Microbial culture and checkerboard DNA-DNA hybridization assessment of bacteria in root canals of primary teeth pre- and post-endodontic therapy with a calcium hydroxide/chlorhexidine paste

Autor(es)

Ito, Izabel Yoko ^{[1, 2]} ; Matoba Junior, Fumio ^[1] ; Garcia Paula-Silva, Francisco Wanderley ^[1] ; Bezerra Da Silva, Lea Assed ^[1] ; Leonardo, Mario Roberto ^[1] ; Nelson-Filho, Paulo ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Pediat Clin Prevent & Social Dent, Sch Dent Ribeirao Preto, BR-14040904 Ribeirao Preto, SP - Brazil

^[2] Sch Pharmaceut Sci Ribeirao Preto, Dept Clin Anal Toxicol & Bromatol, Ribeirao Preto, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: International Journal of Paediatric Dentistry; v. 21, n. 5, p. 353-360, SEP 2011.
• Citações Web of Science: 15

Resumo

Aim. To investigate the root canal microbiota of primary teeth with apical periodontitis and the in vivo antimicrobial effects of a calcium hydroxide/chlorhexidine paste used as root canal dressing. Design. Baseline samples were collected from 30 root canals of primary teeth with apical periodontitis. Then, the root canals were filled with a calcium hydroxide paste containing 1% chlorhexidine for 14 days and the second bacteriologic samples were taken prior to root canal filling. Samples were submitted to microbiologic culture procedure to detect root canal bacteria and processed for checkerboard DNA-DNA hybridization. Results. Baseline microbial culture revealed high prevalence and cfu number of anaerobic, black-pigmented bacteroides, Streptococcus, and aerobic microorganisms. Following root canal dressing, the overall number of cfu was dramatically diminished compared to initial contamination (P < 0.05), although prevalence did not change (P > 0.05). Of 35 probes used for checkerboard DNA-DNA hybridization, 31 (88.57%) were present at baseline, and following root canal dressing, the number of positive probes reduced to 13 (37.14%). Similarly, the number of bacterial cells diminished folowing application of calcium hydroxide/chlorhexidine root canal dressing (P = 0.006). Conclusion. Apical periodontitis is caused by a polymicrobial infection, and a calcium hydroxide/chlorhexidine paste is effective in reducing the number of bacteria inside root canals when applied as a root canal dressing. (AU)

• Processo FAPESP: 04/02263-0 - Biologia molecular - utilizacao da tecnica "checkerboard dna-dna hybridization" para a identificacao da microbiota de canais radiculares de dentes deciduos de humanos.
• Beneficiário: Paulo Nelson Filho
• Modalidade de apoio: Auxílio à Pesquisa - Regular