Oxidative stress lays at the heart of periodontal tissue damage, resulting from host-microbial interactions either as a direct result of excess reactive oxygen species (ROS) activity or indirectly as a result of activation of redox-sensitive transcription factors and creation of pro-inflammatory state.

Free radicals and ROS are essential to many biologic processes. At low concentrations, these free radicals stimulate the growth of fibroblasts and epithelial cells in culture, but at higher concentrations it may result in tissue injury. The antioxidant system developed by human body functions to detoxify ROS and modify them to form less reactive species. ROS includes hydrogen peroxide, hypochlorous acid, singlet oxygen and ozone.

In general, treatment of periodontitis is multifaceted and vigorous, including mechanical, antibiotic and antiseptic therapy, and the various treatment approaches should be employed within a short time period. Now a day various novel therapeutic approaches are tried as an alternative to conventional therapy or in combination with conventional therapy to reduce load periodontopathic pathogens. The ultimate goal of periodontal therapy is to regenerate the lost periodontal tissue. One of the effective therapeutic measures can be topical oral oxygen therapy (TOOTh).It is a low pressure oxygen therapy which applies oxygen directly to the wound site.

Wound healing requires a variety of cells to increase their metabolic activity, resulting in a high oxygen demand. Oxygen at the wound site has been shown to promote  wound healing by stimulating several processes, including neovascularization, collagen production. Collagen forms the structural network of the connective tissue component of oral mucosa and is present in fibrillar form.It strengthens the blood vessels and play a role  in tissue development. It also plays a key role in regulating periodontal tissues during the development and regeneration. Collagen can be viewed by staining the tissue with the special stain known as masson trichrome stain which is tricoloured stain and stains collagen in blue colour. One of the example of TOOTh is the application of blue^® m gel which uses a mechanism of delivering oxygen in controlled manner directly to trauma site and is safe,effective and non-invasive therapy.

The application of this gel releases oxygen molecules that can penetrate much deeper into the biofilm to kill the anaerobic bacteria even in the perimucosal seal around the implant.It even acts as a bone growth accelerator by the presence of lactoferrin which potentially stimulates the proliferation and differentiation of primary osteoblasts.The application of the gel is very simple as it is placed directly deep into the pocket with a disposable syringe. It has wide variety of uses in gingivitis, periodontitis, peri implantitis, acute wound healing after tooth extraction etc.