RESUMO
Objective:To assess root canal morphological results and cleaning capacity in deciduous teeth instrumented with a reciprocating system.Material and Methods:15 deciduous molars and a total of 24 canals were selected for the study. Nine teeth(13 canals) were selected at random for microbiological analysis and 6 teeth (11 canals) were used for tomographic analysis of morphology. The roots used for the microbiological assessment were contaminated with standard strains of Enterococcus faecalis. All roots were instrumented using the WaveOne System with a Small (21:06) 21mm file and an X-Smart plus motor. Tomography was conducted with an I-CAT machine before and after instrumentation with the objective of analyzing the WaveOne System's shaping capacity. Statistics: Biostat 4.0 software was used to analyze results. The microbiological results (log10) and tomographic results (pixels) were analyzed using descriptive statistics and the Wilcoxon test.Results:There was a significant reduction in Enterococcus faecalis colony-forming units after instrumentation of the root canal systems of deciduous molars using the WaveOne system (p=0.0033) and significant enlargement of the root canal systems was observed after instrumentation (p=0.047), while morphology was maintained. Conclusion:The WaveOne System, using the Small file was effective for disinfection of the root canal systems of deciduous molars