Effectiveness of castor oil extract on Escherichia coli and its endotoxins in root canals.
This in vitro study sought to evaluate the effectiveness of castor oil extract used as an irrigating solution on Escherichia coli and its endotoxins in root canals. Sixty single-rooted teeth were prepared (using castor oil extract as irrigating solution) and divided into five groups (n = 12): Group 1 samples were treated with calcium hydroxide (Ca(OH)2), Group 2 samples were treated with polymyxin B, Group 3 samples were treated with Ca(OH)2 and 2% chlorhexidine gel (CHX), and Group 4 samples were treated with castor oil extract. A control group used physiological saline solution as an irrigant. Canal content samples were collected at four different times: immediately after instrumentation, seven days after instrumentation, after 14 days of intracanal medication, and seven days after removal of intracanal medication. A plating method was used to assess antimicrobial activity and the quantification of endotoxins was evaluated by the chromogenic Limulus lysate assay. Data were submitted to ANOVA and a Dunn test (a = 5%).  Irrigation with castor oil extract decreased E. coli counts but had no effect on the level of endotoxins. Samples taken seven days after removal of medication revealed a significant reduction in endotoxin levels in Groups 3 and 4. Compared to the saline solution irrigation, castor oil extract decreased microorganism counts in root canals immediately after canal preparation. None of the medications used completely eliminated endotoxins in the root canal.
Department of Restorative Dentistry, Sao Paulo State University, Sao Jose dos Campos Sao Paulo, Brazil.
Marcia Carneiro
MC
Valera
Lilian Eiko
LE
Maekawa
Adriana
A
Chung
Luciane Dias
LD
de Oliveira
Claudio Antonio Talge
CA
Carvalho
Cristiane Yumi
CY
Koga-Ito
Antonio Olavo Cardoso
AO
Jorge
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000891:Anti-Infective Agents, Local / Q000494:pharmacology; D058491:Bacterial Load / Q000187:drug effects; D002126:Calcium Hydroxide / Q000494:pharmacology; D002368:Castor Oil / Q000494:pharmacology*; D002710:Chlorhexidine / Q000494:pharmacology; D002863:Chromogenic Compounds; D003786:Dental Pulp Cavity / Q000187:drug effects / Q000382:microbiology*; D004731:Endotoxins / Q000037:antagonists & inhibitors*; D004926:Escherichia coli / Q000187:drug effects*; D006801:Humans; D008033:Limulus Test; D008070:Lipopolysaccharides / Q000037:antagonists & inhibitors*; D008422:Materials Testing; D010936:Plant Extracts / Q000494:pharmacology*; D011112:Polymyxin B / Q000494:pharmacology; D012388:Root Canal Irrigants / Q000494:pharmacology; D012965:Sodium Chloride; D013997:Time Factors
D000900:Anti-Bacterial Agents; D000891:Anti-Infective Agents, Local; D002863:Chromogenic Compounds; D004731:Endotoxins; D008070:Lipopolysaccharides; D010936:Plant Extracts; D012388:Root Canal Irrigants; D012965:Sodium Chloride; C044101:endotoxin, Escherichia coli; D002368:Castor Oil; D011112:Polymyxin B; D002126:Calcium Hydroxide; D002710:Chlorhexidine