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

The role of income and frequency of dental visits in the relationship between dental sealant use and resin fillings after extended coverage: a retrospective cohort study

BACKGROUND

Prevention and treatment services use is closely associated with socioeconomic factors, such as income. This study aimed to investigate the relationship between implementing the sealant program and resin fillings restoration and to explore the role of income and frequency of dental visits in this relationship.

METHODS

This retrospective cohort study used the cohort database from the National Health Information Database of the National Health Insurance Service. The study population comprised 494,731 children born in 2007. A logistic regression model for the experience of resin fillings and a linear regression model for weighted utilization of them were used to identify the independent effects of dental sealants, income, and frequency of dental visits. All analyses were conducted using the SAS Enterprise Guide version 7.1 (SAS Institute Inc., Cary, NC, USA).

RESULTS

The ratio based on income level was almost proportional in all groups except the medical aid group, which had a rate as high as that of the wealthier group. Children without sealants were 1.05 times more likely to have resin fillings than others after adjusting for income level and frequency of visiting dental clinics in the final model. However, an opposite relationship between sealant experiences and resin fillings was observed in the previous model without dental visits. The gap in the weighted resin filling scores according to socioeconomic variables showed a similar tendency.

CONCLUSIONS

Income and frequency of dental visits might be confounding factors for the relationship between dental sealant and resin fillings. It is necessary to consider the complex relationship between socioeconomic indicators and service use while studying oral health inequality.

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

BACKGROUND

Dental caries is the most common disease of childhood. The NHS guidelines promote preventative care in dental practices, particularly for young children. However, the cost-effectiveness of this policy has not been established.

OBJECTIVE

To measure the effects and costs of a composite fluoride intervention designed to prevent caries in young children attending dental services.

DESIGN

The study was a two-arm, parallel-group, randomised controlled trial, with an allocation ratio of 1 : 1. Randomisation was by clinical trials unit, using randomised permuted blocks. Children/families were not blinded; however, outcome assessment was blinded to group assessment.

SETTING

The study took place in 22 NHS dental practices in Northern Ireland, UK.

PARTICIPANTS

The study participants were children aged 2-3 years, who were caries free at baseline.

INTERVENTIONS

The intervention was composite in nature, comprising a varnish containing 22,600 parts per million (p.p.m.) fluoride, a toothbrush and a 50-ml tube of toothpaste containing 1450 p.p.m. fluoride; plus standardised, evidence-based prevention advice provided at 6-monthly intervals over 3 years. The control group received the prevention advice alone.

MAIN OUTCOME MEASURES

The primary outcome measure was conversion from caries-free to caries-active states. Secondary outcome measures were the number of decayed, missing or filled tooth surfaces in primary dentition (dmfs) in caries-active children, the number of episodes of pain, the number of extracted teeth and the costs of care. Adverse reactions (ARs) were recorded.

RESULTS

A total of 1248 children (624 randomised to each group) were recruited and 1096 (549 in the intervention group and 547 in the control group) were included in the final analyses. A total of 87% of the intervention children and 85% of control children attended every 6-month visit (p = 0.77). In total, 187 (34%) children in the intervention group converted to caries active, compared with 213 (39%) in the control group [odds ratio (OR) 0.81, 95% confidence interval (CI) 0.64 to 1.04; p = 0.11]. The mean number of tooth surfaces affected by caries was 7.2 in the intervention group, compared with 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). However, 164 out of the total of 400 (41%) children who converted to caries active reported toothache, compared with 62 out of 696 (9%) caries-free children (OR 7.1 95% CI 5.1 to 9.9; p < 0.001). There was no statistically significant difference in the number of teeth extracted in caries-active children (p = 0.95). Ten children in the intervention group had ARs of a minor nature. The average direct dental care cost was £155.74 for the intervention group and £48.21 for the control group over 3 years (p < 0.05). The mean cost per carious surface avoided over the 3 years was estimated at £251.00.

LIMITATIONS

The usual limitations of a trial such as generalisability and understanding the underlying reasons for the outcomes apply. There is no mean willingness-to-pay threshold available to enable assessment of value for money.

CONCLUSIONS

A statistically significant effect could not be demonstrated for the primary outcome. Once caries develop, pain is likely. There was a statistically significant difference in dmfs in caries-active children in favour of the intervention. Although adequately powered, the effect size of the intervention was small and of questionable clinical and economic benefit.

FUTURE WORK

Future work should assess the caries prevention effects of interventions to reduce sugar consumption at the population and individual levels. Interventions designed to arrest the disease once it is established need to be developed and tested in practice.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN36180119 and EudraCT 2009-010725-39.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 71. See the NIHR Journals Library website for further project information.

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).

Effects of mothers involved in dental health program for their children

PURPOSE

The purpose of this study was to identify the effects of mothers' involvement in a dental health program for their elementary school children.

METHODS

This study was a non-equivalent control group pre-post test design in which knowledge and behaviors related to dental health, perceived benefits and barriers, self-efficacy and plaque control scores were compared between the experimental group (n=26) for whom the dental health program included the direct involvement of the mothers, and the control group (n=24) for whom knowledge related to dental health was provided through brochures.

RESULTS

Scores for the experimental group in which the mothers were involved in the dental health program were significantly higher for knowledge, behaviors in dental health, self-efficacy and plaque control compared to the control group.

CONCLUSION

Results of this study suggest that mothers involvement in the dental health program is effective in reinforcing dental health enhancing behavior in elementary school children.

Fluoride varnish was effective at reducing caries on high caries risk school children in rural Brazil

DESIGN

Placebo controlled randomised controlled trial (RCT).

INTERVENTION

Recruited children were randomly assigned to either a treatment (5% NaF varnish, n = 198) or a control group (placebo, n = 181). Data on oral health habits and socio-demographic characteristics was collected from the children by trained interviewers. Diet information was collected using a seven day food frequency diary. Caries was assessed using the International Caries Detection and Assessment System (ICDAS).

OUTCOME MEASURE

The main outcome was decayed and filled surfaces (DFS) increment at 12 months.

RESULTS

Two hundred and ten (55.4%) children having one or two applications of fluoride varnish or placebo were available for follow-up at 12 months. At the baseline examination, the children in the treatment and control groups presented with on average 6.2 and 5.6 DFS, respectively (P < 0.001). At 12 months, the children in the varnish group showed significantly lower DFS increments than did children in the control group (10.8 versus 13.3; P < 0.007), with a preventive fraction (PF) of 40% (95% CI: 34.3-45.7%; P < 0.0001).

CONCLUSIONS

The results of this study suggest that applications of 5% NaF varnish can be recommended as a public health measure for reducing caries incidence in this high-caries-risk population.