Periodontal Disease, Tooth Loss, and Cancer Risk

Abstract

Periodontal disease, which includes gingivitis and periodontitis, is highly prevalent in adults and disease severity increases with age. The relationship between periodontal disease and oral cancer has been examined for several decades, but there is increasing interest in the link between periodontal disease and overall cancer risk, with systemic inflammation serving as the main focus for biological plausibility. Numerous case-control studies have addressed the role of oral health in head and neck cancer, and several cohort studies have examined associations with other types of cancers over the past decade. For this review, we included studies that were identified from either 11 published reviews on this topic or an updated literature search on PubMed (between 2011 and July 2016). A total of 50 studies from 46 publications were included in this review. Meta-analyses were conducted on cohort and case-control studies separately when at least 4 studies could be included to determine summary estimates of the risk of cancer in relation to 1) periodontal disease or 2) tooth number (a surrogate marker of periodontal disease) with adjustment for smoking. Existing data provide support for a positive association between periodontal disease and risk of oral, lung, and pancreatic cancers; however, additional prospective studies are needed to better inform on the strength of these associations and to determine whether other cancers are associated with periodontal disease. Future studies should include sufficiently large sample sizes, improved measurements for periodontal disease, and thorough adjustment for smoking and other risk factors.

Keywords: cancer; meta-analysis; periodontal disease; periodontitis; review.

Figure 1.

Literature search and selection flow chart. Systematic reviews were used to find relevant articles (–24). Hujoel et al. (32), Tezal et al. (37), Moergel et al. (38), and Michaud et al. (11, 70) described both periodontal disease and tooth loss exposure; Ren et al. (16) and Guha et al. (43) have 2 studies in each publication.

Figure 2.

Random-effects meta-analysis of 5 cohort studies assessing the associations between periodontal disease and lung cancer risk. CI, confidence interval.

Figure 3.

Predicted linear dose-response relationship between number of missing teeth and oral cancer risk using data from 7 case-control studies. The solid black line is the predicted linear trend, and the gray area is the 95% confidence interval of the predicted linear trend. The 7 case-control studies included in the analysis are described by Kabat et al. (71) (female), Zheng et al. (72) (male and female separately), Bundgaard et al. (73) (both sexes), Rosenquist et al. (74) (both sexes), Guha et al. (43) (Central Europe, both sexes), Guha et al. (43) (Latin America, both sexes), and Chang et al. (44) (both sexes).

Figure 4.

Random-effects meta-analysis of 4 cohort studies assessing the associations between periodontal disease and colorectal cancer risk. CI, confidence interval.