indirect restorations haris

Haris MehmoodFinal year BDS

786haris@gmail.com

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