How do erythritol and glycine air polishing powders compare?

Based on this systematic review and network meta-analysis of nine RCTs involving 462 patients, erythritol and glycine showed no statistically significant difference across the primary outcomes of PPD, CAL, and BOP in non-surgical periodontal treatment ^[1][2]. However, in the network meta-analysis SUCRA rankings for PPD reduction, erythritol scored higher (84.1) than glycine (28.5), suggesting a probabilistic advantage for erythritol in pocket depth reduction, though this did not reach statistical significance ^[1][2].

From a physicochemical standpoint, erythritol has a smaller particle size (14 μm) compared to glycine (25–65 μm), making it less abrasive, and it exerts antimicrobial effects by altering the microstructure and metabolic profile of P. gingivalis biofilm in vitro ^[1]. Glycine is biocompatible and highly soluble, reduces subgingival P. gingivalis, A. actinomycetemcomitans, and F. nucleatum, but some studies indicate it may enhance pro-inflammatory gene expression (TNFα, IL-8, CCL2) via NF-κB activation and delay wound healing in vitro ^[1]. Both powders have been reported to have no adverse events ^[1].

The authors recommend prioritising erythritol over glycine when selecting a subgingival air-polishing powder, while noting that powder selection should also account for disease severity, patient oral hygiene habits, treatment tolerance, and the chemical properties of each powder ^[1][2]. Clinicians should interpret these findings cautiously given the small number of included RCTs and heterogeneity in study design, parameters, and follow-up duration ^[1].