Note: Descriptions are shown in the official language in which they were submitted.
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SELF-POSITIONING DENTAL LIGHT FILTERING DEVICE
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a non-provisional patent
application and claims priority from U.S. Provisional
Patent Application Serial No. 61/572,089, filed July 11,
2011.
FIELD OF THE INVENTION
[0002] The present invention generally relates to
dental equipment, and more particularly to dental equipment
used for eye protection.
BACKGROUND OF THE INVENTION
[0003] Various implements have been employed in
dentistry to shield the eyes of the dentist and other care
providers from the optically harmful light emitted from
dental curing devices. The most commonly used implements
are described below.
[0004] One implement comprises a handheld filtering
member that is held over the patient's mouth while the
composite is cured. This is disadvantageous in several
ways. First, the time taken to reach for the filtering
member and hold it in place compromises efficiency since
the dental assistant could be performing other duties while
the dentist is curing. Also, the filtering member can
sometimes be forgotten and not used, leaving the care
provider's eyes vulnerable to the optically harmful light.
Furthermore, the filtering members are typically large and
cumbersome to store and use.
[0005] Another implement comprises a cone that is
placed over the tip of the curing device. However, the
cone can interfere with placement of the tip in the correct
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position, can push matrix systems (which are sometimes
precariously placed) out of their correct positions, and
allows the optically harmful light to leak out of the
perimeter of the cone.
[0006] Still another implement comprises a light
filtering disc that fits over the tip of the dental cure
light, rests near the base of the tip by the light itself,
and is secured to the tip by a grommet or some other
retentive feature. This filtering disc stays outside of
the patient's mouth. The disadvantage of this type of tool
is that it continually needs to be adjusted to get it into
the right position as the curing light is maneuvered around
the mouth. This requires an extra step for the operator or
the operator is forced to lean into a field of view that
allows him/her to see through the filtering disc.
Furthermore, when attempting to cure teeth in the very back
= of the mouth, this type of filtering disc can interfere
with tip placement by pressing against the face of the
patient and need to be adjusted to allow proper tip
placement.
[0007] In summary, all of these implements have
drawbacks and are difficult to use. Some clinicians choose
simply not to use a filtering device because no great
options are on the market. The care providers are
therefore at risk from the optically harmful light. Most
of these clinicians attempt to place the tip in position
and look away from the light while curing. This leads to
inaccuracies in tip placement which sometimes require
another cure in the correct position and/or short exposures
to harmful light if the curing begins prior to looking
away. Thus an opportunity and need exists in the
marketplace for an improved design that overcomes many of
the shortfalls of the aforementioned devices and affords
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dental care providers with an enhanced level of convenience and
protection when using dental curing lights.
SUMMARY
[0008] This relates to a self-positioning dental
light filtering device. In one embodiment, the light filtering
device comprises a transparent filter member for blocking
optically harmful light emitted from a tip of a dental curing
device, and a support for supporting the filter member in an
upright position above the tip of the curing device. The
filtering device also includes a rotational bearing having
concentric outer and inner components rotatable relative to one
another about an axis of rotation. The outer component is
immovable relative to the support and the inner component
defines an opening for receiving the tip or other component of
the dental curing device. A retaining device is provided for
holding the tip or other component of the dental curing device
substantially centered inside the rotational bearing and
substantially rotationally stationary relative to the inner
component of the rotational bearing when the tip or other
component is received in the opening. A counterweight below
the rotational bearing causes the filter member to remain in
its upright position when the tip of the curing device and/or
curing device itself is rotated about said axis of rotation.
[0008a] The invention may also relate to a self-
positioning dental light filtering device, comprising a
rotational bearing having concentric outer and inner components
rotatable relative to one another about an axis of rotation,
the inner component defining an opening for receiving the tip
or other component of a dental light-emitting device, a
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transparent filter member for filtering optically harmful light
emitted from the dental light-emitting device, said filter
member and said inner component of the rotational bearing being
rotatable relative to one another about said axis, and a
counterweight below the rotational bearing for causing the
filter member to remain in an upright position when the inner
component of the rotational bearing rotates relative to the
outer component, as when the tip of the dental light-emitting
device and/or the dental light-emitting device itself is
rotated about said axis of rotation.
