NuSmile ZR is the latest generation of pediatric restorative technology, representing an ideal balance between art and science. Made of zirconia ceramic, NuSmile ZR offers excellent natural aesthetics, supreme durability, and easy placement. NuSmile ZR and its matching Try-In crowns are part of a simple and convenient complete zirconia crown system that provides patients with the best results.

What are NuSmile ZR crowns made of?

NuSmile ZR crowns are made of high-quality Japanese monolithic Y-TZP zirconia ceramic.

Y-TZP Zirconia Ceramic – Properties

High crushing resistance (similar to steel)

High fracture toughness - 2000N. Very high stress intensity factor – indicates resistance to crack propagation and signifies the amount of energy required to initiate fracture in a material sample (so-called brittle fracture).

Fine-grained structure - Zirconium oxide crystals form fine grains of 0.2-0.5 microns. Zirconia has a very low porosity coefficient – it has a very homogeneous structure. Low porosity in tetragonal form also means that it is a non-absorbent material. High density (approx. 6g/cm3 after sintering) and lack of surface porosity translate into a reduced risk of fracture or breakage.

Biocompatibility and bio-affinity - It can be used in restorations adjacent to gold, steel, and pressed porcelain. It does not cause allergic reactions. Additionally, patients are safely diagnosed in MRI examinations.

Low tendency for bacterial plaque accumulation

Good insulator - No thermal conductivity also means no tooth hypersensitivity!

Low self-weight - Zirconia is a light material compared to precious metals. No interaction with other dental materials.

High hardness - Zirconia hardness is approximately 1250 Hv on the Vickers scale. For comparison, the value for gold is 200-260, for non-precious alloys 300-350, and for traditional porcelain 380.

Refractoriness - The melting point of zirconia is 2700 degrees C.

Relative corrosion resistance - It easily covers itself with a protective layer of oxides, which prevents further oxidation. No gingival discoloration effect.

Low ability to absorb ionizing radiation

Disinfection and sterilization

Acceptable methods include cold sterilization, autoclave sterilization, or steam sterilization according to standard sterilizer manufacturer instructions.

How to properly cement a NuSmile ZR crown?

It is very important that saliva or blood do not contaminate the internal surface of zirconia crowns. For this reason, NuSmile ZR Try-In crowns are included in the kits for use during try-in (trial fitting) to avoid contamination of the NuSmile ZR crown to be used with saliva or blood. All NuSmile ZR Try-In crowns are precisely manufactured to have the same size and shape as NuSmile ZR crowns and can be reused and autoclaved for try-in. If the internal surface of a NuSmile ZR crown becomes contaminated, one of two processes is recommended to best maintain cement adhesion to the crown: blast the inside of the crown with clean aluminum oxide or clean the internal surface of the crown with Ivoclean preparation.

NuSmile BioCem® Universal BioActive RMGI cement, Ceramir, resin cement, or other resin-modified glass ionomer cement can be used for cementing NuSmile ZR crowns. The recommended product for cementing crowns in children is: Fuji Plus glass ionomer cement.

Completely fill the crown so that there are no voids during placement. If pulp therapy was performed using eugenol-based material placed in the pulp chamber, the eugenol-based material should be covered with clear glass ionomer before cementation, unless GI was used for cementation.

The NuSmile ZR crown should be passively fitted and held in place until the cement sets by itself or is light-cured.

Can a NuSmile ZR crown be shortened? If so, how?

NuSmile ZR adjustment burs can be used for circumferential reduction and embedding of the crown margin. It is important to use a light touch and a continuous stream of water. NuSmile ZR crown polishing tools should be used to restore the smooth crown surface after any adjustments.

What is the gingival reaction to NuSmile ZR crowns?

The gingival response is excellent due to the anatomically correct contours and high biocompatibility of NuSmile ZR.

With a properly fitted crown, a correct gingival response is expected within 7-10 days.