Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

All ceramic crown preparation seminar

all ceramic crown prepartion
esthetic crown
fixed prosthodontics

  • Login to see the comments

All ceramic crown preparation seminar

  1. 1. Today: we will talk about all ceramic crown preparation.
  2. 2. DefinitionDefinition • Non metallic full coverage ceramic restoration . Restoring the prepared ant. Teeth functionally & esthetically
  3. 3. • Advantages Superior esthetic
  4. 4. Excellent translucency Good tissue response Conservative reduction of facial surface Appearance of restoration influenced by color of luting agent
  5. 5. DisadvantagesDisadvantages  Absence of metal substructure Reduced strength of the restoration  Significant tooth reduction is necessary on proximal & lingual surface  Difficulty in obtaining well fitting margin
  6. 6. * Not effective as retainer for fixed prosthesis * Wear observed on functional surface of natural tooth * Wear may occur on functional surfaces of natural teeth that oppose porcelain restoration •
  7. 7.  IndicationsIndications in ant. Teethin ant. Teeth ** Discolored toothDiscolored tooth ** Tooth with enamel defectsTooth with enamel defects ** Fracture teethFracture teeth ** Bilateral proximal decay with incisalBilateral proximal decay with incisal angle involved (class 4 ).angle involved (class 4 ). ** Unilateral proximal decayUnilateral proximal decay
  8. 8. • ** Excessive attrition toothExcessive attrition tooth ** at rampant cariesat rampant caries ** malformed and rotated teethmalformed and rotated teeth *functions:*functions: **All ceramic is used as foundationAll ceramic is used as foundation restorationrestoration ** for endodontically treated teeth tofor endodontically treated teeth to overcome esthetic problem associatedovercome esthetic problem associated with metal post and core systemwith metal post and core system
  9. 9. •ContraindicationContraindication ** With posterior teethWith posterior teeth ** young patientsyoung patients → large pulp,high epithelium→ large pulp,high epithelium attachmentattachment ** Deep or heavy bitesDeep or heavy bites Bad habits ( ex. nail biting )Bad habits ( ex. nail biting ) ** If occlusal load is unfavorableIf occlusal load is unfavorable ** At long span bridgeAt long span bridge ** when other more conservative rest. iswhen other more conservative rest. is indicatedindicated
  10. 10. PrecautionsPrecautions • Over tapered prepared cingulum → ↓ Resistance & Retention → exert wedge like force thus ↑ stress causing fracture •Horizontal surface at the junction of prepared fossa & lingual wall should be preserved → reduce stresses
  11. 11. • Lingual ridge of canine not completely reduced → ↑ rotational resistance
  12. 12. Facial reductionFacial reduction Placing depth orientation groove Depth of grooves should be 0.8 mm as at finishing become 1 mm Reduce the areas between grooves Two planes in preparation to provide adequate esthetics without affecting pulp . 1st plane is on incisal two third . 2nd plane is on one-third
  13. 13. * facial reduction should extend around the facial-proximal line angles & fade out on the lingual aspect of the proximal surface * end of flat end diamond forms shoulder finishline
  14. 14. Incisal reductionIncisal reduction • reduction 1.5 : 2 mm clearance to provide esthetic & adequate strength restoration • 45 degrees towards lingual surface • 3 depth grooves approximately 1.3 mm to allow additional loss during finishing • tooth structure between the grooves should be reduced • Incisal reduction should be perpendicular to the plane of incisal half of labial reduction
  15. 15. Lingual reductionLingual reduction Cingulum reduction is done by FootballCingulum reduction is done by Football shaped diamondshaped diamond  care should be taken to prevent over atcare should be taken to prevent over at the junction between cingulum & lingualthe junction between cingulum & lingual walwal ll A short lingual wall reduces the retentionA short lingual wall reduces the retention of the restorationof the restoration
  16. 16. Proximal reductionProximal reduction * The shoulder should be at least 1.0 mm wide * care should be taken to avoid undercuts at the junction of axial walls & the shoulder finish line
  17. 17. Finishing the preparationFinishing the preparation ** All axial surfaces should be smoothed usingAll axial surfaces should be smoothed using finishing stones & bursfinishing stones & burs ** Roundation of any remaining sharp lineRoundation of any remaining sharp line angles to avoid porcelain fractureangles to avoid porcelain fracture ** Uniform width of shoulder finish lineUniform width of shoulder finish line (approximately 1mm ) to resist forces directed(approximately 1mm ) to resist forces directed from the incisalfrom the incisal
  18. 18. prepared by :prepared by : Moataz AbodiefMoataz Abodief Mostafa El-SadicMostafa El-Sadic Nour MohammedNour Mohammed Waleed MohammedWaleed Mohammed Dentistry College ; Assiut UniversityDentistry College ; Assiut University thanksthanks

×