A prospective observational case–control study involving 150 participants divided into three groups on the basis of the basic periodontal examination index: healthy ( n  = 21), gingivitis ( n  = 52) and periodontitis ( n  = 77). Salivary occult blood tests were conducted using the Onsite FOB‐Hi Rapid Test. Descriptive and analytical statistical analyses were performed using Fisher's exact test and chi‐square tests.

The FOBT kit demonstrated a sensitivity of 91% and a specificity of 100%. The number of teeth significantly influenced test results ( p value = 0.021, chi‐square). Age ( p value = 0.09, chi‐square) and sex ( p value = 0.213, chi‐square) did not significantly impact the test's performance.

The FOBT kit demonstrates high sensitivity (91.3%) and specificity (100%) as a screening tool for periodontal disease. Its affordability and global availability make it suitable for detecting periodontal disease across different age groups, sexes and numbers of teeth.