Gum disease is caused by the presence of a mixed species biofilms containing bacteria, viruses, and fungi. This complex micobiome contains more than 600 bacterial species and 100 fungal species. 

Candida is a fungus that is most often found in periodontal (gum) disease and may be a contributing factor to disease progression.  

Candidiasis is an infection caused by Candida albicans and is the most common infection in the human oral cavity.  The colonization and proliferation of Candida in the oral mucous and in gum disease pockets is enabled by specific disease causing factors that they possess. Candida can act directly to cause disease or in conjunction with other bacterial species, or it can act as a cofactor that accelerates dental bone loss by producing cytokines (cell messenger molecules) that increase oral inflammation. 

Unniachan et al conducted a systematic review of the association between Candida species and periodontal disease.  The findings of 23 studies were summarized as follows: 22 out of 23 studies found an increased number of Candida species in patients with chronic periodontitis (the most common form of gum disease). So there is a good likelihood that Candida plays a role in periodontal disease.

Candida is an opportunistic fungus and its hyphae (growth structures) have been shown in the connective tissues of periodontal patients in association with other invasive bacteria such as P. gingivalis, P. intermedia, and A. Actinomycetemcomitans. 

Candida has multiple disease causing properties like adhesion, invasion, and biofilm formation and the ability to cohabit with harmful bacterial species.  Diabetic patients seem have a higher prevalence of Candida in periodontal pockets. 

Based on the results of the studies that were reviewed, it can be concluded that there is a strong association between the presence of Candida and gum disease. Future studies should establish exactly what role oral Candida (fungus) is playing in the progression of periodontal disease and whether anti fungal agents could be useful.

For more info refer to Unniachan et al. Association between Candida species and periodontal disease: A systematic review.  Curr Med Mycol. 2020 Jun; 6(2): 63–68.