Comparative Clinical & Radiographic Evaluation of Autologous Advanced Platelet Rich Fibrin (A-PRF+) with Bioactive Glass (PerioGlas®) & Autologous Advanced Platelet Rich Fibrin (A-PRF+) with Demineralized Freeze Dried Bone Allograft (DFDBA) in the Treatment of Intrabony Defects in Chronic Periodontitis Patients- A Randomized Clinical Trial

Periodontal disease leaves a historical record of the damage to periodontium in the form of periodontal attachment and bone loss. In teeth in which continued function requires additional periodontal support, optimal treatment involves not only controlling periodontal infection, but also regeneration of the lost periodontium.

Among the plethora of regenerative modalities, bone grafts and their synthetic substitutes have been used in an attempt to gain their therapeutic endpoint; the use of which dates back to Hegedes in 1923.

Since then a number of techniques and materials have been used for regeneration. Newer ceramic alloplast like bioactive glass has shown the ability to help bone regeneration and clinical insertion gain, with better results than other materials available. Bioactive glasses are a group of surface reactive glass-ceramics composed entirely of elements naturally occurring in the body (silica, calcium, phosphorous, oxygen, and sodium). It is the formation of a biologically active hydrated calcium phosphate layer at the surface of the bioactive glass which plays a key role in the formation of the bone/graft bond. [1]

 Alloplasts, may be an effective alternative to allograft and xenografts as there is no risk of disease transmission and the supply is unlimited.

The bioactive glass enhances osteogenesis due to its properties of adsorption and concentrations of proteins that are utilized by osteoblast in order to form a mineralized extracellular matrix.[2]

 Over the past several decades, platelet concentrates (PCs) obtained from autogenous blood extraction have emerged as potential regenerative biomaterials, such as platelet-rich plasma (PRP) and plasma rich in growth factors (PRGF).

 In 2001, Choukroun et al introduced the second PC generation –platelet-rich fibrin (PRF), which induces a significant release of cytokines including platelet derived growth factor (PDGF), transforming growth factor (TGF)-β and vascular endothelial growth factor (VEGF) within its three-dimensional fibrin meshes.  Since then, PRF has been extensively utilized in dentistry for a variety of procedures demonstrating its effectiveness for tissue regeneration.

In 2014, by decreasing centrifugation speeds from 2700 rpm (750g) to 1300 rpm (200g), a better formulation of PRF was created with a higher number of leukocytes more evenly distributed throughout the softer clot.

 This new formulation of PRF was given the working name advanced PRF (A-PRF). Ongoing studies have further confirmed that with slower spinning protocols, A-PRF favours a higher growth factors release than prototypical PRF which in turn may directly influence tissue regeneration by increasing fibroblast migration, proliferation and collagen mRNA levels. [3]

 Demineralized freeze dried bone allograft (DFDBA) consists primarily of collagen with some residual proteins; including an array of bone growth and differentiation factors like bone morphogenetic proteins (BMPs), which constitute osteoinductive components of bone. In addition to BMPs, other growth factors such as platelet-derived growth factor and transforming growth factor-β are also present. BMP has been shown to up regulate the expression of cbfa1 (core-binding factor subunit alpha-1)- the master switch that regulates osteoblast differentiation. BMP exerts its effects primarily through the SMAD (Suppressor of Mothers against Decapentaplegic) pathway although other mechanisms have been suggested. [4]

 Autogenous grafts, demineralized freeze-dried bone allografts(DFDBAs), biologic mediators alone or with DFDBAs, and bovine bone xenografts have demonstrated regenerative potential. DFDBAs have repeatedly demonstrated significant improvements in soft and hard clinical tissue parameters for the treatment of intraosseous periodontal defects. Substances present in the demineralized bone graft material, bone morphogenic proteins, stimulate local cell cycles to produce new bone. The freeze drying process destroys cells while maintaining cellular morphology and chemical integrity. These two factors, in conjunction with other materials, enhance periodontal regeneration and/or bone fill. [12]