Contest of the ceramics: Which ceramic will come out on top - IPS Style or IPS d.SIGN?

Introducing a new ceramic to your laboratory is quite an undertaking. Switching to a new ceramic system entails a series of changes: Employees need to be trained and workflows have to be reorganized. IPS Style, like its predecessor IPS d.SIGN, contains fluorapatite crystals. It additionally contains oxyapatite crystals. When a dental laboratory changes over from IPS d.SIGN to IPS Style it can expect to work with quite a number of familiar features. Nevertheless: How does IPS Style match up to the well-known IPS d.SIGN? Velimir Žujić who is a dental technician and his daughter Dr Patricija Žujić Sindik who is a dentist decided to put the two materials to the test.

In his dental laboratory in Rijeka (Croatia), Velimir Žujić routinely used the fluorapatite leucite glass-ceramic IPS d.SIGN. In 2015, IPS Style was launched on the market. The product is the first patented metal-ceramic material containing oxyapatite crystals. Since its introduction, Mr Žujić has had a number of opportunities to work with the new metal-ceramic material. Over time, he even decided to switch to using IPS Style altogether. In order to eliminate any concerns about the product, Mr Žujić and his daughter Dr Patricija Žujić Sindik thoroughly tested the new material. They wanted to find out how IPS Style really compares with IPS d.SIGN.

First test: comparison of the opaquer materials

Two metal specimens per ceramic were conditioned in different ways: one was treated with a bonding agent and the other was oxidized at 950 °C with a holding time of one minute. Subsequently, all the specimens were coated with the paste opaquer IPS d.SIGN and the powder opaquer IPS Style. At the time of the test series, IPS Style was only available in the familiar powder form. Both opaquers were easy to use and the results were excellent. In this first test round, both products performed equally well.

Second test: comparison of the layering materials

After the initial trial, the ceramics were subjected to a more stringent test: The different materials of the two ceramic systems were applied next to each other on the same metal sample. The following materials were compared: Dentin, Transpa T neutral and Opal Effect OE1. The materials were applied in parallel and then fired. The result after firing: The two different ceramics showed the same colour. They exhibited virtually the same level of fluorescence. Under a polarizing light, IPS Style looked somewhat brighter than IPS d.SIGN. The vertical shrinkage of the two ceramics was almost identical. IPS Style exhibited less horizontal shrinkage than IPS d.SIGN. The performance of IPS d.SIGN in interdental areas and deep fissures was less predictable than that of IPS Style. In terms of its dimensional stability, IPS Style showed a clear advantage: The contours of the sample were virtually unchanged after the first firing. Even though these two tests were relatively simple, they provided valuable information about IPS Style. The subsequent clinical test would clarify any further questions.

The shrinkage behaviour test samples. left: IPS d.SIGN right: IPS Style

Clinical test

Our patient Iris F. was prepared to act as the test subject for our comparison of the two ceramics. She wanted her front teeth to look more attractive. The shape and position of the teeth were to remain unchanged. All she wished for was a slightly lighter tooth colour. We took a digital impression of the preparation and ordered the model (3D printed) and the CoCr copings (SLM) in duplicate from a milling centre.

Layering

First, the metal copings were oxidized according to the instructions of the manufacturer and then the corresponding opaquer was applied. IPS d.SIGN Paste Opaquer and IPS Style Ceram Powder Opaquer exhibited excellent flow properties. The metal was completely masked after only two firing cycles. The Margin material was used to create a shoulder and establish a tight gingival margin. Both ceramics produced outstanding results.

First firing

In order to make a detailed comparison of the results achieved with IPS Style and IPS d.SIGN, all the materials were mixed with Visual Eyes Liquid (Harvest Dental) to reveal the final colour of the restoration. The two ceramics were built up in the exact same way.

After the materials had been fired, a direct comparison of IPS Style and IPS d.SIGN clearly showed the excellent colour coordination of the different ceramic ranges from Ivoclar Vivadent. The shade results of the two ceramics were identical and extremely natural-looking. The dimensional stability of the materials was impressive. A closer analysis showed that only a few distal areas of the incisal edge in the IPS d.SIGN restoration were a little more translucent. The IPS Style Ceram Transpa materials were used to adjust the translucency in a second corrective firing. The brightness of the material was easy to control.

Conclusion

IPS Style shows excellent colour and dimensional stability. The material’s fluorescent properties are comparable to those of IPS d.SIGN. They are a bit stronger in IPS Style Ceram Incisal and IPS Style Ceram Transpa T neutral. Nevertheless, the IPS Style crowns had a slight edge over those made with IPS d.SIGN. As a result, we chose them as the permanent solution for our patient. Overall, the tooth shapes were more harmonious and vital-looking in the mouth. Despite the different CTEs of the various manufacturing methods, the IPS Style materials can be used on printed, milled and cast metal frameworks. This is a great advantage, since dental technicians have to be flexible. Velimir Žujić and his daughter Dr Patricija Žujić Sindik are convinced that changing over to the new ceramic system will definitely be worth their while!