inclusion criteria  Patients must be free from any systemic diseases according to criteria of Modified Cornell Medical Index. Males and females aged ≥18 years old. All subjects should be cooperative.  exclusion criteria  females, who were lactating or pregnant, will be excluded. smoker's or former smokers also will be excluded . any other periodontal diseases, except generalized grade c periodontitis or molar-incisor grade c periodontitis Patients received antibiotics or non- steroidal anti-inflammatory drugs 3 months or periodontal treatment 6 months' before the beginning of the study