Heba M. A. Darwish, Mostafa A. M. Hassan, Eman A. Abou Auf And Reham A.F.Dwedar,

ABSTRACT
The Present Investigation Was Conducted To Assess And Compare The Antimicrobial Effect Of Five Traditional Plant Extracts (green Tea, Guava Leaves, Coffee, Clove And Ginger) Against Common Cariogenic Microorganisms. The Samples Of The Study Were Divided Into Two Main Groups Of 125 Filter Paper Discs Each, According To The Type Of The Inoculated Bacteria; B1: Streptococcus Mutans Group And B2: Lactobacillus Acidophilus Group. Then Each Group Was Further Subdivided Into Five Equal Subgroups Of 25 Discs Each, According To The Type Of Plant Extract Tested. The Cultivation Of The Plant Extracts Discs On The Culture Media Was Done Using The ?disc Diffusion Method?. The Antibacterial Behavior Of Each Plant Extract Was Assessed By Measuring The Diameter Of The Inhibition Zones By Millimeters In Comparison To The Positive Control (antibiotic Disc) And Negative Control (distilled Water Disc). The Results Showed That The Only Potent Antibacterial Plant Extracts Against Streptococcus Mutans And Lactobacillus Acidophilus Were Green Tea And Ginger. Guava And Clove Extracts Showed Antibacterial Effect On The Streptococcus Mutans Only, While Coffee Extract Showed Antimicrobial Effect Against Lactobacillus Acidophilus Only.