‌Comparison of microleakage in different methods of restoration ‌in posterior Clv cavities

  ‌Comparison of microleakage in different methods of restoration ‌in posterior Clv cavities     - Dr. N. Mohammadi* Dr. R. Khezrian**   *- Assistant professor of Operative Dentistry Dept. Faculty of Dentistry Tabriz University of Medical Sciences.   ** - Dentist.     Background and aim: Despite improvements in the properties of composites, glass ionomers and other tooth colored materials, a number of problems still exist in their clinical application including: post-operative sensitivity, microleakage, technigue sensitivity and color change. Different methods have been already presented to recuce microleakage. The aim of this study was to compare the microleakage of different restoration methods in posterior ClV cavities.   Materials and Methods: On the buccal surfaces of 90extracted human teeth, due to orthodontic treatment, periodotal problem or impaction, ClV cavities with gingival margin on CEJ were prepared. The samples were randomly divided into5 groups and restored as follows: A: Copalait varnish (Harvard) and amalgam (Cinalux) B: Dentin bonding agent (Exite) and amalgam (Cinalux) C: Dentin bonding agent (Exite) and light cure composite resin (Tetric ceram) D: Resin modified glass ionomer (Fuji II LC) and dentin bonding agent (Exite) and light cure composite resin (Tetric ceram) E: Dentin bonding agent (Exite) and flowable composite (Tetric flow) and light cure composite resin Tetric ceram)) Restorations were polished, thermocycled in 1600 cycles and immersed in 0.5% basic fushin. Samples1 were then sectioned and studied under a stereomicroscope to evaluate bye penetration. Data were subjected to Kruskal-Wallis test.   Results: All groups showed some degrees of microleakage. According to Kruskal-Wallis statistical . analysis, differences between groups were significant (P=0.00000<0.05). Group C showed the maximum and group D Showed the minimum microleakage. Mann-Whitney analysis was used to compare pairs of groups. Results significant differences between groups as (AD), (C>D), (DConclusion: Proper characteristics of glass-ionomer such as its tendency for dentin bonding may be a factor to reduce microleakage in cervical restorations. It is suggested to use glass-ionsmer under composite restorations in cases that esthetics and secondary caries prevention are important. In cases tath esthetics is not important and economic factor plays a role and the patient is not susceptible to recurrent caries, amalgam is ercommended. Key Words : Microleakage - Amalgam - Composite resin - Glass ionomer - Dentin bonding agent.   ‌