[0009] Other features will be in part apparent and in
part pointed out hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
= [0010] Fig. 1 is a perspective of a self-positioning
dental light filtering device of this invention;
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[0011] Fig. 2 is a side elevation of the light
filtering device of Fig. 1 mounted on the tip of a dental
curing device;
[0012] Fig. 3 is a front elevation of the light
filtering device of Fig. 1;
[0013] Fig. 4 is an enlarged vertical section taken in
the plane of 4--4 of Fig. 3; and
[0014] Fig. 5 is an exploded assembly view of the
light filtering device showing various components.
[0015] Corresponding reference characters indicate
corresponding parts throughout the drawings.
DETAILED DESCRIPTION
[0016] Referring now to the drawings, Fig. 1
illustrates one embodiment of a self-positioning dental
light filtering device of this invention, generally
designated 10. The light filtering device 10 is configured
to be mounted on the tip or other component of a dental
curing device for blocking optically harmful light emitted
from the tip of the device. A conventional dental curing
device, generally designated 20, is depicted in phantom
lines in Fig. 2. The curing device has a body 22 formed as
a handle to be gripped by the care provider (e.g.,
dentist), and an elongate tip 24 extending forward from the
body. The body 22 is equipped with a light-emitting device
26, such as an LED, that emits a curing light 28 through
the tip 24, as will be understood by those skilled in the
field of dentistry. Typically, the tip 24 can be rotated
(manually) relative to the body 22 of the curing device 20
about the longitudinal axis 29 of the tip. The curing
device 20 forms no part of this invention and will not be
described in further detail.
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[0017] The light filtering device 10 comprises a
transparent filter member 30 of a color, tint or material
for blocking optically harmful light 28 emitted from the
tip 24 of the dental curing device 20, and a support,
generally designated 32, for supporting the filter member
in an upright position above the tip 24 of the curing
device 20. The light filtering device 10 also comprises a
bearing mount, generally designated 36, affixed to the
support 32. The bearing mount 36 supports a rotational
bearing, generally designated 40, having concentric outer
and inner components 42, 44 (Fig. 4), which are rotatable
relative to one another about an axis of rotation 46. The
outer component 42 is immovably affixed to the bearing
mount 36. The inner component 44 defines an opening 38
(Fig. 5) concentric with the axis of rotation 46 for
receiving the tip 24 of the curing device 20. A retaining
device, generally designated 50, is provided in the opening
38 for holding the tip 24 of the curing device 20
substantially centered with the rotational bearing 40
(i.e., concentric with the axis of rotation 46 and also
concentric with the longitudinal axis 29 of the tip) and
substantially rotationally stationary relative to the inner
component 44 of the rotational bearing 40 when the tip is
received in the opening 38. A counterweight, generally
designated 60, located below the rotational bearing 40
causes the filter member 30 to remain in its upright
position when the tip 24 of the curing device 20 or the
curing device 20 is rotated (by the care provider) about
the axis of rotation 29. The components of the light
filtering device 10 are described in more detail below.
[0018] The filter member 30 illustrated in the
drawings is generally oval in shape, but it may have other
shapes (e.g., circular, rectangular, polygonal) without
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departing from the scope of this invention. The filter
member is of a material suitable for blocking harmful
curing light 28 emitted by the curing device 20, which
curing light typically is a blue light having a wavelength
in the range of 450-500 nm. By way of example but not
limitation, the filter member 30 may be of cell-cast
acrylic. This type of acrylic is resistant to chemicals
and has the desirable property of being transparent to
allow optical clarity. One suitable color, amber 2422, is
commonly available in the industry and is suitable for
filtering the curing light 28 so that it is safe for
viewing.
[0019] The oval shape of the filter member 30 allows
for a small connection to the bearing and a larger viewing
section in the superior position for eye protection.
Desirably, the filter member 30 is of relatively thin sheet
material (e.g., 1/32 in. sheet material, referred to the
industry as .030 in. sheet). The relatively thin material
is desirable to minimize the weight of the filter member 30
and offsetting counterweight 60.
[0020] Referring to Fig. 4, the support 32 has an
upper generally planar section 32A disposed above the
rotational bearing 40 and a lower generally co-planar
section 32B disposed below the rotational bearing. The
upper and lower sections 32A, 32B lie in a first plane P1
generally perpendicular to the axis of rotation 46 and
define a circular opening 62 that is generally concentric
with the opening 38 in the rotational bearing 40 and about
the same size as that opening. The filter member 30
extends from the support 32 and lies in a second plane P2
oriented at an angle A relative to the first plane Pl.
