Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS3905109 A
Publication typeGrant
Publication date16 Sep 1975
Filing date22 Mar 1974
Priority date22 Mar 1974
Publication numberUS 3905109 A, US 3905109A, US-A-3905109, US3905109 A, US3905109A
InventorsCohen Bernard D, Zeewy Abraham
Original AssigneeCrysta Dent Inc
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Dental implant member
US 3905109 A
Abstract
A dental implant member for supporting and stabilizing crowns, bridges, or the like, having a threaded portion to be received in the alveolar bone, a cylindrical section to be embraced by periodontal tissue, and a conical frustum section to be received in a suitable opening in the crown, terminal pontic of a bridge, or the like.
Images(2)
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

United States Patent 1 Cohen et al.

[451 Sept. 16, 1975 DENTAL IMPLANT MEMBER [75] Inventors: Bernard D. Cohen; Abraham Zeewy,

both of Cleveland, Ohio [73] Assignee: Crysta-Dent, Inc., Cleveland, Ohio [22] Filed: Mar. 22, 1974 [21] AppL No.: 453,711

[52] US. Cl. 32/10 A; 32/10 A [51] Int. C1. A61C 13/00 [58] Field of Search 32/10 A [56] References Cited UNITED STATES PATENTS 4/1969 Brancato 32/10 A 9/1969 Christensen 32/10 A 5/1971 Stevens 32/10 A 3,589,011 6/1971 Sneer 32/10 A 3,787,900 1/1974 McGee 32/10 A FOREIGN PATENTS OR APPLICATIONS 49,639 1/1889 Germany 32/10 A Primary ExaminerRobert Peshock [5 7 ABSTRACT A dental implant member for supporting and stabiliz ing crowns, bridges, or the like, having a threaded portion to be received in the alveolar bone, a cylindrical section to be embraced by periodontal tissue, and a conical frustum section to be received in a suitable opening in the crown, terminal pontic of a bridge, or the like.

4 Claims, 6 Drawing Figures PATENTEU 1 75 SHEET 2 BF 2 FIG. 4

DENTAL IMPLANT MEMBER This invention relates to the field of dental prosthetics, and more particularly, to an improvement in-dental implant members.

BACKGROUND OF THE INVENTION lmplantology involves the embedment of one or more artificial support and stabilizing implant members in the alveolar bone portion of the jaw to. act as an artificial root fora prosthetic tooth, e.g., a crown, or a series of connected prosthetic teeth, e.g., a bridge.

This technique is to be distinguished from the conventional crown procedure wherein the ground-down stub of a viable tooth is used as the support structure.

The implantology technique is to be distinguished, also, from the conventional technique for preparing a bridge wherein the prosthetic device is-c1amped to adjacent sound tooth structure for support and stabilization.

vIn general, an implant member will be employed to support a crown where the stub of a natural tooth is not available, and it will be used to support a bridge where it is not possible or is undesirable to anchor the prosthetic device to the natural-tooth next adjacent to the gap to be bridged, and where such a natural tooth is absent.

The use of implant members enables the dentist to develop prosthetic devices which are self-contained, and self-supporting, and which do not require the presenceof adjacent natural teeth. Further, prosthetic devices supported by implant members are generally lighter in weight than varieties which are supported by adjacent natural teeth, more comfortable to wear, and are aesthetically more pleasing since they are free of visible metal clamps and the like.

A variety of dental implant members have been proposed and experimented with. These include devices in the forms of blades, pins, screwsand the like. For one reason or another, none of these devices has as yet met with substantial commercial success. For example, blade-shaped implant members require extensive surgery to install, and this is accompanied, necessarily, by substantial trauma. Pins, although easier to install, frequently provide inadequate long term support and stabilization because of their relatively small cross-section and poor anchoring ability.

In some respects, the screw-type implant members have the capability of providing a reasonable compromise between the blade and pin-type implant members. They provide better anchoring than do pin implant members, and can be installed with far less extensive surgery and attendant trauma associated with bladetype inserts.

