Some dental technicians love to play with different blanks and with a combination of automated and manual work steps to meet the patient’s and indication-specific needs exactly. Others, however, would prefer a faster and more standardised path to beauty. For the latter group, Kuraray Noritake Dental has just introduced a true all-rounder: KATANA Zirconia YML. This product is based on newly developed raw materials with different yttria content integrated into the company’s multilayer colour structure. As a consequence, KATANA Zirconia YML offers colour, translucency and strength gradation throughout the blank, resulting in an unlimited indication range.

That sounds promising, but does it really work in the laboratory and clinical environment? Are there any hidden challenges with regard to design and manufacture? And how beautiful are the outcomes? In order to assess the material’s properties in real life and to see how it performs in our hands, we decided to test it clinically in treating a complex case.

Clinical procedure

The old restorations were removed, and tooth preparation was carried out (Fig. 6). Minimally invasive removal of the structure was supported by the fact that KATANA Zirconia YML has a minimum wall thickness of just 0.4 mm in the anterior and 0.5 mm in the posterior region. A digital impression was then taken with TRIOS 3 (3Shape; Fig. 7).

The acquired data was matched with photographs of the patient’s face to design a virtual wax-up (Fig. 8) and mill a temporary restoration in the dental laboratory. The placement of this temporary restoration allowed for an aesthetic and functional assessment as well as a clinical test drive of the planned definitive restorations (Fig. 9). In this set-up, the left first premolar took over the function and shape of the missing canine. The fact that the gingival margin was slightly higher in the region of the right compared with the left central incisor did not bother the patient, so alignment (gingivectomy) was not necessary.

Finishing

Individual textural features were added with hand instruments to the restorations before sintering (Figs. 14 & 15). A seamless multilayer structure without transition lines and with a warm body area was obtained. For an even more natural appearance, some individual effects and glaze were added using the CERABIEN ZR FC Paste Stain kit (Figs. 16–19).

A true all-rounder

Our test project confirmed that KATANA Zirconia YML is a high-quality material with great aesthetic potential and no limits with regard to the indication range. It is surprisingly easy to design and position the restorations in the virtual blank, and after milling, the surfaces are smooth, the margins are sharp and stable, and the fit is accurate. Micro-layering with paste stain is often sufficient for lively outcomes. This makes the new KATANA Zirconia YML the material of choice for anyone placing great value on a high level of automation, the standardisation of laboratory workflows, and efficient and easy procedures.