A u ~ l r a l i a nI k n t a l Iotirn~il.February. 1977

46 Volume 22, No. I

Post core systems in crown and bridgework* P. J. Henry AND

R. C. Bower A8sTKAc~-Ptl~p~eSSteeth require reinforcement if they are t o act as supports for crown and bridgework restorations. Post core reinforcements can be nccomplishcd by utilization of post core systems which offer the clinician a broad range of techniques. T h e mechanical procedures involved should be biologically oriented and related to stress distribution to the tooth root. (Heceir,ed for prihliciitioti Jrrly. 1976)

Introduction Most entlodontically treated teeth requirc restoration t o prepared forni before they can be used ;is supports in crown and bridge prosthodontics!. Prepared f o r m can be achieved with a post core utilising the root system for its retention. Post support is also indicated electively in teeth o f narrow cervical diameter, malformed teeth, and nialnligned teeth that require coronal repositioning lo achieve adequate aesthetics and function. Clinically the time proven accepted method of constructing ii post core has been with cast gold, fabricated directly o r indirectly froni a prepared root canal. generally tapered to permit ready withdrawal. More recently preformed wrought alloy post systems of precious alloy2.3 and steel"." have been developctl in a n effort to provide greater precision antl strength. Concomitantly other methods have been advocated based o n economic factors of reduced choirtime m c l inexpensive materials and armanien-

*

Lecture presenird i i i the 21st Australian Dental Congress, Adelaide. February, 1976.

I h r a b a n , 13. J.-The rcstoriilion of pulpless teeth. 13. C l i n . Nth A m . , 11:4. 632-653 ( N o v . ) 1967. Gerstein. H.. and Burnell. S. C.-Prefabricared precision dowels. J . A . D . A . . 68:6. 787-791 ( J u n e ) 1964. :: Hiiraban 13. J.-A simplified method for making posts and ;ores. J . Pros. Dent.. 24:3. 287-297 (Sept.) 1970. 4 K u r e r , P . F.-Uetcntion o f post crowns. A solution of the problem. Brit. D. J., 123:3, 167-169 (Aug. 1 5 )

tarium. Such methods employ brass dowel pins". bur shanks, acrylics. composites". wires and amalgam. These met hods cannot be compared to metal post cores in ternis of strength o r tltrrnbility and will not be considered further. Also, materials such :IS brass d o not conform t o the biologic s t and a r k req ti i red of dent a I rest o r ii t i ve mat er in1s . T h e purpose o f this paper is t o compare tind contrast the various systems ;tvnilnble. and to review the basic principles involved in the restoration of the root filled tooth to nornial function. Part I - anterior teeth All root filled anterior teeth require reinforcement by ii post antl core, Before :I tooth is selected for treatment it must be assessed ;IS having ;I positive strategic value. Such assessment is based o n the combined entlotlontic and periodontic states. together with ;in evaluation of the functional analysis o f the case. Functional analysis includes both ii consideration of functional stress and parafunctional loading. For example. high strcss situations such its long span bridges subjected l o n~itt1r;il tooth bruxism forces. require greater support than it short span mandibular bridge opposed to it f u l l tipper denture.

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1967.

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Scully. 8. I

Post core systems in crown and bridgework.

A u ~ l r a l i a nI k n t a l Iotirn~il.February. 1977 46 Volume 22, No. I Post core systems in crown and bridgework* P. J. Henry AND R. C. Bower...
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