Objectives To assess a selection of host‐derived biomarkers in peri‐implant sulcus fluid (PISF) and gingival crevicular fluid (GCF) from adjacent teeth 10 years following implant placement. Material and methods Peri‐implant sulcus fluid and GCF samples obtained from the deepest sites of 504 implants and 493 adjacent teeth were analysed for levels of interleukin (IL)‐1β, matrix metalloproteinase (MMP)‐3, MMP‐8, MMP‐1, and MMP‐1 bound to tissue inhibitor of MMP (TIMP)‐1 (MMP‐1/TIMP‐1) by enzyme‐linked immunosorbent assay (ELISA) technique. Results Overall, MMP‐8 was detected in 90% of the sites. In more than 50% of the sites, IL‐1β was identified while in 30% of the sites MMP‐1, MMP‐1/TIMP‐1 and MMP‐3 were found over the detection level. Increased biomarkers levels from PISF and GCF were positively correlated (r = 0.375–0.702; P < 0.001). However, no qualitative and quantitative differences were found between PISF and GCF. The levels of MMP‐1 were negatively correlated with those of MMP‐1/TIMP‐1 at implants (r = −0.644; P < 0.001). Median MMP‐1 levels at implants were high (5.17 pg/site) in subjects with severe chronic periodontitis and low in patients with mild‐to‐moderate chronic periodontitis (0 pg/site; P = 0.026) or gingivitis (0 pg/site; P = 0.034). Levels of IL‐1β were found to be different in GCF according to the periodontal conditions (P = 0.001) with the highest level found in mild‐to‐moderate periodontitis (6.2 pg/site). Clinical attachment levels at implants demonstrated an inverse correlation with MMP‐1/TIMP‐1 (r = −0.147; P = 0.001). Conclusions Increased levels of MMP‐8 and IL‐1β in PISF or GCF may be associated with inflammation around teeth and implants while lower levels of MMP‐1/TIMP‐1 may be an indicator of disease progression around implants.