Addition of cetyl pyridinium chloride to histological demineralizing agents to improve the demonstrability of gram-positive bacteria.
It has previously been shown experimentally using S. faecalis that the relative number of Gram-positive bacteria is reduced by demineralizing agents. To achieve better bacterial preservation after demineralization, cetyl pyridinium chloride (CPC) and neutral formaldehyde solution (NF) were added, separately and in combination, to formic acid and EDTA. The number of S. faecalis organisms in suspension was determined using a haemocytometer, and the percentage of Gram-positive bacteria was ascertained from smears. Both CPC and NF accomplished better bacterial preservation; when both substances were added together preservation was improved still further. The best results were achieved when CPC and NF were added to EDTA. If these findings could be extrapolated to tissue sections, and if it were intended to demonstrate Gram-positive bacteria, 10 per cent EDTA to which 0.5 per cent CPC and 4 per cent NF had been added would be recommended for demineralization.
Van Mullem
P J
PJ
Department of Oral Histology, Dental School, University of Nijmegen, The Netherlands.
Wijnbergen
M
M
D001431:Bacteriological Techniques; D002594:Cetylpyridinium / Q000494:pharmacology*; D003648:Decalcification Technique; D004492:Edetic Acid; D013293:Enterococcus faecalis / Q000187:drug effects / Q000302:isolation & purification; D005561:Formates; D006094:Gram-Positive Bacteria / Q000187:drug effects / Q000302:isolation & purification*; D006652:Histological Techniques; D013194:Staining and Labeling / Q000379:methods
D005561:Formates; C030544:formic acid; D004492:Edetic Acid; D002594:Cetylpyridinium