indirect restorations haris
DESCRIPTION
Preparation for an Indirect restoration in DentistryTRANSCRIPT
Haris MehmoodFinal year BDS
LEARNING OBJECTIVESLEARNING OBJECTIVES
Identify the types of materials that can be used when placing indirect composite resin restorations.
Discuss the clinical considerations for placing indirect restorations.
Describe the preparation, adhesion, and cementation processes for placing indirect restorations.
INDIRECT INDIRECT RESTORATIONRESTORATIONIt is a technique of fabricating the restoration
outside of the mouth using the impression of the prepared tooth.
Types Of Indirect Types Of Indirect RestorationsRestorationsInlays and OnlaysCrownsBridgesVeneers
INLAYSINLAYSDefinition:
An inlay is an indirect restoration (filling) consisting of a solid substance (as gold or porcelain) fitted into a cavity in a tooth between cusps and cemented into place.
INLAYSINLAYS
ONLAYS ONLAYS Definition:
A cast type of restoration that is retained by frictional and mechanical factors in the preparation of the tooth and restores one or more cusps and adjoining occlusal surfaces of the tooth.
ONLAYS ONLAYS
MATERIALS AVAILABLEMATERIALS AVAILABLEComposite
Hybrid resin compositeMicrofilled resin compositeCeromer or Ceramic optimized polymer
A Newer generation of resin material
CeramicsPorcelain inlays and onlaysCAD/CAM ceramic Restorations
PREPARATION FOR PREPARATION FOR INDIRECT RESTORATIONSINDIRECT RESTORATIONSPreparation is almost same for all types of
materials including ceramics, resin composite inlays and onlays and CAD/CAM inlays and onlays.
PREPARATION DESIGNPREPARATION DESIGNDivergent, relatively non retentiveRounded proximal boxesGrooves should not be usedPrimary resistance and retention form by
adhesion to enamel and dentin.Walls and floor of preparation smooth and
evenInternal line angles rounded
PREPARATION DESIGNPREPARATION DESIGN
IDEAL DIAMOND FOR THE IDEAL DIAMOND FOR THE PREPARATION OF PREPARATION OF INDIRECT INLAYS AND INDIRECT INLAYS AND ONLAYSONLAYS
This kindof diamond will provide the proper degree of divergence,a butt-joint, and smooth internal line angles.
Cont…Cont…(PREPARATION)PREPARATION)Occlusal reduction of minimum 2mm for
strength.Bevels should be avoided because margins of
both composite and porcelain usually chip off.90 degrees butt joint is recommended.For esthetic blend in facial surfaces, Long
Chamfers should be placed.
Large preparationLarge preparation
Bases and LinersBases and LinersInitially Glass ionomer was used for dentinal
protection and to base the preparation to ideal form.
Now, Glass ionomer cement is recommended only for routine block out of undercuts.
ADHESIVE ADHESIVE CEMENTATIONCEMENTATIONResin luting cement is the material
recommended for this type of restoration because it bonds to enamel, dentin and restorative material.
Luting resin cement limits microleakage and enhances strength of the restoration.
PREPARING THE PREPARING THE RESTORATION FOR RESTORATION FOR BONDINGBONDINGAdhesion is more reliable in ceramic than
resin composite.Ceramics must be first etched and then silane
is applied on it to enhance wetting.Bonding to resin composite is more difficult
No air inhibited layerRelatively few unreacted methacrylate groups
ACID ETCHED DENTINACID ETCHED DENTIN
Dentin that has been treated withphosphoric acid, washed, and blot-dried with a cottonpellet. Note that the collagen layer has not collapsed.
Cont..With hybrid resin composite, intaligo surface
should be air abraded with 50 micro meter Aluminium oxide to achieve a rough surface for frictional retention.
Bonding of microfilled resin composite is more problematic.
PREPARING THE TOOTH PREPARING THE TOOTH FOR BONDINGFOR BONDINGRubber dam applied4th generation light cure adhesive should not
be used because they need to be air thinned to ensure absence of pooling of adhesive, which would prevent seating of restoration.
This air thinning also decreases bond strength.
Most research support dual cure fourth generation dentin bonding system.
ETCHING
RINSE AND DRY
DUAL CURE LUTING RESIN APPLIED
INDIRECT RESTORATION PLACED
BULK OF LUTING RESIN REMOVED
LIGHT CURE
FINISHED SURFACE
DECIDUOUSDECIDUOUSMANDIBULAR LEFT MANDIBULAR LEFT SECOND MOLARSECOND MOLAR
AFTER CARIES AFTER CARIES EXCAVATIONEXCAVATION
THE BUCCAL EXTENSION THE BUCCAL EXTENSION PREPARATIONPREPARATION
PULPAL PROTECTION
UNDERCUT ELIMINATION UNDERCUT ELIMINATION AND CUSPAND CUSPREINFORCEMENTREINFORCEMENT
The undermined cusps are reinforced with GlassIonomer Cement. All undercuts areblocked and Occlusal divergence is createdduring the placement of the cement to obtain thefeatures a cavity for inlay restoration
IMPRESSIONIMPRESSION
Rubber base impression material
PREPARATION OF THE PREPARATION OF THE INLAY ON THE CASTINLAY ON THE CAST
In increments, to reduce the polymerizationshrinkage
FINISHED INLAY
Occlusion is checked with the Maxillary cast. Occlusal adjustment are made with rotating
diamond instruments.Polished with points, cups and DISCSFinally the inlay is removed from the cast
ROUGHENING THE ROUGHENING THE UNDERSURFACE OF THE UNDERSURFACE OF THE INLAYINLAY
air abrasion inorder to enhance the bond strength
CEMENTATION OF THE CEMENTATION OF THE INLAYINLAY
TOOTH AFTER TOOTH AFTER RESTORATION USING RESTORATION USING INDIRECT TECHNIQUEINDIRECT TECHNIQUE
CAD/CAMCERAMIC RESTORATIONSComputer Aided Design / Computer Assisted
ManufacturingProcedure:
An optical impression of the prepared tooth is taken using a camera.
Next, the specific software takes the digital picture and converts it into a 3D virtual model on the computer screen.
A ceramic block that matches the tooth shade is placed in the milling machine.
An all-ceramic, tooth-colored restoration is finished and ready to bond in place.
An example of the An example of the preparation for preparation for CAD/CAM restoration.CAD/CAM restoration.
BUCCAL VIEWBUCCAL VIEW
LINGUAL VIEWLINGUAL VIEW
OCCLUSAL VIEWOCCLUSAL VIEW
With advances in software and milling materials, the newest generation of chair side CAD/CAM technology can produce restorations with lifelike esthetics and optimal fit.
By James Klim, DDS, FAGD, FADFE, PC
CROWNSCROWNS
BRIDGESBRIDGES
VENEERSVENEERS
As mentioned earliear,
the preparations for ceramic and resin composite inlays and onlays are the same.
(Fundamentals of Operative Dentistry)
pg. 514
REFERENCES:REFERENCES:Fundamentals of Operative Dentisitry 3rd Ed.
Chapter 18Considerations for the Successful Placement of
Laboratory-Processed, Indirect Composite Restorations by Gary Alex, DMD
Indirect Posterior Composite Restoration -An Extended Scope in Pediatric Dentistry by India, JSS Dental College – Mysore – Prashant S.
Simplifying CAD/ CAM Dentistry by Dr. Alex Touchstone and Dr. Randy J. Phillips