Apparatus for rigidly fixing craniomaxillofacial tissue grafts and bone plates

• US 6,398,785 B2
• Filed: 04/13/1999
• Issued: 06/04/2002
• Est. Priority Date: 04/14/1998
• Status: Expired due to Fees

• Current Assignee: Ace Surgical Supply Company Incorporated
• Original Assignee: Ace Surgical Supply Company Incorporated
• Inventors: Balfour, Alan R., Carchidi, Joseph Edward
• Primary Examiner(s): Garbe, Stephen P.
• Assistant Examiner(s): NGO, LIEN M
• Application Number:
  US09/290,433
• Publication Number:
  US 20010004694A1
• Time in Patent Office: 1,148 Days
• Field of Search: 606/73, 606/70-72, 606/74, 606/75, 606/60-62, 411/387, 411/386, 411/384, 411/421, 411/416, 411/418, 411/378, 411/380, 411/411, 411/412, 411/414, 411/424, 411/402, 411/500, 85/41, 85/46, 85/47, 408/213, 408/224
• US Class Current: 606/916
• CPC Class Codes: A61B 17/8615 at the central region of the screw head
• CPC Class Codes: A61B 17/8635 Tips of screws
• CPC Class Codes: A61B 17/888 the driver bit acting on the central region of the screw head
• CPC Class Codes: A61F 2/2846 Support means for bone substitute or for bone graft implants, e.g. membranes or plates for covering bone defects nets or sleeves applied to surface of endoprostheses A61F2/30907; bone plates A61B17/80; bone regeneration in dental surgery A61C8/0006

Abstract

A self-drilling and tapping multi-drive bone screw (10) for rigid fixation of craniomaxillofacial tissue grafts and bone plates has a tip (12a) which incorporates a defined twist drill shaft with a sharp cutting point tip (12b) to easily pierce and drill a pilot hole and prepare for the insertion of self-tapping screw threads (12c). A cylindrical dome shaped head (14) for rigid fixation of craniomaxillofacial tissue grafts and geometrically sized bone plates is formed on the screw distal to the drilling and tapping features. A spline feature (14e) is incorporated into the cylindrically dome shaped head for easy pickup, assembly and insertion of the bone screw with a corresponding spline driver tool (20). The spline driver feature also allows the bone screw (10) to be driven with either a standard square or cross blade driver tool.

Claims

1. Apparatus for retention of tissue grafts and bone plates to a bone site comprising an elongated bone screw body member having a generally cylindrical shaft having a longitudinal axis and a selected diameter and first and second opposite end portions, a sharply pointed, piercing and cutting tip formed at the first end portion aligned with the longitudinal axis, helical drill flutes formed on the shaft along a first axial length of the shaft having an outer diameter generally equal to the selected diameter, the helical drill flutes being separated from one another by generally line contact along the first axial length, self-tapping bone screw threads formed on the shaft along a second axial length of the shaft, the bone screw threads having an inner diameter generally equal to the selected diameter and being contiguous with the first axial length, the self-tapping bone screw threads having a second outer diameter greater than the selected diameter, the helical drill flutes aligned with and forming a continuation of the self-tapping bone screw threads along a first portion of the second axial length forming cutting flutes and a driving head formed at the second end portion of the shaft, the driving head extending radially outwardly beyond the shaft forming an outer most periphery and being formed with a frusto-conical surface extending from the outer most periphery to the shaft, the diameter of the frusto-conical surface increasing in a direction going from the first end portion to the second end portion, and a female driving spline formed at the second end portion of the member aligned with the longitudinal axis of the body member, the female driving spline comprises a polygonal central recess and a radially extending slot communicating with the central recess, and a circular bore extending along the longitudinal axis, the circular bore being in communication with, and extending beyond, the central recess.

2. A driving tool for use with a threaded member having a longitudinal axis and having a female driving spline formed at an end thereof having a central recess having polygonal sides of a selected number, the sides each being generally flat and lying in a plane extending parallel to the longitudinal axis, a radially extending slot communicating with the central recess and intersecting at least one of the sides and a cylindrical bore in communication with, and extending beyond, the central recess, comprising an elongated body member having a longitudinal axis, the member having a polygonally shaped end portion having the selected number of sides, the sides each being generally flat and lying in a plane extending parallel to the longitudinal axis of the elongated member and having a size chosen to closely fit within the polygonal sides of the central recess, a blade portion extending outwardly from the polygonally shaped end portion having a configuration chosen to be closely received in the at least one radially extending slot and a generally cylindrical male holding portion extending along the longitudinal axis of the elongated member beyond the polygonal shaped portion, the generally cylindrical male holding portion formed with a friction locking taper to closely fit within the cylindrical bore of the spline.

3. Apparatus for retention of tissue grafts and bone plates to a bone site comprising an elongated body member having a generally cylindrical shaft first and second opposite end portions, a sharply pointed, piercing and cutting tip formed at the first end portion aligned with the longitudinal axis, helical drill fluted formed on the shaft along a first axial length of the shaft having an outer diameter generally equal to the selected diameter, self-tapping bone screw threads formed on the shaft along a second axial length of the shaft, the bone screw threads having an inner diameter generally equal to the selected diameter, the helical drill flutes aligned with and forming a continuation of the self-tapping bone screw threads along a first portion of the second axial length forming cutting flutes and a driving head formed at the second end portion of the shaft, the driving head extending radially outwardly beyond the shaft forming an outer periphery and being formed with a frusto-conical surface extending from the outer periphery to the shaft and a female driving spline formed at the second end portion of the member aligned with the longitudinal axis of the body member, the female driving spline having side surfaces forming a polygonally shaped recess, the side surfaces each being generally flat and lying in a plane which is parallel to the longitudinal axis of the body member, at least one radially extending blade shaped slot communicating with the recess, a cylindrical bore extending along the longitudinal axis of the body member in communication with and extending beyond the polygonally shaped recess, an elongated tool member having a longitudinal axis and having a polygonally shaped portion having the selected number of sides, the sides each being generally flat and lying in a plane extending parallel to the longitudinal axis of the tool member and having a size chosen to closely fit within the polygonally shaped recess, a blade portion extending from the polygonally shaped portion having a configuration chosen to be closely received in the at least one radially extending slot and a generally cylindrical male holding portion extending along the longitudinal axis of the elongated member beyond the polygonally shaped portion, the generally cylindrical male holding portion formed with a friction locking taper configured to closely fit within the cylindrical bore of the spline.