DISRUPTION OF ORAL FLUID ACID-BASE HOMEOSTASIS IN INTERNALLY DISPLACED CHILDREN AGED 6–13 YEARS WITH VARYING STATES OF DENTAL HARD TISSUES

Abstract

Introduction. Military aggression and forced internal displacement have become powerful stress factors that have radically changed the living conditions of Ukrainian children. Prolonged distress and social maladaptation inevitably affect the physiological state of the body, particularly the local immune system. Since unstimulated oral fluid is a key regulator of caries resistance, studying its acid-base balance in displaced children is of critical importance for predicting and preventing the aggressive development of dental caries during the mixed dentition period. Objective. The aim of this study was to establish the features of oral fluid acid-base homeostasis disruptions in internally displaced children aged 6-13 years, depending on the state of their dental hard tissues, through a comparative approach. Materials and methods. An open comparative cross-sectional study was conducted involving 375 schoolchildren. The main group consisted of 149 internally displaced children (IDPs), while the comparative group included 226 permanent residents of the Ternopil region. The sample was stratified by age (6-9 and 10-13 years) and the clinical state of dental hard tissues (intact teeth / dental caries). Rapid assessment of the pH level of unstimulated oral fluid was performed ex vivo using “Hydrion 9800” test systems. Buffer capacity was determined using B. Krasse’s acid titration method. Data analysis was performed utilizing parametric and nonparametric statistical methods. Results and discussions. A significant deterioration of preclinical caries resistance markers was established in IDP children. A pronounced shift of the oral fluid pH towards the acidic side was recorded: an acidic environment was diagnosed in the vast majority of displaced children with caries in both age groups, which is 3.5-5.7 times more frequent compared to local residents, p<0.01. In IDP children aged 10-13 years with dental caries, a profound depletion of salivary defense mechanisms occurred: normal buffer capacity was not detected in this subgroup at all, whereas its critically low level was recorded in 32.26 % of cases, which is almost three times higher than the control group parameters, p<0.01. Conclusion. It has been proven that forced internal displacement causes profound disruptions of oral fluid acid-base homeostasis in children aged 6-13 years. Compared to local residents, a significantly persistent acidification of saliva and a critical depletion of its buffer capacity are recorded in IDP children, which are most pronounced in the presence of dental caries. The identified loss of natural caries resistance justifies the urgent need to adapt enhanced individualized treatment and preventive protocols for this vulnerable cohort.