The purpose of this study was to estimate the relation between techniques used for microleakage from dye penetration and for marginal adaptation from SEM evaluation of the restoration.

Using high speed #330 bur, class V cavities (4 × 3 × 1.5 mm around CEJ) were prepared on the buccal surface of 20 extracted human molars. Six dimples as reference points for SEM and dye penetration evaluation were made with 1/2 round bur. Cavity was bulk filled with microhybrid composite resin (Esthet X) and all-in-one adhesive (Xeno III). Teeth were stored in saline solution for one day, after then, they were finished and polished using Sof-Lex system.

Fifty percent silver nitrate dye solution was used for the evaluation of microleakage and resin replica was used for marginal adaptation. All of these were done after 1000 times thermocycling between 5 and 55℃.

Vertical sections were made through three dimples of restoration to obtain samples for the evaluation of dye penetration and inner marginal adaptation. Outer adaptational estimation was done with an intact restoration before sectioning. Dye penetration was determined in three degrees and percentage of outer and inner leaky margin was estimated from SEM image.

The data were analysed statistically: Spearman's rho test were used to check relationships between two methods.

The result were as follows:

There were significant relationships between degree of dye penetration and inner and outer marginal adaptations each (p < 0.01).

Within the results of this study, relationship between the percentage of marginal adaptation and microleakage shows significant relationship. However, inner and outer marginal adaptation did not show any significant relationship mutually.