PERMANENTLY IMPLANTABLE FIXTURE

United States Patent H9i

Bostrom

[in 3,732,621 [45] May 15, 1973

[54] PERMANENTLY IMPLANTABLE FIXTURE MEANS FOR PROTHESIS AND THE LIKE

[75] Inventor: Bertil I. Bostrom, Taby, Sweden

[73] Assignee: AGA Aktiebolag, Ligingo near Stockholm, Sweden

[22] Filed: Mar. 12, 1971

[21] Appl. No.: 123,707

[30] Foreign Application Priority Data

Mar. 25, 1970 Sweden 4210/70

[52] U.S. CI 32/10 A

[51] Int. CI A61c 13/00

[58] Field of Search 32/10 A, 10, 11,

32/12, 13

[56] References Cited

UNITED STATES PATENTS 3,618,212 11/1969 Weissman 32/10 A

Primary Examiner—Robert Peshock
Attorney— Larson, Taylor & Hinds

[57] ABSTRACT

As a permanently implantable fixture means for prosthesis and the like in a human body, especially for implanting a dental prosthetic structure, a means composed by at least two parts has been proposed for attaching the prosthetic structure to bone tissue. A first part of the attachment unit is intended to be applied in such a way in the bone tissue that it will remain embedded in said tissue during all of the time required

for healing the damage which occurs when the first part is attached to the bone and while the bone tissue grows into the attachment, and a second part of the attachment unit, serving as mounting unit for the prosthetic structure and so shaped that it may be attached to the first part of the attachment unit and pass through such weak tissue covering the bone tissue. The mounting unit is intended to combine the attachment unit inserted into the bone tissue with a prosthetic structure located outside of the weak tissue.

Such permanently implantable attachment means have been used for permanently attaching dental prosthetic structure to the jawbone in human bodies. The jawbones rather often have a narrow cross-section, and the longitudinal direction of the cross-section may be diverge sharply at different parts of the same jaw and/or the same jawbone but especially between the upper jaw and the lower jaw. This, among other reasons, results in so-called over-bite or under-bite, respectively. As the attachment units must, for technical reasons, be well centered in the jawbone, the longitudinal directions of the attachment units will not always be in alignment mutually in the same jaw, nor between the upper jaw and the lower jaw. This is a serious disadvantage, because the longitudinal direction of the teeth in the prosthetic structure should be in alignment with the longitudinal direction of the attachment unit. A compromise between these demands either a weak or completely unsatisfactory attachment in the jawbone or non-aligned prosthetic structure. Therefore, there is a need for an attachment means of the kind indicated above, in which the said first part attached to the jawbone may form an angle with the said second part to which the prosthetic structure is attached.

20 Claims, 7 Drawing Figures