The occurrence of peri‐implant mucositis associated with the shift of submucosal microbiome in patients with a history of periodontitis during the first two years.

Aim: To investigate the dynamic changes of peri‐implant microbiome in patients with a history of periodontitis and to construct a microbial prediction model. Materials and methods: The prospective study was performed at one month (T1), one year (T2) and two years (T3) after restoration. Clinical examinations [probing depth (PD), bleeding on probing (BOP), suppuration (SUP)], radiographic examinations and sample collection were conducted at three timepoints. Peri‐implant sulcular fluid (PISF) was collected and analysed by 16S rRNA gene sequencing. Generalized linear mixed model (GLMM) was used to identify differences. Results: Totally, 168 subjects were assessed for eligibility. Twenty‐two patients were recruited in the longitudinal study. Eventually, 67 PISF samples from 24 implants of 12 patients were collected and analysed. Peri‐implant microbiome showed increasing diversity and complexity over time. Disease‐associated genera Porphyromonas, Tannerella, Treponema and Prevotella dramatically increased from T1 to T3. The prediction model for clinical suppuration at T1 showed a high accuracy of 90%. Conclusion: The dysbiosis of peri‐implant microbiome increased with time during the two‐year observation in patients with a history of periodontitis. Genera of Porphyromonas, Tannerella, Treponema and Prevotella were biomarkers of peri‐implant mucositis. Microbiota at the early stage could predict subsequent microbial dysbiosis and clinical suppuration. [ABSTRACT FROM AUTHOR]