Abstract

Background. JIA is an autoimmune systemic disease that affects dental health, particularly in the context of caries. Several studies show statistically significant differences in the concentration of the main inorganic elements of oral fluid, pH values, and the rate of its excretion, but the results of various studies are complementary. This makes it relevant to restore further the characteristics of the creation of biological fluid, which will contribute to understanding the characteristics of risk factors for caries and facilitate the development of personalized prevention programs. Aim: to determine the levels of pH, calcium, phosphorus, and calcium/phosphorus ratio in oral fluid and the rate of its excretion in children and adolescents with JIA, depending on the disease subtype, basic medication, and the activity of the carious process. Materials and methods. The study was conducted in the State Institution "Institute of Child and Adolescent Health" and included 80 adolescent children aged 10 to 17 years with a diagnosis of JIA. The control group consisted of 20 children without general somatic pathology. Analysis of oral fluid for calcium, phosphorus, Ca/P content, pH and rate of its excretion was carried out in groups according to the distribution: the first distribution was based on the presence or absence of JIA (n = 80 and n = 20, respectively); the second distribution was based on basic medical support - patients receiving methotrexate (MTX) ≤ 15 mg (n = 43), MTX > 15 mg (n = 18), adalimumab (n = 19) and the control group (n = 20); the third distribution was based on the subtype of JIA - polyarticular rheumatoid factor positive (RF+) (n=29), polyarticular RF- (n=10), enthesitis-associated (n=12), undifferentiated (n=5), oligoarticular (n=24) variants of JIA and healthy controls (n=20); the fourth division was made among consumers with JIA, based on the WHO classification of caries risk assessment − very low (n=10), low (n=11), standard (n=20), high (n=20) and very high (n=19). Results. In this research, no statistically significant differences were found in the concentrations of calcium and phosphorus, Ca/P ratio in the saliva of patients with JIA compared to healthy controls. Children with JIA in this study had slightly higher pH compared to controls (7.50 (7.50; 8.00) and 7.00 (7.00; 7.25) respectively). JIA patients were shown to have an average 22% lower oral fluid excretion rate compared to controls. The data obtained indicate that patients treated with methotrexate demonstrate an alkaline oral fluid reaction compared to a neutral in the healthy control group. A dosedependent effect of methotrexate concentration on the oral fluid excretion rate was demonstrated - patients treated with MTX at a dosage of > 15 mg had a 1.5-fold higher oral fluid excretion rate compared to those taking MTX at lower doses. JIA subtype affects pH following the trend described above for use with JIA as a whole. This study did not confirm the presence of significant differences in the analyzed indicators when used with JIA depending on their belonging to the caries risk group according to WHO. Conclusion. The findings identified in the research can be used as the basis for a comprehensive program of caries risk reduction in adolescents with JIA and give vectors for providing recommendations by dentists working with this category of patients