Background: The human mouth harbors one of the most diverse microbiomes in the human body. Multiple factors might affect the composition of oral flora, such as oral hygienic practices. Disturbance in the composition of the oral flora might lead to local as well as systemic diseases.
Objective(s): To estimate the occurrence of some oral potentially pathogenic microorganisms and their associated risk factors, as well as their association with dental caries.
Methods: Saliva samples were collected from 130 participants affiliated to the High Institute of Public Health (HIPH) including university teaching staff/ postgraduate students, administrative employees and workers. A questionnaire sheet was completed for everyone. It included demographic data, clinical data as well as oral hygienic practices. The DMFT index was recorded as an index for oral caries. All 130 saliva samples were examined for the presence of Enterobacteriaceae, Streptococcus mutans (S. mutans) and Candida spp. Demographic data, dental hygiene practices, dental complaints as well as the DMFT index were all studied in relation to the studied microbial agents.
Results: The most prevalent microorganism among participants was S. mutans (64.6% of isolates) followed by Candida spp (20.8%) then Enterobacteriaceae spp (10%). Isolates of Enterobacteriaceae spp were distributed as follows: Citrobacter koseri (4.6%), followed by Klebsiella pneumoniae (3.8%), then Klebsiella oxytoca. S. mutans was the only microorganism that was significantly affected by the type of snacks taken between meals (p=0.001). Among those who had sugary snacks between meals, S. mutans was isolated in 81.3% of them. Candida spp was present in 27.3% of married participants, and this finding was statistically significant. The intake of drinks between meals was also significantly associated with positive Candida cultures (31.1% of participants who took drinks in between meals had positive Candida cultures). Enterobacteriaceae were significantly less frequently isolated among participants with secondary and university education (5% and 6.5% respectively) compared to uneducated and primarily educated participants (13% and 40% respectively). None of the studied microorganisms were associated with any specific dental hygienic practice, or specific dental symptoms and signs. The only organism isolated that was significantly associated with DMFT index was S. mutans (p = 0.001). None of the microorganisms were found to be significantly associated with the presence of any of the other two microorganisms.
Conclusions: S. mutans was the most prevalent microorganism among participants andwas significantly associated with higher DMFT index. The presence of potentially pathogenic oral microorganisms was influenced mainly by the educational status as well as dietary habits (the intake of sugars and drinks between meals) rather than specific oral hygienic practices.