Intra-oral Comparison Of Peri-implant Mucositis And Gingivitis Microbiota

Abstract

Objectives: To characterize and compare the supra-gingival/supra-mucosal and subgingival/sub-mucosal microbiota from diseased periodontal and peri-implant niches within individuals presenting with both gingivitis and peri-implant mucositis. Methods: 22 Chinese subjects were recruited with informed consent. Each subject carried at least one implant with peri-implant mucositis and one tooth with gingivitis. Supra-gingival/supra-mucosal and subgingival/sub-mucosal plaques were sampled from diseased implant/tooth sites in each subject. Samples (n=198) were characterized by 16S rRNA gene amplicon sequencing (V3-V4) using the Illumina MiSeq PE300 system. Sequence data were analyzed using QIIME and other bioinformatics and statistical approaches. Results: A total of 3,911,219 quality-filtered reads were assigned to 2,418 operational taxonomic units (OTUs; 97% similarity cut-off). Bacteria from 11 phyla comprising 118 genera were identified. Approximately half of the OTUs (1,705) were detected in all four clinical sites. Diversity analyses based on the species richness estimates, observed OTUs and phylogenetic diversity revealed no statistically-significant differences between the microbiota present within the supra-gingival，supra-mucosal, subgingival and sub-mucosal niches. Further analyses of the relative abundances of individual species revealed significant differences (p<0.05) in 36 species from the supra-gingival/supra-mucosal niches; and 43 species from the subgingival/sub-mucosal niches between teeth and implants. Notably Veillonella dispar, Corynebacterium matruchotii, Corynebacterium durum, Selenomonas noxia and Capnocytophaga sp. HOT336 were all more abundant in teeth than in implants in both the supra- and sub-gingival/mucosal fractions; whilst Neisseria oralis, Granulicatella elegans, Aggregatibacter sp. HOT898 and Ottowia sp. HOT894 were significantly less abundant in teeth. Conclusions: The bacterial microbiota within gingivitis and peri-implant mucositis tooth/implant sites in the same individual share high levels of overall similarity. We speculate that differences in bacterial taxa present at diseased implant versus tooth niches primarily reflect differences in the host physiology and histology at the respective implant/tooth sites.