Purpose: The aims of the present study were to determine (i) the long-term disease recurrence in intraosseous defects that had undergone an open flap debridement (OFD) procedure with or without enamel matrix derivative (EMD); and (ii) whether and to what extent clinical changes recorded on teeth treated with surgery were similar at sites involved or adjacent to the intraosseous defect. Materials and Methods: Eleven patients contributing twelve reconstructed intraosseous defects were retrospectively recruited and included for analysis. Immediately before surgery, at 12 months post-surgery and at long-term examination (6-8 years post-surgery), probing pocket depth (PPD) and clinical attachment level (CAL) were recorded at the test site (representative of the reconstructed intraosseous defect) and the control site (representative of an adjacent non-reconstructed site) of each tooth treated with surgery. Results: All patients received monthly professional maintenance up to 12 months after surgery, and every 6 months or less frequently thereafter. In test sites, CAL varied from 5.4 ± 0.8 mm at 12 months to 6.5 ± 1.0 mm at the long-term examination. PPD increased from 3.7 ± 0.4 mm at 12 months to 4.3 ± 0.6 mm at the long-term examination, the changes being not statistically significant. When PPD and CAL changes from 12 months to the long-term examination were compared between test and control sites, no significant differences were found. Conclusions: Within its limitations and considering the limited sample size, the present study indicates that (i) the attachment gain that has been achieved by means of a surgical reconstructive procedure (based on OFD with/without EMD) may be mostly maintained over a 6-8 year follow-up period; and (ii) the extent of disease recurrence, as assessed by attachment loss and pocket deepening, was similar at sites involved or adjacent to the intraosseous defect. Schlagwörter: disease progression, disease recurrence, intrabony defect, maintenance therapy, reconstructive surgery