The aim of this trial is to compare the effect of autogenous demineralized dentin graft combined with injectable PRF loaded with metronidazole (sticky demineralized tooth releasing metronidazole) versus autogenous demineralized dentin graft (ADDG) alone on alveolar ridge preservation after extraction of non restorable, infected single-rooted teeth

Many studies have reported an approximately 50% reduction in alveolar bone both the horizontal and vertical directions over 12 months with more than two-thirds of the reduction occurring in the first three months after extraction. Alveolar ridge preservation is a procedure that attempts to reduce bone dimensional changes that naturally take place following tooth extraction. During the last decade, efforts have been made to confirm procedures that can prevent bone resorption after extraction. The use of bone grafts aim to promote bone healing and assist bone regeneration. Various types of materials are used for socket preservation, such as autogenous bone, allograft bone, xenograft materials, and alloplast materials.

Dentin contains several growth factors, including transforming growth factor beta (TGF-β), insulin-like growth factor-II (IGF-II) and bone morphogenetic protein-2 (BMP-2), which could be of pivotal importance during any healing event. Demineralization of dentin has been further proposed to expose its collagen matrix, liberate 'fossilized' growth factors and thereby enhance its regenerative capacity.

It has been proven that autogenous demineralized dentin graft is effective at reducing dimensional losses of alveolar sockets after 6 months, with no adverse effects.

The efficacy of platelet rich fibrin (PRF) in promoting wound healing and tissue regeneration is at the center of a recent academic debate. The liquid fibrinogen has been shown to bind particulate bone grafts, which are then called "sticky bone". This binding improves the stabilization of the particles in the defect. It adds a potential biological effect, which could accelerate the soft tissue healing process and optimize the handling properties of the granules.

The purpose of this clinical trial is to assess the capacity and the clinical feasibility of the dentin graft processed with injectable platelet rich fibrin (I-PRF) to an adherent, tooth-derived conglomerate for socket preservation. Moreover, Platelet-rich fibrin incorporated with antibiotics showed long-term anti-bacterial effect against F. nucleatum and S. aureus.

Both autogenous demineralized dentin graft combined with injectable PRF (sticky demineralized tooth) and autogenous demineralized dentin graft (ADDG) alone, with or without collagen membrane, have been utilized for alveolar ridge preservation or augmentation but the superiority of one form over the other is not yet clear.

Inclusion Criteria:

• Non-restorable tooth indicated for extraction
• Single-rooted teeth
• Inactive infection related to the tooth
• Motivated patients, agree to sign informed consent and complete the follow-up period

Exclusion Criteria:

• Pregnant females
• Active infection at extraction site
• Smokers
• Systemic conditions affecting healing (e.g. diabetes, medications as bisphosphonates...)