Should oral foci of infection be removed before the onset of radiotherapy or chemotherapy?

Pretreatment dental screening aims to locate and eliminate oral foci of infection in order to eliminate local, loco‐regional, or systemic complications during and after oncologic treatment. An oral focus of infection is a pathologic process in the oral cavity that does not cause major infectious problems in healthy individuals, but may lead to severe local or systemic inflammation in patients subjected to oncologic treatment. As head and neck radiotherapy patients bear a lifelong risk on oral sequelae resulting from this therapy, the effects of chemotherapy on healthy oral tissues are essentially temporary and reversible. This has a large impact on what to consider as an oral focus of infection when patients are subjected to, for example, head and neck radiotherapy for cancer or intensive chemotherapy for hematological disorders. While in patients subjected to head and neck radiotherapy oral foci of infection have to be removed before therapy that may cause problems ultimately, in patients that will receive chemotherapy such, so‐called chronic, foci of infection are not in need of removal of teeth but can be treated during a remission phase. Acute foci of infection always have to be removed before or early after the onset of any oncologic treatment.