Abstract
This study included the role of Leuconostoc mesenteroides subsp. cremoris in oral diseases such as periodontitis. Material and Method. Isolation and identification of Leuconostoc mesenteroides subsp. cremoris from a saliva sample of twenty patients wearing fixed dental prostheses suffering from periodontitis followed by estimating susceptibility generally to the most common antibiotics and specifically to chlorhexidine (CHX) to determine the MIC of CHX and also screening of the strength of biofilm production under aerobic and anaerobic conditions; here, the study included six groups: Group I: screening of biofilm formation under aerobic condition, Group II: screening the MIC of CHX effect on biofilm formation under aerobic condition, Group III: screening of the MIC of CHX effect on preformed biofilm under aerobic condition, Group IV: screening of biofilm formation under anaerobic condition, Group V: screening of MIC of CHX effect on biofilm formation under anaerobic condition, and Group VI: screening of MIC of CHX effect on preformed biofilm under anaerobic condition. Results. The results showed that about 5 (25%) isolates were identified as L. mesenteroides subsp. cremoris, while 75% are other isolates. Furthermore, susceptibility results to antibiotic showed the sensitivity to penicillin (100%), azithromycin (100%), ciprofloxacin (100%), tetracycline (100%), gentamicin (100%), doxycycline (100%), vancomycin (100%), ofloxacin (60%), chloramphenicol (80%), ampicillin (80%), and cefoxitin (60%). On the other side, the biofilm production assays revealed that all isolates were moderate biofilm former under the aerobic and anaerobic conditions but for the biofilm treated with MIC of CHX, the current study noticed that the strength of the biofilm became weaker in aerobic and anaerobic conditions; regardless, the strength of the biofilm under anaerobic conditions was higher than in that under aerobic conditions, with no significant differences at p ≤ 0.05 depending on the statistical analysis (T-test) before and after the treatment with MIC of CHX in aerobic and anaerobic conditions. Conclusions. The presence of mesenteroides subsp. cremoris in the oral cavity is due to eating foods and vegetables; based on the strength of the biofilm and sensitivity tests, the isolates have less pathogenicity in the oral cavity due to the weakness of the biofilm production and the lack of resistance to antibiotics.