Recall intervals for oral health in primary care patients: a Cochrane review

BACKGROUND There is ongoing debate about the frequency with which patients should attend for a dental checkup and the effects on oral health of the interval between checkups. Recommendations regarding optimal recall intervals vary between countries and dental healthcare systems, but 6-month dental check-ups have traditionally been advocated by general dental practitioners in many high-income countries. This review updates a version first published in 2005, and updated in 2007 and 2013. OBJECTIVES To determine the optimal recall interval of dental check-up for oral health in a primary care setting. SEARCH METHODS Cochrane Oral Health's Information Specialist searched the following databases (to 17 January 2020): Cochrane Oral Health's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL; in the Cochrane Library, 2019, Issue 12), MEDLINE Ovid, and Embase Ovid. We also searched the US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform for ongoing trials. We placed no restrictions on the language or date of publication when searching. SELECTION CRITERIA Randomized controlled trials (RCTs) assessing the effects of different dental recall intervals in a primary care setting. MAIN RESULTS We included two studies with data from 1736 participants. One study was conducted in a public dental service clinic in Norway and involved participants under 20 years of age who were regular attenders at dental appointments. It compared 12-month with 24-month recall intervals and measured outcomes at two years. The other study was conducted in UK general dental practices and involved adults who were regular attenders, which was defined as having attended the dentist at least once in the previous two years. It compared the effects of 6-month, 24-month and risk-based recall intervals, and measured outcomes at four years. The main outcomes we considered were dental caries, gingival bleeding and oral-health-related quality of life. Neither study measured other potential adverse effects. Due to the very low certainty of evidence from one trial, it is unclear if there is an important difference in caries experience between assignment to a 24-month or a 12-month recall. For 3- to 5-year-olds with primary teeth, the mean difference (MD) in dmfs (decayed, missing, and filled tooth surfaces) increment was 0.90. For 16- to 20-year-olds with permanent teeth, the MD in DMFS increment was 0.86. The trial did not assess other clinical outcomes of relevance to this review. We found high-certainty evidence from one trial of adults that there is little to no difference between risk-based and 6-month recall intervals for the outcomes: number of tooth surfaces with any caries (ICDAS 1 to 6); proportion of sites with gingival bleeding; oral-health-related quality of life. There is probably little to no difference in the prevalence of moderate to extensive caries (ICDAS 3 to 6) between the groups. We found moderate-certainty evidence from one trial of adults that there is probably little to no difference between 24-month and 6-month recall intervals for the outcomes: number of tooth surfaces with any caries; percentage of sites with gingival bleeding. There may be little to no difference between the groups in the prevalence of moderate to extensive caries. We found high-certainty evidence that there is little to no difference in oral-health-related quality of life between the groups. We found moderate-certainty evidence from one trial of adults that there is probably little to no difference between risk-based and 24-month recall intervals for the outcomes: prevalence of moderate to extensive caries; number of tooth surfaces with any caries. We found high-certainty evidence that there is no important difference between the groups in the percentage of sites with gingival bleeding; or in oral-health-related quality of life. AUTHORS' CONCLUSIONS Whether adults see their dentist for a check-up every 6 months or at personalised intervals based on their dentist's assessment of their risk of dental disease does not affect tooth decay, gum disease, or quality of life. Longer intervals (up to 24 months) between checkups may not negatively affect these outcomes. Currently, there is not enough reliable evidence available about how often children and adolescents should see their dentist for a check-up. For adults attending dental checkups in primary care settings, there is little to no difference between risk-based and 6-month recall intervals in the number of tooth surfaces with any caries, gingival bleeding and oral-health-related quality of life over a 4-year period (high certainty evidence). There is probably little to no difference between the recall strategies in the prevalence of moderate to extensive caries (moderate-certainty evidence). When comparing 24-month with either 6-month or risk-based recall intervals for adults, there is moderate- to high-certainty evidence that there is little to no difference in the number of tooth surfaces with any caries, gingival bleeding and oral-health-related quality of life over a 4-year period. The available evidence on recall intervals between dental checkups for children and adolescents is uncertain. The two trials we included in the review did not assess adverse effects of different recall strategies.