The connection between obesity and gum disease isn't as simple as cause-and-effect, said Andres Pinto, professor of oral and maxillofacial medicine and diagnostic sciences at the Case Western Reserve University School of Dental Medicine and co-author of the study published in the British Dental Journal.

Instead, the relationship centers on what both diseases have in common: inflammation.

Examining a plethora of existing studies, researchers found that data showing increased body mass index, waist circumference and percentage of body fat to be associated with an increased risk to develop gum disease, also known as periodontitis. Most studies analyzed data from population subsets at one point in time, as opposed to studying the same population over a longer period.

They concluded that changes in body chemistry affect metabolism, which, in turn causes inflammation -- something present in both maladies.

"Periodontal disease occurs in patients more susceptible to inflammation -- who are also more susceptible to obesity," Pinto said.

This information can inform how health-care professionals plan treatments for patients suffering from obesity and/or gum disease, Pinto said.

"Oral health-care professionals need to be aware of the complexity of obesity to counsel their patients about the importance of an appropriate body weight and maintaining good oral hygiene," he said.

Pinto said further research on the relationship between gum disease and obesity is needed, noting there is, at this point, limited evidence to recommend changes in treatment planning.

"There is a thought, from the clinical perspective, that if you treat one of the issues, it may impact the other," he said. "This is the big question. For example, if we treat obesity successfully, will this impact periodontal disease to the point of being of clinical relevance compared to control population. The jury is still out given the paucity of controlled, well designed, clinical trials on this issue."