Antimicrobial activity of antibiotic pastes used in pulp therapy through direct contact with a multispecies biofilm: a pilot study

Objective: To evaluate the antimicrobial activity of antibiotic pastes used in lesion sterilization and tissue repair (LSTR) technique, through a novel membrane direct contact methodology against a multispecies biofilm and to establish appropriate dilutions for this method. Methods: CTZ (chloramphenicol, tetracycline, zinc oxide) and two formulations of 3Mix pastes (ciprofloxacin, metronidazole, and minocycline), 3Mix1 and 3Mix3, were evaluated with negative (0.9% saline) and positive (chlorhexidine 0.2%) control groups. Candida albicans and Enterococcus faecalis (24-hour) biofilms (n=10) grown on cellulose membranes were directly exposed to standardized amounts of fresh pastes and control solutions (n=2) for 24h. Membranes were immersed in 900 µl of saline solution, and seven serial dilutions were made for each sample. Plating for each dilution (n=2) was performed on culture media for microbial colony-forming unit (CFU) counting of total microorganisms, Candida spp. and Enterococcus spp. Aiming the comparison between groups, CFU quantification data were transformed into log10 CFU / mL and the Mann-Whitney test was applied (p<0.05). Results: Inhibition of CFU was observed for all pastes, with greatest effects for CTZ paste in medium selective for Candida spp. (p<0.001) and 3Mix1 in non-selective (p<0.000) and selective for Enterococcus spp. (p<0.004). Conclusion: The pastes showed antimicrobial activity against the tested multispecies biofilm, and the proposed direct contact methodology was efficient. Moreover, the dilutions used proved to be appropriate for this methodology.

Objetivo: Avaliar a atividade antimicrobiana de pastas antibióticas utilizadas na técnica Lesion Sterilization and Tissue Repair (LSTR), através de nova metodologia de contato direto com membrana contra um biofilme multiespécies e estabelecer diluições adequadas para avaliação. Métodos: CTZ (cloranfenicol, tetraciclina,óxido de zinco) e duas formulações de pastas 3Mix (Ciprofloxacina, Metronidazol e Minociclina), 3Mix1 e 3Mix3, foram avaliadas, além dos grupos controle, negativo (solução salina a 0,9%) e positivo (clorexidina 0,2%). Biofilmes de Candida albicans e Enterococcus faecalis cultivados sobre membranas de celulose (n=10) durante24 h foram expostos diretamente em contato com quantidades padronizadas de pastas frescas e controles (n = 2) por 24 h. As membranas foram imersas em 900µL de solução salina e sete diluições seriadas foram obtidas por amostra. O plaqueamento para cada diluição (n = 2) foi realizado em meios de cultura para microrganismos totais e seletivos para Candida spp. e Enterococcus spp. para contagem de unidades formadoras de colônias (UFC). Para comparação entre grupos, os dados da contagem de UFC foram convertidos em log10 UFC / mL e o teste Mann-Whitney foi aplicado (p<0,05). Resultados: Observou-se inibição de UFC para todas as pastas, maior para CTZ no meio seletivo para Candida (p<0,001)e 3Mix1 nos demais meios (p<0,004). Conclusão: Concluiu-se que as pastas apresentaram atividade antimicrobiana contra o biofilme multiespécies testado e que a nova metodologia de contato direto proposta foi eficiente. Além disso, as diluições utilizadas mostraram-se adequadas para essa metodologia.

Iodoform Vs Calcium Hydroxide/Zinc Oxide based pastes: 12-month findings of a Randomized Controlled Trial.

This study evaluated clinical and radiographic twelve-month outcomes of root canal treatments (CT) with smear layer removal, performed in primary teeth, using two different root canal filling materials. Pulpectomy was performed on 27 primary teeth with necrosis or irreversible pulpitis, caused by dental caries or trauma, in 23 children (2-7 years old). A single trained operator performed the CT in a single visit in cases without periapical or interradicular radiolucency (PIR) or in multiple visits in cases with PIR. Participants were selected based on specific inclusion and exclusion criteria, and randomly allocated into two groups: Group 1 (G1) - iodoform paste (iodoform + camphorated parachlorophenol + ointment comprising prednisolone acetate 5.0 mg and rifamycin 1.5 mg); Group 2 (G2) - Calen®/ZO paste. Treated teeth were restored with composite resin immediately after the root canal filling. The outcomes were evaluated clinically and radiographically according to specific criteria. Two blinded and standardized evaluators assessed the radiographic outcomes. We used descriptive analyses due to the small sample size. CTs were performed due to caries lesions in 70.4% of the cases and due to trauma in 29.6%. Only one tooth of G1 was unsuccessful; hence, pulpectomy performance in both groups was not influenced by the filling material, nor by any other analyzed variable. The level of the root canal filling was better in the Calen®/ZO group. The clinical and radiographic twelve-month outcomes indicated successful treatment, independently of the root filling material used.

Iodoform Vs Calcium Hydroxide/Zinc Oxide based pastes: 12-month findings of a Randomized Controlled Trial

Abstract This study evaluated clinical and radiographic twelve-month outcomes of root canal treatments (CT) with smear layer removal, performed in primary teeth, using two different root canal filling materials. Pulpectomy was performed on 27 primary teeth with necrosis or irreversible pulpitis, caused by dental caries or trauma, in 23 children (2-7 years old). A single trained operator performed the CT in a single visit in cases without periapical or interradicular radiolucency (PIR) or in multiple visits in cases with PIR. Participants were selected based on specific inclusion and exclusion criteria, and randomly allocated into two groups: Group 1 (G1) - iodoform paste (iodoform + camphorated parachlorophenol + ointment comprising prednisolone acetate 5.0 mg and rifamycin 1.5 mg); Group 2 (G2) - Calen®/ZO paste. Treated teeth were restored with composite resin immediately after the root canal filling. The outcomes were evaluated clinically and radiographically according to specific criteria. Two blinded and standardized evaluators assessed the radiographic outcomes. We used descriptive analyses due to the small sample size. CTs were performed due to caries lesions in 70.4% of the cases and due to trauma in 29.6%. Only one tooth of G1 was unsuccessful; hence, pulpectomy performance in both groups was not influenced by the filling material, nor by any other analyzed variable. The level of the root canal filling was better in the Calen®/ZO group. The clinical and radiographic twelve-month outcomes indicated successful treatment, independently of the root filling material used.