Protein profile and tissue responses at newly restored implants compared to contralateral teeth over 12-months

Objectives To determine peri-implant tissue and crevicular fluid alterations in newly restored implants during their first year of function and associate them with those of contralateral teeth. Materials and Methods In ten periodontally healthy non-smokers, one newly restored implant (baseline-T0) and one corresponding tooth were followed for 12-months (T1). Oral hygiene was closely monitored during the study. Periodontal clinical indices and crevicular fluid were collected from an implant-site (PICF) and a tooth-site (GCF). Total proteomic profiles of PICF and GCF were investigated using label-free quantitative proteomics. Results Clinical recordings remained stable at 12-months on the tooth-/implant-site basis. The comparative analysis of protein enrichment between teeth and implants at T0 revealed 664 human proteins, with 93 found only in teeth and 217 exclusively in implants. Among the 354 overlapping proteins, 46 were upregulated (log ₂ FC > 1) in teeth, while 61 in implants. At T1, 569 human proteins were exclusively identified, with 67 found only in teeth and 193 exclusively in implants. Of the 309 overlapping proteins, 22 were upregulated in teeth, while 48 were in implants. The over-representation enrichment analysis identified "interferon-alpha response" and "allograft rejection" pathways, as significantly regulated categories at T0, with the latter being over-represented at T1. Conclusions Maturation of the peri-implant tissues was evident during the study. Proteins expressed in crevicular fluid reflected unique patterns between implants and teeth that are worth studying. Clinical Relevance: Different proteomic patterns were observed at the implant-site compared to the contralateral tooth-site towards inflammatory processes that prevail within otherwise clinically healthy peri-implant tissues. Clinical trial registration number : ClinicalTrials.gov ID: NCT06379022