Effect of relining, cement type, and thermocycling on push-out bond strength of fiber reinforced posts

Effect of intra-radicular rehabilitation techniques on push-out bond strength of fiber-reinforced posts in extremely flared canals

“…9 In addition, as expected, Gr1 recorded higher bond strength values than Gr2 because of the presence of resin cement layer which enhanced the chemical bond between the light-transmitting fiber post and the bulk-fill composite resin. 10 In groups (3&4), the bond strength values at flowable composite/root dentin interface were lower than that in groups (1&2) where bulk-fill packable composite was used. Although, Any-Com Flow showed better mechanical properties due to the presence of zirconia nano-particle fillers, increasing the filler content potentially reduces reactive resin matrix, compromising adhesive bonding of resin composites to root dentin.…”

“…32 The cement/ root dentin interface is considered as the weakest link in post cementation, and the use of cement with proper mechanical properties is essential for adequate post retention. 10 Besides, depending only on the ability of light transmission via translucent post by using 'single curing method' seemed to be insufficient for conversion degree of resin cement at the interface. 33 However, the difference between Gr5 and Gr6 was insignificant because the bulkfill composite is more translucent, which allows more light to pass through the body of the material to enhance polymerization in deep locations.…”

“…Augmentation (or reinforcement) of intraradicular dentin and customization (or relining) of fiber post are two clinical options recommended to increase adaptation of prefabricated fiber reinforced posts to extremely flared canals. [8][9][10] The difference between both strategies is based on the number and type of interfacial surfaces that form the monoblock system. This study suggested different techniques used to strengthen structurally compromised and weakened roots, using the introduced innovative composite resin materials.…”

“…6,7 Therefore, the intra-radicular rehabilitations either by augmentation of intra-radicular dentin or customization of fiber post were suggested to adapt the root canal to the fiber post or to adapt the fiber post to the canal, respectively. 5,[8][9][10] The main goal of intra-radicular rehabilitation is to reinforce the remaining dentin thickness less than 2mm before post placement. In addition, to increase adaptation between a prefabricated post and flared canal that leads to better retention.…”

“…In addition, to increase adaptation between a prefabricated post and flared canal that leads to better retention. 10 The techniques suggested for intra-radicular rehabilitation based on achieving the monoblock effect through the following three principles: first; the selected post and core system used to restore flared canals should have Elastic Modulus similar to dentin, second; adhesive bonding of composite resin and\or resin cement to radicular dentin, third; composite resin can be used for intra-radicular rehabilitation as it absorbs and distributes forces in a more uniform manner and increases resistance to fracture, thus providing improved prognosis. 11 Moreover, the introduction of commercially available light-transmitting posts allows light polymerization by transillumination that effectively polymerizes the composite along the entire length of the intra-radicular preparation.…”