All Ceramic Crown (Porcelain Jacket Crown) PDF 2024

# ALL CERAMIC CROWN (PORCELAIN JACKET CROWN) Dr. Hala M. Alhawij. BDS. MSc University of Tripoli. 2024 ## Lecture outline: - Introduction - Advantages - Disadvantages - Indication - Contraindication - Criteria of tooth preparation ## Types of Crowns - Full metal - Porcelain fused to metal - Zircon...

# ALL CERAMIC CROWN (PORCELAIN JACKET CROWN) Dr. Hala M. Alhawij. BDS. MSc University of Tripoli. 2024 ## Lecture outline: - Introduction - Advantages - Disadvantages - Indication - Contraindication - Criteria of tooth preparation ## Types of Crowns - Full metal - Porcelain fused to metal - Zirconia - All-ceramic/All-porcelain ## Definition: A non - metallic Extra coronal restoration covering the prepared clinically crown, and restoring anatomy esthetics, and function. ## Introduction: The most statically pleasing fixed restoration. Because there is no metal understructure to block light transmission, it can resemble natural tooth in term of color and translucency then can any other restoration. Since it made entirely from ceramic substance, it is the weakest type of crown restoration (more susceptible to fracture). It isn't conservative type of crowns. MOST OF THE TIME it used as single restoration on the upper or lower incisors. ### Synonyms: - All ceramic crown. - Complete ceramic crown. - Porcelain Jacket crown. ## Advantages: 1. Superior esthetic. 2. Good tissue response even for subgingival margins. 3. Slightly more conservative of facial wall. 4. Can be used as single restoration only. 5. Favorable distribution of occlusal load. ## Disadvantages: 1. Reduced strength compared to Metal crowns because of the absence of metal substructure they are more susceptible to cracking or breaking 2. Significant reduction less conservative because of the need for shoulder type margin all around 3. Difficulty in obtaining will fitting margin marginal integrity not as high as all metal crowns 4. All ceramic crowns are more likely to cause wear on the opposing dentition ## Indications: 1. High esthetic requirements. 2. Considerable proximal caries. 3. Endodontically treated teeth with post & core. 4. Tooth with sufficient coronal structure (Inside edge responsibly intact). ## Contraindication: 1. When superior strength is required 2. Thin teeth Facio lingually. 3. Unfavorable distribution of occlusal load. 4. Insufficient coronal tooth structure for support. (Very short teeth) 5. Edge to edge occlusion. 6. Bruxism ## Tooth Preparation ### Armamentarium: - Handpiece. - Flat end tapered diamond. - Small wheel diamond or flame shaped diamond or football ball shaped diamond. - Long needle bur. - Four fine grit flat end tapered (fishing bur). - Binangle chisel. ## ISO classification of dental burs | Number | Description | |---|---| | 806 | Material | | 314 | Shank and Overall Length | | 198 | Shape | | 514 | Grit Size | | 014 | Head Diameter | ## Shapes of Dental Burs - Ball - Spear - Conical - Double Cone - Flame - Upside-down Cone - Football - Veneers - Pear - Cylinder - Wheel - Torpedo ## Putty silicon index made before tooth preparation. - It serves as a guide and used for verification of preparation. - Elastomeric impression material (base and catalyst). ## Recommended reduction for all ceramic crown (Porcelain jacket crown) - 1mm width shoulder finish line. - 1.5mm in incisal reduction (with a slight palatal inclination in the upper incisors and labial inclination in the lower incisor. ## Reduction 1.5mm is necessary to provide esthetic and adequate strength restoration. - 45° towards lingual surface. ## Incisal reduction - 3 depth grooves approximately 1.3mm using a flat in tapering diamond bur to allow additional loss during finishing. - Tooth structure between the grooves should be reduced. ## Incisal reduction should be perpendicular to the plane of the incisal half of labial reduction. - Inadequate incisal reduction results in poor incisal translucency of the finished restoration. ## Labial (Facial) Reduction - Placing depth orientation groove. - Depth of grooves should be 0.8mm as at finishing become 1mm. - Reduce the area between Grooves. - Two planes in preparation to provide adequate esthetics without affecting pulp. - 1st Plane is on incisal 