Occurrence of microorganisms at different levels of the pulp. Contribution to endodontic techniques.

Microorganisms were absent in the remaining pulp stumps of twenty teeth which had been exposed to caries and contaminated at the pulpal chamber level. We have demonstrated that microorganisms are not carried to the deepest areas of the pulp when the basic procedure is strict antisepsis applied to the living pulp stump. A sterile and living pulp stump wound contributes to an adequate biologic sealing of the apical foramen. Of all the isolated microorganisms, the alpha hemolytic Streptococcus was most frequently found in all examined cases, in pure or mixed cultures, demonstrating once again he prodominance of that type of microorganism when pulpal injury occurs.