Note: Descriptions are shown in the official language in which they were submitted.
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BEGO Semados GmbH, Wilhelm-Herbst-Stra(3e 7 , 28359 Bremen
Dental implant driver assembly with a dental implant
and a receptacle and installation tool for same
The invention relates to ar~~~ implant driver assembly and dental implant for
securing dental prostheses to tile jaw, wherein the implant is joined by means
of
a centric screw connection tc~ an insertion post that has a means for being
held
in a concentric receptacle surrounding the implant, said rrreans comprising a
cylindrical portion and an adjoining st,oulder located in the direction of
withdrawal, which latter shoulder can form a frictional contact with an
annular
collar of the receptacle, whereby adjoining said shoulder :in the direction of
withdrawal there is a portion of the insertion post that can engage with both
a
non-rotating interlocking fit as well as axial frictional andlor interlocking
engagement with a tool for inserting the implant. The invention relates also
to
such a receptacle, and installation tool and to a rnethod for removing the
implant
driver assembly from the recE:ptacle and fof installing the implant in the
jaw.
In a prior art implant driver assembly, the insertion post comprises a
component
having an O-ring between two annular collars approximately in the center of
its
longitudinal extension,. said C)-ring extending radially beyond said annular
collars
and sealing them against a tubular recr:ptac:le closed at one end when it is
inserted into same. The annular collar open to the closed end of the
receptacle is
followed by a cylindrical member having a larger c9iameter than that of the
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implant, which is pulled againat the screw sunk inside the insertion post by
same
screw; the member also serves as a guide for a tube surrounding it and the
implant, which tube is held bc:etLVeen the annular collar adjacent said member
and
the closed end of the receptaclf:, and which protects the implant in
particular
during any form of transportatiar~ until the implant driver assembly is
withdrawn
from the receptacle. Like the insertion past (and the irnplant itself), the
tube is
made of titanium, a costly material.
When the implant driver assembly is received by the receptacle, the other
annular collar is located adjacent the open end of said receptacle. The
annular
collar is connected above all to a portion that is appropriate for receiving a
wrench (such as an Allen wrench) with which it: can be non-rotatably engaged;
said portion is already located within the receptacle. Untie such time as the
implant is to be installed, the receptacle is inserted, along witty the
implant driver
assembly that is located within it but with a portion of the insertion post
extending outside it, into a similarly tubular transport housing that, like
the
receptacle, is made of plastic. Said transport housing is tubular in shape
also, and
closed at one end, whereas the other end is closed by a cover that cart be
released but which is sealed until use. At the bottom of the transport
housing,
between said housing and the bottom of the receptacle, there is a similarly
vessel-shaped holder for the screw plug that seals the location hole for the
dental prosthesis when the implant is screwed into it, until such time as the
implant has integrated with the l:aane.
This prior art method for accommodating and holding the implant driver
assembly
in the receptacle and for accommodating the fatter in the transport housing
has
proved itself in practice, but fails to meet all requirerrtents. One aspect is
that: the
material costs far the inserti~:3n post, a disposable product, are relatively
high.
Another problem is that thca design desnribed in the foregoing requires the
insertion post to have a large diameter, vvhicha makes it difficult or even
impossible to screw in the irxrplant with the insertion post, especially when
teeth are close together. A firtall aspect is that the tube for protecting the
implant
is also a disposable product that causes additional expense an account of the
expensive material of which it is made; rnareover, removing the implant driver
assembly from the receptacle (after aEtening the external housing) involves
several steps thal: prolong the tune needed by the dentist to install the
implant,
and increases the risk of the anaesthetic wearing off. In addition to these
aspects,
sterilization of the implant ca river assemttly is confined to the space in
the
receptacle under the O-ring, winereas that part of the insertion post on the
other
side of the O-ring is not sterilized; furthermore, there is a risk that
sterilization of
the implant portion is reversed because of ieakages past the O-ring. Yet
another
aspect is that thE: screw plug is similarly Ioc:atE:d outside the receptacle
within the
outer housing.
