The concentration of lipopolysaccharide on individual root surfaces at varying times following in vivo root planing.

Material with endotoxin activity has been detected in extracts prepared from pooled, periodontally involved teeth, and it has been shown that root planing in vivo reduces the level of such material. However, questions concerning the concentration of endotoxin on the diseased surfaces of individual teeth and questions concerning how rapidly individual root planed tooth surfaces retoxify in vivo have not been addressed previously. Citric acid extracts were prepared from individual, periodontally diseased teeth that had been extracted either from the oral cavity without prior root planing or at varying times up to 12 weeks following root planing. Using a chromogenic Limulus Amebocyte Lysate (LAL) assay, we were able to quantitate the amount of endotoxin associated with diseased root surfaces of individual teeth. We concluded that the extracted material contained endotoxin since it activated LAL and since the LAL-activation was heat-stable, acid-stable and neutralizeable by polymyxin B. The levels of endotoxin found on the root surfaces of these individual, periodontally involved teeth at varying times following in vivo root planing support the following conclusions: the concentration of endotoxin present on diseased root surfaces is markedly reduced, but not eliminated, by in vivo root planing, significant retoxification of root planed surfaces occurs within a relatively short time period after root planing and biological responses to such toxification conceivably may lead to subsequent phases having reduced levels of endotoxin.