Research published by the University of Helsinki, Finland, indicates that cytostatic and radiation therapies administered before stem cell transplantation often damage children's permanent teeth.
Detrimental effects of cytostatic and radiation therapies on dental development have been known for a long time, but knowledge about the dental consequences of high-dose anticancer therapy preceding stem cell transplantation has so far been scarce. Paivi Holtta, Licentiate in Dentistry, from the Institute of Dentistry, University of Helsinki, has studied the effects of high-dose anticancer chemotherapy and total body irradiation on the development of permanent teeth.
Tooth development is a genetically controlled chain of events that can be disturbed by various environmental factors. The development of permanent teeth begins as early as the 20th week of gestation and continues until the age of 14 to 15 years with the exception of wisdom teeth, which still continue their development for several years. All this time teeth are vulnerable to developmental aberrations.
The children examined in the current study, treated for cancer or aplastic anemia, had received stem cell transplantation at the age from 1 to 9.4 years, preceded with a high-dose anticancer chemotherapy and, in most cases, with total body irradiation. In her research, Hölttä studied how many of the treated children lacked permanent teeth or had unusually small teeth, and how often dental roots were poorly developed.
The results indicated that 31% of the treated children lacked permanent teeth (as opposed to 8% of the Finnish population), when wisdom teeth were excluded. Lack of permanent teeth was most frequent (77%) among children who had been less than three years old at stem cell transplantation. The highest number of missing teeth was 12. Those who had been over five years of age at stem cell transplantation lacked only wisdom teeth. A significant finding was that a high-dose anticancer chemotherapy alone caused a lack of permanent teeth nearly as often as when combined with total body irradiation, which, however, slightly increased the number of missing teeth.