The oral cavity is a reservoir for Helicobacter pylori, and occupations that involve close contact with it, like Dentistry, could entail a higher risk of colonization. The aim of this study was to evaluate if the length of stay at the School of Dentistry of the University of Granada could influence colonization by H. pylori, and to furthermore correlate colonization by H. pylori, with the state of oral health and oral hygiene habits. The study groups were: Group 1, 35 students of Odontology in their first year of studies; Group 2, the same 35 students when they were in their fifth academic year; Group 3, 35 students from University study programs unrelated with Health and of the same age as the group 2 students. All underwent H. pylori, colonization determinations by means of the urea breath test (UBT), stool antigen test and a serological test. Also studied were the variables plaque index, gingival index and the number of times teeth were brushed per day. The Student t test was used for comparisons among the three studied groups. The Chi-squared test and Pearson correlation coefficient were used to determine any connection between colonization by H. pylori, and the variables studied. Comparisons between groups 1 and 2 and between groups 2 and 3 showed significant differences regarding colonization by H. pylori, plaque index, gingival bleeding index and tooth brushing. A positive correlation was found between being colonized by H. pylori, and having a gingival index higher than 10% and tooth brushing once a day or less, in all the studied groups. Colonization by H. pylori, among Dentistry students at the University of Granada decreased over a four-year time period at the University. Factors related with better oral health, such as a lower gingival index and more frequent tooth brushings, would explain these results.