A systematic review featured a single RCT (n=185) comparing the effect of a 12-month vs 24-month interval between dental visits on dental caries in low-risk 3- to 5-year-old children with primary teeth and young adults, ages 16 to 20 years, with permanent teeth.1 The outcomes of caries (ie, decayed, missing, filled surfaces increment) between the 12- and 24-month visits both in younger children (mean difference [MD]= -0.90; 95% confidence interval [CI], -1.96 to 0.16) and young adults (MD= -0.86; 95% CI, -1.75 to 0.03) did not differ.
Gingivitis: Not an issue when visits were delayed in healthy adults
Another systematic review (3 RCTs; N=836) evaluated the benefits associated with scaling and polishing in the prevention of gingivitis (primary outcome measure).2 One RCT (n=207) compared scaling and polishing at 6- and 12-month intervals to no treatment for 24 months in adults with healthy dental histories. There was no difference in the percentage of index teeth with bleeding in the 6-month or 12-month treatment groups compared to the group that received no treatment for 24 months (MD= -2%; 95% CI, -10% to 6% and MD= -1%; 95% CI, -9% to 7%, respectively).
2 visits/year prevents tooth loss in high-risk patients
A retrospective cohort study (N=5117) using 16 years of data evaluated the association between one or 2 preventive dental visits per year and tooth extraction events in adults at low risk and those at high risk for progressive periodontitis.3 Those at high risk had at least one of the following risk factors: smoking, diabetes, or interleukin-1 genotype. Low-risk patients had no difference in tooth loss with one visit compared to 2 visits annually (absolute risk reduction [ARR]=2.6%; 95% CI, 0.5%-5.8%; P=.092); however, high-risk patients had fewer events with 2 annual visits (number needed to treat [NNT]=19; ARR 5.2%; 95% CI, 1.8%-8.4%; P=.002).