Examining the effectiveness of different dental recall strategies on maintenance of optimum oral health: the INTERVAL dental recalls randomised controlled trial

Objective To compare the clinical effectiveness of different frequencies of dental recall over a four-year period. Design A multi-centre, parallel-group, randomised controlled trial with blinded clinical outcome assessment. Participants were randomised to receive a dental check-up at six-monthly, 24-monthly or risk-based recall intervals. A two-strata trial design was used, with participants randomised within the 24-month stratum if the recruiting dentist considered them clinically suitable. Participants ineligible for 24-month recall were randomised to a risk-based or six-month recall interval. Setting UK primary dental care. Participants Practices providing NHS care and adults who had received regular dental check-ups. Main outcome measures The percentage of sites with gingival bleeding on probing, oral health-related quality of life (OHRQoL), cost-effectiveness. Results In total, 2,372 participants were recruited from 51 dental practices. Of those, 648 were eligible for the 24-month recall stratum and 1,724 participants were ineligible. There was no evidence of a significant difference in the mean percentage of sites with gingival bleeding on probing between intervention arms in any comparison. For those eligible for 24-month recall stratum: the 24-month versus six-month group had an adjusted mean difference of -0.91%, 95% CI (-5.02%, 3.20%); the 24-month group versus risk-based group had an adjusted mean difference of 0.07%, 95% CI (-3.99%, 4.12%). For the overall sample, the risk-based versus six-month adjusted mean difference was 0.78%, 95% CI (-1.17%, 2.72%). There was no evidence of a difference in OHRQoL (0-56 scale, higher score for poorer OHRQoL) between intervention arms in any comparison. For the overall sample, the risk-based versus six-month effect size was -0.35, 95% CI (-1.02, 0.32). There was no evidence of a clinically meaningful difference between the groups in any comparison in either eligibility stratum for any of the secondary clinical or patient-reported outcomes. Conclusion Over a four-year period, we found no evidence of a difference in oral health for participants allocated to a six-month or a risk-based recall interval, nor between a 24-month, six-month or risk-based recall interval for participants eligible for a 24-month recall. However, patients greatly value and are willing to pay for frequent dental check-ups

Dung removal increases under higher dung beetle functional diversity regardless of grazing intensification

Dung removal by macrofauna such as dung beetles is an important process for nutrient cycling in pasturelands. Intensification of farming practices generally reduces species and functional diversity of terrestrial invertebrates, which may negatively affect ecosystem services. Here, we investigate the effects of cattle-grazing intensification on dung removal by dung beetles in field experiments replicated in 38 pastures around the world. Within each study site, we measured dung removal in pastures managed with low- and high-intensity regimes to assess between-regime differences in dung beetle diversity and dung removal, whilst also considering climate and regional variations. The impacts of intensification were heterogeneous, either diminishing or increasing dung beetle species richness, functional diversity, and dung removal rates. The effects of beetle diversity on dung removal were more variable across sites than within sites. Dung removal increased with species richness across sites, while functional diversity consistently enhanced dung removal within sites, independently of cattle grazing intensity or climate. Our findings indicate that, despite intensified cattle stocking rates, ecosystem services related to decomposition and nutrient cycling can be maintained when a functionally diverse dung beetle community inhabits the human-modified landscape