Luting Agents and Cementation Procedures - PDF Dental Textbook

LUTING AGENTS AND C E M E N TAT I O N P R O C E D U R E S D R. A D H A M N I YA Z I CHAPTER 31 Luting Agents and Cementation procedures Pages 909-927 C E M E N TAT I O N Cement: a material that on hardening will fill a space or bind adjacent objects Cementation: the process of attaching pa...

LUTING AGENTS AND C E M E N TAT I O N P R O C E D U R E S D R. A D H A M N I YA Z I CHAPTER 31 Luting Agents and Cementation procedures Pages 909-927 C E M E N TAT I O N Cement: a material that on hardening will fill a space or bind adjacent objects Cementation: the process of attaching parts by means of cement Luting agent: any material used to attach or cement indirect restorations to prepared teeth OUTLINE Ideal properties Classifications Types of cement Comparisons of luting agents Procedure techniques OUTLINE Ideal properties Classifications Types of cement Comparisons of luting agents Procedure techniques IDEAL PROPERTIES Adhesion to restorative material Adequate strength to resist functional forces Lack of solubility in oral fluids Low film thickness Biocompatible Possession of anicariogenic properties Radio-opaque Ease of manipulation Esthetic and color stable OUTLINE Ideal properties Classifications Types of cement Comparisons of luting agents Procedure techniques  C L A S S I F I C AT I O N According to ingredients: Water Based Oil Based Resin Based -Glass Ionomer -Zinc Oxide -Composite Cement Eugenol -Adhesive -Resin Modified -Zinc Oxide Resins Glass Ionomer Non-Eugenol -Compomer -Zinc Polycarboxylate -Zinc  C L A S S I F I C AT I O N According to function: Function Cement Zinc Phosphate, Zinc Polycarboxylate, Definitive Cement Composite Resin, Glass Ionomer Temporary Cement Zinc Oxide Eugenol/Non-Eugenol Zinc Phosphate, Zinc Polycarboxylate, High Strength Composite Resin, Glass Ionomer Low Strength Zinc Oxide, Calcium Hydroxide Temporary Filling Zinc Oxide, Zinc Polycarboxylate Liners Calcium Hydroxide Varnishes Resin In A Solvent  C L A S S I F I C AT I O N According to matrix type: Matrix Cement Phosphate Zinc Phosphate Zinc Oxide Eugenol Phenolate Calcium Hydroxide Zinc Polycarboxylate Polycarboxylate Glass Ionomer Polymethyl Methacrylate Resin Dimethyl Methacrylate Adhesive RMGI Hybrid Ionomer  C L A S S I F I C AT I O N According to mechanism: Mechanism Cement -Cement fills the restoration-tooth gap and holds by engaging in small Non-Adhesive irregularities -Example, zinc oxide, zinc phosphate -Surface irregularities are inhanced by Micromechanical air abrasion or acid etch -Improves the frictional retention Bonding -Example, resin cements -chemical bond formation between cement and tooth structure Molecular Bonding -example, zinc polycarboxylate, glass ionomer OUTLINE Ideal properties Classifications Types of cement Comparisons of luting agents Procedure techniques TYPES OF CEMENTS Zinc phosphate Zinc polycarboxylate Zinc oxide eugenol Glass ionomer Resin modified glass ionomer Resin TYPES OF CEMENTS Zinc phosphate Zinc polycarboxylate Zinc oxide eugenol Glass ionomer Resin modified glass ionomer Resin Z I N C P H O S P H AT E Reaction: Zinc oxide (powder) reacts with the phosphoric acid (liquid) ——> zinc aluminophosphate gel Exothermic reaction Z I N C P H O S P H AT E Mechanical (non-adhesive) Indication Contraindication -Cast Crowns -Ceramic Inlays -Metal Ceramic -Ceramic Veneers Crowns -Resin Bonded FDP -Cast Posts Z I N C P H O S P H AT E Advantages Disadvantages -Strength to maintain -Irritating effect on the restoration the pulp -mixed early and set -lack of anticariogenic sharply properties -lack of adhesion to the tooth Z I N C P H O S P H AT E Mixing Time 1.5 - 2 Min Working Time 5 Min Setting Time 5 - 9 Min Film Thickness 25 micrometer Z I N C P H O S P H AT E Frozen glass slab technique To prolong working time and shorten setting time Glass slab cooled at 6oC - 10oC 50-70% more powder incorporation Working time is increased by 4-11 mins Setting time shortened by 20-40% Z I N C P H O S P H AT E Modified zinc phosphate cements Copper and silver cements Higher solubility Lower strength Fluoride cements Higher solubility Stannous fluoride 1-3% TYPES OF CEMENTS Zinc phosphate Zinc polycarboxylate Zinc oxide eugenol Glass ionomer Resin modified glass ionomer Resin Z I N C P O LY C A R B O X Y L AT E Reaction: Zinc oxide (powder) reacts with the polyacrylic acid (liquid) ——> polymer chain of carbonyl groups and polyacid groups Z I N C P O LY C A R B O X Y L AT E Molecular bonding (2 MPa) Indication Contraindication -Ceramic Inlays -Cast Crowns -Ceramic Veneers -Metal Ceramic -Resin Bonded FDP Crowns -Cast Post Z I N C P O LY C A R B O X Y L AT E Advantages Disadvantages -Low irritation -Lower compressive -Chemical bond to strength tooth structure -Difficult