The most common acute oral problems occurring after chemotherapy are mucositis , infection, pain, and bleeding.It is thought that chemotherapy worsens perodontal disease and increases the incidence of caries but this ahs not been concusively proven. In study of 299,records of old, 313,461 12-year-old, and 301,930 15-year-old children born between 1984 and 1988 in a nationwide population-based study linking records from Danish Cancer Registry , children whose dental examinations had been preceded by a cancer diagnosis (288 7-year-old, 459 12-year-old, and 526 15-year-old) were compared with children without cancer according to presence of caries: caries-free children; children with any caries experience; and children with severe caries experience (i.e., caries in one or more smooth tooth surface). Children diagnosed with cancer before the age of 5 years did not have increased caries prevalence in permanent teeth at ages 12; and 15. Children diagnosed with cancer between 5 and 6 years of age had an increased prevalence of severe caries at age 12 years (prevalence ratio (PR) = 1.59 (95% CI: 1.09-2.31; P = 0.02)), but this difference disappeared by age 15. For children diagnosed with cancer at 5 or 6 years of age and who received radiation therapy the PR of severe caries was 1.52 (95% CI: 0.97-2.37; P = 0.07), 2.13 (95% CI: 0.89-5.10; P = 0.09), and 0.31 (95% CI: 0.07-1.45; P = 0.13) at ages seven, 12 and 15 years respectively. Similar findings were shown by other pediatric studies. In adults, there is more perodontal disease but less carries, since pulp cell turnover is less.
In summary, the evidence is sufficient to recomend close dental followup and preventive care during chemotherapy but insufficient to be able to definitively ascribe past dental decay of chemotherapy alone.