2/3. - 2nd Plane is on gingival 1/3. ## Labial Reduction: ### Incisal 2/3 plane: - DOG (1mm) are placed this grooves should be parallel to the inclination of this area/ - Any tooth with structure between DOG were then removed with flat end tapered diamond bur. ## Gingival1/3 plan: - DOG (1mm) are placed in gingival part of labial surface parallel to the long axis of the tooth. - Any tooth structure between the DOG should be removed using a flat end tapered diamond stone to create shoulder finish line. - Supra -gingival shoulder finish line at margins are preferred. ## If the facial surface is prepared in one plane that is parallel to the incision to 2/3rd the facial surface will be over prepared and too close to the pulp - If the facial surface is prepared in one plane that is parallel to the gingival 1/3rd there will be insufficient space for porcelain in the incisal area ## Palatal reduction: - Lingual axial reduction: This is preparing the cervical portion of the lingual surface - DOG of 0.8mm placed parallel to the long axis of the tooth/ flat end T.F.B is used to reduce this area using the same angle to create shoulder F.L> - Lingual fossa reduction: - DOG of 0.8 millimeter placed in the center. - Small wheel bur or football shaped diamond bur is used (following the inclination of the tooth to reduce this area). ## Proximal reduction: - Long thin tapering diamond/ long needle diamond is used to open a space to allow for the reduction of the proximal surface without endanger the adjacent tooth. - The two proximal surface must converge only slightly 6 degree toward the incisal edge which is ideal for retention. ## Finishing preparation: - Rounding line angles and smoothening the preparation was done using fine sand taper with flat and the stone. | CRITERIA | DESCRIPTIONS | CORRECT ANSWER | |---|---|---| | Occlusal Clearance | Is the occlusal clearance adequate? | 2 mm | | Taper | Facial View: How much is the taper of the crown? | 6-12 degree | | Proximal Clearance | Proximal View: How much is the taper of the crown? | 6-12 degree | | Path of insertion | Is proximal clearance present both mesially and distally? | Yes, 0.5-1mm | | Finish | Can you see a uniform outline around the tooth?/ Undercuts are absent? | Yes | | | | | | Finish | Rounded angles/edges | Yes | | | | | | Finish | J-shaped margins | No | | | Adjacent tooth damage | No | | | Adjacent soft tissue damage | No | | | Burn marks | No | | CRITERIA | DESCRIPTIONS | CORRECT ANSWE | |---|---|---| | Finish Line | If the finish line even throughout? | Yes | | | Lingual: Would you classify the finish line as Chamfer? | No | | | Buccal: Would you classify the finish line as Shoulder? | Yes | | | Facial: Depth of finish line (Axial Reduction) | 1 mm | | | Lingual: Depth of finish line (Axial Reduction) | 1 mm | | | | | | Margin | Is the margin supragingival? | Yes | | | Is your margin parallel to the marginal gingiva? | Yes | | | | | | Occlusal reduction | Is the occlusal surface anatomically reduced? | Yes | | | Is the occlusal surface flat? | No | | | Is the occlusal surface under-reduced? | No | | | | | | Functional cusp bevel | Is there a bevel on the functional cusp? | Yes | ## ALL CERAMIC ANTERIOR CROWN PREPARATION - Rounded line angles- 2mm incisal reduction - No undercuts - Imm buccal reduction - Taper - parallel to 12 per wall - Imm BL incisal width - No I margins - Imm lingual reduction - 2imm lingual wall height 0.5mm supragingival margin height - 20.5mm, 5mm margin width # METAL CERAMIC CROWN (PORCELAIN FUSED TO METAL) ### Synonyms: - Porcelain fused to metal. - Veneered crown. - Full veneered crowns. ## Introduction: - The metal-ceramic restoration, also called a porcelain-fused-to-metal (PFM) restoration, such a restoration combines the strength and accurate fit of a cast metal crown with the cosmetic effect of a ceramic crown. - With a metal substructure, metal-ceramic restorations have greater strength than restorations made of the ceramic alone. - To be successful, a metal-ceramic crown preparation requires more tooth reduction wherever the metal substructure is to be veneered with dental porcelain. - The metal should be 0.3 to 0.5 mm thick if it is a noble metal alloy, while a metal coping made of the more rigid base metal alloys can be thinner to 0.2 mm. ## The metal coping in a metal-ceramic restoration is covered with two or three layers of porcelain: 1. Opaque porcelain conceals the metal underneath, initiates the development of the shade, and plays an important role in the development of the bond between the ceramic and the metal. 