However, the screw-type insert members developed to date have not lived up to their potential. One of the problems associated with prior art screw-type implant members is that they tend to promote irritation, inflammation and infection of the periodontal tissue; This is believed to be due at least in part to the manner in which the implant members are designed in the area in which they contact the periodontal tissue. A contributing factor maybe tissue rejection of the material forming the implant member.

Another problem associated with prior art screwtype implant members is that consideration has not been given to designing their shank portions to accommodate crowns and bridges in a manner which allows for proper fit. Failure to do so can result in non-axial stresses being applied to the implant members, for example, through chewing. The resultant stresses can effect a loosening of the implant member and eventual failure of the crown or bridge it supports.

SUMMARY OF THE INVENTION It is a principal object of the present invention to overcome the foregoing problems by providing an improved dental implant member of the screw-type which will not irritate periodontal tissue, and which, in general, will provide a stronger and sturdier support structure for dental prosthetics than screw-type implant members of the prior art. This can be accomplished with nominal clinical instrumentation used to perform a simplified surgical technique with minimal trauma resulting.

in accordance withthe present invention, there is provided a dental implant member formed of a generally cylindrical body, comprising a threaded portion having upper and lower ends. The threaded portion is defined by a plurality of thread convolutions terminating radially of the body in thread crests, and separated axially along the body by thread flanks.

The implant member is further provided with a shank portion having an upper end, and a lower end coterminus with the upper end' of the threaded portion.

The shank portion comprises a cylindrical section defining the lower end of the shank portion and extending upwardly a distance within the range of from about 0.5 to about 1.5 mm. or greater, but preferably about 1 mm. from the terminus of the upper thread flank of the uppermost thread convolution defining the threaded portion of the implant member. The periphery of the cylindrical section and the thread crests are designed to lie in a plane parallel to the axis of the generally cylindrical body of which the implant member is formed.

Finally, the shank portion further comprises a conical frustum section having its base coterminus with the upper end of the cylindrical section of the shank portion of the implant member. As described more fully hereinafter, the conical frustum section is provided with means for drivingly connecting the implant member with an inserting tool.

In accordance with a further aspect of the present invention, the dental implant member is formed of a ceramic composition comprising at least about 95 wt. aluminum oxide. This material is preferred due to its inertness and its compatibility with living tissue.

An important feature of the invention is the provision of the shank portion of the implant member with a cylindrical section. When the implant member is screwed into the alveolar bone, the cylindrical section of the shank portion comes to rest in the plane of the periodontal tissue, which is then able to conform itself smoothly and uniformly to the constant radius of curvature of the said cylindrical section.

Another important feature of the invention is the provision that the thread crests and the periphery of the cylindrical section lie in a plane parallel to the axis of Another important feature of the invention is the provision of a conical frustum section on the shank portion, which coacts with a generally cylindrical opening in a crown or terminal pontic of a bridge, to permit the prosthetic device to be canted or angled to provide the best fit and minimize non-axial stresses in the implant member which would ultimately weaken its anchorage in the alveolar bone.

BRIEF DESCRIPTION OF THE DRAWINGS Referring now to the drawings wherein like reference numerals indicate like parts of the various views:

FIG. 1 is a pictorial schematic view of a dental implant member of the present invention;

FIG. 2 is a schematic cross-sectional view of a fragment of a jaw into which has been set a six-pontic bridge in which the terminal pontics are supported by implant members of the present invention;

FIG. 3 is a schematic cross-sectional view of a crown installed with an implant member of the present invention;

FIG. 4 is a pictorial schematic fragmentary view of a jaw into which a hole is about to be drilled;

FIG. 5 is a pictorial schematic fragmentary view of a jaw having a drilled hole which is about to be tapped; and

FIG. 6 is a pictorial schematic fragmentary view of a jaw into which an implant member has been screwed, using an insert tool.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, FIG. 1 illustrates dental implant member A formed of a generally cylindrical body, and comprising threaded portion B and shank portion C.

Threaded portion B has upper and lower ends l0, 12 respectively, and is defined by a plurality of threaded convolutions terminating radially of the cylindrical body in thread crests I4, and separately axially along the body by thread flanks I6.