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The dental implant driver described above is also known in a form 'with
receptacle from US P S 5 062 800. The latter invention comprises a cylindrical
tube, closed at the bottom, a:rgainst the open upper end of which a shoulder
of
an insertion post can engage. This requires that the shoulder have a
relatively
large diameter (making it accordingly difficult to handle the insertion postl.
Furthermore, it does not perrrnit the space around the implant, which space
rnust
be kept sterile, to be sealed independently of the insertion post.
The invention aims to solve these problems. It consists in the annular collar
being formed by a radially reduced constrictive portion of t:he receptacle
that
narrows the diameter of the receptacle (3? to a slightly larger diameter than
the
cylindrical portion, and said a:ylindrical portion h<~ving a slightly larger
diameter
than that of the implant.
The resultant implant driver assembly is. slim throughout, and its greatest
diameter - namely that of this shoulder - exceeds the diameter of the implant
to
a minimal extent only; it can be removed with the help of the tool that is
frictionally attached over the top of the insertion post, and can be guided
directly to the hole bored in the jaw due to the non-rotatable engagement that
is
simultaneously provided. There are no portions of the insertion post that
extend
radially beyond the implant, whric:h could collide with adjacent teeth when
teeth
a close together. In addition; the amount of costly materials for the
insertion
post, which can be used or7cte only, is reduced to a minimum; the protective
tube used in the prior art is oty:wiated entirely.
Particularly advantageous is the co-operation of the implant driver assembly
according to the invention with a receptaclE~ comprising a tube that can be
closed
at the ends by stoppers and which is constricted radially about its
circumference
at the portion where the diameter is reduced. The portion of the tube with
constricted diameter receives the cylindrical portion of the insertion post,
and
connects at its one end to the: shoulder adjoining said cylindrical portion,
so that
the implant driver assembly is securely held in the receptacle when the
withdrawal end of the tube is closed by a stopper that preferably has a
centric
recess that is open to the insic9e of the tube and surrounds, in the receiving
state, the end portion at the witi~drawal end of the insertion post.
It is advantageous that the receptacle tube is made of glass, a material known
to provide advantages in respf:;ct of sterilization. It car? also be closed by
a stopper
at the end opposite to the withdrawal end, and said stopper preferably has a
recess open to the inside of the tube for accepting a screw plug 'for the
implant.
In this way, the entire implant driver assembly as well as the screw plug are
in
the sterilized portion. For transportation purposes, the receptacle is
conventionally surrounded kay a transport housirng with a closeable cover.
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However, it is also possible t:o make the receptacle out of plastic or metal,
for
example titanium.
A tool such as that invented here for withdrawing and screwing in the new
implant driver assembly comprises a tubular portion with a hex key socket at
the
open end of the inside wall and adjacent a tubular diameter that produces
frictional engagement with the end portion of the insertion post when they are
brought into contact. This provides a simple means for ensuring that the
connection between the installation tool and the insertion post when
withdrawing
the implant driver assembly franc the receptacle is kept non-rotational and
a~t the
same time axially frictional. Tle irostallation tool may also comprise further
portions with cross-sectional configurations for attaching wrenches, such as
ratchets and the like, or indeed an internal screw thread for attaching a
rotary
table.
The method of the invention for inserting a screw implant consists in the end
portion of the installation tcaol being guided over the insertion post after
the
sealing stopper at the withdrawing end of the receptacle is removed and in the
complementary hex portions being bought into contact with each other against
the friction between the tool end portion arid the inside wall of the tube,
that the
implant driver assembly with the tool is then pulled out of the receptacle and
screwed into 'the jaw (in wloich a hole has been fore-bored), after which the
screwed connE;ction betweer-~ tfae implant and the insertion post is released
and
the insertion post is pulled off.
The drawing illustrates an embodiment of the invention, whereby:
Fig. 1 shows an enlarged view, in central axial secaion, of an implant
driver assembly (including screw plug) inserted in a receptacle
and <~ transport housing;
Fig. 2 shows an caxtraction tool in a more enlarged side view, cross-
section and plan view; and
Fig. 3 shows the sequence for removing the implant driver assembly
from the receptacle.