Desirably, this angle A is in the range of plus or minus 0-
60 degrees, and even more desirably in the range of plus or
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=
minus 0-20 degrees. In one embodiment, the support 32 and
filter member 30 are integrally formed as one piece from
the same material (e.g., cell-cast acrylic), but they may
be formed as separate pieces of the same or different
material and then attached to one another.
[0021] The support 32 and/or filter member 30 can have
configurations other than those described above without
departing from the scope of this invention.
[0022] Referring to Figs. 4 and 5, the bearing mount
36 comprises a curved member 69 immovably affixed to one
face 68 of the upper section 32A of the support 32 and at
least partially surrounding the outer component 42 of the
rotational bearing. The curved member 69 has an upper
surface 70 and a curved (e.g., semi-circular) lower surface
72 closely conforming to the curvature of the outer
component 42 of the rotational bearing. At least the lower
surface 72 and desirably both the upper and lower surfaces
70, 72 are generally concentric with the axis of rotation
46. By way of example, the curved member 69 may be a part-
circular section (e.g., semi-circular section) of acrylic
tubing adhered to the support 32. The bearing mount 36 may
have other configurations without departing from the scope
of this invention.
[0023] In the illustrated embodiment, the rotational
bearing 40 is a thin-section rolling-element bearing, such
as a bearing commercially available from, for example,
Alpine Bearing Co. in Allston, MA. The outer component 42
of the bearing comprises an annular outer race, also
designated 42, immovably affixed (e.g., adhered) to the
curved lower surface 72 of the bearing mount 36 and to the
counterweight 60. The inner component 44 of the bearing
comprises an annular inner race, also designated 44, having
an inside diameter defining the tip opening 38. Balls or
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other roller elements 80 positioned between the two races
42, 44 allow relative rotation between the inner and outer
bearing components. The inside diameter (ID) of the inner
annular race 44 is relatively close to the outside diameter
(OD) of the outer annular race 42. By way of example, the
difference between the ID and OD may be about 0.125 in. or
less. A thin-section rotational bearing allows the bearing
to be relatively small yet have a relatively large opening
sufficient to accommodate the retaining device 50 and
curing devices having tips of varying diameter. The
bearing 40 is lubed with an oil of a viscosity that
provides the right amount of movement without being too
stiff. Other types of rotational bearings may also be
used.
[0024] Referring to Figs. 3-5, the retaining device 50
comprises a ring 90 fitted inside the tip opening 38
defined by the inner component 44 of the rotational
bearing. The ring 90 defines a central opening 92
concentric with axis 46 (see Fig. 4). Resilient tapered
gripping members 94 extend inward into the opening 92 for
gripping the tip 24 of the dental curing device 20. The
ring 90 includes a pair of annular flanges 96 projecting in
a generally radial direction outward from the ring. The
flanges 96 are spaced apart to define an annular groove 98
between the flanges for receiving the inner race 44 of the
bearing 40. Desirably, the ring 90 and gripping members 94
are integrally formed (e.g., molded) as a one-piece
structure of resilient material. The ring 90 is sized for
a snap fit of the inner race 44 of the bearing 40 inside
the groove 98. By way of example but not limitation, the
ring 90 and gripping members 94 may be formed from 70-
durometer rubber, which is rigid enough for securely
holding the device 10 on the tip 24 of the curing device 20
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but not so rigid that the tip cannot be easily snap-fit
inside the rotational bearing 40. Further, the resilient
nature of the retaining device 50 allows it to accommodate
light tips 24 (or other curing device components) having
substantially different diameters falling within a
relatively wide range of sizes. The retaining device 50
may have other shapes without departing from the scope of
this invention.
[0025] Referring to Figs. 4 and 5, the counterweight
GO comprises a curved counterweight member 100 immovably
affixed (e.g., adhered) to face 68 of the lower section 32B
of the support member 32 and to the lower surface of the
outer component 42 of the rotational bearing 40. The
counterweight 60 is of a suitably heavy material, such as a
tungsten alloy, a very dense yet non-toxic metal which
minimizes the size of the counterweight. By way of
example, the alloy may have a density in excess of 18 g/cm3.
Desirably, the counterweight member 100 has a curved
generally part-circular upper surface 102 that wraps around
and closely conforms in size and shape to the curved lower
surface of the outer annular 44 race of the rotational
bearing 40. (The outer race 44 is adhered to this surface
102.) The counterweight member 100 also has upward-facing
end surfaces 104 that desirably seats against and are
immovably affixed (e.g., adhered) to downward-facing end
surfaces 106 of the bearing mount 36. The lower surface
110 of the counterweight member 100 tapers in a direction
away from the support 32 to facilitate partial entry into
the mouth of a patient, as needed or desired.
