Objectives: To test the impact of clinical inflammation and molecular expression profile (senescence-associated secretory phenotype; SASP) in the gingival crevicular fluid (GCF) on the outcomes of minimally-invasive periodontal regeneration in intra-bony defects.

Methods: Sites associated with intrabony defects ≥ 3 mm requiring periodontal regeneration through minimally-invasive surgical technique were included. Pre-operatively, GCF was sampled for inflammatory biomarker analysis related to SASP [interleukin (IL)-1β, IL-6 and IL-12; matrix-metalloproteinases (MMP)-8 and -9]. Correlation analyses and logistic regression models were performed to assess the impact of predictors on clinical and radiographic outcomes.

Inclusion criteria comprised:

1) diagnosis of stage III or IV periodontitis (Papapanou et al. 2018b); 2) full-mouth plaque score (FMPS) and full-mouth bleeding score (FMBS) of <15%; 3) completion of steps I-II of periodontal treatment at least 2 months priorly; 4) tooth with residual PPD ≥ 6 mm, BoP+, and a radiographic intrabony component ≥ 3 mm, lacking furcation involvement (Aimetti et al. 2023), considered suitable for a minimally invasive procedure (Cortellini and Tonetti 2007) (Fig. 1A).

Exclusion criteria encompassed:

1) age < 18 years; 2) current smokers; 3) contraindications to surgery; 4) systemic diseases that could impact periodontal healing; 5) pregnancy and lactation; 6) a history of periodontal surgery at the experimental teeth.

Consecutive patients with a diagnosis of stage III or IV periodontitis who had undergone steps I-II of periodontal therapy were considered for inclusion.