Evaluation of Zirconia Post and Zirconia Coated FRC Post

Objectives: One of the problems in preparation of root canal treated teeth is debonding of post from root dentin; which correlates to post type. If measures are not taken to avoid this problem, mortal outcomes will appear during treatment. One of the new post that is used nowadays is the zirconia coated FRC posts, that are the next generation of aesthetic posts, ice light features 70% fill of zirconia enrinched, parallel glass fiber for exceptional strength. Its flexibility is close to dentine, so stress is distributed. The aim of this study was the evaluation of post types (zirconia post and zirconia coated FRC post.

Methods: The research method was experimental. 20 extracted human premolar teeth with 14 mm root length were selected. After post space preparation, the teeth were randomly divided into two groups (20 mm length and 1.4 mm diameter posts). Group 1: zirconia coated FRC post (Danville), Group 2: zirconia post (Ivoclar vivadent). All posts were cemented with dual-cure resin cement (Kuraray Panavia). All samples were mounted in acrylic cylinders. Samples were divided to 3 mm length parts. Make stress in apical to coronal direction with 0.8 mm diameter rod and inscripted pressure percentage. The push-out test was done by means of universal testing machine (Instron 5500R) with 1 mm/min speed. Data were analyzed through t-test.

Results: Retention average for the zirconia coated FRC post in coronal are as follows in Mpa: 79.22±12.93, middle:71.76±16.79, apical: 48.64±13.85 for the zirconia post in coronal: 131.80±32.52, middle:93.17±5.27, apical: 40.57±6.51.

Conclusions: Zirconia post provided significantly increased post retention compared with the zirconia coated FRC post. The retention of both post type reduced from coronal to apical.