Caries experience of paediatric oncology patients in Hong Kong

Objectives: To study the caries experience of paediatric oncology patients in Hong Kong. Methods: Cancer patients aged below 19 receiving chemotherapy in Queen Mary Hospital, Hong Kong were invited to participate in this study. Ethics approval (IRB-UW-10-294) and parental consent were sought. A parental questionnaire was used to study the oral hygiene practices and socio-demographic backgrounds of the children. Clinical examination was performed to study the caries status of primary and permanent teeth using the decayed, missing and filled teeth index (dmft/DMFT). Results: Sixty nine paediatric oncology patients with a mean (±SD) age of 9.2 ±5.0 years were enrolled to this study. Among them, 43 (62%) had caries experience and their mean dmft and DMFT were 1.36 and 2.87, respectively. Higher caries experience was found on patients who were born in Mainland China (p = 0.019), had completed active chemotherapy (p = 0.042), and whose parents had lower educational level (p = 0.043). These results might be explained by the following postulations: 1) Patients who were born in Mainland China probably did not benefit from water fluoridation; 2) Patients who completed chemotherapy on average underwent longer period of therapy which might prevent them from receiving optimal dental care; 3) Parents with low educational level might not able to deliver appropriate oral hygiene practice to their children. Conclusions: In our study, a significant proportion of paediatric oncology patients in Hong Kong experienced various degrees of dental caries. Such caries experience was associated with patients' demographic backgrounds and duration of cancer treatments.