The perception of Periodontology learning environment was measured before and after curricular restructuring by the Dundee Ready Education Environment Measure (DREEM). Undergraduate students (2nd, 3rd, 4th years; n = 266) were divided into two main groups: former curriculum (n = 131) and current one (n = 131). Total DREEM score, its five dimensions, Periodontology grades and their weighted average were compared. Student’s t test and ANOVA were used for analysis (p < 0.05). There was a statistically significant difference between the second (teachers) and fifth (social relations) dimensions and between Periodontology grades and the weighted average in both curricula. For each year, higher scores in the second dimension, Periodontology grades and the weighted average were obtained for current curriculum. Both curricula presented a significant correlation between Periodontology grades and their weighted average. Total DREEM scores for 2nd, 3rd and 4th years of current curriculum presented no differences (p > 0.05). The implementation of a new curriculum had an important impact on the students’ positive perceptions, which reflected in their academic performance