Bone marrow transplantation (BMT) has become an increasingly common treatment option for those patients who have a disease that affects the bone marrow (BM) directly or indirectly. Because of the level of immunosuppression achieved in BMT, any problems the pediatric patient presents in the oral cavity can become life-threatening and increase the length of hospital stay, the patient's discomfort, and the treatment costs. The oral cavity is a reservoir for microorganisms thus by reducing their number through optimal care, immunosuppressed patients may decrease their chance of a life-threatening systemic infection from an oral source. Many BMT teams believe that toothbrushing increases the risk of bacteremia and bleeding; however, problems are more likely to arise when patients are not compliant with good oral hygiene habits. It is vital to educate the caretaker and the child about the importance of oral care in order to minimize discomfort and maximize the chances for a successful transplant. This paper discusses the important and unique role that pediatric dentistry has in the multiprofessional BMT team to help bring about a successful outcome through the prevention and treatment of the acute oral complications often seen in these patients.