A receptacle, referred to in its entirety as 3, is located in a transport
housing 1
made for example of t ransparerrt plastic, which housing is closed by means of
a
stopper (also made of plastic) that is sealed in the usual manner. The
receptacle
comprises a glass tube 4, tire two open ends of which are closed by means of
sealing stoppers 5 and 6, re:~pectively. Receptacle 3 contains the implant
clriver
assembly comprised of the insertion post -7 and the implant ~.
The screw implant 8 is joined with the generally tubular insertion post 7 by a
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screw 9 inside said insertion post, the thread of the screw engaging with the
internal screw thread 10 provided; after insertion of implant 8 in a patient's
jaw,
the latter screw thread serves to accept t+~e thread of a screw plug 11 that
is
contained and held ready in a recess 12 of the sealinc3 stopper 6.
Insertion post 7 has a centering collar 13 at one end that fit into and
engages
implant 8, and a cylindrical t:rortion 14 extending in the direcaion of
withdrawal
from said collar to an adjoining shoulder 15. In the inserted status (as
illustratedl,
the cylindrical portion 14 is Ic>cated within a throat 16 of tube 4, said
throat
being formed by a narrower portion 17 of the tube. Shoulder 15 is situated
above
throat 16 against the narrowed wall portion of tube 4.
Further along irr the direction ,cf withdrawal, shoulder 15 is followed by a
portion
18 of insertion post 7 comprising a hex N;ey socket 19 and an end portion 20
with a lengthwise slot (slot 21 ). Said end portion has a ring-shaped
enlargement
22 of its diameter at its open end.
When the implant 8 is to be ir7serted and fastened in a jaw, cover 2 is first
removed from the transport Frousing -- by breaking seal 23 - and receptacle 3
is
taken out (Fig. 3 a). Receptacle 3 is then opened by removing sealing stopper
5,
and pursuant to Fig. 3 b an installation focal in the form of the insertion
key 24,
shown in considerable enlargement in Fig. 2, is guided over portion 18 of
insertion post 7, which continues remains held as implant driver assembly with
implant 8 in tube 4 (in Fig. 3 k:; r~ rotary tale has already been screwed
into the
insertion key 24). Hex key socket 19 of ir~sertian post 7 ernclages thereby
with
the tubular portion 26 of inse:rticar~ key 24, which has a hexagon nut fitting
hex
key socket 19 on the inside ~of its open errd. At the same time, the ring-
shaped
thicker part 22 around the c;irc:c.n-nference at the open end of insertion
post 7
attaches, due t:o the carrespr~nding diameters, to the slightly stepped
portion 28
of the inner wall of tubular pc:artion 26 of insertion kc;y 24, adjoining
hexagon nut
27. The friction<31 engagement. thus engendered between insertion post 7 and
insertion key 24 allows the irrrplant driver assembly to be withdrawn by the
Fatter
in an axial direction from tube= 4 of receptacle 3 (Fig. 3 dl. Without needing
any
intermediate step, the impl~:~nt 8 can then be screwed into the fore-bored
jawbone, either mam_rally uainc3 a wrench (ratchet or the like) placed over
portion 29 of insertion key 2~~ (Figs. 2. b arid c), with the help of the
rotary liable
25, or by mechanical means.
When the implant has been screwed in, screw 9 connecting implant 8 with the
implant driver assembly is released using a suitable hex key and removed. This
is
done by taking insertion ke~r 24 out of ;nsertion post 7; however, it is also
possible - where relevant, after removing rotary table 25 from the internal
screw
thread 30 of insertion key 2~I - to engage the key for screw 9 through
insertion
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key 24 with screw 9 and to null off insertion post 7 together with insertion
key
24 from the fastened implant 8. in a final step, screw plug 11 is removed from
recess 7 in stopper 6 and screwed into the internal screw thread 10 of implant
8,
in order to protect thread 10 ,:end keep it clean until such later time -
after implant
8 has become integrated witlo the jaw - w,~hen the dental prosthesis is
screwed
onto the implant.
