Protocol for Northern Ireland Caries Prevention in Practice Trial (NIC-PIP) trial: a randomised controlled trial to measure the effects and costs of a dental caries prevention regime for young children attending primary care dental services

BACKGROUND: Dental caries is a persistent public health problem with little change in the prevalence in young children over the last 20 years. Once a child contracts the disease it has a significant impact on their quality of life. There is good evidence from Cochrane reviews including trials that fluoride varnish and regular use of fluoride toothpaste can prevent caries. The Northern Ireland Caries Prevention in Practice Trial (NIC-PIP) trial will compare the costs and effects of a caries preventive package (fluoride varnish, toothpaste, toothbrush and standardised dental health education) with dental health education alone in young children. METHODS/DESIGN: A randomised controlled trial on children initially aged 2 and 3 years old who are regular attenders at the primary dental care services in Northern Ireland. Children will be recruited and randomised in dental practices. Children will be randomised to the prevention package of both fluoride varnish (twice per year for three years), fluoride toothpaste (1,450 ppm F) (supplied twice per year), a toothbrush (supplied twice a year) or not; both test and control groups receive standardised dental health education delivered by the dentist twice per year. Randomisation will be conducted by the Belfast Trust Clinical Research Support Centre ([CRSC] a Clinical Trials Unit). 1200 participants will be recruited from approximately 40 dental practices. Children will be examined for caries by independent dental examiners at baseline and will be excluded if they have caries. The independent dental examiners will examine the children again at 3 years blinded to study group. The primary end-point is whether the child develops caries (cavitation into dentine) or not over the three years. One secondary outcome is the number of carious surfaces in the primary dentition in children who experience caries. Other secondary outcomes are episodes of pain, extraction of primary teeth, other adverse events and costs which will be obtained from parental questionnaires. DISCUSSION: This is a pragmatic trial conducted in general dental practice. It tests a composite caries prevention intervention, which represents an evidence based approach advocated by current guidance from the English Department of Health which is feasible to deliver to all low risk (caries free) children in general dental practice. The trial will provide valuable information to policy makers and clinicians on the costs and effects of caries prevention delivered to young children in general dental practice. TRIAL REGISTRATION: EudraCT No: 2009 - 010725 - 39 ISRCTN: ISRCTN36180119 Ethics Reference No: 09/H1008/93: