الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 135 |  |  |
| | | from | 135 | | |
Abstract
This study aimed to evaluate nanoleakage in self-adhering flowable composite, total etch adhesive system, self-etch adhesive system and glass ionomer based restorative material in Class V restorations in primary teeth dentin. Sixty sound primary molars were included in this study. Standardized Class V cavities were prepared on the labial surface 1 mm above the CEJ. Teeth were randomly distributed into the four groups 15 in each group then each was restored according to manufacturers’ instructions. Each group was subjected to thermocycling between 5°C and 55°C for 500 cycle then sectioned buccolingually into 2 halves through the center of the restoration.
Nanoleakage test was performed by using 50% wt ammoniacal silver nitrate. Specimens were dehydrated and exposed to EDX. Elemental distribution of silver content in percent weight was determined in the form of peaks on a graph with their corresponding readings.
It was found that there is a statistically significant difference in the mean percent of silver penetration between the four groups. Scanning Electron Microscope images were captured at 25kv and x2000 magnification showed presence of silver particles and x5000 images were taken to note special findings. group 1 showed the absence of a distinct hybrid layer. Massive line-like homogeneous silver deposits were apparent through the whole adhesive layer, even in dentin tubules. There were also microgaps filled with silver deposits. group 2 showed a distinct hybrid layer of variable thickness and presence of resin tags penetrating dentinal tubules, presence of discrete areas of silver uptake along the interface between dentin and the resin and extending within the resin tags. A small amount of silver particles were also seen on higher magnification embedded in the resin tags. group 3 showed distinct uniform thin hybrid layer with absence of visible silver deposits. group 4 showed absence of a distinct hybrid layer and presence of abundant silver deposits.
Each specimen was given a score from 0-3 according to extent of nanoleakage judged by extent of metallic silver particles in the SEM images observed in the evaluated area along the resin-dentin interface. There was a strong, positive correlation between penetration of the silver and leakage, which was statistically significant.
Based on the results of the present study, self-etching adhesive system exhibited the least nanoleakage in class V cavities in primary teeth dentin