Tooth decay is an infection due to demineralization and destruction of the hard tissues of the teeth by oral microbes. It is as a result of production of acid by bacterial fermentation of food debris accumulated on the tooth surface. Depending on the extent of tooth destruction, various treatments can be used to restore teeth to normality, but there is no known method to regenerate large amounts of tooth structure. Instead, Dental Health Organizations advocates preventive and prophylactic measures, such as regular oral hygiene and dietary modifications to avoid dental caries. Herbal remedies have a long history of use for gum and tooth problem such as dental caries. Solanum incanum L. fruits are locally used to manage the tooth decay which is caused by mouth microbes. In this study, the effect of Solanum incanum fruit extracts on growth of oral microbes was investigated. When the microbes were treated with Solanum incanum fruit extract at concentration; 10 μl, 20 μl, 30 μl, and 40 μl, 50 μl, 60 μl, 70 μl, 90 μl and 100 μl respectively, the optimum concentration obtained was 70 μl. Similarly, laboratory observations showed that the betadine mouth wash used worked as best as Solanum incanum fruit extract with the optimum concentration attained at 70 μl. There was no significance difference on the inhibitory effects of both betadine mouth wash and Solanum incanum fruit extracts on oral microbes but on close observation of regression analysis models betadine had more inhibitory effects than Solanum incanum fruit extracts.