Shank portion C has an upper end 18 and a lower end coterminus with upper end of threaded portion B.

Shank portion C further comprises cylindrical section 20 defining the lower end of the shank portion and extending upwardly a distance within the range of from about 0.5 to about 1.5 mm. or greater, but preferably about 1 mm., from terminus 22 of upper thread flank 16 of the uppermost thread convolution defining threaded portion B. Shank portion C further comprises conical frustum section 24 having its base coterminus with the upper end of cylindrical section 20.

Upper end 18 of shank portion C is provided with means for drivingly connecting the implant member with an insert tool (see FIG. 6), which, in the embodiment illustrated in FIG. 1, takes the form of opposed, generally flat, parallel faces 26.

Referring to FIG. 2, there is illustrated a portion of ajaw, designated generally as 30, comprising periodontal tissue 32 and alveolar bone 34.

Mounted in thejaw is bridge 28 comprising interconnected pontics 36, 38, 40, 42, 44, 46.

Terminal pontics 36, 46 are provided, respectively, with generally cylindrical bores 48, 50 into which conical frustum sections 24 of implant member A are set in suitable cement 52.

It will be noted that cylindrical section 20 of the shank portion of implant member A is generally coplanar with periodontal tissue 32. This provides the tissue with a smooth, uniform surface of constant radius of curvature to lie against, minimizing the chances of irri tation developing. Essentially, the entire length of the threaded portion B of the implant member is embedded in alveolar bone 34.

It should be particularly noted that in order to provide a proper fit for bridge 28, conical frustum section 24 is generally centered within cylindrical bore 48 of terminal pontic 38, while conical frustum section 24, upon which terminal pontic 46 is mounted, is disposed eccentrically within cylindrical bore 50. If not for the ability to accommodate the alignment of the terminal pontics on their respective implant members, undue stresses would be set up in the implant members which would ultimately weaken their anchorage in alveolar bone 34.

FIG. 3 illustrates the mounting of crown 54, a single tooth prosthetic device, on implant member A. It will be seen from this illustrated embodiment that the implant member of the present invention can be used to support and stabilize a single tooth prosthetic device as well as a bridge as described above.

The implant members may be formed of any of a variety of different materials so long as they are sufficiently strong to meet the support and stabilizing demands placed upon the insert and are inert to the environment in which the inserts are to be placed. Among the useful materials are synthetic organic resins, with and without structural fillers and reinforcement; metals and alloys; and ceramic compositions. Vitallium, a commercially available cobalt-based alloy, is a suitable metallic material for use in practicing the invention. Useful ceramic materials will contain at least wt. aluminum oxide and preferably at least about 96 wt. aluminum oxide. A useful commercially available ceramic material is sold under the trademark Degussit (believed to contain about 99.5 wt. aluminum oxide) manufactured by Degussa, a German company.

The method of installing a dental implant member of the invention is pictorially illustrated in FIGS. 4 6.

Referring to FIG. 4, after periodontal tissue 32 is reflexed, drill -bit 56, driven by suitable means not illustrated, is lowered into alveolar bone 34 to a depth corresponding approximately to the length of the threaded portion of the implant member to be installed. A suitable stop means, such as sleeve 57 illustrated in FIG. 4, may be attached to drill bit 56 to mark the desired depth. The diameter of drill bit 56 should be slightly less than the diameter of the cylindrical body from which the implant member is formed. For example, if the diameter of the cylindrical body is 0.134 inch, the diameter of the drill is conveniently 0.125 inch.

After the hole has been drilled and the drill bit removed, the hole is then tapped with tap 58 to which insert tool 60 is drivingly connected, as illustrated in FIG. 5. The diameter of the tap should be slightly larger than the diameter of the cylindrical body forming the implant member. Thus, where the cylindrical body is 0.132 inch in diameter. a suitable tap would have a diameter of (l. 138 inch.

