The purpose of this study was to determine whether the precautionary measures used in the Faculty of Dentistry, University of Nuevo Leon, are adequate to prevent infection with Mycobacterium tuberculosis, taking as evidence two groups: one of 92 students of 2 °. Half have not seen patients and another group of 108 students in 9 th. and 10 °. Semesters that have served patients in different clinics of the institution. Research were conducted in two laboratory tests, the Mantoux test by inoculating 0.1 ml of PPD (purified protein derivative) to read 48 hours later, taking as positive for the one with induration of 10mm or more prior contact means with the bacillus and obtaining from them 5 mL of peripheral venous blood to perform the ELISA test for detection of latent TB blood test that analyzes the presence of IgM and IgG antibodies against extracellular proteins of Mycobacterium tuberculosis (Dr. C. Alma Yolanda Arce Mendoza). Among the groups studied, the 2 °. Semester (new entry) were found to have greater contact with M. tuberculosis than 9 °. and 10 °. Semesters when analyzing the results of the group F6, F7 and F8 where there are more students tested positive test, this equates to 29.3% and indicates infection is present. Since only two students from one hundred and eight total semesters analyzed above were positive for IgM, this equates to a rate of 1.8%. In conclusion, newly admitted students who tested positive to the tests, and had previous contact in your environment, and that means immune resistance to tuberculosis infection. Furthermore, the absence of a positive IgM test increased in the group of students from 9 th. and 10 °. Semesters, indicates that there is no danger of infection during their professional development.
