Impact of conditioning regimens on salivary function, caries-associated microorganisms and dental caries in children after bone marrow transplantation. A 4-year longitudinal study

Salivary function, dental caries and caries-associated salivary microorganisms were investigated in children undergoing BMT during a 4-year longitudinal study, Fourteen children were conditioned with CY and TBI and 12 with CY with or without BU, Four years after BMT the mean salivary secretion rate was 1.3 +/- 0.7 ml/min in the chemotherapy group, compared to 0.7 +/- 0.5 in the TBI/CY group (P < 0.05), The mean salivary secretion rate fell from 0.9 +/- 0.5 ml/min before TBI to 0.2 +/- 0.1 after 3 months (P < 0.01), 0.3 +/- 0.3 ml/min after 6 months (P < 0.01) and 0.5 +/- 0.6, 1 year after TBI (P < 0.05), Mean reduction in stimulated salivary flow 3 months after TBI was 78% in the TBI/CY group compared to 36% in the chemotherapy group (P < 0.05), Children conditioned with chemotherapy showed an increased salivary flow compared to baseline; this was not found in TBI-treated children, suggesting that damage to the salivary glands may be permanent, Four years after BMT, children conditioned with TBI had significantly higher counts of mutans streptococci (P < 0.05) and lactobacilli (P < 0.01) compared to age-matched controls, However, the prevalence of dental caries did not differ between children conditioned with TBI, chemotherapy and healthy controls.