to clean -Easy manipulation -Surface must be -Adequate strength clean for adhesion -Low solubility -Short working time -Anticariogenic Z I N C P O LY C A R B O X Y L AT E Mixing Time 30-40 Sec Working Time 2.5 Min Setting Time 6 - 9 Min Film Thickness 25 micrometer Z I N C P O LY C A R B O X Y L AT E Polyacrylic acid react with the tooth surface calcium and chelates (bonding) Zinc polycarboxylate have different flow properties than zinc phosphate, exhibiting thinning with increased shear rate Weak bond with gold and porcelain but good bond with non-precious alloys TYPES OF CEMENTS Zinc phosphate Zinc polycarboxylate Zinc oxide eugenol Glass ionomer Resin modified glass ionomer Resin ZINC OXIDE EUGENOL Reaction Zinc oxide (powder) reacts with acid eugenol (liquid) ——> Zinc eugenolate ZnO + H2O ———> Zn(OH)2 Zn(OH)2 + 2HE ———> ZnE2n + 2H2O ZINC OXIDE EUGENOL Mechanical (non-adhesive) Indication Contraindication If resin cements are to Used as a temporary be used with the final cement agent cementation ZINC OXIDE EUGENOL Advantages Disadvantages -Sedative effect on -Low strength pulpal tissue -Disintegration in oral -Good sealing ability fluids -Resistance to -Less anticariogeNic marginal penetration -Highest solubility Good thermal insulation ZINC OXIDE EUGENOL Mixing Time Until Homogeneous Affected By Temp. & Working Time Moisture Setting Time 4 - 10 Min Film Thickness 25 micrometer ZINC OXIDE EUGENOL Classification according to ADA specification no. 30 Type I: temporary cement Type II: definitive cement Type III: temporary restoration and thermal insulating base Type IV: cavity liner ZINC OXIDE EUGENOL Powder : Liquid: 4:1, 6:1 (by weight) Two paste: same amount Affected by moisture and temp. Sets faster in oral cavity Reversible reaction TYPES OF CEMENTS Zinc phosphate Zinc polycarboxylate Zinc oxide eugenol Glass ionomer Resin modified glass ionomer Resin GLASS IONOMER Reaction Silicate glass (powder) reacts with polyacrylic acid (liquid) ——> glass ionomer GLASS IONOMER Molecular bonding (3-5 MPa) Indication Contraindication -Cast Crowns -Metal Ceramic -Ceramic Restorations Crowns -Resin Bonded FDP -Cast Post GLASS IONOMER Advantages Disadvantages -Bonding Property -Low Flexural -Anticariogenic Effect Strength -Easy To Use -High Modulus Of (Capsule) Elasticity -Different Shades -Absorbs Water -Biocompatible During Setting Phase -Good Marginal Seal -Less Esthetic GLASS IONOMER Mixing Time Depend On Type Working Time 3 - 5 Min Setting Time 5 - 9 Min Film Thickness 25 micrometer GLASS IONOMER Powder : liquid (follow instruction) Capsule type (like amalgam) Two paste system (mix homogeneous) GLASS IONOMER Sensitive to water and air When exposed to ambient air it will craze and crack ——> cohesive failure from micro crack formation Smith D.C. The cause of post cement sensitivity —> bacterial invasion, hydraulic pressure and acidity in the early setting stage and wash of thin mix. TYPES OF CEMENTS Zinc phosphate Zinc polycarboxylate Zinc oxide eugenol Glass ionomer Resin modified glass ionomer Resin RESIN MODIFIED GLASS IONOMER Reaction Radio-opaque fluroaluminosilicate glass and micro encapsulated potassium sulfate (powder) reacts with polycarboxylate acid modified with methacrylate groups, 2 HEMA and tartaric acid (liquid) ——> acid/base glass ionomer reaction with a self cured or light cured polymerization of the methacrylate group RESIN MODIFIED GLASS IONOMER Molecular bonding >10 MPa Indication Contraindication -Cast Crowns -Metal Ceramic Crowns -Ceramic Restorations -Cast Post -Resin Bonded FDP -The Material Of Choice For Casted Restorations RESIN MODIFIED GLASS IONOMER Advantages Disadvantages -Set On Demand -Lower Flexural -Immediate Finishing Strength -Better Esthetics -High Modulus Of -Higher Tensile Elasticity Strength -Absorbs Water -Anticariogenic During Setting Phase Bond To Resin But Less Than GI Composite -Less Esthetic RESIN MODIFIED GLASS IONOMER Mixing Time 8 - 10 Sec Working Time 2.5 Min Setting Time 5 - 9 Min Film Thickness 25 micrometer RESIN MODIFIED GLASS IONOMER Chemical bond The moisture sensitivity remains an issue The polyalkenoic acid plays a role starting the adhesion “diffusion based adhesion” Difficulty of removal after set TYPES OF CEMENTS Zinc phosphate Zinc polycarboxylate Zinc oxide eugenol Glass ionomer Resin modified glass ionomer Resin RESIN Reaction Polymerization reaction, combination of dimethacrylate with other monomers containing various amounts of ceramic fillers RESIN Micromechanical bonding 18-20nMPa Indication Contraindication -Light Cured Cements -All Ceramic Are Contraindicated Restorations With Metal Or Thick Zirconia Restorations RESIN Advantages Disadvantages -Excellent Mechanical -Polymerization Properties Shrinkage -High Bond Strength -Microleakage -High Esthetics -Technique