A Comparative Analysis of Differences in Salivary hBD-2 Levels and Their Correlation with Dental Caries and Unstimulated Saliva pH in Children with Primary and Permanent Dentition

<b>Background/Objectives</b>: This exploratory study aimed to investigate potential differences and associations between salivary hBD-2 levels and dental caries, as well as between unstimulated salivary pH and salivary hBD-2 levels, in children with primary and permanent dentition, aiming to profile these two dentition-development groups. <b>Materials and Methods</b>: This cross-sectional study included children with primary (<i>n</i> = 75) and permanent dentition (<i>n</i> = 78). Data were collected by surveying mothers and clinically exam ining their children. Unstimulated saliva samples of the children were collected to determine salivary pH and hBD-2 levels. Spearman's rank correlation coefficient was used to assess the correlation between the examined variables. <b>Results</b>: Children with permanent dentition had a significantly higher mean salivary hBD-2 level (<i>p</i> = 0.044), while children with primary dentition had a significantly higher mean unstimulated saliva pH (<i>p</i> < 0.001). No significant correlation was determined between salivary hBD-2 levels and dental caries, nor between unstimulated saliva pH and dental caries in either group of study participants (hBD-2: <i>p</i> = 0.515 and 0.224; pH: <i>p</i> = 0.121 and 0.061, respectively). A significant negative association between salivary hBD-2 peptide levels and unstimulated saliva pH in children with permanent dentition was revealed (<i>r_s</i> = -0.230, <i>p</i> = 0.043). <b>Conclusions</b>: Salivary hBD-2 levels were higher in children with permanent dentition, with an inverse association with unstimulated saliva pH observed only in this group. No significant correlation was found between salivary hBD-2 levels and dental caries. Further well-designed studies are needed to better understand dentition or age-related variations in salivary hBD-2 levels, their association with unstimulated salivary pH, and their potential as a caries biomarker.