What is the best mechanical device to clean the teeth in periodontal maintenance patients?

Aim This study evaluates the available clinical evidence with regards to the effectiveness of mechanical oral hygiene devices in patients who are in periodontal maintenance.Data sources A structured online search was conducted in PubMed/Medline, Cochrane Central Register of Controlled Trials (CENTRAL) and Embase. All the databases were explored from initiation to October 2019. Reference lists of all the included studies were hand-searched as well.Study selection Randomised clinical trials or controlled clinical trials were included in this systematic review if the participants were adult patients (≥18 years) in the maintenance phase of treatment with no systemic disorder. The scope of included studies was to assess the effects of manual toothbrushes (MTBs) and powered toothbrushes (PTBs) or interdental brushes (IDBs) on dental plaque removal and other parameters of periodontitis and gingivitis. These parameters were as follows: plaque index score (PI), bleeding on probing, clinical attachment level (CAL), gingival index (GI), probing pocket depth (PPD), gingival index (GI) and gingival recession (REC).Data extraction and synthesis The Cochrane Handbook for Systematic Reviews of Interventions (2011) and the recommendations for strengthening the reporting of systematic reviews and meta-analyses (PRISMA) were both applied to extract data (with regards to population, intervention, comparison and outcomes) in this systematic review. A network meta-analysis (NMA) was performed to compare (either directly or indirectly) the studies that shared (at least) a common treatment. Treatments were then ranked using frequentist weighted least squares method. This was done based on the standardised mean difference of end plaque scores for each oral hygiene device. Finally, the authors provided a clinical significance assessment of study results using distribution-based methods.Results In the 16 included trials, 17 comparisons were selected to be assessed. In comparisons between PTBs and MTBs, 80% of them found no difference with respect to improving clinical parameters (four out of five). When adjunctive effect of an oral irrigator (OI) in addition to regular hygiene was evaluated, 66% (two out of three) of comparisons showed a positive significant effect on the GI, bleeding index scores and PPD in favour of using an OI. In 50% of comparisons (two out of four) concerning PI reduction, IDBs showed significantly better results than dental floss. This finding was endorsed by the authors' clinical significance assessment. Indirect results of the NMA ranked the cylindrical and conical IDBs as the best oral hygiene devices (compared to MTBs) in removing interdental plaque.Conclusions Considering the dearth of evidence that met the inclusion criteria for each oral hygiene device and the low certainty of the resultant findings, no definite conclusion could be drawn to recommend any device as the best option to use in periodontal maintenance patients. Yet, according to indirect evidence, it was found that IDBs, as adjuvants to tooth brushing, could significantly improve PI reduction compared with merely using MTBs.