 36 at its 
end portion adjacent the handle characterized by opposing arcuate surfaces 
38 and 40 converging outwardly toward the perimeter of the flange. 
OPERATION 
In operation, the dentist manually grasps the handle 14 with his fingers 
surrounding the handle and the end of his thumb adjacent the flange 
surface 38. The mandrel head lip or shoulder 20 is positioned to engage 
the edge of a tooth crown, not shown, projecting toward the gum of a 
patient and while holding the shoulder 20 in this position the hammer is 
manually forced in an axial sliding direction along the mandrel toward its 
head end wherein the dentist slides his thumb outwardly off the arcuate 
flange surface 38 to release the hammer which, by the resilience of the 
spring, is forced toward and impacts against the handle anvil surface 30 
thus imparting a longitudinal jerk or axial movement of the device to 
loosen and/or remove the tooth crown. 
Obviously the invention is susceptible to changes or alterations without 
defeating its practicability. Therefore, I do not wish to be confined to 
the preferred embodiment shown in the drawings and described herein.