Effect of surgically implanted root-end filling materials on the structure of draining lymph nodes of male albino rats: histological and immunohistochemical study

ABSTRACT

The success of endodontic surgery depends on the histocompatibility of the root-end filling material. Applications of nanotechnology improve their performance. Aim of the work was to compare the effect of a mineral trioxide aggregate [MTA]and a bioceramic nanoparticulate bioaggregate [BNB] on the histological structure of draining axillary lymph nodes of adult male albino rats after their surgical implantation into the skin. Forty adult male albino rats were divided into control and experimental groups.The latter was subdivided into MTA and BNB surgically implanted subgroups. After 7 days, the rats were sacrificed. Paraffin sections from both the proximal part of the dorsal skin and draining axillary lymph nodes were processed for H and E staining.Lymph node sections were further subjected to silver reticulin, Verhoeff's Van Gieson stains as well as kappa light chains. Quantitative assessments and statistical analysis of the results were carried out. There was an increase in mononuclear inflammatory cells infiltrating the skin in the MTA subgroup. Lymph nodes of the MTA subgroup showed a marked decrease in the lymphocyte content of lymphatic nodules, wide lymph sinuses, multinucleate giant cells, and many macrophages. In the BNB-treated subgroup, lymphatic nodules had wide corona and small germinal centers. Reticular and collagen fibers were increased in the MTA subgroup. Kappa light chains' immunoreactions were strong positive in MTA and mild positive in BNB subgroups. A highly significant increase in the mean area% of all fibers and kappa light chain immunoexpression of lymph nodes of the MTA subgroup were observed. MTA had less biocompatibility. BNB showed limited signs of acute inflammation. BNB is an up-to-date alternative to the currently used root-end filling materials. The chronic effects caused by BNB may require further study