Published: May 2003
Pre-radiation therapy dental appointments should establish a dentition that the patient will be able to
maintain for the rest of his or her life. The evaluation should consider the patient's previous interest in oral health, as well as current motivation to comply with a rigorous and lifelong preventive oral health program. The financial commitment of the preventive measures and the costly reality and complications of non-compliance should be strongly emphasized.
All hopeless and questionable teeth (i.e. teeth with furcation involvement or advanced periodontitis, or teeth that are impacted, nonessential or nonrestorable), implants with questionable prognosis, root fragments and other bone pathology within the field of radiation should be removed prior to radiation. Since osteoradionecrosis has been reported to develop in irradiated jaws as late as 25 years following radiation therapy, serious consideration must be given
to the extraction of any teeth that may be a problem in the future. Total odontectomy, followed by alveoloplasty or alveolectomy should be performed on patients with minimal potential for maintaining adequate oral hygiene, a significant percentage of non-restorable teeth and/or severe periodontitis.
Extractions and surgery, with tension-free primary tissue closure and antibiotic coverage, should be performed to allow at least 14 days of healing prior to initiation of radiation therapy. The precise time interval depends upon the extent of surgical insult and the philosophy of the treatment center.
Pre-prosthetic surgery, including removal of interfering tori and exostoses, should be performed at this time since additional surgical procedures are contraindicated on irradiated bone.
Proper evaluation of existing removable prostheses is essential. The patient should leave appliances out of the mouth as much as possible during the period of therapy, especially if mucositis develops. New prostheses should not be constructed for at least 3-6 months following radiation, depending upon the integrity of the mucosa, severity of xerostomia and surgical scarring.
Patients with temporomandibular disorders can experience increased complications during and after radiation therapy to the head and neck. Conservative management should be planned at the time of the pretherapy evaluation.
Additional Needs of Children
Evaluate the dentition and estimate the exfoliation of primary teeth. Remove mobile teeth. Remove gingival operculum if there is a risk for entrapment of food debris or infection.
Patients who use tobacco should be advised to quit. Response to radiation therapy is improved in individuals that do not smoke. Facilitation in the quitting process may involve referral for cessation counseling or to a support group and, when appropriate, nicotine replacement therapy.
Analyze and modify the patient's daily dietary habits to eliminate highly cariogenic foods and drinks without compromising adequate caloric intake. Aggressive use of over-the-counter medications high in sugar content should be discouraged.
Treatment and Maintenance of the Teeth
Provide periodontal care, including prophylaxis and home care instruction.
Perform high priority restorations and eliminate sites of irritation.
Remove orthodontic bands if they are within the field of radiation.
To prevent demineralization of tooth structure, "radiation caries," the minerals normally provided by saliva must be replaced on a daily basis for the rest of the patient's life. The presence of fluoride ions enhances the teeth's ability to uptake calcium and phosphate ions; therefore, fluoride gel, and on occasion a calcium phosphate remineralizing gel, should be applied to the teeth in custom gel-applicator trays.
Several days before the initiation of radiation therapy, patients should begin their daily five-minute application of a fluoride gel. Acceptable fluoride gels include a 1.1% neutral pH sodium fluoride or a 0.4% stannous fluoride (unflavored). A neutral pH fluoride should be used by patients with porcelain crowns.
do not provide adequate fluoride coverage of teeth to prevent demineralization.
Custom Gel-Applicator Trays
Custom gel-applicator trays are fabricated on a vacu-form machine using a flexible vinyl mouthguard material. The trays should
completely cover all tooth structure. The edges should be tapered to reduce bulkiness and should be smoothed with either a rag wheel or felt cone or it can be flamed. To prevent the risk of soft and/or hard tissue necrosis,
the trays must not irritate the gingival or mucosal tissues.
The adaptation of the trays to cervical margins of the teeth should be checked and modified from time to time, as this thermoplastic material will gradually lose intimacy of fit.
Patient Instruction for Gel Application
The patient should be instructed to perform the following:
- Brush and floss teeth thoroughly.
- Place a thin ribbon of fluoride gel (or calcium-phosphate remineralizing gel) in each gel tray.
- Place the gel trays on teeth and leave in place for approximately five minutes. If the gel oozes from the tray, too much gel has been used.
- Remove the trays from the mouth and expectorate excess gel. Do not rinse mouth. Rinse trays thoroughly with water.
- Do not eat or drink for 30 minutes following applications.
*Many people find it convenient to apply fluoride while showering or bathing.