Biofilm biomass disruption by natural substances with potential for endodontic use

This study evaluated the in vitro effects of four natural substances on the biomass of bacterial biofilms to assess their potential use as root canal irrigants. The following substances and their combinations were tested: 0.2% farnesol; 5% xylitol; 20% xylitol; 0.2% farnesol and 5% xylitol; 0.2% farnesol, 5% xylitol, and 0.1% lactoferrin; 5% xylitol and 0.1% lactoferrin; and 20 mM salicylic acid. The crystal violet assay was used to evaluate the effects of these substances on the biomass of biofilms formed by Enterococcus faecalis and Staphylococcus epidermidis. All substances except for 20 mM salicylic acid and 20% xylitol reduced biofilm mass when compared to controls. The combination of farnesol and xylitol was the most effective agent against E. faecalis ATCC 29212 (p < 0.05). Farnesol combined with xylitol and lactoferrin was the most effective against biofilms of the endodontic strain of E. faecalis MB35 (p < 0.05). Similarly, combinations involving farnesol, xylitol, and lactoferrin reduced the biomass of S. epidermidis biofilms. In general, farnesol, xylitol, and lactoferrin or farnesol and xylitol reduced biofilm biomass most effectively. Therefore, it was concluded that combinations of antibiofilm substances have potential use in endodontic treatment to combat biofilms.

Princípios biológicos do tratamento endodôntico de dentes com polpa necrosada e lesão perirradicular / Biological principles of endodontic treatment of teeth with pulp necrosis and apical lesions

O profissional que pratica a Endodontia se depara rotineiramente com três condições básicas que requerem tratamento endodôntico: polpas vitais, polpas necrosadas e casos de retratamento. O sucesso do tratamento endodôntico depende do reconhecimento das idiossincrasias de cada uma destas três condições. Canais radiculares contendo polpa necrosada e lesão perirradicular representam um problema infeccioso e devem ser tratados de forma diferenciada dos dentes com polpa viva (sem infecção). O sucesso do tratamento endodôntico nestes casos vai depender do controle da infecção exercido pelo preparo químico-mecânico, medicação intracanal e obturação. Este artigo revisa os princípios biológicos do tratamento de dentes com polpa necrosada e infectada, visando fornecer ao clínico as condições para a melhora no resultado do tratamento endodôntico destes casos.

The clinician who practices endodontics routinely faces three conditions that require treatment: vital pulps, necrotic pulps and retreatment cases. The successful treatment of these three conditions depends on the recognition of their respective idiosyncrasies. Canals of necrotic teeth associated with apical periodontitis represent an infectious problem and should be treated differently from vital teeth (non-infected). The success of the endodontic treatment will depend on effective infection control promoted by chemomechanical preparation, intracanal medication and obturation. This paper reviews the biologic principles of the endodontic treatment of teeth with necrotic pulps and apical periodontitis, with the purpose to provide the clinician with better conditions to improve the treatment outcome.

Microbial colonization in orthodontic mini-implants

Peri-implant inflammation contributes for loss of secondary stability of orthodontic mini-implants. The investigation of microbial colonization in this area would benefit its control, and consequently favor the long-term success of mini-implants. Therefore, the aim of this study was to determine the establishment and the evolution of microbial colonization process in orthodontic mini-implants for 3 months, since the time of their installation. One-hundred and fifty samples collected from 15 mini-implants were investigated from baseline up to 3 months. The biological material was obtained from peri-implant area using paper points. Nonspecific, Streptococcus spp, Lactobacillus casei and Candida spp colonizations were analyzed by cell growth methods. Porphyromonas gingivalis colonization was observed by 16S rDNA-directed polymerase chain reaction. Data from cell growth were submitted to the Wilcoxon sign rank test and results from molecular analysis were presented in a descriptive way. There was no significant difference in the microbial colonization among the examined time intervals, except for Streptococcus spp, between baseline and 24 h, which characterized the initial colonization in this time interval. Lactobacillus casei and Candida spp colonizations were insignificant. No Porphyromonas gingivalis was detected among the analyzed samples. The microbial colonization of mini-implants did not significantly change during the study. However, it should be monitored by orthodontists, since it is an important factor for mini-implants success.

A inflamação peri-implantar contribui para a perda da estabilidade secundária dos mini-implantes ortodônticos. A investigação da colonização microbiana desta área beneficiaria o seu controle e, consequentemente, favoreceria o sucesso dos mini-implantes a longo prazo. Portanto, o objetivo dos autores foi determinar o estabelecimento e evolução do processo de colonização microbiana em mini-implantes ortodônticos por três meses desde a instalação. Cento e cinquenta amostras coletadas de 15 mini-implantes foram investigadas desde o tempo inicial até 3 meses. O material biológico foi obtido da área peri-implantar com auxílio de cones de papel absorvente. As colonizações inespecíficas de Streptococcus spp, Lactobacillus casei e Candida spp foram analisadas por métodos de crescimento celular. A colonização por Porphyromonas gingivalis foi observada por meio da reação em cadeia da polimerase 16S rDNA. Os dados do crescimento celular foram submetidos ao teste de Wilcoxon sign rank e os resultados da biologia molecular foram apresentados de modo descritivo. Não houve diferença estatisticamente significante da colonização microbiana entre os intervalos de tempo avaliados, exceto para Streptococcus spp entre os tempos inicial e 24 h, o que caracterizou o início da colonização neste intervalo de tempo. As colonizações por Lactobacillus casei e Candida spp foram insignificantes. Não foi detectada a presença de Porphyromonas gingivalis nas amostras analisadas. A colonização microbiana nos mini-implantes não se alterou significativamente durante o estudo. No entanto, deve ser monitorada por ortodontistas, uma vez que é um fator importante para o sucesso dos mini-implantes.