This systematic review, and its two predecessors published in 2005 and 2007, aimed to establish from existing evidence, the beneficial and harmful effects of different recall intervals for patients seen in primary dental care. This research question has high significance for policy-makers, public health practitioners and clinicians in primary dental care setings around the world. Yet, despite the importance of the topic, this review included only one RCT, which was assessed to be of very low quality.

The included RCT, which was reported in 1992, was conducted in one clinic in Norway with a sample size of 185 patients although no sample size calculation was provided. The participants (children and adults) included in the RCT were deemed to be of low risk of dental diseases and had previously received regular dental care including clinical prevention. These participants were followed up after 24 months based on clinical and cost outcomes with no patient-centred outcomes considered.

The review judged the RCT to be of very low quality due to the lack of blinding and unclear methods of sequence generation and allocation concealment. On a more positive note the systematic review also identified, via trials registers, an ongoing RCT ‘INTERVAL’ which aims to address the paucity and lack of quality of evidence on this topic. INTERVAL is a multicentre RCT, funded by the National Institute for Health Research, being conducted with dentate adults in the UK.

This trial, based on a sample size calculation, aims to follow 1735 patients for four years and to compare a six-monthly recall interval, risk-based recall and a 24-month recall interval. The outcome measures included are caries, plaque, quality of life, patient satisfaction, anxiety and oral health-related knowledge, attitudes and behaviours, with examiners blinded to the intervention. The RCT is due to end in 2017, which gives hope that when this systematic review is next updated there will be sufficient evidence to make conclusions about the most beneficial interval for dental check-ups in primary dental care.

Practice point

  • There is insufficient evidence to support or refute the need for six-monthly dental check-ups.