Bleeding on Probing as a Predictor of Peri-Implant Bone Loss During Supportive Care: A Prospective Cohort Study

A study was made to assess the diagnostic and predictive value of bleeding on probing (BoP) and the modified Bleeding Index (mBI) for identifying progressive peri-implant bone loss over a 24-month period in patients enrolled in supportive peri-implant care.

A prospective cohort study was carried out of 59 patients with screw-retained implant-supported prostheses followed-up on for 24 months. Clinical parameters, including BoP, mBI, probing depth and plaque index, were recorded at six sites per implant across five follow-up visits. Progressive peri-implant bone loss was defined as ≥ 0.5 mm of marginal bone loss as assessed radiographically. The longitudinal diagnostic performance of the bleeding indices was evaluated using sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and receiver operating characteristic (ROC) analyses.

After 24 months, 9 of 59 implants (15.3%) demonstrated progressive bone loss. Both BoP and mBI showed high sensitivity (88.9%-100%) but low specificity (0%-26%) for detecting bone loss. PPV was low (16%-18%), whereas NPV remained high (91%-100%). Recurrent low-grade bleeding (mBI = 1) observed across multiple visits was more strongly associated with progressive bone loss than isolated episodes of severe bleeding. Consistent absence of bleeding was associated with peri-implant stability.

In patients receiving supportive peri-implant care, the absence of bleeding is a reliable indicator of peri-implant health. While bleeding assessed at a single timepoint has limited specificity, longitudinal patterns of mild bleeding are of greater value in predicting disease progression, highlighting the importance of regular monitoring and of standardized clinical assessment protocols. This prospective cohort study was not registered prior to participant recruitment and randomization.