After the hole has been tapped and the tap removed, dental implant member A, as illustrated in FIG. 6, is then inserted in the hole and screwed into place with insert tool 60 which, for the sake of convenience. is the same tool used to drive tap 58. Tool 60 is provided with flats 62 which are suitably dimensioned to snugly fit against surfaces 26 formed in the conical frustum section of dental implant member A (The same flats 62 fit snugly against surfaces 26a formed in the shank portion of tap 58, as illustrated in FIG. 5). The reflexed periodontal tissue is then returned to its normal position and stitched as may be necessary to close the incisions.

After the one or more implant members have been installed and the incisions permitted to heal, the prosthetic device, be it a crown or bridge, is then installed using a suitable cement as illustrated in FIGS. 2 and 3.

Modifications of the implant member illustrated in the preferred embodiment will readily suggest themselves to those skilled in the art. For example, surfaces 26 may be replaced with a variety of other means for accepting suitably designed insert tools, e.g., a slotted head, or a transaxial bore through frustum conical section 24.

It will also be understood that in the practice of the present invention, it is contemplated that dental implant members of varying lengths and diameters will be required to satisfy a full range of implant conditions. For purposes of illustration only, and without intending to limit the scope of the invention, a typical implant member will have the following dimensions:

LENGTH Shank Portion .315 in. Cylindrical Section .040 in. Threaded Portion .394 in.

DlAMETER (OVERALL) .l34 in.

THREADED PORTION Thread pitch 20 Major diameter .134 in. Minor diameter .102 in. Width of flat at crest .008 in. Leading flank angle 45 Trailing flank angle 14 30 While the invention has been described with reference to certain specific embodiments, neither the embodiments illustrated nor the terminology employed in describing them is intended to be limiting; rather it is intended that the scope of the invention be limited only by the terminology of the appended claims.

Having thus disclosed our invention, We claim:

1. A dental implant member formed of a generally cylindrical body consisting of a. a threaded portion adapted to lie in bone having upper and lower ends, said threaded portion defined by a plurality of thread convolutions terminating radially of said body in thread crest and separated axially along said body by thread flanks, and

b. a shank portion having an upper end, and a lower end coterminus with the upper end of said threaded portion, said shank portion consisting of:

i. a cylindrical section adapted to lie in tissue defining the lower end of said shank portion and extending upwardly a distance of at least about .5 mm. from the terminus of the upper thread flank of the uppermost thread convolution defining said threaded portion, the periphery of said cylindrical section and said thread crest lying in a plane parallel to the axis of said generally cylindrical body thereby providing a smooth transition from threaded portion to cylindrical section, essentially constant in radius of curvature, at the location on the installed implant member, which is surrounded by the juncture between bone and tissue, and

ii. a conical frustum section having its base coterminus with the upper end of said cylindrical section.

2. The dental implant of claim 1 formed of a ceramic composition comprising at least about wt. 7(- aluminum oxide.

3. The dental implant member defined in claim 1 further comprising means formed in said conical frustum section for drivingly connecting said dental implant member with an insert tool.

