Upload
andrew-tung-nguyen
View
226
Download
1
Embed Size (px)
Citation preview
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 1/45
Fabrication of a cast post and
core by direct technique
Parul Agarwal, B.D.S., M.S.
Michael Linebaugh, D.D.S., M.S.Scott Joslin, R.D.H.
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 2/45
Cast Post and Core
The cast post and core is utilized in situations when inadequate coronal tooth structureremains to support a crown. The cast post and
core utilizes the retention available in the canalspace remaining post endodontic treatment. Asthe retention of the CPC is achieved through
cement contact to internal canal surface area, itis still necessary to have adequate ferrule of3mm to support the crown.
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 3/45
Armamentarium
Crown and Bridge cassette
Including GC Pattern Resin
Endo cassette Including Gates Glidden setup
High and Low speed handpieces
Parapost™ Kit Torch
NaOCl and Syringe
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 4/45
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 5/45
Cast post and core
Canal Preparation
The tooth was prepared for a crown, note that all of the unsupported tooth
structure and coronal undercuts were removed.
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 6/45
Cast post and core:
Canal Preparation
A pre-operative radiograph isneeded to determine thelength of the canal
Remember that it isimperative to allow 4-5mmof remaining Gutta Perchaapically
Also look for canal
curvatures as they will not beable to be negotiated in thepost preparation
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 7/45
Cast post and core:
Canal preparation
Once the length of postpreparation is determined,canal preparation is needed
Several methods exist forpreparation
Warm Instrument Searing
Peeso Reamers
Gates Glidden
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 8/45
Cast Post and Core
Canal Preparation Warm Instrument Searing
Mark desired depth with andendodontic stopper
An endodontic plugger is heateduntil it is glowing red
The plugger is inserted into thecanal with apical pressure
When resistance is achieved theplugger should be rotated fromside to side, to prevent pulling out
all of the remaining gutta percha,and removed
This should be performed untilineffective and followed withrotary instrumentation
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 9/45
Cast post and core:
Canal preparation Gates – Glidden drill Mark depth with endo
stopper Place a drop of NaOCl
in the canal forlubrication Begin preparation with
bur spinning prior tocanal entry
DO NOT FORCE THE BUR, yield toresistance andreevaluate
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 10/45
Cast post and core:
Canal preparation
Gates Gliddentaken to length
Remember the
minimum widthacceptable is ayellow post whichcorresponds to a
#4 Gates Glidden
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 11/45
Cast post and core:
Canal Preparation
Post preparation after removal of Gates Glidden
Flush with NaOCl, take care if no isolation is in placeas NaOCl is caustic
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 12/45
Cast post and core:
Resin pattern fabrication Following space preparation,
Fabrication of the resin patternoccurs
A SERRATED plastic post ormetal post can be used.
When a plastic post is used, thepattern completely burns out, andthe post is formed entirely in thecasting alloy.
When a metal post is used, moltenalloy is cast around the post,
which mechanically interlocks withpreviously developed notches toproduce a rigid structure.
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 13/45
Cast post and core:
Resin pattern fabrication
The metal post is notched occlusally so that goodinterlocking with the core material can be achieved.
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 14/45
Cast post and core:
Resin pattern fabrication
In this post and core fabrication a plastic post
has been used. Note that the posts in both instances are the
SERRATED variety, do not use the smooth
posts
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 15/45
Cast post and core:
Resin pattern fabrication
Plastic post
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 16/45
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 17/45
Cast post and core:
Resin pattern fabrication
When adding theGC Resin to theplastic or metal
post, a salt andpepper technique isutilized
For finer additions,the brush can becut to a point withsharp scissors
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 18/45
Cast post and core:
Resin pattern fabrication
Cutting the brush to a point
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 19/45
Cast post and core
Resin pattern fabrication
Note the finer tip on the cut brush on the right
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 20/45
Cast post and core
Resin pattern fabrication
Trying in the plastic post
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 21/45
Cast post and core
Resin pattern fabrication
Once the post is in place, grab it at the coronal most extent of the preparation with the cotton pliers, remove it and re-measure to confirm the post is fullyseated
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 22/45
Cast post and core
Resin pattern fabrication
The preparation is cleaned and dried with air and paper points
It is then lightly lubricated with petroleum jelly to prevent adhesion
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 23/45
Cast post and core:
Resin pattern fabrication
GC Pattern Resin application using the “Salt and Pepper”
Technique
C t p t nd r
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 24/45
Cast post and core:
Resin pattern fabrication
Resin is added by the “Salt and Pepper” technique, dipping asmall brush in a monomer and then into polymer and applying itto the post. Before it fully hardens, it is loosened and reseated
several times. This is why it is important to leave the remainingcoronal extent of the post.
