Search

Composite cements are widely used in dentistry, due to their positive characteristics (bond strength, color, low solubility etc.). However, removal of the cement presents one of the drawbacks of their use, since incomplete removal might cause bacterial adhesion, gingival irritation and subsequent inflammation. The aim of this study was to investigate surface characteristics of the composite cements after different ways of excess removal, by means of profilometric and SEM analysis. Thirty leucite reinforced ceramic specimens were divided into three groups, based on the manner of excess cement removal: Group 1 (polished): excess was fully polymerized for 40 s, then removed; Group 2 (cleaned): excess was removed with a cotton roll, after which cement was fully polymerized for 40 s; Group 3 (pre-polymerized): excess was light cured for 5 s, after which cement excess was broken with an instrument and then fully polymerized for 40 s. Surface roughness was measured using a surface profilometer. Subsequently, specimens were inspected by a scanning electron microscope. The data were statistically analyzed. The examination of variants of average values proved the statistically significant difference in the height of average values per group, p

The aim of this study was to compare in vitro the characteristics of different types of luting cements (zinc phosphate, glass-ionomer and resin based composite cement) using scanning electron microscopy (SEM) analysis and microleakage for the quality range of materials. Dental cements were mixed in accordance with the manufacturer's instructions and formed with posts in dental root canals of extracted teeth. The quality of cement was determined by SEM observation on horizontal sectioned roots with fixed posts according to specific pore and marginal gap diameter. The microleakage was measured on specimens immersed in Lofler (methylene blue) solution. The mean values of the maximal diameter of pores, marginal gaps and microleakage of conventional cements are remarkably larger in comparison with composite luting agents. In conclusion, the quality and efficiency of composite luting agents in comparison with conventional cements are more successful in protecting the interior of tooth from penetration of oral fluids, bacteria and bacterial toxins into unprotected dentine.