4. The dental implant defined in claim 3 wherein said last mentioned means comprises a pair of opposed, generally flat, parallel faces.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US3435526 *13 Feb 19671 Apr 1969Heli Coil CorpDevice for securing an artificial tooth to the bone structure of a human jaw
US3466748 *15 Dec 196716 Sep 1969Robert W ChristensenAnchor screw for dental prosthesis
US3579831 *5 Mar 196925 May 1971Stevens Irving JBone implant
US3589011 *10 Jul 196929 Jun 1971Sneer MeerEndosseous pin dental implant method and dental devices used therein
US3787900 *9 Jun 197129 Jan 1974Univ Iowa Res FoundArtificial bone or tooth prosthesis material
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4187611 *7 Oct 197712 Feb 1980University Of Iowa Research FoundationDental retention pin and method
US4199864 *22 Nov 197729 Apr 1980Arthur AshmanEndosseous plastic implant method
US4245359 *16 Mar 197920 Jan 1981Sulzer Brothers LimitedPlug for openings produced by operative procedures in medullated bones
US4331423 *9 Mar 198125 May 1982Yanney Jr James F MMethod and apparatus for connecting an artificial tooth portion to a dentin portion
US4451961 *27 Sep 19825 Jun 1984Bernard WeissmanMethod of making detent device for a removable dental prosthesis
US4746294 *30 Jan 198724 May 1988Domenico ColomboCylindrical threaded pin for dental prosthesis implantations
US4953738 *19 Feb 19884 Sep 1990Stirbis James SOne piece can body with domed bottom
US5071351 *3 Jun 198810 Dec 1991Collagen CorporationDental implant system
US5169309 *10 Dec 19908 Dec 1992Attachments International, Inc.Abutment for dental appliances and the like
US5188800 *10 Oct 199123 Feb 1993Implant Innovations, Inc.Dental implant system
US5254005 *22 Aug 199119 Oct 1993Max ZuestDental implant system and method
US5591029 *5 Aug 19937 Jan 1997Zest Anchors, Inc.Dental implant system
US5645427 *2 Mar 19958 Jul 1997North Shore Dental Porcelains Laboratories, Inc.Dental implant milling tool and methods of the use thereof
US5749732 *3 Oct 199512 May 1998Sendax; VictorDental implantation
US5967783 *19 Oct 199819 Oct 1999Ura; Robert S.Threaded dental implant with a core to thread ratio facilitating immediate loading and method of installation
US6048204 *22 Dec 199811 Apr 2000Lifecore Biomedical, Inc.Self tapping screw type dental implant
US6164969 *21 Mar 199726 Dec 2000Dinkelacker; WolfgangDental implant
US6234797 *12 Oct 199922 May 2001Altiva CorporationDental implant and method for installing the same
US643186710 Aug 200013 Aug 2002Glenn GittelsonDental implant system
US685497211 Jan 200015 Feb 2005Nicholas ElianDental implants and dental implant/prosthetic tooth systems
US734175710 Feb 200511 Mar 2008Nanoproducts CorporationPolymer nanotechnology
US7388042 *28 Apr 200317 Jun 2008Ppg Industries Ohio, Inc.Nanotechnology for biomedical implants
US770897410 May 20054 May 2010Ppg Industries Ohio, Inc.Tungsten comprising nanomaterials and related nanotechnology
US782884816 Apr 20029 Nov 2010Wenzel Spine, Inc.Expandable osteosynthesis cage
US804308925 May 200525 Oct 20113M Innovative Properties CompanyOne piece dental implant and use thereof in prostodontic and orthodontic applications
US805833712 Jun 200715 Nov 2011Ppg Industries Ohio, Inc.Conductive nanocomposite films
US807531230 Aug 200613 Dec 2011Zimmer Dental, Inc.Dental implant with improved osseointegration features
US82313872 Jul 200831 Jul 2012Zimmer, Inc.Porous implant with non-porous threads
US83896039 May 20035 Mar 2013Ppg Industries Ohio, Inc.Thermal nanocomposites
US843529921 Sep 20107 May 2013Wenzel Spine, Inc.Expandable osteosynthesis cage
US854075511 Dec 200624 Sep 2013Robin C. WhitmoreSelf-drilling self-tapping bone screw
US85623462 Jul 200822 Oct 2013Zimmer Dental, Inc.Dental implant for a jaw with reduced bone volume and improved osseointegration features
