The chitinolytic microorganisms, isolates 18 and 19, were selected from soil samples around a region of frozen shrimp factory in Chonburi province. These isolates had high potential for using chitin as a carbon source from the chitin broth, which was composed of 1.0% chitin, 1.0% NH4NO3 and 3.0% yeast extract. The cultures were grown at 200 rpm, 30∞C and initial pH of 6.8-7.0 for 7 days. It was...

Our objective is to analyze the constitution and drug resistance of pathogenic microorganisms in infected root canals. 69 patients with chronic periapical periodontitis were selected, the tooth root canals of which were collected. There were 15 cases (group A) with root canal infection after root canal treatment failure, 18 cases (group B) with root canal infection after dental crown restoratio...