Abstract:
Background: Dental caries (decay or cavities) is a breakdown of teeth as a result of bacterial
activity. Lactobacillus bacteria play a major role in dental caries. The number of Lactobacillus is
related to the activity of another cariogenic bacteria, whose major role in initiating the caries
process. Caries is associated with pain, sepsis and reduced learning ability. Although effective
methods are known for prevention and management of the disease, the prevalence of dental caries
is increasing among school age children, predominantly in middle income countries. Despite the
fact that dental caries is affecting majority of the Ethiopian children, much is not known about the
extents and factors influencing the occurrence.
Objective: The main aim of this study was to determine the Prevalence of dental caries, salivary
Lactobacillus level and associated factors among primary school children in Harar, Eastern
Ethiopia from February 7 to March 14, 2018.
Methods: School-based cross-sectional study was conducted on 407 primary school children in
Harar, Ethiopia. The schools were selected by lottery method and study participants were selected
using systematic random sampling technique. The data were collected using structured
questionnaires to assess factors associated with dental caries and clinical examination was
conducted. Saliva samples were collected and transported to Medical Laboratory Science
department laboratory following the standard procedures. Microbiological saliva culture and
identification were conducted using de Man, Rogosa and Sharpe agar media and anaerobic 24hrs
culture. Data was entered into Epi data software version 3.1 and exported to Statistical Package
for Social Science software version 25.0 for analysis. Odds ratio was used to determine the
predictors of the outcome. Statistical significance was defined at a p value of less than 0.05.
Result: The prevalence of dental caries was 36.9%. The mean Decayed, Missing and Filled Teeth
value of the participants was 0.95 (SD±1.57). The decayed component accounted for 84.6% of the
total. About 67.1% of the saliva culture revealed significant Lactobacillus count. The mean
bacterial count was 14.92 x 105
(SD±22.92 x 105
). Previous year average academic score less than
fifty percent (AOR=3.68 95%, C.I=1.10-12.29), grade levels of children 1-4 (AOR = 1.73, 95%
CI = 1.02 – 2.92), sweet food consumption habit (AOR =4.08, 95%CI=1.62-10.25), absence of
daily teeth cleaning habit (AOR = 2.23, 95% CI = 1.32 – 3.78), absence of toothpaste use (AOR =
3.05, 95% CI: 1.69-5.49 P=0.001), dental ache history (AOR = 2.95, 95% CI = 1.78 – 4.89),
significant salivary Lactobacillus count (AOR = 4.01, 95% CI = 2.24-7.18), acidic and basic
salivary pH with (AOR = 1.93, 95% CI = 1.07-3.48) (AOR = 0.38, 95% CI = 0.17-0.88)
respectively were significantly associated with dental caries.
Conclusion: Dental caries is a common chronic infection among school children. Poor oral
hygiene, sweet diet, lower grade level and significant Lactobacillus count were found to be
significant determinant factors. Health information dissemination on oral hygiene and dietary
habits are obligatory to prevent dental caries among primary school children