2. Body porcelain, or dentin, makes up the bulk of the restoration, providing most of the color or shade. 3. Incisal porcelain, or enamel, imparts translucency to the restoration. ## Advantages: - Good aesthetic. - Both porcelain and metal are extremely durable dental materials that can withstand the pressure of chewing for long periods of time ## Disadvantages of PFM crown: 1. Less conservative type (sufficient tooth reduction is required for both metal and ceramic material). 2. Subject to fracture because of the brittle picture of Porcelain. 3. Shared selection can be difficult. 4. Inferior aesthetic compared to worsening jacket crown. 5. Discoloration of the gingival margin may occur with time. 6. More expensive. ## Indications of PFM crown: - teeth need to be completely covered for esthetic demand, carious teeth, the malposition teeth, beg shaped lateral incisor, colored teeth, fractured teeth, teeth with large filling. - As a retainer for Fpd because it's metal substructure can accommodate cost or soldered connectors. - As a retainer to support removable partial denture. - Recontouring of minor mal-inclinations. - On endodontically treated teeth in conjunction with post core. - Implant superstructure. - Patient with unfavorable distribution of the occlusion loads (Edge to Edge Bite, Cross Bite, Deep Bite) where all ceramic is contraindicated. ## Preparation of porcelain fused to metal: - Shoulder finishing line - Facial: ≥0.5 mm, ≥0.3 mm, ≥1.2 mm, ≥1.5 mm - Lingual: ≥1 mm, ≥0.5 mm - 2 mm incisally ## Posterior teeth: - Shoulder finishing line - Buccal: ≥0.3 mm, ≥1.2 mm - Lingual: ≥0.6 mm - 1.5 mm buccally - 1.3-1.7 mm 0.8-1.2 mm 1.3-1.7 mm - Occlusally; if veneered: 2 mm non-functional cusps 2.5 mm functional cusps ## Without the space for a sufficient thickness of ceramic material, two things can happen: - The restoration will poorly contours, adversely affecting both the cosmetic effect of the crown and the health of the surrounding gingiva. - The shade and translucency of the restoration will not match adjacent natural teeth. ## Two incisal orientation grooves that are 1.8 mm deep - Incisal reduction flat-end tapered diamond - Reduce the incisal edge by 2 mm. - Remove the remaining tooth structure between depth grooves ## Labial reduction Incisal half, flat-end tapered diamond - Remove the tooth structure remaining between the orientation grooves ## Anterior PFM preparation: - The labial reduction is carried out in two planes: the gingival portion to parallel the long axis of the tooth, the incisal portion to follow the normal facial contour. ## Gingival half, flat-end tapered diamond - Remove the remaining tooth structure between depth grooves creating a shoulder at the cervical margin ## Lingual reduction wheel- or football-shaped diamond - Reduce the lingual concavity of the lingual surface with wheel-shaped or football-shaped diamond to provide adequate clearance for the restorative material. - Typically, 1 mm is required if the centric contacts in the completed restoration are to be located on metal. When contact is on porcelain, additional reduction will be necessary. ## Lingual axial reduction diamond bur to obtain finishing line - Round-end tapered diamond used to obtain chamfer finishing line in the lingual surface ## axial Reduction of the Proximal Surfaces: - Reduce the proximal surfaces with the diamond held parallel to the intended path of withdrawal of the restoration. - These walls should converge slightly from cervical to incisal/occlusal. - A taper of approximately 6 degrees is recommended. ## Finishing: - Shoulder - Marginal integrity - Structural durability - Vertical lingual wall - Retention and resistance - Concave cingulum reduction - Structural durability - Axial reduction - Retention and resistance - Structural durability - Rounded angles - Structural durability - Rounding of any sharp angles on the incisal edges and all around the prepared tooth.