The Effect of Blood Contamination on the Retrograde Sealing Ability of Biodentine: A Micro-CT Analysis

Abstract

AIMS To evaluate the sealing ability of Biodentine in its use as a root end filling material. To evaluate how the sealing ability of Biodentine would be affected by contamination with blood. To evaluate the use of micro-CT and silver nitrate as a method to examine sealing ability and the microleakage of different dental materials. MATERIALS AND METHODS: Thirty single rooted teeth were selected as sample teeth. Sample teeth were prepared and obturated using gutta-percha and Ah Plus sealer. The samples were coated with nail polish, resected 3mm apically with a 0 degree bevel angle. Samples were labeled, each was apically prepared 3mm using an ultrasonic tip. Samples were assigned at random to either the uncontaminated sample group or the blood contaminated sample group. All the samples were filled using Biodentine following manufacturer’s instructions. For the blood contaminated sample, one drop of blood was placed into each root end preparation. The blood was left in place for 1 minute and then air dried, leaving blood on walls of the retropreparation. The blood contaminated samples were filled with Biodentine. All of the prepared sample groups, were placed in PBS for one week to allow for proper setting of the Biodentine material. A 25% w/w solution of silver nitrate solution was used to soak the samples overnight and allow penetration into the samples. Samples were scanned using a micro-CT unit. For each component (silver nitrate, Biodentine, voids), an object volume was calculated using the CT-Analyzer software. An overall volume of the root end preparation was calculated to compare each component in order to get a percentage. The depth of the root end preparation and depth of silver nitrate penetration were calculated according to the voxel size and the number of slices included for each sample. The data were entered into an Excel spreadsheet and statistical analysis was completed using GraphPad Prism Version 8.1.2 statistical software. RESULTS: A significant difference was found between the two sample groups in the percentage of silver nitrate volume compared to the overall retropreparation volume, with the blood contaminated group showing less penetration of silver nitrate. A significant difference was found in the void percentage of the total volume between the two groups, with the blood contamination group showing more voids in the root end filling material. No statistical difference was noted between the depth of silver nitrate penetration between the two groups. CONCLUSIONS: Blood contamination does not affect the sealing ability of Biodentine, when it is used as a root end filling material. The presence of blood in the root end preparation significantly increases the volume of voids present in the root end filling material. The combination of silver nitrate as a tracer and micro-CT to evaluate microleakage is a promising study design for future applications