Salivary Lysozyme in Relation to Dental Caries among Thai Preschoolers

The objective of this study was to analyze salivary lysozyme levels and activities in Thai preschoolers with different dental caries status. Study design: Unstimulated saliva samples were collected from 64 preschoolers, divided into a caries free group (n = 32) and a severe early childhood caries (S-ECC) group (n = 32). Results: Both groups were similar regarding gender, age, dental caries status, salivary flow rate, and salivary protein concentrations. No differences were also in the caregivers´ characteristics, oral health behaviors, and feeding habits. Only professional fluoride application was less frequently found in the S-ECC group (p < 0.03). Western blotting and lysoplate assays revealed that salivary lysozyme levels and activities were significantly increased in the S-ECC group compared with the caries free group (p< 0.001; p = 0.008, respectively). Conclusion: The up-regulated expression of salivary lysozyme and the increased lysozyme activity in S-ECC preschoolers suggests a possible connection between salivary lysozyme and oral immunity in response to early childhood dental caries.

Dental caries, Lysozyme, Saliva, Preschoolers

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