Pocket closure and residual pockets after non-surgical periodontal therapy: A systematic review and meta-analysis

Aim: To analyse the efficacy of non-surgical therapy (NST) in terms of pocket closure (PC) and changes in percentage and number of pockets. Materials and Methods: Three databases (PubMed, EMBASE, and Scopus) were searched up to January 2020. Prospective studies with a minimum follow-up of 12 months and presenting data in terms of PC or number or percentage of pocket depths (PDs) before and after NST on systemically healthy patients were included. Random-effect meta-analyses were performed. Results: After screening 4610 titles and abstracts, 27 studies were included. Of these, 63.9% of PC was reported by one study. The percentage of PDs ≤3 mm changed from 39.06% to 64.11% with a weighted mean difference (WMD) of 26.14% (p <.001). This accounted for a relative increase of healthy sites of 64.13%. The mean percentage of PD ≥5 mm was 28.23% and 11.71% before and after treatment, respectively, with a WMD of 15.50% (p <.001). The WMD in the number of PDs ≥5 mm before and after treatment was 24.42 (p =.036). The mean number of residual PPD ≥5 after NST was 14.13. Conclusions: NST is able to eradicate the majority of the pockets. However, residual pockets after NST may remain and should be considered cautiously for further treatment planning.