Sulfate-Reducing Bacteria: Biofilm Formation and Corrosive Activity in Endodontic Files

Table 3

Measurement of pH at different cell culture times and cell viability of replicas from the different culture times.

		Postgate C culture medium	Modified Postgate E culture medium
Time		Desulfovibrio desulfuricans (oral)	Desulfovibrio desulfuricans (environmental)		Desulfovibrio fairfieldensis (association)
		UEF-1	UEF-3	UEF-4	UEF-2
pH/cell growth	Culture 445 days	pH 7/reduction	pH 7/positive	pH 7/positive	pH 7/positive
	Cultivation 7 days (maintenance of 445-day biofilm)	—	—	7/positive	—
	Cultivation 14 days (maintenance of 445-day biofilm)	pH 7/reduction	—	—	pH 7/positive
Replica	Replica of original culture (445 days)	Negative	Negative	Positive	Negative
	Replica of samples of reimmersion culture	Negative	—	Positive	Positive