Sensitive -Cleaning After Cementation Takes Time RESIN Mixing Time Depends On Type Working Time Depends On Type Setting Time 3 - 7 Min Film Thickness 20 - 60 micrometer RESIN Classification according to mechanism of matrix formation Light cured Self cured Dual cured RESIN Classification based on bonding procedure Total etch (etch + bond + resin) One step (etch & bond + resin) Self adhesive (etch + bond & resin) Self etch, self adhesive (etch, bond & resin) OUTLINE Ideal properties Classifications Types of cement Comparisons of luting agents Procedure techniques OUTLINE Ideal properties Classifications Types of cement Comparisons of luting agents Procedure techniques POWDER : LIQUID RESIN FDP C E M E N TAT I O N All-Ceramic Restoration Prepared By Dr. Yasser Mahfooz Presented by Dr. Adham Niyazi Reference  Objectives of this lecture Understanding the strengthening methods of the dental ceramic. Understanding the different between All-ceramic systems. Identify the criteria for selection of all-ceramic systems. Identify the ceramic used for all-ceramic partial fixed dental prostheses.  All-Ceramic Restoration What is the difference between metal ceramic and all ceramic tooth preparation? What are the types of all-ceramic restoration? What is the difference between porcelain and ceramic?  All-Ceramic Restoration All ceramic restorations were introduced in dentistry in order to overcome some of the problems of the metal- ceramic restorations: Poor esthetics (metal line, decrease light transmission) Decreased biocompatibility due to the allergy (Ni).  All-Ceramic Restoration All-ceramic can provide some of the most esthetically pleasing restorations currently available that have: Higher strength ceramics Adhesives for bonding the ceramic restoration to tooth structure.  All-Ceramic Restoration Basically porcelain is a type of glass - three dimensional network of silica (silica tetrahedral). It is brittle.  All-Ceramic Restoration Feldspathic porcelain 1-Feldspars are mixtures of (K2o. Al2o3.6SiO2 ) and (Na2o. Al2o3.6SiO2 ), fuses when melts forming a glass matrix. 2-Quartz (SiO2 ) fine crystalline dispersion through the glassy phase. 3-Fluxes used to decrease sintering temperature. 4-Kaolin act as a binder. 5-Metal oxides: provide wide variety of colors.  All-Ceramic Restoration Advantages of all-ceramic restorations: 1. Esthaetics. 2. Biocompatibility. 3. Chemically stable. 4. Allow for supra-gingival finish line.  All-Ceramic Restoration 1. High-strength ceramics. 2. Strengthening mechanisms of dental ceramics. 3. All-ceramic systems. 4. Selection of all-ceramic systems. 5. All-ceramic partial fixed dental prostheses  High-strength ceramics Using high strength ceramic core materials. Optimum restoration design.  High-strength ceramics Using high strength ceramic core materials: Low strength of the all ceramic restorations Two layers limited for low stress high strength core (non esthetic) veneered with a lower strength Porcelain Situations (anterior teeth) (similar to the metal ceramic technique).  High-strength ceramics Using high strength ceramic core materials: High strength ceramic core such as In-ceram alumina, In-ceram zirconia and yttrium zirconia. used as internal substructure surrounded by feldspathic ceramic produce an esthetic and strong restoration  High-strength ceramics Using high strength ceramic core materials: In-ceram Alumina framework Veneering with a feldspathic ceramic yttrium stabilized zirconia Veneering the frame work framework with a feldspathic ceramic  High-strength ceramics Optimum restoration design: Using a proper framework, selection of the abutment and coping design, such as proper thickness, no sharp line angles or point angles and proper dimension of the connectors.  All-Ceramic Restoration 1. High-strength ceramics. 2. Strengthening mechanisms of dental ceramics. 3. All-ceramic systems. 4. Selection of all-ceramic systems. 5. All-ceramic partial fixed dental prostheses  Strengthening mechanisms of dental ceramics Feldspathic ceramics are brittle materials. They are susceptible to fracture at the time of placement or during function. They contain defects from which fracture initiates related to the following: Fabrication Defects Surface Cracks  Strengthening mechanisms of dental ceramics Fabrication Defects Porosity in the glass-ceramic restorations has been shown to constitute a fracture initiation site (by micro cracks development)  Strengthening mechanisms of dental ceramics Surface Cracks Air abrasion Milling or grinding during Crack laboratory or clinical adjustment  Strengthening mechanisms of dental ceramics Methods used to improve the strength and clinical performance of dental ceramics include the following: 1. Crystalline reinforcement. 2. Chemical strengthening. 