Bacterial leakage in root canals filled with calcium hydroxide paste associated with different vehicles

Abstract

This in vitro study evaluated, using a bacterial leakage model, whether intracanal medication with calcium hydroxide [Ca(OH) 2 ]-based pastes prepared with different vehicles, has inhibitory effect on corono-apical leakage of bacteria. Forty instrumented human canines were dressed with Ca(OH) 2 p.a. associated with: G1= distilled water; G2= polyethylene glycol (PG); G3= PG + CMCP; and G4= glycerin. Five teeth with intact crowns served as negative controls and 5 instrumented teeth without temporary dressing served as positive controls. All teeth were mounted in a 2-chamber apparatus and then exposed to human saliva for 63 days. Leakage was recorded when turbidity was observed in the lower chamber. Fifty percent of the samples of G1 and G2, 10% of G3 and 80% of G4 were fully contaminated after 9 weeks. Statistically significant differences were observed with paired comparisons G3 and G4 (p=0.0069), with G3 achieving better seal against bacterial leakage than G4.

Antibacterial effectiveness in vitro of different formulations of calcium hydroxide paste

“…In view of this, Ca(OH) 2 powder has been combined with different vehicles, such as distilled water (DW), saline solution, camphorated p-monochlorophenol (CMCP), chlorhexidine, polyethylene glycol, propylene glycol (PG), Otosporin (O), glycerine 12 , and also with chlorhexidine gel [13][14] , in an attempt to improve its antibacterial activity, biocompatibility, speed of ion dissociation and diffusion 11 . Many studies have compared the effectiveness of calcium hydroxide pastes and the use of various vehicles in several respects, namely: the inhibitory behavior towards bacterial infiltration via the crown 15 ; the relationship of each vehicle with the potential for the diffusion of the calcium hydroxide paste into the dentin tubules 16 ; and the degradation of these pastes over the course of time 17 that results in a greater or lesser degree of substantivity and effectiveness against endodontic pathogens.…”

Efeitos da dentina sobre o pH e atividade antimicrobiana de diversas formulações com hidróxido de cálcio

“…Apesar de apresentar satisfatória atividade antimicrobiana e neutralizante de subprodutos da microbiota presente na infecção endodôntica primária, tais como a endotoxina, sua ação sobre o Enterococcus faecalis é restrita [2][3][4][5] .…”

“…Por outro lado, essas associações também podem ocasionar efeitos adversos sobre as propriedades biológicas e microbiológicas da própria medicação 4,5 .…”

High-resolution X-ray microdiffraction analysis of NaOH-treated dentin

“…Dentin is the most functional tissue in the tooth and the most susceptible to damage; it plays an important role in nourishing the enamel and preventing a tooth from fracturing. Various kinds of chemicals interact with dentin in different clinical conditions such as dentin bonding (Yazici et al, 2009), dental pulp capping (Accorinte, Holland et al, 2008), root canal therapy (Murad et al, 2008) and dentin hypersensitivity treatment (Suge et al, 1995(Suge et al, , 2002. However, these chemicals may cause the destruction of dentin (Jiang et al, 2007), which may lead to unpleasant effects such as making the tooth vulnerable to fracture or staining of the tooth.…”