Author: Alan B. Sheiner DDS
Common side effects from radiation therapy are not stressed enough in dental schools, but they can be managed and even prevented.
A few weeks ago, I was contacted by a retired physician with whom I had not spoken for a number of years since he retired from practice to become a “gentleman farmer” in the country. While I was happy to hear from him, his news was not so good. He was calling because he had been treated for base of tongue cancer and his teeth were “coming apart”. His cancer treatment consisted of chemotherapy and radiation therapy. Unfortunately, he somehow “slipped through the cracks” and his oral cavity was now suffering from some of the side effects of the cancer therapy – fortunately he is currently cancer free.
The oral cavity, one of the most complex and visible organ systems in the body, is invariably compromised as a result of treatment for head and neck cancer. Whether the malignancy is to be treated by surgery, radiation therapy, chemotherapy or a combination of these modalities, the function, if not also the form, of the oral cavity will be impacted. Aside from the obvious physical changes after cancer surgery to the head and neck region, there are issues which usually accompany radiation therapy to the head and neck region.
There may be side effects from cancer therapy, some of which can be devastating, but preventable or manageable with proper precautions and care. The most common side effects for head and neck cancer patients who undergo radiation therapy are:
Dry Mouth (xerostomia)
Post Radiation Tooth Decay
Inability to open the mouth wide (Trismus)
Necrosis of soft tissue and bone (osteoradionecrosis)
Impaired ability to heal from wounds in the oral cavity
Prior to commencement of active treatment, each patient should be thoroughly evaluated by a dentist well versed in the management and care of the irradiated head and neck cancer patient. Unfortunately, this subject has not been stressed in dental school. Even if a dentist has had some instruction, his or her clinical experience might be quite limited. A real life example of this is a lady irradiated for a parotid gland tumor. The parotid gland (we have two) is a major salivary gland. Her general dentist provided her with fluoride applicators, but unfortunately this practitioner did not appreciate the importance of using a neutral pH fluoride gel. The acidulated fluoride gel, normally used when a dentist or hygienist gives a fluoride treatment, literally ate into the surfaces of this woman’s porcelain crowns. Now, in addition to having a dry mouth from radiation, she also has multiple crowns with surfaces like sandpaper. These expensive restorations could not be salvaged and required replacement. In short, the dentist remembered that radiated patients should have daily fluoride treatment. He just did not have a genuine understanding of how to accomplish the task properly.
The most common and profound side effects of irradiation to the head and neck region are: dry mouth (since the major salivary glands are almost always damaged by the therapy), post-irradiation dental caries (a preventable situation), the risk of osteoradionecrosis (non-healing chronic bone death in irradiated bone which has a compromised blood supply) and trismus (an inability to open the mouth fully).
As always, your dentist is the best resource and first person you should see for consultation.