Role of interleukin gene polymorphism in patients with chronic and aggressive periodontitis: A narrative review

Periodontitis is a microbial disease of tooth-supporting tissues that results in progressive destruction of surrounding soft and hard tissues with eventual loss of tooth or tooth mobility. A comprehensive literature search was performed by using the keywords: periodontitis, periodontal disease, combined with the word genes, mutation, or polymorphism. Gene polymorphism studies with a reported genotype frequency in chronic periodontitis (CP) and aggressive periodontitis (AgP) patients were searched and reviewed. There has been a growing evidence of polymorphisms in the interleukin (IL)-1, IL-4, IL-6, IL-10, IL-12, and tumor necrosis factor-alpha with CP and AgP in certain populations. However, carriage rates of the rare (R) allele of any polymorphism varied considerably among studies, and most of the studies appeared underpowered and did not correlate for other risk factors, hence furthermore researches are required including large sample size, different races, genotypes, and other risk factors which were found to be influential in expression and severity of CP and AgP to get a more comprehensive insight into the contribution of IL gene polymorphisms in CP and AgP.