التفاصيل البيبلوغرافية
| العنوان: |
Precision cast dental instrument |
| Document Number: |
20070184406 |
| تاريخ النشر: |
August 9, 2007 |
| Appl. No: |
11/726905 |
| Application Filed: |
March 23, 2007 |
| مستخلص: |
An endodontic file (200) is provided particularly adapted for the removal of tooth structure, decayed or damaged nerve tissues or dentine material on the interior walls of a root canal or dentine and/or enamel from the external tooth wall. The endodontic instrument includes a shaft (202) having a shank portion (204) and a generally elongated working portion (206). The working portion preferably includes cutting or abrading features (232) adapted upon rotation and/or reciprocation of the instrument to cut, abrade or remove tissue from the interior walls of a root canal or dentine and/or enamel from the external tooth wall. The working portion extends from a proximal end (207) adjacent the shank portion to a distal end (208) terminating at a tip (250). The entire instrument and/or at least the working portion thereof is formed of an amorphous or essentially amorphous material having no or essentially no detectable crystalline structure and/or from a nanocrystalline material having an average crystalline grain size less than about 1 μm. The instrument may be formed by conventional grinding operations or by direct casting, forging or molding, in a manner producing an integral as-molded instrument having one or more sharp cutting edges. The instrument is inexpensive to manufacture and exhibits improved cutting-edge sharpness, wear resistance, lubriciousness and resistance to breakage. |
| Inventors: |
Mason, Robert M. (Tallahassee, FL, US) |
| Claim: |
1.-27. (canceled) |
| Claim: |
28. A method of manufacturing a dental instrument adapted for the shaping and/or removal of tooth structure, said instrument comprising a shaft having a shank portion and a working portion, said working portion having one or more sharp cutting features thereon adapted for the removal of said tooth structure upon rotation and/or reciprocation of the instrument, said method comprising forming the dental instrument by pouring or injecting a metal alloy in a molten or liquid state into a die or mold with a desired instrument shape including said cutting features and then cooling the metal alloy to form an integral as-molded instrument having said one or more sharp cutting features. |
| Claim: |
29.-32. (canceled) |
| Claim: |
33. The method of claim 35 wherein said glassy metal alloy comprises one or more of the following elements: zirconium, beryllium, titanium, copper, or nickel. |
| Claim: |
34. The method of claim 35 wherein said glassy metal alloy comprises one of the following base alloy systems: Zr—Ti, Ni—Ti, Cu—Ti—Zr, Ln—Al—TM, Mg—Ln—TM, Zr—Al—TM, Hf—Al—TM, Ti—Zr—TM, Zr—Al—Co—Ni—Cu, Zr—Ti—Al—Ni—Cu, Zr—Ti—Nb—Al—Ni—Cu, and/or Zr—Ti—Hf—Al—Co—Ni—Cu, where Ln is a lanthanide metal, and TM is a transition metal of the Groups VI to VIII. |
| Claim: |
35. The method of claim 28 wherein said cooling step comprises rapidly cooling said alloy from its molten state to a solid state in such a manner that a glassy metal alloy substantially without an ordered crystalline structure is formed. |
| Claim: |
36. (canceled) |
| Claim: |
37. The method of claim 35 wherein said rapid cooling step is performed at a rate greater than about 10° C. per second to form the desired instrument shape. |
| Claim: |
38. The method of claim 28, further comprising a machining step to refine the one or more sharp cutting features. |
| Current U.S. Class: |
433102/000 |
| Current International Class: |
61 |
| رقم الانضمام: |
edspap.20070184406 |
| قاعدة البيانات: |
USPTO Patent Applications |