[0026] The counterweight 60 may have other shapes and
be placed at other locations on the support member 32
without departing from the scope of this invention.
Further, while the illustrated counterweight comprises only
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=
one member, the counterweight can include two or more
separate members.
[0027] The overall weight of the counterweight 60 is
sufficient to offset the weight of the filter member 30 and
maintain it upright as the tip 24 is turned and/or when the
body 22 of the curing device 20 is rotated into position.
By way of example, this weight may be in the range of 5-40
grams, and even more particularly in the range of 15-25
grams. Desirably, the counterweight 60 is positioned
close enough to the rotational bearing 40 to prevent
rocking as the filter member 30 approaches a resting
position as determined by the counterweight. In the
illustrated embodiment, the counterweight 60 is located
immediately adjacent the rotational bearing 40, with the
counterweight and rotational bearing spaced apart a
distance no greater than 0-0.125 in. This location reduces
the overall size of the light filtering device 10 for
maximum compactness and also minimizes any pendulum-like
rocking of the filter member 30 when the tip 24 or curing
device 20 is rotated or repositioned by the care provider.
However, the counterweight 60 can be located more remotely
from the rotational bearing 40 without departing from the
scope of this invention.
[0028] The components of the light filtering device 10
described above may be adhesively bonded together using a
DP 190 epoxy available from 3M Company. It is clear for
good esthetics, has a very high bond strength at room
temperature, and is not brittle (making it flex slightly if
the device is dropped to avoid breaking the adhesive bond).
[0029] In use, the light filtering device 10 is
installed on the tip 24 of the curing device, as
illustrated in Fig. 2. As thus installed, the retaining
device 50 grips the tip 24 and holds it substantially
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concentric with the axis of rotation 46 and rotationally
stationary relative to the inner component 44 of the
rotational bearing 40. Thus, when the care provider
rotates the tip 24 of the curing device 20 and/or rotates
or repositions the curing device itself during a procedure,
the retaining device 50 and the inner component 44 of the
rotational bearing 40 will rotate with the tip relative to
the outer component 42 of the rotational bearing immovably
offered to the support 32. The counterweight 60 functions
to keep the filter member 30 upright and in proper position
during the procedure to block curing light 28 emitted from
the light-emitting device 26, regardless of how the tip 24
is turned, the patient is turned or tilted, or how the
curing device is rotated. In effect, the light filtering
device 10 "self-positions" during the procedure to remain
in the proper upright orientation, without the need for any
adjustment or repositioning by the care provider or other
person.
[0030] It will be observed that the primary movement
of the body 22 and tip 24 of the curing device 20 is
rotational as the clinician determines the correct
position. Sometimes during use the body 22 of the curing
device 20 may be rotated one way and the tip 24 grasped and
rotated in an opposite direction to reach the desired spot
in a patient's mouth. Having a filter member 30 that
maintains its upright position during these movements
creates operational efficiency. In view of the rotational
movements of the body and light tip of the curing device,
the rotational bearing 40 positioned in the plane of these
movements facilitates auto-positioning of the device. This
arrangement also allows the light tip to protrude through
the inside of the bearing.
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=
[0031] As noted above, a light filtering device 10 of
this invention permits operational efficiencies. By way of
example, a clinician curing a composite resin does not need
to hold the curing device 20 with one hand and rotate the
filter member 30 with the other to achieve the correct
position; one hand is adequate. Also, if the position of
the filter member 30 needs to be rotated slightly, it is
easily done with a nudge with either hand. The body 22 of
the curing device 20 does not need to be grasped tightly to
rotate the filter member 30. Still further, using the
light filtering device 10, only one individual is needed to
cure the composite.
[0032] Having described the invention in detail, it
will be apparent that modifications and variations are
possible without departing from the scope of the invention
defined in the appended claims.
[0033] When introducing elements of the present
invention or the preferred embodiments(s) thereof, the
articles "a", "an", "the" and "said" are intended to mean
that there are one or more of the elements. The terms
"comprising", "including" and "having" are intended to be
inclusive and mean that there may be additional elements
other than the listed elements.
[0034] In view of the above, it will be seen that the
several objects of the invention are achieved and other
advantageous results attained.
[0035] As various changes could be made in the above
constructions without departing from the scope of the
invention, it is intended that all matter contained in the
above description and shown in the accompanying drawing[s]
shall be interpreted as illustrative and not in a limiting
sense.
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