In Vitro Evaluation of Marginal Adaptation of Polyether Ether Ketone and Zirconia Copings

Abstract

Background: Polyether ether ketone (PEEK) has emerged as a new thermoplastic material with potential applications as a restorative  material.

Aim: This study aimed to evaluate the marginal adaptation of PEEK copings compared to zirconia copings using field emission  scanning electron microscopy.

Materials and Methods: A freshly extracted maxillary central incisor was prepared for a full-coverage  restoration following standard principles of tooth preparation. The tooth was sent to a laboratory for fabrication of samples using computer-aided design and manufacturing (CAD/CAM). Twenty samples of polyether ether ketone (PEEK) copings (group A) and 20 of  zirconia copings were fabricated (group B). The copings were scanned under a field emission scanning electron microscope and  measurements were taken at four distinct points. The marginal adaptation over the buccal, lingual, mesial, and distal margins for both groups was evaluated. One-way analysis of variance (ANOVA) and independent t test were applied.

Results: Our findings indicate that  PEEK showed better marginal adaptation than zirconia at all measurement points. The mean marginal gap value of the PEEK group was  33.99 ± 8.81 µm and of the zirconia group was 56.21 ± 15.07 µm. On comparing marginal adaptation among the mesial, distal, buccal, and  lingual aspects, PEEK showed better adaptation on all four margins, with the best adaptation on the buccal margin that had the lowest  mean gap value of 29.27 ± 6.07 µm. The zirconia group adapted best at the distal margin, with a lowest mean gap value of 53.58 ± 15.25  µm (P ≤ 0.05).

Conclusion: PEEK copings had better marginal adaptation and fit compared to zirconia copings. It may have applications  as a restorative material in fixed prostheses.