3. Glazing. Strengthening mechanisms of dental ceramics 1-Crystalline Reinforcement: Crystalline Improve the resistance of crack propagation. The ways of the crystalline reinforcement: Absorb energy Transformation Toughening  Strengthening mechanisms of dental ceramics 1-Crystalline Reinforcement: -Absorb energy Introduction of a high proportion of crystalline phase Increase the resistance of crack propagation (interruption of crack propagation). Strengthening mechanisms of dental ceramics 1-Crystalline Reinforcement -Transformation Toughening (Zirconia ) Zirconia presents in three crystallographic shapes at different temperatures: 1- Cubic (from 2680 ◦C, to 2370 ◦C). 2- Tetragonal (from 2370 ◦C to 1170 ◦C). 3- Monoclinic (from1170 ◦C to room temperature). When zirconia is alloyed with Yttria (Y2O3), the zirconia crystals retain their tetragonal shape at room temperature (Yttrium Partially Stabilized tetragonal Zirconia).  Strengthening mechanisms of dental ceramics 1-Crystalline Reinforcement -Transformation Toughening (Zirconia ) Crack occurs in the Yttria Zirconia Changes from the tetragonal to the monoclinic phase increase in the size of the crystals Compressive stresses leading to closing of the crack This is the reason of increasing strength of the Yttria Zirconia to the (900-1400 MPa).  Strengthening mechanisms of dental ceramics 2-Chemical Strengthening (feldspathic ) Replacement of small ions (Na) with larger ions (K) by diffusion from a molten salt bath during immersing ceramic. The potassium ion is 35% larger than the sodium ion. This diffusion lead to residual compressive stresses and closing the crack. Increase the flexural strength of feldspathic dental porcelain up to 80% Na K Na K  Surface porcelain strengthened by replacement of the Small Na ions by the Large K ions Na K  Strengthening mechanisms of dental ceramics 3-Glazing (protective coating): Addition of a surface glaze then fired at high temperature Low-expansion in the surface layer Cooling Compression and reduces the depth and width of surface flaws.  All-Ceramic Restoration 1. High-strength ceramics. 2. Strengthening mechanisms of dental ceramics. 3. All-ceramic systems. 4. Selection of all-ceramic systems. 5. All-ceramic partial fixed dental prostheses All-ceramic systems Inverse Proportion Esthetic Strength  All-ceramic systems Classified according to the technique of construction: 1. Platinum foil matrix technique. 2. Slip cast ceramic. 3. Heat-pressed Ceramics 4. Machined ceramic. 5. Metal reinforced systems.  All-ceramic systems 1. Platinum Foil Matrix Technique: This technique can be performed by: A. Feldspathic Porcelain (flexural strength 60 Mpa) B. Aluminous Core Ceramics (flexural strength 120-160 Mpa)  All-ceramic systems 1. Platinum Foil Matrix Technique: The first all-ceramic crown was developed by Land in 1886 and was known as the porcelain Jacket crown (PJC). The PJC was made from high-fusing porcelain utilizing platinum foil for support during firing.  All-ceramic systems 1. Platinum Foil Matrix Technique: A. Feldspathic Porcelain: Technique: 1- After impression, master cast and removable die preparation are made. 2- Platinum foil matrix is adapted on the die (including the margin area). 3- The porcelain mix (porcelain powder+ distilled water or water- based glycerin) is directly applied to the platinum foil matrix (conventional condensation technique).  All-ceramic systems 1. Platinum Foil Matrix Technique: A. Feldspathic Porcelain: Technique: 4- Introduce porcelain in the furnace (firing cycles) using the platinum foil as a tray to support the porcelain in the furnace. 5- Characterization, finishing, staining, and glazing are done.  All-ceramic systems 1. Platinum Foil Matrix Technique: A. Feldspathic Porcelain: Technique: 6- Removing platinum foil. 7- The final restoration obtained is then tried in the patient’s mouth.  All-ceramic systems 1. Platinum Foil Matrix Technique: A. Feldspathic Porcelain: Indications: 1. Laminate Veneer. 2. Single anterior crown.  All-ceramic systems 1. Platinum Foil Matrix Technique: B. Aluminous Core Ceramics : Core Porcelain: Highest strength opaque porcelain 50% by weight fused alumina crystals. Body porcelain: 15% crystal alumina. Enamel porcelain: 5% crystal alumina. The resulting restorations were approximately 40% stronger than those using traditional feldspathic porcelain.  All-ceramic systems 1. Platinum Foil Matrix Technique: B. Aluminous Core Ceramics: 1. Platinum foil is adapted 2. Aluminous core Porcelain mix then applied and fired.  All-ceramic systems 1. Platinum Foil Matrix Technique: B. Aluminous Core Ceramics: 3. After firing, Body dentin porcelain is built up then Cut back of body dentin. 4. Then enamel (incisal) porcelain is built up and fired.  All-ceramic systems 1. Platinum Foil Matrix Technique: B. Aluminous Core Ceramics: 5. Finishing. 