Salivary Candida Species Carriage Patterns and Their Relation to Caries Experience Among Yemeni Children

Purpose: This study was carried out to assess the carriage rates, counts and species distribution of Candida in saliva of 6- to 12-year-old Yemeni children and relate that to their caries experience. Materials and Methods: One hundred eighty children were recruited. Oral hygiene and caries were assessed using the simplified oral hygiene index and dft/DMFT index, respectively. Detection and quantification of 4 Candida species in unstimulated saliva were performed using CHROMagar Candida medium. Data were analysed using regression analysis. Results: Candida was detected in 60% of the children with a mean count of 923 ± 1875 CFU/ml. C. albicans accounted for 60% of the isolates and was the only species to be detected with more than 1000 CFU/ml. Non-albicans candida and unidentified species represented 16.3% and 23.1% of the isolates, respectively. One novel finding was that a significant proportion (38%) of the carriers harboured two or more species, which for the first time allowed the identification of four age-dependent carriage patterns (clusters). Another somewhat new observation was that carriage at ≥ 1000 CFU/ml in particular significantly correlated with caries in primary and permanent dentitions (r = 0.23 and 0.18, respectively) as well as a caries-active status (OR = 6.9). Interestingly, the C. glabrata cluster had significantly lower primary caries scores than other clusters. Conclusions: The findings substantiate claims of geographical variations in candida carriage and the relation between candida carriage and caries. The validity of carrier clusters and the use of 1000 CFU/ml as a risk marker should be further investigated. Keywords: candida species, dental caries, aetiology, risk factors, saliva