Periodontitis is a chronic inflammatory disease that affects the supporting structures of teeth, resulting in tooth loss. Halitosis (fetor oris) is a general term used to describe an unpleasant or offensive odour emanating from the oral cavity. Periodontal disease results in an unpleasant odour

           Probiotics are “live microorganisms which when administered in adequate amounts confer a health benefit on the host” (WHO 2002). In oral cavity, probiotics can create a biofilm, acting as a protective lining for oral tissues against oral diseases.

This study evaluates the efficiency of probiotics in preventing halitosis in chronic periodontitis patients.

          A total number of 26 cases of chronic periodontitis with halitosis will be selected randomly by self-evaluation (problematic, very strong, strong, moderate, light) and  organoleptic method (0-5point score) and will be divided in to test group A(SRP+ Probiotics) and control group B (SRP+ Placebo) including both males and females in the age group of 20-70 years. The study will be explained to each of the patients selected randomly and his/her written consent will be obtained prior to the commencement of the study. After qualifying for the study, 5 clinical variables will be evaluated at the baseline by the examiner who will be recording all measurements in a single blind design including probing pocket depth (PPD), clinical attachment level (CAL), sulcus bleeding index (SBI), Periodontal index (PI), wrinkel tongue coating index (WTCI) .After the initial clinical evaluation subgingival samples will be collected by inserting two consecutive paper points in to gingival crevices for 10 seconds. Then the samples will be given for the analysis of microbiological data, colony forming unit (CFU) per ml for total anaerobic flora .After the sample collection scaling and root planing will be done on both groups. The patients in group A will be advised to use probiotic tablets and group B will be given placebo. Patient will be recalled 4weeks and 8weeks after initial scaling and root planning and the above measurements will be repeated and samples are collected at 1^st and 3^rd months and given for microbiological investigation.