Effect of Teeth Contamination on The Retention and Microleakage of Stainless Steel Crowns in Primary Molars.

Aim: determine the effect of teeth contamination on the retention and microleakage of stainless steel crowns in primary molars cemented either with; resin modified glass ionomer cement or self-adhesive resin luting cement. Methodology: One hundred and twenty extracted primary maxillary and mandibular molars were collected and stored in tap water at 37°C till its use for the study. The roots of each tooth were embedded in self-cure acrylic blocks. Standard SSC preparations were performed for all molars. After fitting SSCs, the sample was divided into non-contaminated group (n=40): group A; 40 teeth, and contaminated groups (n=80): group B saliva contamination and group C saliva and blood contamination (40 teeth each). Then each group was subdivided into two sub-groups; 20 teeth each according to the type of the luting cement, which then subdivided into 10 teeth for retention test and 10 teeth for microleakage test. For groups B&C, teeth enamel was contaminated immediately before cementation process. Luting cements used in this study were resin modified glass ionomer (FujiCEMR 2) or self-adhesive lutting cement (MulitilinkR Speed). After crowns cementation retention test was measured for the allocated groups using instron universal testing machine, while microleakage test was evaluated with the digital method for the other groups.  Results:  Compared to the experimental groups, the control group (non-contaminated; group A) showed the highest retention value and the least microleakage. Self adhesive resin luting cement significantly had higher retention and less microleakage degree than resin modified glass ionomer cement with a significant difference (p < 0.001). Under saliva (group B) and saliva and  blood (group c) contaminations, the mean retention value of self adhesive resin was higher when compared to retention of RMGIC with a significant difference in saliva group (p < 0.023), and in saliva and blood group (p < 0.18). Also less microleakage was recorded with both types of cement in saliva contamination when compared with saliva and blood contamination with a significant difference (p < 0.001). The highest degree of microleakage (3473.00±486.21) was observed with RMGIC in group C. Conclusion: The self adhesive luting cement had a significantly higher retention, and lesser microleakage than RMGIC in all conditions of this study. Both materials showed a significant increase in the retention value and lesser degree of microleakage when contaminated with only saliva than with saliva and blood contamination.