Dental caries is the among the commonest and highly prevalent diseases worlwide affecting 486million children with primary teeth and 2.4billion adults with permanent teeth globally.According to WHO, dental caries affects 60–90 % of schoolchildren globally, mainly in developing countries resulting in pain,infections,undernutrition thereby affecting growth and development and decrease in overall quality of life.Therefore it is of utmost importance to treat effectively and prevent dental caries from progressing, at an earlier stage, to avoid all the complications.The ideal way of treating moderately affected carious tooth is by removing the bacteria by cavity preparation followed by a cement or resin-based dental restoration.

However,the complete eradication of bacteria prior to insertion of restoration plays an important role in determining the longevity of the restoration and correspondingly the success of the treatment. Bacteria can remain viable on the dentinal surface even after cavity preparation. They may survive and multiply in the presence of microleakage, which may lead to pulpal irritation, risk of recurrent caries and/or postoperative sensitivity and ultimately failure of the restoration. Attempts at the complete removal of deep carious dentin, by solely mechanical means, may result in pulp exposure and gross destruction of the tooth structure.

To cope up with the above drawbacks, the concept of cavity disinfection has been introduced by some authors, which involves cleansing of the cavity with antimicrobial agents prior to placement of restoration. Multiple disinfectants(CHX,NaOCl,Laser,Ozone,Propolis etc.) have been used in clinical dentistry, to reduce or eliminate bacterial load and sterilize dentin during cavity preparation.

Chlorhexidine digluconate in the form of 2% aqueous solution has been  widely considered as a  biocompatible,effective and toxicologically safe disinfectant.

Chitosan, derived from the deacetylation of chitin, obtained from the shells of marine crustaceans is a natural nontoxic, biocompatible, biodegradable polysaccharide with tested antibacterial properties. Prior studies have described the antimicrobial potential of chitin, chitosan, and their derivatives against Streptococcus mutans and other streptococci bacteria. Among these derivatives, phosphorylated chitosan(p-chitosan) exhibits bactericidal, bioabsorbable, osteoinductive, and metal chelating properties. Since phosphate groups of p-chitosan can bind calcium ions to form nucleating sites, p-chitosan would induce the formation of a calcium phosphate layer favouring remineralization of the carious lesion.