RESUMO
The infectious nature of severe early-childhood caries[S-ECC] points to the possible participation of immunologic host responses including neutrophils and their antimicrobial products. The aim of this study was to determine the neutrophil apoptosis, alpha-defensins [HNP1-3] and calprotectin levels in the saliva of preschool children and the association with S-ECC. Oral examinations were performed on 87 children aged 3-5 years and non stimulated whole saliva samples were collected. Thirty of these subjects were considered S-ECC children, 30 with moderate caries [MC] and 27 were caries free [CF]. to detect apoptosis, cell staining was done with Annexin-V-Fluos and propidium iodide, and they were analyzed by fluorescent microscopy. The concentration of alpha-defensins and calprotectin were assessed using ELISA. There were no statistical differences between groups considering the HNP1-3 or calprotectin salivary levels[p=0.06 and p=0.23, respectively]. The HNP1-3 and calprotectin levels were negatively correlated and the correlation was significant in MC group [p=0.03]. Lower levels of apoptotic neutrophils were obtained from CF subjects as compared with S-ECC children [p=0.03]. Our findings establish that apoptotic mechanisms could be implicated in the immunity responses associated with S-ECC. We cannot yet determine if the level of salivary alpha-defensins or calprotectin is predictive of S-ECC