# Propolis as Natural Product in the Oral Cavity Bacterial Infections Treatment: A Systematic Review
## 4 Results
### Antibacterial Activity of Propolis in Oral Cavity Bacterial Infections
#### 4.2.1 In Vitro Studies
Ethanol (70%, _v/v_) and chlorhexidine (0.12%, _w/w_) were used as negative and positive controls, respectively. Inhibition zones ranging from 10 to 13 mm in diameter for _S. mutans_, and no activity against _L. acidophilus_ were detected in case of HAE-2 and HAE-3. The average of MBCs for HAE-2, its chloroform fraction, and HAE-3 against _S. mutans_ are presented in Table 3. What is more, HAE-2 had bactericidal effects on _S. mutans_ biofilms after 3 h of treatment. The total concentrations of phenol and flavonoid were significantly different in various samples [66]. The ethanolic and aqueous extracts of the Iranian propolisis collected in the northeast area of Tehran were used to evaluate propolisis antimicrobial activity against _S. mutans_, _S. salivarius_, and _L. casei_. The study was conducted by [PERSON] et al. [15]. It could be concluded that the ethanolic extract of Iranian propolisis effective when oral biofilms and subsequent dental caries development need to be controlled. The zones of growth inhibition, MIC, and MBC were measured. The inhibition zones were 16.00 \(\pm\) 0.00, 20.00 \(\pm\) 1.00, and 12.00 \(\pm\) 1.00 mm (ethanolic extract of propolis) for _S. mutans_, _S. salivarius_, and _L. casei_, respectively, and 12.00 \(\pm\) 1.00 mm (water extract of propolis) for _S. mutans_. The obtained results showed that the ethanolic extract had bacteriostatic and bactericidal activity against all the strains (Table 3). On the other hand, the aqueous extract was bactericidal only against _S. mutans_[15]. [PERSON] et al. [67] compared the activity of calcium hydroxide and propolis against _Lactobacillus spp_. They carried out an experimental study in order to assess the antimicrobial activity of ethanol extract of propolis and calcium hydroxide (Ca(OH)\({}_{2}\)) powder mixed with saline solution. The diameter of the inhibition zone, MIC, and MBC was determined. The authors indicated that propolisis was more effective against _Lactobacillus spp_. with 8.42 mm compared with the 7.0 mm mean diameter of the inhibitory zone for Ca(OH)\({}_{2}\). In addition, the MIC and MBC values of propolisis were lower than those of calcium hydroxide (Table 3) [67]. [PERSON] [31] determined the antibacterial actions of aqueous propolisis extract against black pigmented _P. gingivalis_ (from periodontal pockets). The results indicated that propolisis had antibacterial actions against _P. gingivalis_, and it might be employed to treat periodontal diseases. Additionally, it can be one of substances beneficial for prophylactic procedures. These results were obtained based on a study in which swabs taken from the periodontal pockets of 30 patients were used. The antimicrobial activity of propolisis by the well-diffusion method was characterized by inhibition zones. At 50% concentration of propolisis, the inhibition zone was 30 mm [31]. The antimicrobial activities of neovestitol and vestitol isolated from Brazilian red propolisis (BRP) were evaluated by [PERSON] et al. [68]. The results indicated that propolisis can be useful in pharmaceutical treatment due to its antimicrobial activities. These results were obtained based on evaluating MIC and MBC against _S. mutans_, and _S. sobrinus_. The obtained MIC and MBC values of ethanol propolisis extract (EEP) are presented in Table 3[68]. [PERSON] et al. [69] studied the antimicrobial properties of the ethanolic extract of geopropolis (EEGP) against _S. mutans_ and _A. naslundii_. EEGP was collected by _Melipona scutellaris_. The authors evaluated also the antiproliferative activity of EEGP and its bioactive fraction. MIC and MBC were determined to analyze the antimicrobial activity of EEGP and fractions, and the results are presented in Table 3. This suggests that geopropolis may be a good source of antibiofilm agents as well as possesses antimicrobial activity [69]. [PERSON] et al. [70], in their ex vivo study, examined the antibacterial properties of ethanol extract of propolisis (EEP) against cariogenic bacteria: salivary _S. mutans_ and _Lactobacillus spp_.