Detection and function of lipopolysaccharide and its purified lipid A after treatment with auxiliary chemical substances and calcium hydroxide dressings used in root canal treatment

Abstract

5.25% NaOCl and Ca(OH) dressings from 24 h onwards were able to induce both, loss of lipid A peaks and no detection of LPS bands, rendering a diminished immunostimulatory activity through TLR4.

Endotoxin levels after chemomechanical preparation of root canals with sodium hypochlorite or chlorhexidine: a systematic review of clinical trials and meta‐analysis

“…Nevertheless, a recent in vitro study showed that amongst 1%, 2.5% and 5.25% NaOCl, only the last one was able to induce loss of lipid A peaks and LPS bands detection (Marinho et al . ).…”

Etiologic role of root canal infection in apical periodontitis and its relationship with clinical symptomatology

“…Lipid A is the bioactive component of LPS responsible for most of the host's immune response. 51,52,53,54 LTAs are present on the surface of gram-positive cells, such as Enterococcus faecalis, and have adhesive properties, as they adsorb to hydroxyapatite, binding through its lipid portion. They stimulate leukocytes, monocytes, and macrophages to release inflammatory mediators.…”

“…In endodontic therapy, hydroxyl ions present in the calcium hydroxide paste can hydrolyze LPS, degrading lipid A and neutralizing its residual effect after cell lysis. 54,114 LPS is known to be the most toxic constituent of bacterial endotoxin, having no structural homologue among multicellular organisms. 115 In general, bacterial LPS are composed of three structural domains: lipid A, core, and repeating O-antigen.…”

“…32,64,136 The residual endotoxins found after CMP, if access to periradicular tissues is allowed, would modulate host immune responses by the expression of different cytokines and MMPs. 30,54 Moreover, it has been shown that an elevated inflammatory state caused by metabolic disorders can impact the clinical outcome of periapical lesions and interfere with wound healing after endodontic treatment. Immunoregulatory cytokines produced by various cell types, including immune cells and adipose tissue, play an important role in this interrelationship.…”

Comparison of two rotary systems in bacteria/lps removal from endodontic infections: randomized clinical trial

“…39 Other studies confirm the ability of calcium hydroxidebased medication to eliminate endotoxins at different time periods of action. 40…”