“…It is also associated with immunodepressive effects due to decreased production of salivary antibodies and impaired neutrophil functioning, and an impaired buffering effect of the saliva which increases susceptibility to tooth decay (Darby & Walsh, 2010, p. 306; Voelker, Simmer‐Beck, Cole, Keeven, & Tira, 2013). Clinical studies have shown a positive correlation between smoking and periodontal disease (Bergstrom, 2014; Borojevic, 2012; Smejkalova et al, 2012) and caries rates (Aguilar‐Zinser et al, 2007; Voelker et al, 2013), although these links are also considered to be inconclusive (U.S. Department of Health and Human Services, 2014). Additional lifestyle factors that are often socioeconomic in nature, including different eating habits and oral hygiene maintenance, have also been shown to differ substantially between smokers (including secondhand smoking) and nonsmokers (Benedetti, Campus, Strohmenger, & Lingström, 2013; Hanioka, Ojima, Tanaka, & Yamamoto, 2011; Smejkalova et al, 2012).…”