[Radiation caries].

Abstract

Two mechanisms are discussed regarding etiology and pathogenesis: the direct mechanism by radioeffect on teeth, lying in irradiation field, and the indirect mechanism by alteration of the secretion from salivary glands (hypo- and dyssalivation, xerostomia), alteration of the physiological mouth-flora (dominance of Streptococcus mutans) and deficient mouth and tooth hygiene by the patients. Clinically four types of radiogenic tooth defects are discerned: the superficial carious destruction of the necks of the teeth, the change of the tooth-colour to brown-black, an early gradual fuse of the edges and occlusal plane of teeth and generalised superficial defects. With the tumor diagnosis and before the beginning of radiotherapy a total dental examination of the whole mouth-cavity is to do. The therapeutic measures conform to the dimension of dental caries and the bone reduction in consequence of parodontopathies. On principle as many teeth as possible are restored and preserved, only all teeth, that can not be restored in fact and have an uncertain prognosis, are extracted selectively considering a most careful atraumatic surgical technique. The programme for mouth hygienics and tooth prophylaxis carrying out during and for many years after radiotherapy includes a careful and routine cleaning of teeth of films and tartar, frequent rinsing of the mouth with Bepanthene-, Subcutin- or sodium chloride-sodium bicarbonate solution, daily fluoride-dose by mean of fluorine gel or gel carrier, a thorough instruction and motivation of the patients and an after-care in short intervals, to recognize a reduction of cooperation, to diagnose complications as soon as possible and to begin a suitable therapy. Extraction of teeth after radiotherapy was contraindicated absolutely in the past because of the risk of following osteoradionecroses. Recent reports however show, that the risk of a postradiotherapeutic tooth extraction is not so high as suspected primarily, if the indication is paid attention to and the extraction is done according respected technical regulations. Special care has to be given to manufacture and fitting in artificial teeth. It has not to be done until all essential therapeutic effects are eased off, that usually occurs 1 to 1 1/2 years after the end of therapy.