RESUMEN
OBJECTIVE: To investigate of effects of using phase-contrast video technique on education in oral hygiene training. This one blind, parallel randomized controlled trial was conducted in a tertiary clinic. Fifty-three patients who presented to the orthodontics department aged 12-20 years were divided into two groups randomly by computer-generated assigned codes to receive oral hygiene education. The participants were blinded to type of education method. Before orthodontic therapy, the control group was trained only by the conventional method, while the test group was trained by phase-contrast video microscopy method in addition to conventional method. Some images and videos of moving microorganisms in dental plaque were shown to the patients in test group on a computer monitor. SUBJECTS AND METHODS: The bacterial count, plaque index, and gingival index scores were compared. Measurements were obtained in baseline and follow-ups which were repeated with 1-month intervals after the training. RESULTS: The plaque index scores (1.05 ± 0.1 vs. 1.43 ± 0.2; P < 0.001) and gingival index scores (0.90 ± 0.1 vs. 1.14 ± 0.2; P < 0.001) in test group was statistically lower than those in control group at the end of the study. The gingival index scores reduced by 39% in test group vs. 14% in control group. The number of bacteria significantly decreased in the group trained with phase-contrast video microscope technique (8,059,133 ± 3016 vs. 10,830,600 ± 4919; 0.018). CONCLUSIONS: The training with phase-contrast microscopy has a more positive effect than the traditional method in oral hygiene education.