Vertical Marginal Gap Distance of CAD/CAM Milled BioHPP PEEK Coping Veneered by HIPC Compared to Zirconia Coping Veneered by CAD-On lithium disilicate “In-Vitro Study”

Abstract

Statement of problem: marginal inaccuracy causes a space between restoration and prepared tooth, which accelerates cement dissolution, leading to secondary caries, pulpal lesions, postoperative sensitivity, periodontal disease and marginal discoloration. Marginal gap should be less than 120µm. Aim: to evaluate vertical marginal gap of PEEK (Bio-HPP) veneered with CAD/CAM composite veneer (HIPC) as compared to zirconia veneered with CAD-On lithium disilicate glass ceramic. And the effect of ageing on the gap of both restorations. Material and methods: 40 extracted molars were prepared, divided into two groups, control group (ZR) (n=20), teeth restored with IPS e.max ZirCAD copings veneered with IPS e.max CAD and intervention group (PEEK) (n=20), teeth restored with breCAM BioHPP copings veneered with BreCAM.HIPC. Each specimen was photographed using Leica S8 APO stereomicroscope under magnification 32X and image analysis was done. Measurements were taken twice before and after thermomechanical cycling. Results: PEEK group recorded higher gap mean values (49.88±7.97um) than zirconia (18.39±3.1um). This was significantly (p < 0.05) as confirmed by Mann-Whitney test, but all measurements were clinically acceptable. And Thermo-mechanical cycling had no effect of on both groups. Conclusion: PEEK veneered with composite can be used intra orally for single crown restorations.

One Year Clinical Evaluation of Milled BioHPP Polyetheretherketone (PEEK)-Based versus Metal Ceramic Single Crowns (Randomized Controlled Clinical Trial)

“…Veneering of BioHPP PEEK copings started with application of dual-hardening combo.lign opaque as a first layer (wash opaquer) followed by crea.lign opaque on the BioHPP coping. They were polymerized for 180 seconds [14].…”

“…lign polishing Kit. They ensure a perfect finish and surfaces with high plaque resistance and shade stability [14] (Figure 3a).…”

Marginal Accuracy and Fracture Resistance of Posterior Crowns Fabricated from CAD/CAM PEEK Cores Veneered with HIPC or Nanohybrid Conventional Composite

“…132420) before pressing them on the cores utilizing a device delivering a uniform load of 5 kg (49 N) for 10 minutes. 12 Then, 180 seconds polymerization was performed at 220 mW/cm 2 (brelux Power Unit; bredent Senden, Germany). Each crown was then polished (Opal L, Renfert GmbH, Hilzingen, Germany; Lot No.…”

Comparative evaluation of internal fit and marginal gap of endocrowns using lithium disilicate and polyether ether ketone materials - an in vitro study

“…The values are less than those observed by Shin et al, Who reported internal discrepancies for CAD-CAM endocrowns of 200–300 μm [ 43 ]. This difference could be attributed to the fact that the internal fit of endocrowns is influenced by the cavity depth, restoration material and processing techniques [ 44 ].…”