Bond strengths to endodontically-treated teeth

Purpose: To evaluate the bond strengths of three different types of resin bonding systems to teeth prepared for endodontic treatment. Materials and Methods: Access cavity preparation and removal of pulpal tissue were performed in bovine incisors. The root canals were chemically irrigated with saline (control), 5% sodium hypochlorite, 3% hydrogen peroxide, or combinations of both for 60 s. After storage in water for 1 d, the dentin surface was ground to a flat surface with 600-grit SiC under water. The area for bonding was demarcated with a vinyl tape (4 mm-in-diameter hole), and bonded using either Clearfil Liner Bond II, Single Bond, or Superbond C&B. After storage in 37°C water for 1 d, tensile bond strengths were measured using a universal testing machine at a crosshead speed of 2 mm/min. Ten teeth were tested for each group. Results: One-way ANOVA and Fisher's PLSD test revealed that Single Bond and Superbond C&B had a statistically lower (P < 0.05) bond strengths in the chemical irrigation groups compared with the control group.link_to_subscribed_fulltex

Biocompatibility of a Flowable Composite Bonded with a Self-etching Adhesive Compared with a Glass Ionomer Cement and a High Copper Amalgam

This study evaluated the pulpal response and in-vivo microleakage of a flowable composite bonded with a self-etching adhesive and compared the results with a glass ionomer cement and amalgam. Cervical cavities were prepared in monkey teeth. The teeth were randomly divided into three groups. A self-etching primer system (Imperva FluoroBond, Shofu) was applied to the teeth in one of the experimental groups, and the cavities were filled with a flowable composite (SI-BF-2001-LF, Shofu). In the other groups, a glass ionomer cement (Fuji II, GC) or amalgam (Dispersalloy, Johnson & Johnson) filled the cavity. The teeth were then extracted after 3, 30 and 90 days, fixed in 10% buffered formalin solution and prepared according to routine histological techniques. Five micrometer sections were stained with hematoxylin and eosin or Brown and Brenn gram stain for bacterial observation. No serious inflammatory reaction of the pulp, such as necrosis or abscess formation, was observed in any of the experimental groups. Slight inflammatory cell infiltration was the main initial reaction, while deposition of reparative dentin was the major long-term reaction in all groups. No bacterial penetration along the cavity walls was detected in the flowable composite or glass ionomer cement except for one case at 30 days in the glass ionomer cement. The flowable composite bonded with self-etching adhesive showed an acceptable biological compatibility to monkey pulp. The in vivo sealing ability of the flowable composite in combination with the self-etching adhesive was considered comparable to glass ionomer cement. Amalgam restorations without adhesive liners showed slight bacterial penetration along the cavity wall.link_to_subscribed_fulltex