Introduction:

This investigation evaluated the effect of fiber optic cable as inserts on the microleakage of class II composite restorations with gingival margins on root surfaces.

Methods:

24 maxillary 1^st premolar freshly extracted for orthdontic reasons were   & mounted in acrylic bases. Class II slots cavities were prepared on both proximal sides ( 3 mm wide, 1.5 mm deep ) with gingival margins on the root surface & then divided into 4 groups. Group I   & II – 5^th generation bonding agent ( Primer & bond NT , Densply) with & without fiber optic inserts respectively. Group III & IV – self etching adhesive agents ( clearfil SE bond, Kuraray ) with & without fiber optic inserts respectively. Z 350 (3M), posterior composite resin was restored incrementally & cured  with LED light ( smarlite dentsply). The teeth were then stored in 37 deg c distilled water for 2 weeks & thermocycled  for 3000 cycles (5 deg c & 55deg c  ). The tooth surfaces were sealed with nail polish except   at the restoration margin & immersed in 0.5% methylene blue  for 5 hrs. The dye penetration was assessed with the help of stereomicroscope at 80x magnification.

Results:

In Group I & III , microleakage scores were less when fiber optic inserts were used. Group III & IV specimen showed lesser microleakage in comparison with group I & II.

Conclusion:

Microleakage  was significantly less ( p< 0.05 ) when fiber optic inserts were used irrespective of bonding agents.