Effects of dentin bonding agents (DBA) coronal leakage in root canal therapy (In – Vitro)

 Dr. MR. Sharifian* - Dr. E. Kazemifar**

 *- Assistant Professor of Endodontics Dept. - Faculty of Dentistry – Tehran University of Medical Sciences.

**- Dentist.

Background and Aim: Coronal sealing plays an important role in the prevention of root canal system reinfection and the access of irritants to periradicular tissues. The aim of this experimental (in – vitro) study was to evaluate the effects of dentin bonding agents in the reduction of coronal microleakage and improvement of root canal seal.

 Materials and Methods: In this experimental study, twenty four extracted straight single rooted human teeth were randomly divided into two groups of ten. In the first group, after DBA application, root canals were filled with gutta percha and AH26 using lateral condensation technique. In the second group, root canals were only filled with gutta – percha and AH26. Two groups were also considered, as positive and negative controls. In positive control group, the root canals were filled with gutta – percha only. Then all teeth surfaces except the cut coronal surface were covered with two layers of nail varnish. In negative control group all surfaces were covered with two layers of nail varnish. The specimens were immersed in methylen blue dye (PH=7) for 48 hours. After rinsing the teeth and removal of nail varnish, the specimens were divided into buccal and lingual halves using diamond disk. The amount of linear penetration of dye was measured with stereomicroscope. Data were subjected to t – student test.

 Results: The mean of dye penetration was 3.2±1.217 mm in the first group (DBA + gutta percha + AH26) and in the second group (gutta percha + AH26) was 6.1 mm. The difference between two groups was statistically significant (P<0.001). In positive control group dye penetrated in the entire length of canal, however in the negative control group dye penetration was not observed.

 Conclusion: The use of D.B.A with gutta percha and AH26 using lateral condensation technique is effective in the reduction if coronal leakage. Key words: Leakage – Dentin bonding agent (D.B.A) – Root canal.