US85623482 Jul 200822 Oct 2013Zimmer Dental, Inc.Modular implant with secured porous portion
US860278224 Nov 200910 Dec 2013Zimmer Dental, Inc.Porous implant device with improved core
US865186624 Oct 201118 Feb 20143M Innovative Properties CompanyOne piece dental implant and use thereof in prostodontic and orthodontic applications
US879040716 Apr 201329 Jul 2014Liliane AttaliExpandable osteosynthesis cage
US881456730 Aug 200726 Aug 2014Zimmer Dental, Inc.Dental implant prosthetic device with improved osseointegration and esthetic features
US88518918 Dec 20117 Oct 2014Zimmer Dental, Inc.Expandable bone implant
US889998127 Aug 20132 Dec 2014Zimmer Dental, Inc.Dental implant for a jaw with reduced bone volume and improved osseointegration features
US88999822 Jul 20082 Dec 2014Zimmer Dental, Inc.Implant with structure for securing a porous portion
US899262116 Apr 201331 Mar 2015Liliane AttaliExpandable osteosynthesis cage
US906677127 Aug 201330 Jun 2015Zimmer Dental, Inc.Modular implant with secured porous portion
US909539630 Jul 20124 Aug 2015Zimmer Dental, Inc.Porous implant with non-porous threads
US91493452 Jul 20086 Oct 2015Zimmer Dental, Inc.Multiple root implant
US916807723 Jul 201327 Oct 2015Surgical Screw Concepts, LLC.Self-drilling self-tapping bone screw
US93143484 Jun 201519 Apr 2016Wenzel Spine, Inc.Bilaterally expanding intervertebral body fusion device
US943973819 Sep 201313 Sep 2016Zimmer Dental, Inc.Porous implant device with improved core
US9566136 *6 Dec 201014 Feb 2017Rex Implants, LlcEndosseous dental implant
US970705810 Jul 200918 Jul 2017Zimmer Dental, Inc.Patient-specific implants with improved osseointegration
US970709518 Apr 201618 Jul 2017Wenzel Spine, Inc.Bilaterally expanding intervertebral body fusion device
US9730773 *8 May 201515 Aug 2017Maxillent Ltd.Bone graft injection methods
US9730774 *12 May 201515 Aug 2017Maxillent Ltd.Bone graft injection device
US9730775 *12 May 201515 Aug 2017Maxillent Ltd.Bone graft injection device
US97440072 Sep 201429 Aug 2017Zimmer Dental, Inc.Expandable bone implant
US20020116066 *16 Apr 200222 Aug 2002Jean-Luc ChauvinExpandable osteosynthesis cage
US20030207975 *28 Apr 20036 Nov 2003Tapesh YadavNanotechnology for biomedical implants
US20050021036 *21 Jul 200327 Jan 2005Whitmore Robin C.Self-drilling, self-tapping bone screw
US20050065525 *5 Sep 200224 Mar 2005Noble Biocare Ab (Publ)Implant, and tightening member and spacer member for such an implant
US20060127849 *15 Dec 200415 Jun 2006Ricardo LevismanDental implant system
US20060241774 *7 Jun 200626 Oct 2006David AttaliApparatus for providing proper vertebral spacing
US20060269903 *25 May 200530 Nov 2006Bulard Ronald AOne piece dental implant and use thereof in prostodontic and orthodontic applications
US20070162029 *11 Dec 200612 Jul 2007Whitmore Robin CSelf-drilling self-tapping bone screw
US20100003635 *21 Dec 20057 Jan 2010Johan FeithDental implant
US20110009972 *21 Sep 201013 Jan 2011Jean-Luc ChauvinExpandable osteosynthesis cage
US20120251977 *6 Dec 20104 Oct 2012Tomaso VercellottiEndosseous Dental Implant
US20160310192 *8 May 201527 Oct 2016Maxillent Ltd.Bone graft injection methods
US20160310242 *12 May 201527 Oct 2016Maxillent Ltd.Bone graft injection device
US20160310243 *12 May 201527 Oct 2016Maxillent Ltd.Bone graft injection device
USRE37646 *7 Jan 19999 Apr 2002Sulzer Dental Inc.Dental implant system
DE102005005656B4 *8 Feb 20058 Apr 2010Feith, Johan, Dr.Dentalimplantat und Verfahren zum Herstellen eines Dentalimplantats
WO1991010410A1 *11 Jan 199125 Jul 1991Attachments International Inc.Abutment for dental appliances and the like
WO2000023003A1 *19 Oct 199927 Apr 2000Altiva CorporationDental implant and method for installing same
Classifications
U.S. Classification433/174
International ClassificationA61C8/00
Cooperative ClassificationA61C8/0022, A61C8/0075, A61C8/0089
European ClassificationA61C8/00T, A61C8/00G2, A61C8/00F2