Root canal filling device including releasably reusable inserter tool

Abstract

A root canal filler assembly including a single use obturator and a multiple use elongate inserter tool is disclosed. The oburator includes a metallic core and a plasticizable coating, preferably formed of gutta percha. One end of the metallic core extends beyond the plasticizable coating to support a connector assembly. The multiple use inserter tool is removably connectable to the oburator to insert, remove, adjust, and reposition the obturator in a root canal. The inserter tool includes at one end a connector assembly which engages the obturator and at the other end a handle to facilitate manipulation of the assembly by the dentist. The elongate inserter tool may be reused as required, both to remove or reposition a previously inserted obturator and to insert additional obturators in other root canals. A method of filling and sealing a root canal employing the disclosed root canal filler assembly is also provided.

I claim: 
     
       1. A root canal filter assembly for inserting a biocompatible filler material into the canal of the root of a tooth to fill and seal the canal following removal of the tooth pulp and treatment of the canal, said filler assembly comprising: (a) single use filler means conforming substantially to the configuration of the root canal to fill and seal the root canal from the apex of the root to a desired distance away from the apex, said single use filler means having an apical end, and an insertion end, wherein said insertion end includes a threaded filler connector assembly, and   (b) multiple use inserter means for inserting said filler means into the root canal and properly positioning said filler means in the root canal, said multiple use inserter means having a connector end and a handle end wherein said connector end includes a threaded inserter connector assembly configured to threadedly and removably engage the threaded filler connector assembly of said filler means.   
     
     
       2. The root canal filler assembly of claim 1, wherein said filler means includes a relatively rigid longitudinal core portion and a relatively flexible plasticizable coating portion extending axially along said core portion from said apical end to terminate short of said insertion end to leave said core portion exposed al the insertion end of said filler means. 
     
     
       3. The root canal filler assembly of claim 2, wherein said filler connector assembly is positioned on said exposed core portion. 
     
     
       4. The root canal filler assembly of claim 3, wherein said inserter connector assembly is positioned interiorly of the connector end of said insertion means. 
     
     
       5. The root canal filler assembly of claim 4, wherein said inserter connector assembly and said filler connector assembly comprise correspondingly threaded sections of said inserter means and said filler means is threadedly engaged by said inserter means. 
     
     
       6. The root canal filler assembly of claim 5, wherein said filler means core portion is formed of metal. 
     
     
       7. The root canal filler assembly of claim 6, wherein said filler means coating portion is formed of gutta percha. 
     
     
       8. The root canal filler assembly of claim 5, wherein said filler means coating portion comprises two layers of differentially melting plasticizable material, said innermost layer having a higher melting point than said outermost layer. 
     
     
       9. The root canal filler assembly of claim 8, wherein the innermost of said two layers comprises high melting gutta percha and the outmost of said two layers comprises low melting gutta percha. 
     
     
       10. The root canal filler assembly of claim 1, wherein said inserter means further includes handle means located at the handle end thereof to facilitate the insertion and manipulation of said inserter means in a root canal. 
     
     
       11. The root canal filler assembly of claim 10, wherein said inserter means further includes measuring means for measuring the distance said filler assembly has been inserted into said root canal and assessing proper placement of the filler assembly in the root canal. 
     
     
       12. The root canal filler assembly of claim 11, wherein said measuring means comprises a stop axially slidable along said inserter means. 
     
     
       13. A filling device for refilling a tooth root canal with a canal filling during treatment of the tooth to permit the canal filling to be easily inserted, positioned, and removed, said filling device comprising: an elongate filler cone having first and second ends and comprising a relatively narrow tip portion formed at said first end, said elongate filler cone being insertable and adjustable within and removable from the tooth root canal;   removable elongate insertion means for inserting, adjusting, repositioning, and removing said elongate filler cone in the root canal, said removable elongate insertion means comprising first and second ends and a handle portion formed at said first end, and said removable elongate insertion means being reusable: and   connection means disposed at said second end of said removable elongate insertion means for releasably connecting said removable elongate insertion means to said second end of said elongate filler cone such that said elongate filler cone can be connected to, removed from, and reconnected said removable elongate insertion means as required.   
     
     
       14. A root canal filling device according to claim 13 wherein said elongate filler cone is formed with external threads on said second end and wherein said connection means comprises a hollows internally threaded portion formed at said second end of said removable elongate insertion means, said elongate filler cone and said removable elongate insertion means being releasably, threadably connectable and reconnectable together. 
     
     
       15. A root canal filling device according to claim 14 wherein said second end of said elongate filler cone comprises a relatively narrow tip portion receivable in said hollow internally threaded portion to facilitate connecting said elongate filler cone to said removable elongate insertion means. 
     
     
       16. A root canal filling device according to claim 13 wherein said relatively narrow tip portion formed at said first end of said elongate filler cone is sufficiently rigid to resist binding or bending back when said elongate filler cone is inserted into a root canal. 
     
     
       17. A root canal filling device according to claim 13 wherein said removable elongate insertion means comprises a rigid inserter shaft. 
     
     
       18. A root canal filling device according to claim 17 wherein said inserter shaft is formed of metal. 
     
     
       19. A root canal filling device according to claim 17 wherein said inserter shaft is formed of plastic. 
     
     
       20. A root canal filling device according to claim 17 further comprising measuring means for indicating the approximate length of the root canal to thereby reduce the incidence of long or short placement of said elongate filler cone within the root canal. 
     
