ExamplesIntroduction

Clinical case

Conclusion Literature

“Due to the increased aesthetic demands on behalf of patients and treatment providers, the optical impression of a reconstruction attains an increasingly higher signifi cance”1. Until now, the material of choice when it came to creating a restoration for patient with high aesthetic demands was ceramic.2 This was due to the excellent aesthetics and biocompatibility off ered by full ceramic res-torations3. However, such properties come at a price. Aside from other factors, cera-mic restorations are both labour and cost intensive to manufacture, and there is also the problem of chipping, which is caused by a high modulus of elasticity coupled with the low ductility of the ceramic material4,5. According to current data, the prevalence of bruxism amongst the adult population

stands at between 8.1 % and 31.4 %, in ad-dition to around 12.8 % for regular “sleep” bruxers6. In the light of an increasing num-ber of implant-based restorations, bearing in mind the aforementioned data on bruxism, we need to be on the lookout for a new class of materials. PEEK (polyetheretherketone), which, until now, has been somewhat over-looked in dentistry, could be the solution to our problems. Its material properties, such as its elasticity which is similar to that of bone, a shock-absorbing eff ect through so-called “stress shielding”, resistance to abra-sion, low material fatigue, biocompatibility and low plaque accretion, are very promis-ing 4,7. PEEK is approved by the industry for use as a framework material as well as for the fabrication of abutments. When used as

an abutment material in combination with a ceramic restoration, the so-called “off -peak” property reduces the stress points caused by chewing, and therefore minimises the risk of chipping. Nevertheless, further research into the various dental indications would be desirable in order to reinforce the scientifi c data. In the following case, we would like to demonstrate how the combined use of PEEK in the area of the side teeth, and ceramic in the region of the front teeth, after carefully considering the relevant material proper-ties, produces excellent results for both pa-tient and dentist.

1. Ceramic abutments – a new era in achieving optima esthetics in implant dentistry Yildirim M; Edelhoff D; Hanisch O; Spiekermann H. Int J Periodent Rest Dent 2000;

20(1):81–912. Papaspyridakos P, Mokti M, Chen CJ et al. Implant and Prostthodontic Survival

Rates with Implant Fixed Complete Dental Prostheses in the Edentulous Mandible after at Least 5 Years: A Systematic Review. Clinical implant dentistry and related research 2013, DOI: 10.1111/cid.12036

3. http://www.dgzmk.de/uploads/tx_szdgzmkdocuments/Vollkeramische_Restaurationen.pdf

4. Kern M, Lehmann F. Infl uence of surface conditioning on bonding to polyetheretherketon (PEEK). Dental materials: offi cial publication of the Academy of Dental Materials 2012; 28:1280–1283

5. Gehrke P, Alius J, Fischer C, Erdelt KJ, Beuer F. Retentive Strength of Two-Piece CAD/CAM Zirconia Implant Abutments. Clin Implant Dent Relat Res. 2013 Mar 25. doi: 10.1111/cid.12060

6. Manfredini D, Winocur E, Guarda-Nardini L, Paesani D, Lobbezoo F. Epidemiology of bruxism in adults

The patient, who has been attending our practice for some time, came to us with the request of a new restoration in her maxilla (1). Teeth 14, 11, 21, 13, and 16 were not worth saving and were extracted; socket preserva-tion (bredent, Alveolarprotect®) was carried out at the same time. The implants were successfully inserted into the maxilla three months after tooth extraction. Following a healing phase of a further four months, the implants were exposed and the remaining teeth were prepared for the prosthetic res-toration (2). The side teeth at region 14–16 and 24–27 were restored using an occlus-ally screwed crown in the form of a crown

abutment. The SKY® elegance titanium base was used in combination with BioHPP® and novo.lign® veneers (bredent®), as we want-ed to take advantage of the aforementioned advantages of PEEK, such as “stress shield-ing” and the “off -peak eff ect”, in order to avoid the risk of chipping and to provide a soft, tooth-like chewing function for our pa-tient(3–6,9). In order to satisfy the aesthetic demands of the front teeth region 13–23, we decided to create a full ceramic restoration (zirconium frame) with Willi Geller, Creation Zi-F® veneers (3–8). The SKY® elegance tita-nium base was also used for the implants, however, not as a support for BioHPP®, but

rather as an adhesive base for the manu-facture of a two-piece zirconium abutment. The harmonious integration of the resto-rations manufactured from a PEEK and ce-ramic combination was not just due to the collaboration between the dentist and den-tal technician; it was also thanks to the out-standing properties of the materials that they used. Figures 10–16 show the inserted restoration within the patient’s mouth and the results of the fi nal X-ray (17).

Taking the relevant material-specifi c prop-erties of PEEK and ceramic into account, the advantages of these materials can be com-bined at a high level to create fi rst-class res-torations. In the area of the side teeth, PEEK stands out due to the fact that it has a simi-lar elasticity to bone with its “stress shield-ing” property, in addition to an extremely

high degree of stability, and, as a result, it is able to withstand abrasion. The risk of chip-ping is therefore minimised. In the area of the front teeth, we decided to use ceramic to guarantee all of the benefi ts of the in-dividual features for aesthetic precession. Can you spot the visual diff erences between these materials? www.dr-alius.com

Excellence in reconstruction – Ziconium vs PEEK

Jochen K. Alius1 , Bernd Goller2 1Dr. med. dent., M.Sc., Private practice Nürnberg, Germany 2 MDT, Dental labarotory, FAI GmbH, Nürnberg, Germany

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