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PEKK-made indirect temporary crowns and bridges: a clinical pilot study
T Klur1, Istabrak Hasan2,3, K Ottersbach4
1Department of Orthodontics, University of Cologne, Kerpener Str, 32 50931, Cologne, Germany.
Objectives:
The aim of the present study was to find out whether the high-performance polymer PEKK is an equivalent alternative compared to cobalt chrome (CoCr)-made restorations, regarding to biocompatibility, stability, and comfort.
Materials And Methods:
Twenty-two patients (m, 10; f, 12) who were indicated for a long-term temporary-fixed restoration were included. They were randomized through a lottery procedure into two groups: the first group was restored with veneered PEKK-made crowns and bridges (Pekkton ivory), while the second group was restored with veneered CoCr crowns. Clinical parameters (plaque index (PI), probing depth (PD), fracture, and chipping) were documented in a period of 3-5 months from the insertion of restoration. Furthermore, every patient completed the OHIP-14 questionnaire. An exchange of the restorations from the first to the alternative material was performed after a period of 3-5 months.
Results:
All patients showed an improvement of the oral hygiene and probing depth after insertion of the temporary restorations. However, there were no significant differences between PEKK and CoCr-made restorations (P > 0.05). There was no chipping after 5 months for both kinds of materials. There was a noticeable reduction of pain and discomfort of patients after insertion of temporary restorations. However, there were no significant differences between the two materials (P > 0.05).
Conclusions:
PEKK-made temporary restorations offer a good and stable alternative to CoCr-made restorations. They have a high aesthetical advantage over CoCr restoration.
Clinical Relevance:
Esthetic and price-efficient temporary crowns can be offered for the patient during periodontal therapy to improve its success, in particular by improving the oral hygiene.
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