Root conditioning و عوامل موثر در آن جهت رژنراسیون بافت های پریودنتال

Periodontitis affected root surfaces are hypermineralized and contaminated with cytotoxic and other biologically active substances.The instrumented surface will inervitably be coverd by a smear layer following root planing with or without flap.Smear layer is resistant to saline rinsing, but may be removed with agents such as acids (e.g.citric acid), tetracyclines, EDTA, and laser.Low pH aqueous solutions such as citric acid have been used in surgical periodontal therapy mainly for two reasons, It dissolves smear layer after a relatively short exposure time and it has been claimed to selectively remove root surface associated mineral exposing collagen to varying degrees. A root surface coated with collagen appears to be a preferred surface for fibroblast attachment, a cellular event fundamental to successful periodontal wound healing.Several studies indicate the potential of tetracycline (TTE-HCL) in periodontal regeneration. Its acidic pH suggest that it can be used as a demineralization agent and removing the smear layer and exposing collagen matrix of the dentin.Chalating agent (EDTA) working at neutral pH appears preferable with respect to preserving the integrity of exposed collagen fibers, early colonization, and wound healing. In addition, etching at neutral pH has been reported preserve adjacent tissue- vitality, while etching at low pH necrotizes the fiap and adjacent periodontium.Clinical and subclinical studies have demonstrated laser waves can remove calculus and bacterial plaque and pocket epithelium and strile the root surface and can expose the dentin collagen and dentinal tublules, and leads to pronounce reducing of probing depth around teeth diseased with periodontitis.