Relationship of Salivary Lactoferrin and Lysozyme Concentrations with Early Childhood Caries

Abstract

Background and aims. Lysozyme and lactoferrin are salivary proteins which play an important role in innate defense mechanisms against bacteria. This study investigated the association of salivary lysozyme and lactoferrin concentrations with early childhood caries (ECC).Materials and methods. This study was carried out on 42 healthy children (age range, 36 to 71 months), of whom 21 were caries free (CF) and 21 had ECC. Disposable needle-less syringes were used to collect unstimulated saliva from buccal and labial vestibules. Fifteen children who had ECC were treated completely and their saliva was collected in the same way for the second time, three months after treatment. Lysozyme and lactoferrin concentrations were measured and recorded by the ELISA method. The intergroup comparisons were carried out using chi-square, Student’s t-test and Wilcoxon signed ranked test. A P-value less than 0.05 was considered as statistically significant.Results. The mean concentration of lysozyme was significantly higher in CF group compared with that of ECC group (P = 0.04). Although the mean concentration of lactoferrin in ECC group was higher in comparison with ECC group, the difference was not statistically significant (P = 0.06). After dental treatment, the mean concentrations of lysozyme and lactoferrin did not change in comparison with their concentrations before treatment.Conclusion. ECC may have a relationship with lower concentrations of unstimulated salivary lactoferrin and lysozyme and reduced amounts of these two salivary proteins may be a risk factor for dental caries in children.

Associação entre a diminuição do nível de ferro salivar e a experiência de cárie em crianças

“…Interestingly, Streptococci are bacteria that can grow under limited iron conditions [24], which may explain the caries experience in children with reduced salivary iron levels. Another hypothesis is that the lower availability of salivary iron does not inhibit the activity of the glycosyltransferase enzyme, which is responsible for producing insoluble extracellular polysaccharides that in turn confer an ecological advantage to cariogenic bacteria [25]. Finally, one issue is whether it is possible to predict anemia using saliva samples.…”

sIgA and Lisozim as Biomarker of Early Childhood Caries Risk

“…The study also evaluated 3 months later, after all carious teeth performed dental treatment. There was no difference in lysozyme value between baseline values before dental treatment compared with after dental treatment, although substantially higher lysozyme value was in after dental treatment than baseline [26]. Bhalla's study [52] also obtained a DMF-T index decreasing as the concentration of lysozyme increased.…”

“…Lysozyme activity as antimicrobial relates to its ability in lytic action in bacteria [43] by hydrolyzing β (1-4) bonds between N-acetylmuramic acid and Nacetylglucosamine in peptidoglycan layer of bacterial cell wall [26]. Glycosidic bond hydrolysis results will cause the occurrence of small pores inside bacterial cell wall so that bacteria will die.…”

“…Lysozyme as a strong cationic protein, can also mediate bacterial aggregation and inhibit bacterial attachment and also activate bacterial autolysin by destroying bacterial cell walls [26,43]. The lysozyme activity will survive when the enzyme is absorbed in the pellicle [45].…”

“…Study found that there was an association between lysozyme value and the number of S. mutans and lactobacillus [25]. Other studies reported that lysozyme concentration in unstimulated saliva was significantly higher in the caries-free group compared with ECC group [26].…”