Effect of Cavity Dimentions with the Same C-Factor on Micro Leakage of Composite Resin Cavities

Given the prevalence of microleakage in composites and their known complications and lack of reporting of the influence of cavity depth and diameter on the same c-factor on the microleakage of composite cavities, this study investigated the effect of microleakage on composite cavities in identical C Factors.

In this experimental study on 40 specimen (4 group of 10 each ) Cylindrical cavities with different volumes were prepared using diamond bur no. 006 in buccal surface of teeth (c-factor = 5). Height and width of cavities, respectively: Group I: Height and diameter 2 mm. groupII: height 2 and diameter 4 mm. Group III: height 4 and diameter 2 mm. Group IV: height and diameter 4 mm. All teeth were then restored with the same procedure. The specimens were then placed in a thermocyclic machine.The microleakage was  evaluated using 50% weight silver nitrate findings were statishtically evaluated with kruscallwallis test considering significant level of 0.05.

There was no significant difference between Gingival leakages in 4 groups (p = 0.163). There was a significant difference between 4 groups in occlusal leakage and groups 1 with 2, 2 with 3 and 2 with 4 revealed differences significantly.(P=0.019) Comparing gingival and occlusal microleakage between groups 1,3,4. :there was not significant difference. (P>0.05)
 Group 2, there was significant difference between occlusal and gingival microleakage at p = 0.004 and gingival leakage rate was significantly greater than occlusal leakage. (P<0.05)

There was no significant direct correlation between C- factor and microleakage, but it seems, microleakage was increased with increasing the cavity dimention.