PROVISIONAL RESTORATION OR

TEMPORIZATION

Under the guidance of:Dept. Of Prosthodontics and Crown and Bridge

NORTH BENGAL DENTAL COLLEGE AND HOSPITAL

• DEFINITION: A fixed or removal prosthesis designed to

enhance esthetics stabilization and function for a limited period of time after which it is to be replaced by definitive prosthesis.( GPT- 8 )

• SYNNONYMS: Temporization, interim prosthesis, provisional

prosthesis.

Why provisional restoration needed???• Provisional restoration is given for a period of

time until a permanent arrangement can be made.

• To protect the prepared tooth and kept patient comfortable.

• By successful treatment with provisional restoration dentist can get the patient confidence which is an influencing factor for success in the final restoration.

IDEAL REQUIREMENTS OF PROVISIONAL RESTORATION

Three basic requirements :• Biologic requirements Pulp protection Periodontal health Positional stability Prevention of fracture

• Mechanical requirements Function Loss of retention Removal of reuse

• Esthetic requirements Colour compatibility Translucency Colour stability

BIOLOGIC REQUIRMENTS PULP PROTECTION: During tooth preparation the dentinal tubules are exposed. Thus provisional restoration should protect the prepared tooth from oral environment, thereby preventing sensitivity and irritation to pulp.

PERIODONTAL HEALTH:It should have good marginal fit,proper contour and smooth surface to preventaccumulation of plaque,facilitate easy plaque removal and maintain periodontalhealth.

BIOLOGIC REQUIRMENTS POSITIONAL STABILITY:It should provide a comfortable, stable, and functional occlusal relationship by maintaining interarch and intra-arch stability thereby preventing tooth migration ,supraeruption.

PREVENTION OF FRACTURE:It should protect the prepared tooth surface from fracture which is commonly seenin partial coverage restoration, in which margin of preparation is close to the occlusal surface of tooth and could be damaged during chewing.

MECHANICAL REQUIREMENT FUNCTIONAL:It should possess good compressive and flexural strength. The strength of materialused for fabricating provisional restoration is always much lower than that of thedefinitive restoration material.The greatest stresses in a provisional restoration occur during chewing.

LOSS OF RETENTION:It should have close adaptation to the prepared tooth surface to prevent displacementand recementation, which will increase patient visits.

MECHANICAL REQUIREMENT

REMOVAL OF REUSE:Provisional restoration may need to be removed and recemented often.If they are well fabricated with adequate thickness and cemented with weak cementCan be removed without breakage.

ESTHETIC REQUIREMENTIt should match the shape, size, colour, and texture of the restored tooth especially inthe anterior region.Colour stability is also important if the provisional are to function for a prolongedperiod.It also serves as a guide to achieve aesthetics to the final restoration.

CLASSIFICATION Provisional restorations are classified on the following basis: According to method of fabrication: Preformed Custom made

According to material used: Resin : Preformed (Polycarbonate, Cellulose acetate) Custom made (Acrylics, Bis-acryl composites) Metals: Preformed (Aluminium, Tin silver, Nickel chromium) Custom made (Cast metal alloy)

According to duration of use: Short term. Long term.

According to technique of fabrication: Direct technique. Indirect technique.

PROVISIONAL RESTORATION MATERIAL IDEAL REQUIRMENTS OF PROVISIONAL RETORATIVE MATERIAL: Adequate strength and wear resistance. Biocompatible. Good dimentional stability. Easy to contour and polish. Odourless and non-irritating. Chemically compatible with luting cement. Esthetically acceptable. Adequate working and setting time. Easy to repair.

PROVISIONAL RESTORATION MATERIAL MATERIALS USED: Resin : Acrylics Polymethyl methacrylate Ploy-R’ methacrylate Bis- acryl composites Chemically activated Light activated Dual activated Metals : Cast metal alloy

Advantage & disadvantage of ploy-r methacrylate

Advantage & disadvantage of poly methyl methacrylate

Advantage & disadvantage of bis-acryl composites

PRE-FORMED PROVISIONAL RESTORATION

Depending on the Types of Material Used: Resin based provisional restoration Cellulose acetate Polycarbonate Poly methyl methacrylate Poly-R methacrylate Microfilled composite Urethane dimethacrylate

Metal provisional restoration Aluminium Nickel- Chromium Tin- Silver

RESIN:Polycarbonate crowns:They combine microglass fibers with polycarbonate plastic material.It is used as a matrix material around a prepared tooth .It possesses high impact strength, abrasion resistance, and good bond with meth acrylate resin.Best esthetic among all preformed crowns.Available in shape of incisor, canine, and premolars in varying size

Cellulose acetate:It is thin, soft, transparent scaffold material.It is available in all tooth shape and different sizes.It does not bond to the relining resin.An approximately size of this crown is selected from a mould guide and filled with autopolymerizing resin of appropriate shade. This is inserted over the lubricated prepared tooth.

