Local delivery natural products to treat periodontitis: a systematic review and meta-analysis

Objectives This study aimed to answer the PICO question: in adults with periodontitis, does subgingival delivery of natural products (NP) after scaling and root planing (SRP) results in a better reduction of probing pocket depth (PPD) when compared with SRP alone or SRP plus placebo? Material and methods A search for trials was carried out in eight databases. Two independent investigators performed all steps of this review. PPD reduction, clinical attachment level (CAL) gain, gingival inflammation, and biofilm accumulation reduction were investigated. We conducted meta-analyses where data could be pooled. Results Searches yielded 4771 records, in which 27 trials fulfilled the eligibility. There was a large heterogeneity among trials ( I 2 > 0.69, χ 2 < 0.000). Only four studies were at low risk of bias. The evidence quality was very low. The effectiveness of NP was demonstrated in a follow-up of 3–6 months considering PPD reduction (8 trials: 0.72 mm [95%CI: 0.23, 1.22]) and CAL gain (5 trials: 1.07 mm [95%CI: 0.36, 1.78]). A significant reduction in periodontal inflammation favors the use of NP. The biofilm accumulation reduction effect of NP was very weak or non-significant. Conclusion Although the high risk of bias and large heterogeneity of trials impose some restrictions on the validity of effect estimate, this review indicates that adjunctive NP better reduced the PPD when compared to SRP alone or SRP plus placebo in a follow-up of 3–6 months. Clinical relevance The evidence of non-responsive patients to conventional periodontal therapy highlights the need for therapeutic alternatives to treat periodontitis.