Reyes A. Effectiveness of using children's toothbrush with multilevel filaments associated with anteroposterior toothbrushing in removing dental plaque from occlusal surfasse of erupting permanente molars. [dissertação]. São Paulo: Universidade de São Paulo, Faculdade de Odontologia; 2011.The present study aimed 1) to evaluate the effectiveness of anteroposterior toothbrushing using a children`s toothbrush with multilevel filaments vs. crosstoothbrushing technique using straight bristles in short and long-term analysis;2) to compare different methods assessing dental plaque in occlusal surfaces and 3) to verify the association between clinical parameters and the removal of biofilm on the occlusal surfaces of erupting permanent molars. Different outcomes concerning dental plaque were chosen: presence of visible plaque, presence of mature plaque, area of disclosed plaque and plaque fluorescence measured by a quantitative light fluorescence device (QLF). Two calibrated and blinded examiners performed the examinations using indices and only one assessed the biofilm using the QLF. Another examiner was responsible for explaining the techniques and evaluating the degree of deterioration of the toothbrushes. Thirty-three children aged 5-7 years (mean=6.23, SD=0.56), who attended the screening of the discipline of Pediatric Dentistry FOUSP, were select. In those children 92 erupting molars are included. These children were randomly assigned into two groups according to the toothbrushing technique Teeth were evaluated by the methods at baseline and after 15 days, 1 month and 3 month. Some clinical parameters were also analyzed regarding their association with plaque reduction. Multilevel analysis were performed to determine which technique is the most effective in removing plaque on occlusal surfaces of erupting permanent molars. Reproducibility and correlation of methods for plaque measuring were also tested. After 15 days, no difference was observed between groups. However, after 1 month of following-up, higher reduction in mature and visible plaque were found using the toothbrushes with multilevel filaments. Visual indexes for plaque evaluation presented poor correlation between themselves and the plaque fluorescence measured by QLF did not show correlation with visual them. Different clinical parameters were associated with biofilm removal by toothbrusing techniques. In conclusion, in a long-term analysis, the toothbrishing with multilevel filaments is able to disorganize the plaque on occlusal surfasse of erupting molares more efficiently and the methods for plaque assessement evaluate different parameters related to plaque. Finally, the reduction in mature plaque and in visible plaque are differently associated with clinical parameters, suggesting they measure slight different aspects related to de dental plaque on occlusal surface of erupting teeth.