PREFABRICATED PROVISIONAL RESTORATIONS. DR. MOHAMMAD AL AMRI Pages:

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1 DR. MOHAMMAD AL AMRI Pages:

2 PROVISIONAL RESTORATION DEFINITION: A FIXED PROSTHESIS DESIGNED TO ENHANCE ESTHETICS, STABILIZATION AND/ OR FUNCTION FOR A LIMITED PERIOD OF TIME, AFTER WHICH IT IS TO BE REPLACED BY A DEFINITIVE PROSTHESIS (ALSO CALLED INTERIM PROSTHESIS)

3 PROVISIONAL RESTORATION PROTECTS THE PREPARED TOOTH, PRESERVES THE VITALITY OF THE PULP, ALLOWS HEALING OF THE SURROUNDING GINGIVAL TISSUE AND ADJACENT EDENTULOUS MUCOSA AND SECURES PATIENT COMFORT

4 PROVISIONAL REQUIREMENTS: 1. PULPAL PROTECTION 2. POSITIONAL STABILITY 3. OCCLUSAL FUNCTION 4. EASILY CLEANED 5. NONIMPINGING MARGINS 6. STRENGTH AND RETENTION 7. ESTHETICS

5 PREFABRICATED PROVISIONAL ARE USED FOR SINGLE TOOTH 1. RESIN (ANTERIOR TEETH ) CELLULOSE ACETATE POLYCARBONATE CROWN 2. METAL (POSTERIOR TEETH) ALUMINUM TIN-SILVER NICKEL-CHROMIUM

6 POLYCARBONATE CROWN USED FOR SINGLE ANTERIOR TEETH AND PREMOLARS. FREQUENTLY REQUIRES EXTENSIVE ALTERATION TO CORRECT MORPHOLOGICAL DISCREPANCIES AND IMPROPER CONTOUR.

7 THE POLYCARBONATE CROWN NEEDS RELINING WITH RESIN FOR RECONTOURING AND TO PROVIDE THE NECESSARY RETENTION

8 ARMAMENTARIUM: 1. POLYCARBONATE KIT 2. PENCIL 3. STRAIGHT HAND PIECE 4. ACRYLIC BUR 5. MOORES SAND PAPER DISC 6. CAMEL- HAIR BRUSH 7. CEMENT SPATULA 8. PLASTIC INSTRUEMENT 9. DAPPEN DISH 10. SEPARATING MEDIUM (PETROLEUM JELLY ) 11. SELF-CURE ACRYLIC RESIN 12. MILLER FORCEPS 13. ARTICULATING PAPER 14. ZINC OXIDE- EUGENOL AND MIXING PAD 15. EXPLORER & MOUTH MIRROR 16. DENTAL FLOSS

9 POLYCARBONATE CROWN (STEPS OF FABRICATION); 1. USE MOULD GUIDE PROVIDED IN THE KIT TO SELECT THE PROPER MESIODISTAL DIMENTION OF THE CROWN FORM.

10 2. PLACE THE SELECTED CROWN FORM ON THE PREPARED TOOTH AND MARK ON THE GINGIVAL AREA OF THE LABIAL SURFACE FOR ADJUSTING THE LENGTH

11 3. THE EXCESS LENGTH IS TRIMMED AWAY WITH ACRYLIC BUR USING THE PENCIL AS THE REFERENCE MARK. INTERPROXIMAL AREA CAN ALSO BE ADJUSTED IF IT IS TOO TIGHT.

12 4. APPLY PETROLATUM ON THE PREPARED TOOTH AND ALSO ON THE ADJACENT TEETH. 5. MIX SELF CURE ACRYLIC RESIN IN A DAPPEN DISH.

13 POLYCARBONATE CROWN IS AVAILABLE IN ONE SHADE ONLY. IT IS POSSIBLE TO MODIFY THE SHADE BY APPROPRIATE SELECTION OF THE SHADE OF THE ACRYLIC RESIN USED FOR THE RELINE.

14 6. USE THE PLASTIC INSTRUEMENT TO FILL THE CROWN WITH THE MIXED RESIN. 7. WHEN THE ACRYLIC RESIN BEGINS TO LOSE ITS SURFACE GLOSS, SEAT THE CROWN SLOWLY EXPRESSING ALL THE EXCESS RESIN AROUND THE MARGINS.

