Impact of SASP in the GCF on the Outcomes of Periodontal Regeneration

• Minimally invasive surgical procedure (Procedure): All the experimental sites underwent a minimally-invasive surgical technique (MIST) procedure under magnification (Cortellini and Tonetti 2007). The full-thickness flap was minimally raised both on the buccal and oral side, avoiding vertical releasing incisions. Granulation tissue was scraped from the bony surfaces of the defect, and the root was debrided using minicurettes/ultrasonic device and chemically treated by EDTA. Regenerative procedure was carried out using a combination of enamel matrix derivatives and bone xenograft. The flaps were then repositioned and sutured in order to obtain passive primary closure.

Primary outcomes

• Clinical attachment level change [[Time Frame: 12 months]]: Clinical attachment level will be assessed on the experimental teeth using periodontal probe (PCP 15/11.5, Hu-Friedy, Chicago, IL, USA)
• Achievement of composite outcome measure [[Time Frame: 12 months]]: Composite outcome measure (COM) will be achieved by sites with probing pocket depth < 4 mm and relevant clinical attachment gain ≥ 3 mm at the 12-month re-evaluation

Secondary outcomes

• Radiographic bone level change [[Time Frame: 12 months]]: Periapical standardized radiographs will be taken by a clinician masked to the clinical measurements using the paralleling technique and individually customized bite-blocks (RINN XCP Film Holding Instruments, Dentsply, York, USA)
• Probing pocket depth change [[Time Frame: 12 months]]: Probing depth will be assessed on the experimental teeth using periodontal probe (PCP 15/11.5, Hu-Friedy, Chicago, IL, USA)

Sex: All, ages: 18 Years to any, accepts healthy volunteers

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.