The standard of care for regeneration of lost periodontal tissue from disease at contained defect sites non-responding to non-surgical periodontal therapy is periodontal regenerative surgery. The classical practice of periodontal regeneration involves an open flap surgical approach with the the application of biologics (Enamel matrix derivatives EMD) and biomaterials after root surface debridement. EMD, derived from porcine, has been well documented for its safety and efficacy and widely used in periodontal regeneration. There is some evidence demonstrating promising treatment outcome of the flapless application of periodontal regenerative biologics after nonsurgical subgingival debridement. Endoscopic-Assisted Subgingival Debridement EASD with a high magnification up to 40X has been shown to be a non-inferior nonsurgical treatment alternative to open flap debridement with shorter operation times and better early wound healing. We hypothesize that EASD could be integrated into flapless periodontal regeneration to improve clinical performance, patient comfort and acceptance to regenerative procedures. Hence, the focus of this study is to investigate whether flapless application of EMD as an adjunct to EASD can achieve non-inferior clinical results compared to classical open-flap periodontal regeneration using Papilla Preservation Surgical Technique PPT in managing residual periodontal intrabony defects 1 year after intervention. Half of the patients will be randomized to recieve EASD and flapless regneration with EMD, while the other half of the patient will receive classical regeneration with PPT and EMD.

Inclusion Criteria:

• Stage III - Stage IV Periodontitis patients, 3-4 months after completing steps I & II periodontal therapy.
• At least 1 tooth presented with 1 site with >5mm residual PPD and ≥6mm CAL, with ≥3mm intra-osseous defect presented involving predominantly the interdental space of the tooth and presented on paralleling periapical radiographs and/or CBCT.
• Presence of a periodontally stable tooth with PPD≤3mm immediate adjacent to the intra-bony defect of the investigated tooth
• Good Oral Hygiene, with Full Mouth Plaque Score ≤25% at baseline and with good plaque control at proposed surgical field.

Exclusion Criteria:

• Pre-study period

  • Any systemic condition which prevents following the study protocol;
  • Any systemic condition which may affect healing outcomes of patients, e.g. uncontrolled or poorly controlled diabetes, unstable or life-threatening conditions or those requiring antibiotic prophylaxis;
  • Patients under long-term analgesic medication;
  • Current smokers;
  • Self-reported pregnancy;
  • Systemic antimicrobial therapy within 3 months;
  • Teeth that concurrently present with a buccal and a lingual intrabony defect component;
  • Tooth with hopeless prognosis or questionable prognosis associated with endodontic lesions, or subgingival restorations that preclude clinical measurements, or excessive uncontrolled mobility;
  • Any factors which prohibit regular performance of plaque control around surgical sites;
  • Inadeduate oral hygiene with full mouth plaque score >25%
  • Furcation involved surfaces

• During study period -Non-compliance with study protocol

There is concern that individual participant data sharing may violate data ownership policy of the institute. Information sheet and consent form approved by local IRB did not explicitly permit data sharing beyond the scope of the current study. As such, sharing IPD could potentially infringe upon the rights and expectations of our participants, which we are committed to safeguarding.