Аssociation between incidence of caries of temporary teeth and pathology of the musculoskeletal system in preschool children, considering biochemical markers of connective tissue metabolism

The aim is study biochemical markers of connective tissue metabolism in children with musculoskeletal disorders and their association with dental caries of temporary teeth. There were examined 232 children at the age of 5 (202 children with musculoskeletal disorders and 30 conditionally healthy children without somatic pathology). Among children with musculoskeletal disorders 68 (33.66%) had flat feet, 59 (29.21%) – postural impairment and 75 (37.13%) – combined pathology of the musculoskeletal sestem. For further research, the children were divided into three groups, 30 people in each. Group І included children with pathology of the musculoskeletal system, dental caries, without oxyproline in urine; group ІІ – with pathology of the musculoskeletal system, dental caries and oxyproline in urine; group ІІІ – with dental caries and without oxyproline in urine. Urinary excretion of glycosaminoglycans using a nephelometric test with cetylpyridinium chloride was determined. The concentration of creatinine in urine was measured in units of weight in the formation of a chromogenic complex of a solution of picric acid with creatinine in an alkaline medium. Dental status was assessed in terms of caries prevalence, deft index and severity of dental caries. The prevalence of caries of temporary teeth in 5-years old children with musculoskeletal disorders was on average 90.6±2.05%, deft index ─ 6.62±0.20, being significantly higher than in children without somatic pathology (respectively 70.83±4.45% and 5.15±0.34, р<0.001). Oxyprolin was detected only in the urine of children with combined pathology of musculoskeletal system (on average 3.53±0.11 units). The excretion rates of glycosaminoglycans in children with pathology of the musculoskeletal system, dental caries and oxyproline in urine (gr.ІІ) were two times higher than the reference range (415.37±15,09 CPCh units / 1 g creatinine, р<0.001). In the absence of oxyproline in urine, both in somatically healthy children (gr. ІІІ) and in children with pathology of the musculoskeletal system (gr. І), the levels of excretion of glycosoaminoglycans were within the reference range (respectively 198.83±10.71 and 203.87±12.52 CPCh units / 1 g creatinine. The levels of daily excretion of creatinine were within the normal range in children of gr. ІІІ (1.17±0.13 g/day; in children of gr. І they were 2.85 times lower (0.41±0.05 g/day, p<0.001); in children of gr. ІІ – 6.5 times lower (0.18±0.02 g/day р<0.001). In children of gr. ІІ, a negative correlation was found between the levels of creatinine and oxyproline (τ= -0.68, p<0.05). The absence of oxyproline in the urine of children of gr. І and ІІІ indicates the absence of collagen decay in their bodies. In children with pathology of the musculoskeletal system against the background of undifferentiated connective tissue dysplasia (gr. ІІ), a strong, positive correlation was found between the deft index and levels of urinary excretion of oxyproline (τ= +0.77, p<0.05) and glycosaminoglycans (τ= +0.90, p<0.05), which indicates that the development of dental caries depends on the severity of the pathology of the musculoskeletal system.