6. Staining and glazing.  All-ceramic systems 1. Platinum Foil Matrix Technique: B. Aluminous Core Ceramics: 7. Removal of platinum foil. 8. Completed restoration.  All-ceramic systems 1. Platinum Foil Matrix Technique: B. Aluminous Core Ceramics: Advantages: Simple fabrication. Improved strength compared to conventional feldspathic porcelain (95% success rate on maxillary anterior teeth)  All-ceramic systems 1. Platinum Foil Matrix Technique: B. Aluminous Core Ceramics: Indications: Single anterior crown.  All-ceramic systems 1. Platinum Foil Matrix Technique: Disadvantages Poor marginal adaptation if the platinum foil is not precisely adapted to the surface of the die. High cost of foil. Presence of Voids (improper condensation technique). Poor strength (can not be used for posterior teeth, FPDs, bruxism). Voids under SEM  All-ceramic systems Classified according to the technique of construction: 1. Platinum foil matrix technique. 2. Slip cast ceramic. 3. Heat-pressed Ceramics 4. Machined ceramic. 5. Metal reinforced systems.  All-ceramic systems 2.Slip-Cast Ceramics High-strength core frameworks for all-ceramic restorations, can be produced with a slip-casting procedure such as the In-Ceram.  All-ceramic systems 2.Slip-Cast Ceramics Technique: 1- Duplicate the working die with an elastomeric impression material, and pour it with the special refractory die material. 2- Slip is an aqueous suspension of the alumina particles in water with dispersing agents.  All-ceramic systems 2.Slip-Cast Ceramics Technique: 3- The slip is applied onto a porous refractory die which absorbs the water from the slip and leads to the condensation of the slip on the die. 4- Then firing at high temperature (1150℃ ).  All-ceramic systems 2.Slip-Cast Ceramics Technique: 5- After firing, the refractory die shrinks more than the condensed slip, which allows easy separation of the core from the refractory die.  All-ceramic systems 2.Slip-Cast Ceramics Technique: 6- The fired porous core is later glass-infiltrated, a unique process in which molten glass (aluminosilicate glass) is drawn into the pores by the capillary action at high temperature.  All-ceramic systems 2.Slip-Cast Ceramics Technique: 7- After firing, excess glass is removed and the glass infiltrated core is veneered with compatible porcelain with matching thermal expansion.  All-ceramic systems 2.Slip-Cast Ceramics 8- Excess glass is removed with diamond wheels or burs. 9- The surfaces are sandblasted with Al2O3 powder to remove any residual glass.  All-ceramic systems 2.Slip-Cast Ceramics 10- Veneering the VITA In-Ceram framework with fine-structure ceramic using the layering technique. 11- Finishing with rotary diamond instruments  All-ceramic systems 2.Slip-Cast Ceramics 12- Characterization of the shade of the veneer 13- Completed VITA In-Ceram ALUMINA crown.  All-ceramic systems 2.Slip-Cast Ceramics Two modified In-Ceram technique have been introduced: 1. In-Ceram Spinell: Contains a magnesium spinel (MgAl2O4) provide the translucency of the final restoration. 2. In-Ceram Zirconia: Contains zirconium oxide (ZrO2) provide the highest strength.  All-ceramic systems 2.Slip-Cast Ceramics A. In-ceram Alumina: Crystalline phase is Alumina (Al2O3), flexural strength (500 MPa). B. In-ceram Spinell: Crystalline phase is Magnesium Spinell (MgAl2O4), flexural strength (350 MPa). C. In-ceram Zirconia: Crystalline phase is Zirconium Oxide (ZrO2), flexural strength (600 MPa).  All-ceramic systems 2.Slip-Cast Ceramics Indications: VITA In-Ceram ALUMINA 1. Anterior and posterior crowns. 2. Only 3-unit Anterior bridge.  All-ceramic systems 2.Slip-Cast Ceramics Indications: VITA In-Ceram SPINELL 1- Anterior Crowns (abutment with no discoloration) 2- Premolars or Molars crown (not preferred)  All-ceramic systems 2.Slip-Cast Ceramics Indications: VITA In-Ceram ZIRCONIA: 1. Anterior crown (only with severely discoloured abutment) 2. Posterior crown. 3. Anterior and posterior bridge.  All-ceramic systems Classified according to the technique of construction: 1. Platinum foil matrix technique. 2. Slip cast ceramic. 3. Heat-pressed Ceramics 4. Machined ceramic. 5. Metal reinforced systems.  All-ceramic systems 3.Heat-Pressed Ceramics These restorations are also based on the lost wax technique, where the restorations are waxed, invested and pressed at high temperature. More marginal adaptation than high-strength alumina core materials. Used to fabricate frameworks, cores or full contoured crowns.  All-ceramic systems 3.Heat-Pressed Ceramics a. Leucite-based Pressed b. Lithium Disilicate-based Pressed Ceramic ( IPS Empress I ) Ceramic ( IPS Empress II, IPS e.max )  All-ceramic systems 3.Heat-Pressed Ceramics a. Leucite based pressed ceramic ( IPS Empress I ) : It contains leucite as a major crystalline phase, dispersed in a glassy matrix. Flexural strength is about 160 MPA. The material is pressed at 1150˚C.  