The oral cavity is a complex microenvironment consisting of multiple bacterial and fungal species, their associated biofilms, and a cytokine milieu influenced by constant inflammatory stimulation. Multiple infectious consequences of poor oral health have been extensively described and primarily affect older adults. Probably the most common sequelae of poor oral health in aged persons is a risk of aspiration pneumonia. The risk of aspiration pneumonia is greatest when periodontal disease, dental caries, and poor oral hygiene are compounded by swallowing disease, feeding problems, and poor functional status. The effectiveness of oral hygiene interventions for preventing aspiration pneumonia and barriers to oral care of nursing home patients require additional study, but the current state of research in these areas is reviewed in this manuscript. The expense of aspiration pneumonia as a nursing home complication makes dental hygiene a potentially cost-saving intervention.