Fixed

When esthetic expectations are high and it is important that the restorations match surrounding natural dentition or other existing restorations. If bonding is necessary to retain the restoration, bond strength is weaker and less predictable than other ceramics.

Shoulder preparation not needed. A mild chamfer or a feather-edge margin is good. 1mm buccal, lingual, and occlusal reduction is ideal, but can go to .5mm in some areas when reduction is limited. Minimum occlusal reduction of 0.5 mm; 1 mm is ideal. Adjustments and polishing: Adjust full-contour zirconia crowns and bridges using water and air spray to keep the restoration cool and to avoid microfractures with a fine grit diamond. If using air only, use the lightest touch possible when making adjustments. A football-shaped bur is the most effective for occlusal and lingual surfaces (on anterior teeth); a tapered bur is the ideal choice for buccal and lingual surfaces. Polish full-contour zirconia restorations with the porcelain polishing system of your choice.

It is recommended that full-contour zirconia be cemented using a zirconia primer like Z-Prime from Bisco or Clearfil Ceramic Primer from Kuraray. Alternatively, a resin reinforced glass ionomer such as RelyX Luting cement can also be used. When a greater bond is needed due to the lack of a retentive preparation, use a resin cement like RelyX Unicam or RelyX Ultimate. Before cementing all full-contour zirconia crowns, the interior surface of the crown needs to be cleaned with Ivoclean (Ivoclar Vivadent - Amherst, NY). This is critical in assuring maximum bond strength.

Solid zirconia requires a cast gold type preparation. If adjustments are needed, use zirconia specific diamonds and rubber wheels polishing with diamond paste.

• D2740 Crown – Porcelain/Ceramic Substrate
• D6245 Pontic Porcelain/Ceramic
• D6740 Abutment Crown Porcelain/Ceramic

Bridges which include molars, Maryland style bridges, and bridges which have a short vertical height that does not allow for adequate connector height.

Anterior full-coverage crowns require a chamfer or shoulder margin. A circular shoulder is prepared with rounded inner edges or a chamfer at an angle of 10-30°: the width of the shoulder/chamfer is approx. 1 mm. Facial reduction is 1.5 – 2 mm; 1 – 1.5 mm lingual contact clearance. Incisal reduction is 1.5 – 2 mm with rounded internal line angles, and an incisal edge at least 1mm wide to permit optimum milling of the incisal edge during CAD/CAM processing.

Posterior full-coverage crown requires a chamfer or shoulder margin. A circular shoulder is prepared with rounded inner edges or a chamfer at an angle of 10-30°: the width of the shoulder/chamfer is approx. 1 mm. Occlusal reduction is 1.5 – 2 mm: axial reduction (buccal, lingual, and interproximal) is 1.5 mm with rounded internal line angles.

IPS e.max layered – can be cemented using a resin reinforced glass ionimer such as RelyX Luting cement. Or bonded using a resin cement when extra strength is needed due to lack of retention on the prep, use a resin cement such as RelyX Unicem or RelyX Ultimate.

If adjustments are needed, use fine diamonds with water and light pressure. Always remove the crown when adjusting or bond/cement crown before adjustments are made.

• D2740 Crown
• D2610 Inlay for 1 surface
• D2620 Inlay for 2 surfaces
• D2630 Inlay for 3 surfaces
• D2962 Labial Veneer
• D2783 Crown 3/4 Porcelain Ceramic (does not include veneers)

Full-cast gold crowns are contraindicated for partials and implants.

Inlays and onlays can also be fabricated as a full-cast restoration. Feather-edge margin preparations are indicated for full-cast restorations, but any margin preparation may be used.

• Panavia 21 (Must be tin plated if precious metal is used)
• Glass ionomer cement (GC Fuji, GC America)
• Zinc Phosphate Polycarboxylate Resin Ionomer cement (RelyX, 3M ESPE)

All castings are made with a metal alloy, be it non-precious, semi-precious or precious metals. Alloys are classified by their content.

• Base – contents include non-precious, Chrome Cobalt or Titanium
• Noble – consists of 25 percent precious alloy
• High Noble – consists of 60 percent precious metal with at least 40 percent being gold

Alloy type refers to the hardness and/or softness of the material.

• Type I – Extra soft
• Type II – Soft
• Type III– Hard
• Type IV – Extra Hard (Rigid)
• Non-Precious, Noble 20, White High Noble – Type IV – Very hard and rigid. These crowns are more difficult to adjust and re-polish than alloys with a high gold content.
• Full Cast 40 – Type III – Yellow high noble alloy. Brand name currently used is Argenco 40 HN.
• Full Cast 52 HN – Type III – Yellow high noble alloy. Brand name currently used is Argenco 52.
• Full Cast 75- Type III – Yellow high noble and is an upgrade from full cast 52. The gold is slightly more yellow in color. Brand name currently used Argenco 75.

• D2790 Crown Full-Cast High Noble Metal
• D2791 Crown Full-Cast Predominantly Base Metal
• D2792 Crown Full-Cast Noble Metal

Contraindicated when the patient has a metal allergy or when the size of the tooth pulp is negligibly smaller, thus compromising the tooth preparation process. It is also contraindicated when the clinical tooth crown is very short and lacks the required stability including retention that is enough to provide the space for porcelain and metal.

The ideal preparation for PFMs is a chamfer margin preparation. If a porcelain labial margin is prescribed, then a shoulder margin preparation is required.

• Panavia 21 – tin plated
• Glass ionomer cement (GC Fuji, GC America)
• Zinc Phosphate Polycarboxylate
• Resin Ionomer cement (RelyX, 3M ESPE)

If an adjustment is required on the ceramic, use a fine diamond with water and air to keep the crown cool. To contour the ceramic, polish with a pink rubber wheel and diamond polishing paste (Brasseler, Shofu, Vident).

• D2750 Crown Porcelain fused to high noble
• D2751 Crown Porcelain fused to nonprecious
• D2752 Crown Porcelain fused to semiprecious
• D6750 Crown Porcelain fused to high noble (bridge units)
• D6751 Crown Porcelain fused to nonprecious (bridge units)
• D6752 Crown Porcelain fused to semiprecious (bridge units)

Bruxism and parafunction, Pathology of bite, more than 50% of enamel affected by pathology

For facial reduction three wheel diamond depth cutter should be used for orientation grooves. For proximal reduction - round end tapered diamond bur is used as an extension for facial reduction.

Bruxism and parafunction, Pathology of bite, more than 50% of enamel affected by pathology.

For facial reduction three wheel diamond depth cutter should be used for orientation grooves. For proximal reduction - round end tapered diamond bur is used as an extension for facial reduction.