All-ceramic systems 3.Heat-Pressed Ceramics b. Lithium silicate based pressed ceramic ( IPS Empress II, IPS e.max ): The major crystalline phase of the core material is lithium disilicate (approximately 70%). It has mean flexural strength of about 400 MPa. The material is pressed at 920℃.  All-ceramic systems 3.Heat-Pressed Ceramics Technique: 1- Wax the restoration to final contour, sprue, and invest as conventional metal casting. 2- If the veneering technique is used, only the body porcelain shape is waxed. 3- Heat the investment to 800˚C to burn out the wax pattern.  All-ceramic systems 3.Heat-Pressed Ceramics Technique: 4- Insert a ceramic ingot of the appropriate shade and alumina plunger in the space produced by sprue burnout and place the refractory investment in the special pressing furnace.  All-ceramic systems 3.Heat-Pressed Ceramics Technique: 5- After heating to 1150˚C for IPS Empress I or 920 ˚C for IPS Empress II, the softened ceramic is slowly pressed into the mold under vacuum. 6- Remove the reaction layer using ultrasonic bath.  All-ceramic systems 3.Heat-Pressed Ceramics Technique: 7- Remove the ceramic from the contact surfaces using Al2O3 air abrasion. 8- Remove the sprue, and refit it to the die.  All-ceramic systems 3.Heat-Pressed Ceramics Technique: 9- Esthetics can be enhanced by applying an enamel layer of matching porcelain or by adding surface characterization then glazing.  All-ceramic systems 3.Heat-Pressed Ceramics e.g. IPS EmpressI, IPS Empress II or IPS e.max. Advantages: 1. High esthetics. 2. Better margin. 3. High strength.  All-ceramic systems 3.Heat-Pressed Ceramics Indications: a. IPS Empress I: Single anterior crown Laminate veneer Inlays and onlays  All-ceramic systems 3.Heat-Pressed Ceramics Indications: b. IPS Empress II or IPS e. max: 1- Posterior crown. 2- Anterior crown. 3- Anterior bridges and 1st premolar replacement upto second premolar as the last abutment.  All-ceramic systems 3.Heat-Pressed Ceramics Indications: b. IPS Empress II or IPS e. max: 4- Inlays or Onlays. 5- Laminate Veneers. 6- Occlusal Veneers.  All-ceramic systems 3.Heat-Pressed Ceramics e.g. IPS EmpressI, IPS Empress II or IPS e.max. IPS Empress I IPS Empress II, IPS e.max Crystalline phase Leucite Lithium disilicate Fracture strength 160 MPa 400 MPa Indications 1. Single anterior crowns. 1. Anterior three unit FPD with the second premolar as the 2. Laminate veneers. most posterior abutment. 3. Inlays and onlays 2. Single anterior and posterior crowns. 3. Inlays and onlays. 4. Occlusal veneer. 5. Laminate veneers.  All-ceramic systems Classified according to the technique of construction: 1. Platinum foil matrix technique. 2. Slip cast ceramic. 3. Heat-pressed Ceramics 4. Machined ceramic. 5. Metal reinforced systems.  All-ceramic systems 4. Machined Ceramics We have 2 types of machined ceramic systems: A. MAD/MAM Systems (Manually Aided Designing, Manually Aided Milling) (Copy Milling) B. CAD/CAM Systems (Computer Aided Designing/ Computer Aided Milling)  All-ceramic systems 4. Machined Ceramics A. MAD/MAM (Copy Milling) a. Zirkonzhan system b. Celay system  All-ceramic systems 4. Machined Ceramics A. MAD/MAM - Resin mock-up coping is constructed then fixed to a resin template. - Milling procedure is then started from a zirconia ceramic blocks (a stylus scans the mock-up and its movement is transferred to the copying tool which mills the ceramic block)  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: 3 3 Steps Milling 1. Digitizing/ Scanning 2. Designing à Software (CAD) 1 Scanning 3. A production technology (CAM) 2 (Milling) Designing  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: CAD/CAM systems according to the components CAD/CAM classification according to the used Types of CAD/CAM ceramics  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: CAD/CAM systems according to the components 1. A digitalization tool/scanner: that transforms geometry into digital data that can be processed by the computer. This may be: Intra-oral (e.g.: scanning prepared teeth, opposing teeth, bite registration) Extra-oral (e.g.: scanning working casts and dies, wax up, impressions)  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: 1. Digitizing/ Scanning a. Intra-oral b. Extra-oral Intra-oral scanning Working cast Impression Wax pattern  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: CAD/CAM systems according to the components 2. Software (CAD): by which the restoration is designed producing a data set for the product (coping, framework, crown, bridge, laminate, endocrown, inlay, onlay, post and core) to be fabricated. 