Antimicrobial Efficacy of Salvadora persica Extracts on a Monospecies Biofilm on Orthodontic Brackets In Vitro.

PURPOSE: The oral cavity is a rich ecosystem with a plethora of microorganisms, and different components of fixed orthodontic appliances may contribute to a shift in the balance of oral ecology. The purpose of this study was to investigate the antimicrobial potential of hexane and ethanol extracts of Salvadora persica on a monospecies biofilm model established on orthodontic brackets in vitro. MATERIALS AND METHODS: Streptococcus mutans biofilm was formed on mini diamond orthodontic brackets following three days of anaerobic incubation at 37˚C. The bacterial cell viability of this biofilm was measured after their exposure to saline, hexane extract of S. persica, ethanol extract of S. persica and 0.2% chlorhexidine using 3-(4, 5-dimethylthiazol- 2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulphophenyl)-2H-tetrazolium (MTS) assay. On half of the brackets, the colony forming units (CFU) were counted. Both experiments were performed in triplicate. RESULTS: The absorbance values obtained from the MTS reduction assay after exposure to the different test agents showed a decline in the bacterial cell viability of the S. mutans biofilm as follows: chlorhexidine (+)0.05). The CFU counts of S. mutans obtained from chlorhexidine exposure were lower than from hexane and ethanol extracts. CONCLUSION: S. persica extracts were found to have antimicrobial effects on S. mutans biofilm established in vitro on orthodontic brackets suggestive of its potential use as an oral antimicrobial agent for orthodontic patients.

Evaluation of different irrigating solutions on smear layer removal of primary root dentin.

AIM: To evaluate the efficacy of ethanolic extract of Salvadora persica (S. persica) and BioPure MTAD (a mixture of a tetracycline isomer, an acid, and a detergent) in removing the intracanal smear layer of primary teeth. MATERIALS AND METHODS: The root canal of 40 extracted human primary anterior teeth were cleaned, shaped and grouped into experimental (n = 30) and control (n = 10). The root canals of the positive (n = 5) and the negative control (n = 5) were irrigated for 3 minutes with 5 ml of 17% ethylenediaminetetraacetic acid (EDTA) or saline respectively. The canals in the experimental groups were irrigated for 3 minutes with 5 ml of 1 mg/ml ethanolic extract of S. persica (n = 15) or BioPure MTAD (n = 15) and then flushed with 2 ml of saline. The presence or absence of smear layer at the coronal and middle portion of each canal were examined under a scanning electron microscope (SEM). RESULTS: A significant difference (p = 0.004) in smear layer removal between S. persica and MTAD at the middle third of the canal was observed. MTAD solution was as effective as 17% EDTA in removing the smear layer. CONCLUSION: MTAD was significantly more effective in smear layer removal than S. persica solution at the middle third of the canal wall. CLINICAL SIGNIFICANCE: Both tested irrigant solutions have the ability to remove the intracanal smear from primary root dentin following cleaning and shaping of the root canal and could be an alternative to EDTA.

Cytotoxic effect of Salvadora persica extracts on human gingival fibroblast cells.

OBJECTIVES: To assess the cytotoxic potential of Salvadora persica (S. persica) extracts on human gingival fibroblast (HGF) cells. METHODS: This study was conducted between January and May 2012 in collaboration with Dental Caries Research Chair, College of Dentistry, King Saud University, Riyadh, Saudi Arabia. Extracts of S. persica using hexane, ethylacetate, and ethanol as solvents at concentrations of 0.5 mg/ml and 1 mg/ml were evaluated for their cytotoxic activity against HGFs using the 3 cytotoxic assays: (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, a tetrazole) (MTS), lactic dehydrogenase (LDH), and crystal violet (CV). International standards for the evaluation of medical materials recommended cut-off value of cell survival >70% was used for interpretation of the results. RESULTS: Ethanol extract of S. persica at 0.5 mg/ml and 1 mg/ml and hexane extract of S. persica at 0.5 mg/ml were completely devoid of cytotoxic activity, hexane extract at 1 mg/ml in comparison with controls  demonstrated some cytotoxicity with cell survival of 88% (p=0.045) in MTS, 86% (p=0.01) in LDH, and 88% (p=0.002) in CV assays. Similarly, ethyl acetate extract of S. persica at 0.5 mg/ml maintained cell viability of 91% in MTS, 81% in LDH, and 80% in CV assays. Maximum cytotoxicity against HGFs was observed with ethyl acetate extract of S. persica at 1 mg/ml with cell survival of 60% in MTS, 40% in LDH, and 66% CV assays (p=0.0001).   CONCLUSION: The acceptable level of cytotoxicity associated with S. persica ethanol and hexane extracts requires further evaluation to be used as irrigation solutions in endodontic treatment.