Posterior Zirconia
Zirconia is so versatile, it can be used in almost any situation from singles, bridges with any combination of abutments and pontics, inlay bridges, Maryland type bridges and screw retained implants. Also an esthetic alternative to a PFM with metal occlusion due to limited space.
Shoulder preparation not needed. A mild champfer 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 Zirlux 16+ zirconia crowns and bridges using water and air spray to keep the restoration cool and to avoid micro-fractures 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 Zirlux 16+ zirconia restorations with the porcelain polishing system of your choice.
Zirconia may be cemented using a resin reinforced glass ionomer such as Relyx Luting cement. When a greater bond is needed do to the lack of a retentive preparation, use resin cement like Relyx Unicam or Relyx Ultimate.
Before cementing all Zirconia crowns, the interior surface of the crown needs to be cleaned with Ivoclean (Ivoclar Vivadent; Amherst N.Y.). 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.