The study compared the attitudes and behavior of 4th-year dental students regarding infection control rules in 1995 and 2005. Self-administrated questionnaires were applied to 592 students at 5 different dental schools in 1995 (n=350) and in 2005 (n=242). The chi-square and Fisher's exact tests were used for statistical analysis of data. Significance level was set at p<0.05. The response rate was 90.3% in 1995 and 81.0% in 2005. There was no improvement in the use of rubber gloves (p=0.316), face masks (p=0.572) or gowns (p=0.862) between 1995 and 2005. There was a lesser frequency of the use of protective eyewear in 2005 (p<0.001). No student used the individual protection equipment correctly. There was a decrease in the sterilization of burs in 2005 when compared to 1995 (p<0.001). No student could describe the correct use of the autoclave. Disinfection and use of a dental chair barrier were done correctly by a minority of students in 1995 (2.8%) and 2005 (6.1%) (p=0.069). Most students correctly discarded perforating/cutting instruments in both years (p=0.749). The attitudes and behavior of dental students concerning infection control are worrisome. There was no improvement and, for some parameters, there was a worsening in the procedures over the time period evaluated.