Estimation Of Self-Etch Adhesive System And Resin Cement Shear Bond Strength To Root Dentine With And Without Prior Etching - Pull-Out Test And Sem Analysis

Background. De-bonding is still considered to be the most common cause of failure concerning fiber posts. The proper application of adhesive is, therefore, crucial to improve the bond strength. Objectives. This study evaluated whether the additional etching before the application of cross-generation self-etch adhesive and resin cement can increase the shear bond strength between the root dentine and fiber post's surface.Material and Methods. Sixteen human one-canal teeth that had been extracted due to periodontal and orthodontic reasons were carefully selected for this study. They were divided into two groups of eight. Preparation of the specimens in both groups was equal except for the cementation procedure. The teeth were sectioned at the cementoenamel junction. The post space was prepared to a depth of 8 mm and a diameter of 1.5 mm with a special machine ensuring the repeatability of post spaces' shape. Posts were cemented using self-etch adhesive; in one group the root dentine was previously etched and the second group was without pretreatment. Posts were cemented with the use of metal rings. Then specimens were embedded in acrylic resin blocks. They were subjected to pull-out test using a Universal Testing Machine specially adapted to maintain the parallelism - regimen. Finally, the posts' surface was evaluated in SEM observation. Obtained results were statistically analyzed.Results. The mean shear bond strength values for group with prior etching of dentine were significantly lower (8.22 MPa) than for the group without prior etching (11.25 MPa). These findings were supported by SEM observations, revealing that in the group with prior etching the resin-dentin-interface failure surpassed the resin-postinterface component.Conclusions. Obtained results indicate that the self - etch adhesives' bond strength to root dentine is decreased in case of prior etching