Cost-Effectiveness of Caries Prevention in Practice: A Randomized Controlled Trial.

A 2-arm parallel-group randomized controlled trial measured the cost-effectiveness of caries prevention in caries-free children aged 2 to 3 y attending general practice. The setting was 22 dental practices in Northern Ireland. Participants were centrally randomized into intervention (22,600 ppm fluoride varnish, toothbrush, a 50-mL tube of 1,450 ppm fluoride toothpaste, and standardized prevention advice) and control (advice only), both provided at 6-monthly intervals during a 3-y follow-up. The primary outcome measure was conversion from caries-free to caries-active states assessed by calibrated and blinded examiners; secondary outcome measures included decayed, missing, or filled teeth surfaces (dmfs); pain; and extraction. Cumulative costs were related to each of the trial's outcomes in a series of incremental cost effectiveness ratios (ICERs). Sensitivity analyses examined the impact of using dentist's time as measured by observation rather than that reported by the dentist. The costs of applying topical fluoride were also estimated assuming the work was undertaken by dental nurses or hygienists rather than dentists. A total of 1,248 children (624 randomized to each group) were recruited, and 1,096 (549 in the intervention group and 547 in the control group) were included in the final analyses. The mean difference in direct health care costs between groups was £107.53 (£155.74 intervention, £48.21 control, P < 0.05) per child. When all health care costs were compared, the intervention group's mean cost was £212.56 more than the control group (£987.53 intervention, £774.97 control, P < 0.05). Statistically significant differences in outcomes were only detected with respect to carious surfaces. The mean cost per carious surface avoided was estimated at £251 (95% confidence interval, £454.39-£79.52). Sensitivity analyses did not materially affect the study's findings. This trial raises concerns about the cost-effectiveness of a fluoride-based intervention delivered at the practice level in the context of a state-funded dental service (EudraCT No: 2009-010725-39; ISRCTN: ISRCTN36180119).

A Randomized Controlled Trial of Caries Prevention in Dental Practice.

We conducted a parallel group randomized controlled trial of children initially aged 2 to 3 y who were caries free, to prevent the children becoming caries active over the subsequent 36 mo. The setting was 22 dental practices in Northern Ireland, and children were randomly assigned by a clinical trials unit (CTU) (using computer-generated random numbers, with allocation concealed from the dental practice until each child was recruited) to the intervention (22,600-ppm fluoride varnish, toothbrush, 50-mL tube of 1,450 ppm fluoride toothpaste, and standardized, evidence-based prevention advice) or advice-only control at 6-monthly intervals. The primary outcome measure was conversion from caries-free to caries-active states. Secondary outcome measures were number of decayed, missing, or filled teeth (dmfs) in caries-active children, number of episodes of pain, and number of extracted teeth. Adverse reactions were recorded. Calibrated external examiners, blinded to the child's study group, assessed the status of the children at baseline and after 3 y. In total, 1,248 children (624 randomized to each group) were recruited, and 1,096 (549 intervention, 547 control) were included in the final analyses. Eighty-seven percent of intervention and 86% of control children attended every 6-mo visit ( P = 0.77). A total of 187 (34%) in the intervention group converted to caries active compared to 213 (39%) in the control group (odds ratio, 0.81; 95% confidence interval, 0.64-1.04; P = 0.11). Mean dmfs of those with caries in the intervention group was 7.2 compared to 9.6 in the control group ( P = 0.007). There was no significant difference in the number of episodes of pain between groups ( P = 0.81) or in the number of teeth extracted in caries-active children ( P = 0.95). Ten children in the intervention group had adverse reactions of a minor nature. This well-conducted trial failed to demonstrate that the intervention kept children caries free, but there was evidence that once children get caries, it slowed down its progression (EudraCT No: 2009-010725-39; ISRCTN: ISRCTN36180119).