Analysis of Orthodontic Appliance Association with Commensal Akkermansia muciniphila and Oral Microbial Composition Within a Dental School Saliva Biorepository

Akkermansia muciniphila (AM) is a Gram-negative commensal bacteria that has been found in both the oral cavity and gastrointestinal tract and has the ability to maintain homeostasis in the intestinal tract by inducing anti-inflammatory responses. The purpose of this study was to evaluate the presence of AM in the oral microbiome of patients with and without orthodontic appliances to determine any associations with other oral bacteria. This retrospective study of orthodontic and non-orthodontic saliva samples (n = 209) was screened by qPCR analysis for AM, Scardovia wiggsiae (SW), Selenomonas noxia (SN), Streptococcus mutans (SM), Porphyromonas gingivalis (PG), Treponema denticola (TD), and Fusobacterium nucleatum (FN). These data revealed oral microbial prevalence between 29.8% (AM) and 54.3% (SM)—with orthodontic samples revealing decreased AM prevalence (−29.5%), compared with non-orthodontic samples and corresponding increased prevalence of PG (+2.7%), TD (+13.7%), SM (+22.2%) and SN (+26.0%). AM-positive samples exhibited decreased prevalence of SN (−16.0%), SM (−1.6%), PG (−10.2%), TD (−4.2%), and FN (−14.3%). These findings may suggest that orthodontic appliances may be associated with decreased AM prevalence, which may be associated with increased prevalence of other oral pathogens.