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 25/45
Cast post and core
The core is slightly overbuild and is let to polymerize fully. Theshape of the pattern should resemble an ideal preparation andshould be completely sealed at the apical margins.
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 26/45
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 27/45
Cast post and core:
Resin pattern fabrication
The resin pattern is removed and the excess plasticsprue is cut off
Replace the Pattern to confirm all margins are closed
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 28/45
Cast post and core:
Resin pattern fabrication
Resin pattern is then sent to the laboratory for sprueing andcasting in the desired alloy.
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 29/45
Laboratory Wait Time
As the Cast post and Core is a Laboratorydependent procedure, a wait time is necessary while the lab fabricates the alloy core from the
pattern
Be sure to ask your lab how long they want forfabrication time.
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 30/45
Cast post and core:
Finishing of the post and core
Cast Post and Core returned from the lab
Be sure to check for flashing and bubbles in the finished product
as these may inhibit the CPC from fully seating
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 31/45
Cast post and core:
Finishing of the post and core
Try in the CPC
Check for Draw
There should be no adhesions with insertion
Marginal Fit
Adjust as necessary until desired fit is achieved
It is important that you make a mental note of the fitso that when you are cementing the CPC you have areference to be sure it is adequately and completelyseated
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 32/45
Cast post and core:
Cementation of the post and core
Lentulospiral rotary pastefillers are used to fill the postspace completely.
It is important to fill all thedead space within the rootcanal system.
Voids may be a cause ofperiodontal inflammation viathe lateral canals.
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 33/45
Cast post and core:
Cementation of the post and core
Required components for cementation
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 34/45
Cast post and core:
Cementation of the post and core
Choose the cement to be used for seating the CPC
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 35/45
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 36/45
Cast Post Core Cementation
After assembling all of the cementationcomponents, be sure to isolate the tooth andprepare/dry the canal as prescribed depending
upon the type of cement you are using
Be sure all of the temporary cement is removedfrom the canal and preparation as it may inhibit
seating of the CPC or setting of the cement
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 37/45
Cast post and core:
Cementation of the post and core
The canal is dried with a paper point prior to cementation.
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 38/45
Cast post and core:
Cementation of the post and core
Placement of the cement on the Lentulospiral
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 39/45
Cast post and core:
Cementation of the post and core
Place the CPC in the post space and apply apical pressure
Clear the excess cement from the margin and check to make sureit is completely seated
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 40/45
Cast post and core:
Clearing cement from the margin after cement setting
Be sure not to disturb the post when the cement is setting as this
may weaken the cement bond
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 41/45
Cast post and core:
Finished CPC
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 42/45
Cast post and core:
Often, minor preparation may be needed after seating the CPC
BE SURE the cement is completely set before doing this
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 43/45
Cast post and core:
Final restoration
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 44/45
Cast post and core:
Cementation of the final restoration
8/12/2019 Cast Post & Core
http://slidepdf.com/reader/full/cast-post-core 45/45
References
Trope M, Maltz DO, Tronstad L Endod Dent TraumatoGoodacre CJ,Spoolnik KJ
Goodacre CJ, Spoolnik KJ J Prosthodont 1995;4:51 l. 1985 Jun;1(3):108-11
Standlee JP, Caputo AA et al J Prosthet Dent 1980;44:398-404 Barkhordar RA, Radke R, Abbasi J J Prosthet Dent. 1989
Jun;61(6):676-8.
Gargiulo et al J Periodontol 1961;32:261
Sorensen JA, Engelman MJ. J Prosthet Dent. 1990 May;63(5):529-36.
Reinhardt RA et al J Dent Res 1983;63:1002-1008
Morgano SM J Prosthet Dent 1996;75:375-80