Self-drilling self-tapping bone screw
View Patent ↗A self-drilling, self-tapping bone screw includes a body having a head at one end and a cutting end at an opposite end, the cutting end having a generally flat cutting surface supporting two symmetrical cutting edges which extend from the longitudinal centerline to diametrically opposed thread start points. A recess is formed in the head for receiving an end of an insertion tool. A dual lead thread extends outwardly from the body in a spiral path from the cutting end towards the head. The dual lead thread pitch is tapered towards the cutting end, and transitions to a straight or slightly tapered thread towards the head.
1. A self-drilling bone screw comprising:
a body having:
(a) a longitudinal centerline;
(b) a head at a first end; and
(c) a cutting end at a second end, the cutting end including a flat rectangular cutting surface oriented perpendicularly to the longitudinal centerline and having:
(i) a first cutting edge which extends perpendicular from the longitudinal centerline to a first thread start point; and
(iii) a second cutting edge which extends perpendicular from the longitudinal centerline to a second thread start point, the second cutting edge being parallel to the first cutting edge; and
a dual lead thread extending outwardly from the body in a spiral path from the cutting end towards the head.
2. The bone screw of claim 1 , wherein said dual lead thread is multi-pitched.
3. The bone screw of claim 2 , wherein said dual lead thread is tapered towards the cutting end and transitions to a straight or slightly tapered thread towards the head.
4. The bone screw of claim 1 , including a recess formed in the head configured to receive an end of an insertion tool.
5. The bone screw of claim 1 , wherein said bone screw is comprised of a medical grade titanium alloy.
6. The bone screw of claim 1 , wherein said bone screw is approximately 1.0 to 2.0 mm in diameter and approximately 3.0 to 6.0 mm in length.
7. The bone screw of claim 1 , wherein the flat rectangular cutting surface is approximately 0.5 mm in length and 0.1 mm in width.
8. A self-drilling bone screw, comprising:
a body having:
(a) a longitudinal centerline;
(b) a head at a first end; and
(c) cutting edge including a flat rectangular cutting surface at a second end, the flat rectangular cutting surface oriented perpendicularly to the longitudinal centerline and having:
(i) a first cutting edge which extends perpendicular from the longitudinal centerline to a first thread start point; and
(iii) a second cutting edge which extends perpendicular from the longitudinal centerline to a second thread start point, the second cutting edge being parallel to the first cutting edge; and
a dual lead thread extending outwardly from the body in a spiral path from the cutting end towards the head, the dual lead thread being multi-pitched such that the pitch of the thread:
(a) is tapered towards the cutting end; and
(b) transitions to a straight or slightly tapered thread towards the head.
9. The bone screw of claim 8 , including a recess formed in the head configured to receive an end of an insertion tool.
10. The bone screw of claim 8 , wherein said bone screw is comprised of a medical grade titanium alloy.
11. The bone screw of claim 8 , wherein said bone screw is approximately 1.0 to 2.0 mm in diameter and approximately 3.0 to 6.0 mm in length.
12. The bone screw of claim 8 , wherein the flat rectangular cutting surface is approximately 0.5 mm in length and 0.1 mm in width.
13. A self-drilling, self-tapping bone screw, comprising:
a body comprised of medical grade titanium alloy of approximately 1.0 to 2.0 mm in diameter and approximately 3.0 to 6.0 mm in length, the body having:
(a) a longitudinal centerline;
(b) a head at a first end; and
(c) a cutting end comprising a flat rectangular cutting surface at a second end oriented perpendicularly to the longitudinal centerline and having:
(i) a first cutting edge which extends perpendicular from the longitudinal centerline to a first thread start point; and
(iii) a second cutting edge which extends perpendicular from the longitudinal centerline to a second thread start point, the second cutting edge being parallel to the first cutting edge;
a dual lead thread extending outwardly from the body in a spiral path from the cutting end towards the head, the dual lead thread being multi-pitched such that the pitch of the thread is:
(a) tapered towards the cutting end; and
(b) transitions to a straight to slightly tapered thread towards the head; and
a recess formed in the head configured to receive an end of an insertion tool.
14. The bone screw of claim 13 , wherein the flat rectangular cutting surface is approximately 0.5 mm in length and 0.1 mm in width.