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A 41-year-old man experiencing homelessness presents to a clinic on "skid row" with a toothache (Figure 47-1). He has a history of alcoholism and smoking. Many of his teeth are loose and a number of his teeth have fallen out in the past year. He acknowledges that he does not floss or brush his teeth regularly. He has been sober for 60 days now and wants help to get his teeth fixed. He states that no one will hire him with his teeth as they are. He also has pain in a molar and wants something for the pain until he can see a dentist. On oral examination, you see missing teeth, generalized plaque, and teeth with multiple brown caries.


Severe caries in a man experiencing homelessness. (Reproduced with permission from Richard P. Usatine, MD.)


Dental caries is a multifactorial disease that is primarily caused by an interaction between bacteria and fermentable carbohydrates producing acid that has potential to demineralize the tooth surface over time. Host factors, such as the plaque (biofilm) adherence, quality and quantity of saliva, immune system response, use of fluoride, and a diet that is caries-promoting, play a role in the formation of incipient demineralized lesions that progress to dental caries. Caries risk is impacted by factors that may be behavioral, biologic, environmental, lifestyle-related, and physical. Age, diabetes, ethnic origin, gingival recession, smoking, and socioeconomic status are frequently associated with high caries prevalence.1


Dental decay, dental cavities, cavitated lesions.


  • Many adults (e.g., 27.3% of those 20 to 34 years of age, 27% of those 35 to 49 years of age, and 25.5% of those 50 to 64 years of age) have untreated dental caries (Figure 47-2).2

  • Approximately one in five of the older adults in the United States (e.g., 18.5% of those 65 to 74 years of age, and 19.4% of those 75 years of age and over) continue to have untreated dental caries.2

  • Black and Hispanic adults, younger adults, and those with lower incomes and less education have more untreated decay.3

  • Adults over 65 are predisposed to a higher prevalence of root caries than younger populations due to an increase in exposed root surfaces from gingival recession (Figure 47-3). This prevalence is difficult to estimate due to existing tooth loss that confounds the data.4

  • An association between tobacco use and caries among adults is not conclusive; however, tobacco use is associated with increased caries development during adolescence.5


Dental caries in the United States. (Data from CDC/NCHS, National Health and Nutrition Examination Survey, 2011–2012.

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