Multimodal diagnostic evaluation of the combined efficacy of advanced-platelet rich fibrin and demineralized bone matrix of type one collagen versus their individual assessment in the management of periodontal intrabony defects - a clinico-radiographic and immunological study.

Chronic periodontitis is an infectious disease caused by bacteria in dental plaque, leading to destruction of gingiva, periodontal ligament, cementum, and alveolar bone, and progresses with phases of exacerbation and remission, affecting nearly 50% of the global population with 1.1 billion severe cases reported in 2019. Management includes non-surgical therapy such as scaling, root planing, and oral hygiene instruction to control inflammation, while surgical interventions are required for persistent deep pockets and bone loss. Platelet-rich fibrin (PRF), a second-generation autologous platelet concentrate introduced by Choukroun et al. in 2001, and its modifications like injectable PRF (i-PRF) and advanced PRF (A-PRF, introduced in 2014 using low-speed centrifugation) enhance regeneration by releasing higher amounts of growth factors, though further validation is needed. PRF combined with xenogenic bone substitute materials (XBSM), particularly bovine-derived hydroxyapatite-based xenografts which are osteoconductive but non-osteogenic, has shown superior outcomes in intrabony defect treatment with improved probing depth reduction, attachment gain, and defect fill. Periodontal disease progression is mediated by inflammation characterized by vascular changes and accumulation of leukocytes, cytokines, and interleukins, with IL-6—produced by immune cells—detected at higher levels in inflamed gingiva and gingival crevicular fluid of periodontitis patients. Against this background, the present study aims to compare the combined efficacy of A-PRF and xenografts versus their individual applications in periodontal defect regeneration through both clinical and molecular assessments.

All patients will undergo scaling, root planing and oral hygiene instructions will be given. Measurements for clinical parameters will be recorded by a single investigator. The cases will then be re-evaluated. Out of 36 intrabony defects,12 intrabony defects will be treated with a combined block of A-PRF and xenograft (colocast®) and 12 intrabony defects will be treated with A-PRF alone and the other 12 intrabony defects will be treated with the xenograft (colocast®) alone as a regenerative material.

 During surgery, 10 mL of intravenous blood will be drawn from the antecubital vein and collected in a syringe without anticoagulant. The blood sample will then be immediately centrifuged at – 1300 rpm for 8 minutes using a Remi Medico Centrifuge.

After centrifugation, the fibrin clot will be carefully removed from the tube and separated using microsurgical scissors. Advanced Platelet-rich fibrin (A-PRF) will then be obtained in the form of a membrane by gently squeezing out the fluids from the fibrin clot.

    The surgical technique will be performed under local anesthesia. The post-operative evaluation and data collection will be done at 3 and 6 months.

 The clinical parameters to be recorded are:

Soft tissue parameters

·      Pocket depth (from gingival margin to base of the pocket)

·      Clinical attachment level

Hard tissue parameters:

·      Radiographic analysis of linear bone growth  and % of bone fill.

Standardized radiographs of the defect sites will be taken using IOPAR film grids to measure the amount and density of bone fill.

 The Immonological analysis will involve measuring IL-6 levels in gingival crevicular fluid (GCF) using an ELISA kit. Approximately 3µl of GCF samples will be collected, at baseline and 6 months ,using microcapillary pipettes which will be wrapped in tin foil and placed in cryovial sealed with parafilm and stored at -80oC until analysis. The quantification will be performed with the Multiskan GoTM microplate spectrophotometer from Thermo Scientific, ensuring precise and reliable assessment of IL-6 concentration in the samples.

The samples will be processed in Central Research Laboratory, RRMCH, Bangalore.