The effect of age on the cellular immune response to dento‐gingival plaque extract

The Relationship between the cellular immune response to dento‐gingival plaque extract and age was exmined in 28 individuals (age range 21−47 for 27 subjects, one subject aged 64). There was a decrease, with age, in the response in a sub‐group of individuals with a severity of disease ranging from PI 4.1−7.3. There was also a correlation between the degree of disease (range PI 0.4−7.3) and the product of the numerical indicator of the response and the age of the 28 individuals studied. the significance of these findings in relation to the history of the disease is discussed.