Effect of orthodontic therapy in periodontitis and non-periodontitis patients: a systematic review with meta-analysis

Aim To answer these PICO questions: #1: In adult patients with malocclusion, what are the effects of orthodontic tooth movement (OTM) on clinical attachment level (CAL) changes in treated periodontitis patients with a healthy but reduced periodontium compared to non-periodontitis patients? #2: In adult patients with treated periodontitis and malocclusion, which is the efficacy of skeletal anchorage devices compared to conventional systems in terms of orthodontic treatment outcomes? Material and methods Seven databases were searched until June 2020 looking for randomized, non-randomized trials and case series. Mean effects (ME) and 95% confidence intervals (CIs) were calculated. Results Twenty-six studies with high risk of bias were included. PICO#1: In 26 patients without periodontitis and in 69 treated periodontitis patients, minimal changes in periodontal outcomes were reported after orthodontic therapy (p > 0.05). A significant CAL gain (mm) (ME = 3.523; 95% CI [2.353; 4.693]; p < 0.001) was observed in 214 patients when periodontal outcomes were retrieved before a combined periodontal and orthodontic therapy. PICO#2: Orthodontic variables were scarcely reported, and objective assessment of the results on orthodontic therapy was missing. Conclusions Based on a small number of low-quality studies, in non-periodontitis and in stable treated periodontitis patients, OTM had no significant impact on periodontal outcomes.