METALS: Aluminium:These are generally limited to posteriors for esthetics reasons.Available as simple shell.They provide good adaptation due to softness and difficulty of the material, but can also promote rapid wear resulting in perforation.They may be relined with resin to obtain better fit and rigidity and then luted to prepared tooth. Nickel- Chromium: Indicated for use in children with damaged primary teeth.They need not to reline with resin.They are trimmed, contoured, and adapted to the tooth.Strong cements are used for luting.

TECHNIQUES OF FABRICATION

DIRECT TECHNIQUE

INDIRECT TECHNIQUE

DIRECT-INDIRECT TECHNIQUE

DIRECT TECHNIQUE

APPLICATION OF SEPARATING MEDIA ON PREPARED TOOTH PUTTY INDEX WITH RPD AND

TRIMMED FLANGE

REMOVABLE PARTIAL DENTURE IN PLACEPRE OPERATIVE PICTURE

RESIN MIXED AND POURED IN THE INDEX

MAKING PUTTY INDEX WITH THE RPD

ALLOWED TO SET RESIN WITH RPD IN THE INDEX

INDEX RESEATED IN THE MOUTH TRIMMED PROVISIONAL PROSTHESIS

INDIRECT TECHNIQUE

DIAGNOSTIC CAST WITH MISSING MANDIBULAR INCISORS ARTIFICIAL TEETH ARRANGED CAST WITH ARTIFICIAL TEETH

VACUUM FORMED

CAST FOLLOWING TOOTH PREPARATION

TOOTH PREPARATION DONETEMPLATE PLACED ON CAST TO CHECK FIT

TEMPLATE SEATED ON CAST FILLED WITH THE PROVISIONAL RESTORATIVE MATERIAL IN THE AREA OF RESTORATION

TEMPLATE REMOVEDFROM CAST AFTER POLYMERIZATION

PROVISIONAL RESTORATION TRIMMED AND FITTED ON CAST

DIRECT-INDIRECT TECHNIQUE

FINAL DIRECT INDIRECT PROVISIONAL RESTORATION

INDIRECT PROVISIONAL RESTORATION TRIMMED AND FIT ON CAST

ABUTMENT TEETH PREPARED IN PATIENT MOUTH

POLYMERIZING ACRYLIC RESIN POURED INTO PUTTY INDEXPREPARATION COMPLETE IN MODELTOOTHPREPARED MINIMALLY IN

THE MODEL

PUTTY INDEX FABRICATED

ON THE DIAGNOSTIC CAST ,EDENTULOUS AREAS ARE RESTORED AND WAX CORRECTION ARE DONE

STABILIZING RESTORATION IN PATIENT MOUTH

ACRYLIC RESIN ADDED TO RETAINER IN THE PROVISIONAL RESTORATION

PUTTY INDEX SECURED ON THE CAST BY RUBBER BAND

CEMENTATION OF PROVISIONAL RESTORATION IDEAL PROPERTIES OF CEMENT: Ability to seal against leakage of oral fluid. Strength consist with intentional removal. Low solubility. Chemical compatibility with provisional polymer. Ease of eliminating excess. Adequate working time and short setting time. CEMENTS USED: Zinc oxide eugenol. Reinforced zinc oxide eugenol. Non- eugenol cements.

Zinc phosphate, Zinc polycarboxylate, and Glass ionomer cements are not used because their comparatively high strength makes intentional removal difficult.

LIMITATIONS OF PROVISIONAL RESTORATION Lack of adequate strength—fracture of provisional is

possible in long span FPDs, patient with bruxism and reduced interocclusal clearence.

Inadequate marginal adaptation. Poor aesthetic in long term provisional restoration. Plaque accumulation due to poor surface characteristic. Compromised bonding characteristics. Mild to moderate tissue irritation

References:Contemporary fixed prosthodontics-

Rosenstiel, Land, PujimotoTextbook of prosthodontics-

V Rangarajan

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