Wear Resistance, Color Stability and Displacement Resistance of Milled PEEK Crowns Compared to Zirconia Crowns under Stimulated Chewing and High-Performance Aging

Simone Shah Abhay; Dhanraj Ganapathy; Deepak Nallaswamy Veeraiyan; Padma Ariga; Artak Heboyan; Pokpong Amornvit; Dinesh Rokaya; Viritpon Srimaneepong

doi:10.3390/polym13213761

Wear Resistance, Color Stability and Displacement Resistance of Milled PEEK Crowns Compared to Zirconia Crowns under Stimulated Chewing and High-Performance Aging

Polymers (Basel). 2021 Oct 30;13(21):3761. doi: 10.3390/polym13213761.

Authors

Simone Shah Abhay¹, Dhanraj Ganapathy¹, Deepak Nallaswamy Veeraiyan¹, Padma Ariga¹, Artak Heboyan^{1

2}, Pokpong Amornvit³, Dinesh Rokaya⁴, Viritpon Srimaneepong⁵

Affiliations

¹ Department of Prosthodontics, Saveetha Dental College and Hospital, Saveetha Institute of Medical and Technical Sciences, Chennai 600077, India.
² Department of Prosthodontics, Faculty of Stomatology, Yerevan State Medical University after Mkhitar Heratsi, Str. Koryun 2, Yerevan 0025, Armenia.
³ Golden Jubilee Medical Centre, Mahidol University, Nakon Pathom, Salaya 73170, Thailand.
⁴ Department of Clinical Dentistry, International College of Dentistry, Walailak University, Bangkok 10400, Thailand.
⁵ Department of Prosthodontics, Faculty of Dentistry, Chulalongkorn University, Bangkok 10330, Thailand.

Abstract

Recently, polyetheretherketone (PEEK) has been introduced to the dental market as a high-performance and chemically inert biomaterial. This study aimed to compare the wear resistance, abrasiveness, color stability, and displacement resistance of zirconia and PEEK milled crowns. An ideal tooth preparation of a first maxillary molar was done and scanned by an intraoral scanner to make a digital model. Then, the prosthetic crown was digitally designed on the CAD software, and the STL file was milled in zirconia (CaroZiir S, Carol Zircolite Pvt. Ltd., Gujarat, India) and PEEK (BioHpp, Bredent GmbH, Senden, Germany) crowns using five-axis CNC milling machines. The wear resistance, color stability, and displacement resistance of the milled monolithic zirconia with unfilled PEEK crowns using a chewing simulator with thermocyclic aging (120,000 cycles) were compared. The antagonist wear, material wear, color stability, and displacement were evaluated and compared among the groups using the Wilcoxon-Mann-Whitney U-test. Zirconia was shown to be three times more abrasive than PEEK (p value < 0.05). Zirconia had twice the wear resistance of PEEK (p value < 0.05). Zirconia was more color stable than PEEK (p value < 0.05). PEEK had more displacement resistance than zirconia (p value < 0.05). PEEK offers minimal abrasion, better stress modulation through plastic deformation, and good color stability, which make it a promising alternative to zirconia crown.

Keywords: CAD/CAM; PEEK; aging process; biodegradation; biomaterials; chewing simulation; color stability; crowns; dental materials; dentistry; displacement resistance; wear resistance; zirconia.