     
       21. A root canal filling device according to claim 20 wherein said measuring means comprise a rubber disk slidably mounted on said inserter shaft near said first end below said handle. 
     
     
       22. A root canal filling device according to claim 13 wherein said handle is shaped like a root canal file. 
     
     
       23. A root canal filling device according to claim 13 wherein said handle is formed of plastic. 
     
     
       24. A root canal filling device according to claim 13 wherein said handle is formed of rubber. 
     
     
       25. A root canal filling device according to claim 13 wherein said elongate filler cone comprises an inner core layer and an outer shell layer. 
     
     
       26. A root canal filling device according to claim 25 wherein said inner core layer is formed of metal. 
     
     
       27. A root canal filling device according to claim 26 wherein said inner core layer is formed of manlure. 
     
     
       28. A root canal filling device according to claim wherein said outer shell layer is formed of a thermoplastic material. 
     
     
       29. A root canal filling device according to claim 28 wherein said outer shell layer is formed of gutta percha. 
     
     
       30. A root canal filling device according to claim 25 wherein said elongate filler cone further includes a retentive surface formed on said inner core layer. 
     
     
       31. A method of filling the root canal of a tooth with a biocompatible filler after the tooth has been opened to expose the root canal and the canal has been cleared of diseased or damaged pulp comprising the steps of: (a) selecting an appropriately sized obturator means including an elongated rigid core portion, a flexible plasticizable coating portion covering said core portion to extend from one end of said core portion axially along said core portion, and a threaded connector assembly at the other end of said core portion for filling and sealing the apical end of the root canal:   (b) temporarily connecting the threaded connector assembly of said obturator means to a correspondingly threaded connector assembly on the connector end of an inserter means for inserting said obturator means into the root canal by screwing said connector assemblies together to form a tool canal filler assembly: (c) inserting said root canal filler assembly into the cleared root canal so that the coating portion of the obturator means is positioned within the canal to fill and seal the apical end of the root canal:   (d) disconnecting the inserter means from the obturator means by unscrewing the inserter means threaded connector assembly from the obturator means threaded connector assembly; (e) removing said inserter means from the root canal to leave the obturator means in the root canal, thereby permitting said inserter means to be reused: and   (f) sealing the portion of the root canal not filled by the obturator means and restoring the integrity of the tooth.   
     
     
       32. The method of filling a root canal described in claim 31, further including the steps of removing the seal formed in step (f), reinserting said inserter means into said root canal, screwing said threaded connector assembly of said obturator means into said threaded connector assembly of said inserter means, repositioning said obturator means, disconnecting said threaded connector assemblies, and removing said inserter means from said root canal. 
     
     
       33. The method of filling a root canal described in claim 31, further including the step of, after step (c) but before step (d), heating said obturator means to plasticize said plasticizable coating. 
     
     
       34. The method of filling a root canal described in claim 31, further including the step of, after step (e). inserting a support post into said root canal to extend from said obturator means to the tooth surface. 
     
     
       35. The method of filling a root canal described in claim 31, further including the step of, after step (c) but before step (d). using measuring means to measure the distance said assembly extends to said root canal. .Iadd. 
     
     
       36.  A biocompatible filler for insertion into the canal of the root of a tooth to fill and seal the canal following removal of tooth pulp and treatment of the canal, said filler comprising: a relatively rigid longitudinal core; and   a relatively flexible plasticizable coating extending axially along at least a portion of said core, said plasticizable coating comprising an innermost layer and an outermost layer of differentially melting plasticizable material. .Iaddend. .Iadd.37. The filler of claim 36, wherein the innermost layer has a higher melting point than the outermost layer..Iaddend. .Iadd.38. The filler of claim 36, wherein the innermost layer comprises high melting gutta perch and the outermost layer comprises low melting gutta percha. .Iaddend. .Iadd.39. The filler of claim 36, wherein the core is metal..Iaddend. .Iadd.40. The filler of claim 39, further comprising a coating of metal plasma on the metal core underneath   
     
     
        the innermost layer of gutta percha..Iaddend. .Iadd.41.  A relatively flexible, plasticizable biocompatible filler for insertion into the canal of a root of a tooth to fill and seal the canal following removal of tooth pulp and treatment of the canal, said filler comprising: a first plasticizable material which is essentially solid at room temperature and which is spreadable in the canal under heat and/or mechanical action so as to flow therein;   a second plasticizable material which is essentially solid at room temperature and which is spreadable in the canal under heat and/or mechanical action so as to flow therein under substantially different conditions of heat and/or mechanical action as compared to said first plasticizable material, wherein said first and second plasticizable materials spread in the canal to fill the canal during a filling   
     
     
        procedure, one spreading prior to the other..Iaddend. .Iadd.42.  The material of claim 41, wherein said first plasticizable material and said second plasticizable material have substantially different melting points..Iaddend. .Iadd.43. The filler of claim 41, wherein said first plasticizable material comprises a relatively high melting point gutta percha and said second plasticizable material comprises a relatively low melting point gutta percha..Iaddend. .Iadd.44. The filler of claim 41, wherein said first plasticizable material comprises an inner layer of relatively high melting point gutta percha and said second plasticizable material comprises an outer layer of relatively low melting point gutta percha surrounding the layer of relatively high melting point gutta percha..Iaddend.