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Antibacterial effects of chemomechanical instrumentation and calcium hydroxide in primary teeth with pulp necrosis
Denise Lins de Sousa1, Rebecca Bastos Rocha Araújo de Sousa, Daniela Nunes Pinto
1Department of Dental Clinics, School of Pharmacy, Dentistry and Nursing, Federal University of Ceará, Fortaleza, Ceará, Brazil.
Purpose:
This study's purposes were to: evaluate the antibacterial effect of chemomechanical instrumentation and a calcium hydroxide-based dressing in primary teeth with pulp necrosis secondary to trauma; and detect the presence of Fusobacterium nucleatum and black-pigmented rods in the canals of these teeth.
Methods:
Microbiological sample collections (MSCs) were obtained: after coronal access to the canals of primary incisors (in 18 teeth; MSC 1); after chemomechanical instrumentation (in 10 teeth; MSC 2); and 72 hours after removal of intracanal medication (in 18 teeth; MSC 3). These samples were sent for microbiological processing. The results were analyzed statistically via chi-square, analysis of variance, and Games-Howell tests (P<.05).
Results:
Micro-organisms were isolated in approximately 94%, 10%, and 83% of canals, respectively, in MSCs 1, 2, and 3. There was a statistically significant difference only between MSCs 1 and 2 (P<.03). F nucleatum and black-pigmented rods were detected in approximately 56% and 11% of canals in MSC 1, respectively.
Conclusion:
Chemomechanical instrumentation and calcium hydroxide-based dressing have an anti-bacterial effect by significantly reducing the number of micro-organisms in the main root canal. They showed a limited efficacy, however, and did not prevent bacterial regrowth after endodontic therapy in primary teeth with pulp necrosis secondary to trauma.