15 8. DO NOT ALLOW THE FINAL POLYMERIZATION TO TAKE PLACE IN THE PATIENTS MOUTH. 9. AFTER COMPLETE POLYMERIZATION, THE EXCESS AROUND THE MARGIN CAN BE TRIMMED WITH ACRYLIC BUR.

16 10. CHECK OCCLUSION USING ARTICULATING PAPER AND ADJUST IT.

17 11. SMOOTH OUT THE ROUGH ABRADED AREAS WITH MOORES SAND PAPER DISC. 12. POLISH ALL SURFACES WITH POLISHING COMPOUND OR WITH SLURRY OF PUMICE.

18 POLYCARBONATE CROWN CAN ALSO BE FABRICATED BY THE INDIRECT TECHNIQUE ON THE CAST.

19 CEMENTATION IS DONE WITH ZINC OXIDE- EUGENOL CEMENT.

20 PROVISIONAL CROWN FOR AN ENDODONTICALLY TREATED TOOTH IT IS DIFFICULT TO FABRICATE A PROVISIONAL RESTORATION FOR A TOOTH THAT HAS BEEN PREPARED FOR A DOWEL CORE BECAUSE VERY LITTLE SUPRAGINGIVAL TOOTH STRUCTURE LEFT INTACT.

21 STANDARD POLYCARBONATE WITH AN ALUMINUM POST (PARAPOST SYSTEM) OR PAPER CLIP OR A STIFF WIRE PLACED IN THE CANAL

22 AFTER POST SPACE PREPARATION, AN ALUMINUM POST PLACED IN THE ROOT CANAL. POLYCARBONATE CROWN OF THE APPROPRIATE SIZE IS RELINED WITH ACRYLIC RESIN. ONCE THE RESIN SETS THE POLYCARBONATE CROWN WITH THE ALUMINUM POST BECOMES A SINGLE UNIT.

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26 PREFORMED ANATOMIC METAL CROWN THERE ARE SEVERAL SYSTEMS AVAILABLE UTILIZING THE SAME GENERAL PRINCIPLES

27 THE PROCEDURE CONSISTS OF: 1. MINIMAL TOOTH PREPARATION 2. MEASUREMENT AND SELECTION 3. TRIMMING AND ADAPTATION OF GINGIVAL MARGIN 4. OCCLUSAL ADJUSTMENT 5. CEMENTATION

28 ARMAMENTARIUM: 1. NO :170 BUR 2. MEASURING GAUGE 3. CROWN FORMS 4. STRETCHING BLOCK 5. CROWN AND BRIDGE SCISSORS 6. CONTOURING PLIERS 7. MOORES SAND PAPER DISC 8. ARTICULATING PAPER 9. MILLER FORCEPS 10. CEMENT SPATULA 11. ZINC OXIDE-EUGENOL CEMENT AND MIXING PAD 12. PETROLATUM 13. BURNISHER, EXPLORER & MOUTH MIRROR 14. DENTAL FLOSS

29 MINIMAL TOOTH PREPARATION

30 MEASURING GAUGE IS USED TO OBTAIN THE MESIODISTAL DIMENTION OF THE CROWN SPACE

31 GINGIVAL MARGINS CAN BE FLARED SLIGHTLY ON THE STRETCHING BLOCK

32 MARGINAL RIDGE HEIGHT DISCREPANCY BETWEEN THE RESTORATION AND THE ADJACENT TEETH IS ESTIMATED

33 EXCESS HEIGHT IS REMOVED FROM THE GINGIVAL MARGIN

34 THE GINGIVAL MARGIN IS SMOOTHED WITH MOORES SAND PAPER DISC

35 AXIAL CONTOURS ARE CONTOURED WITH PLIERS

36 OCCLUSION IS CHECKED WITH ARTICULATING PAPER

37 CROWN IS FILLED WITH ZINC OXIDE-EUGENOL CEMENT AND SEATED INTO PLACE.

38 MARGINS ARE BURNISHED

39 EXCESS CEMENT IS REMOVED FROM THE INTERPROXIMAL AREA WITH DENTAL FLOSS

40 THE REMAINING CEMENT IS REMOVED FROM THE GINGIVAL CREVICE WITH AN EXPLORER

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