3. A production technology (CAM): that transforms the data set into the desired product by milling the ceramic block using a milling machine.  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: 2. Designing the restoration à Software (CAD) Scanning (digital Prepared teeth on Check enough impression) the screen occlusal clearance  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: 2. Designing the restoration à Software (CAD) Tracing The Margin  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: 2. Designing the restoration à Software (CAD) Designing the crown or retainers and the connector for the FPD  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: 2. Designing the restoration à Software (CAD) Check occlusion of the designed restoration by virtual articulation  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: 3. A production technology (CAM) Milling Ceramic Blocks for Milling  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: 3. A production technology (CAM) Milling Different Sizes and types of Blocks  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: 3. A production technology (CAM) Different types of blocks  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: CAD/CAM classification according to the used 1. Chair-side production (in-office milling) e.g. Cerec, E4D 2. Lab production (extra-oral scanner) e.g. Cerec In Lab (Ineos scanner), Procera, Zirkonzhan, Kavo everest, Cercon-smart 3. Centralized fabrication in a production center (intra-oral scanner + lab milling) e.g. Cerec, E4D, I-Tero, Terios 3-shape  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: The size of the frameworks is precisely increased to allow for the shrinkage that occurs during sintering. Once a framework has been sintered. it is veneered with layered esthetic porcelains in a manner similar to that for the metal ceramic technique.  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: 1. Chair-side Production (in-office milling): All components of the CAD/CAM system are Cerec located in the dental clinic. No need for laboratory procedure. Impression using intra-oral camera. This saves time and offers the patient indirectly fabricated restorations at one appointment. E4D E.g. Cerec , E4D  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: 2. Lab production (extra-oral scanner): A conventional final impression should be send it to the laboratory. The remaining CAD/CAM production steps are carried out completely in the laboratory with the assistance of an extra-oral scanner. E.g. Cerec In Lab (Ineos scanner), Procera, Zirkonzhan, Kavo everest, Cercon-smart  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: 2. Lab production (extra-oral scanner) e.g. Cerec In Lab (Ineos scanner), Procera, Zirkonzhan, Cercon-smart Cerec In Lab system  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: 2. Lab production (extra-oral scanner) e.g. Cerec In Lab (Ineos scanner), Procera, Zirkonzhan, Cercon-smart Milling Scanner Zirkonzahn CAD/CAM system  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: 2. Lab production (extra-oral scanner) e.g. Cerec In Lab (Ineos scanner), Procera, Zirkonzhan, Cercon-smart Procera  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: 2. Lab production (extra-oral scanner) e.g. Cerec In Lab (Ineos scanner), Procera, Zirkonzhan, Cercon-smart Scanning Designing Milling Cleaning Sintering Cercon-smart  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: 2. Lab production (extra-oral scanner) e.g. Cerec In Lab (Ineos scanner), Procera, Zirkonzhan, Cercon-smart Scanning Contact scanner Shape on computer screen Procera All-Ceramic System  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: 2. Lab production (extra-oral scanner) e.g. Cerec In Lab (Ineos scanner), Procera, Zirkonzhan, Cercon-smart Milling machine Procera restorations Procera All-Ceramic System  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: 3. Centralized fabrication in a production center (intra-oral scanner + lab milling): Scanning and software designing can be performed in the clinic, then the milling takes place in a production center. Eg. Cerec, E4D, Lava, I-Tero, Terios 3-shape.  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: 3. Centralized fabrication in a production center (intra-oral scanner + lab milling) e.g. Cerec, E4D, Lava, I-Tero, Terios 3-shape Lava C.O.S. system iTero system 3 Shape TRIOS  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: Types of CAD/CAM ceramics 1. Feldspathic ceramics 2. Leucite-reinforced ceramics. 3. Lithium disilicate reinforced ceramic.  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: Types of CAD/CAM ceramics 4. Inceram Alumina blocks Galss infiltrated after milling 5. Inceram Zirconia blocks  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: Types of CAD/CAM ceramics 6. Yttrium-stabilized zirconium oxide block (900-1200 Mpa) for the CAD/CAM technique -Used for: Anterior and posterior crowns Need veneering layer Multi-unit (6 units anteriorly and 4 units posteriorly bridges) Vita In-Ceram YZ (Vita Company) IPS e. max Zir CAD (Ivoclar vivadent company)  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: Types of CAD/CAM ceramics Important Note: High strength All ceramic restorations with high opacity are indicated in the anterior region only in case of severe tooth discoloration to get the benefit of masking the discoloration from its opacity.  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: Types of CAD/CAM ceramics 7. Monolithic Yttrium-stabilized zirconium oxide block : Flexural strength: (1200-1400 MPa). Esthetic (high translucent). Used for: 1. Single anterior and posterior crowns 2. Anterior (6 units) and posterior (4 units) multi-unit bridges 3. Used as monolithic and can be milled as a full anatomic restoration so it can be used in patients with bruxism or in case of limited inter- occlusal distance.)  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: Types of CAD/CAM ceramics 7. Monolithic Yttrium-stabilized zirconium oxide block : E.g.: Prettau zirconia and High translucent Zirconia blanks, Bruxzir blocks. Prettau zirconia High translucent zirconia Milled monolithic restorations (Zirkonzahn) (Zirkonzahn) (full anatomic)  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: Types of CAD/CAM ceramics 8. Hybrid ceramic (Vita Enamic): (ceramic+ polymer network (86% wt ceramic). 1- lower brittleness than pure ceramic and better abrasion behavior than composites. 2- Clearly higher elasticity than traditional dental ceramics since the acrylate polymer network provides flexibility.  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: Types of CAD/CAM ceramics 8. Hybrid ceramic (Vita Enamic): (ceramic+ polymer network (86% wt ceramic). 3- Its dual network structure (ceramic+polymer) features a reliable crack stop function. 4- Ensures unique balance between strength and elasticity and provides high absorption of masticatory forces (suited for implant-supported crown restorations).  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: Types of CAD/CAM Ceramics Types of CAD/CAM ceramics 8. Hybrid ceramic (Vita Enamic): (ceramic+ polymer network (86% wt ceramic). Hybrid ceramic (Vita Enamic) Flexural strength: approx. 130 -140 MPa  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: Types of CAD/CAM ceramics 9. Zirconia-reinforced lithium silicate ceramic (Vita Suprinity): Vita Suprinity Flexural strength: approx. 420 MPa  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: Advantages: 1. Eliminate the uncomfortable experience of the conventional impression. (selecting trays, preparing and using materials, disinfecting impressions). In addition, digital impression avoids problems associated with the conventional impression e.g. : bubbles, inadequate margin….etc.  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: Advantages: 2. Excellent teaching tool because you can evaluate your preparation on a 19-inch monitor which also shows you if you have captured all the needed data before sending it to the lab  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: Advantages: 3. Insufficient clearance is detected immediately through a color-coded bite registration allowing corrections to be made directly, so reduce the times of restoration remake  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: Advantages: 4. When taking bite registration (centric occlusion) digitally, nothing is placed between maxillary and mandibular teeth. This reduces the risk of an inadequate inter-occlusal relationship.  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: Advantages: 5. No need to keep large amounts of impression materials and models in the office because digital scans can be stored on hard disks.  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: Advantages: 6. Sending the impression to the laboratory is a digital transfer by one of many methods such as e-mail or flash drive which saves time  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: Advantages: 7. Prevent cross infection.  All-ceramic systems 4. Machined Ceramics B. CAD/CAM: Advantages: 8. Due to the significant reduction in remakes (i.e. saving money) because all the details (adequate occlusal reduction, and the accuracy of the models, the margin of preparation) can be seen before the impression is sent to the lab (which ensures good product quality) and saving time, the CAD/CAM system is a valuable and cost effective technology.  All-ceramic systems Classified according to the technique of construction: 1. Platinum foil matrix technique. 2. Slip cast ceramic. 3. Heat-pressed Ceramics 4. Machined ceramic. 5. Metal reinforced systems.