10 Pretreatment Dental Evaluation
A multidisciplinary approach to care is recommended for head and neck cancer patients in order to improve overall treatment outcomes. Dental providers should be included in this team and a complete oral/dental examination and any necessary dental treatment, such as extractions and restoration of restorable teeth, should be performed prior to radiation or chemotherapy. This process is critical in order to prevent serious oral problems that could result in delays or cessation of cancer treatments. Providers should educate patients on common oral side effects including mucositis, infections, xerostomia, taste changes, soft-tissue and/or bone necrosis, and exacerbation of dental and periodontal diseases. In addition, thorough home care instructions and fluoride supplementation should be incorporated into management due to increased caries risk and lifelong risk of osteoradionecrosis associated with radiation therapy to the head and neck region.
The most common modalities used to treat head and neck cancer are comprised of surgery, radiation therapy, and chemotherapy. These aggressive cancer treatments not only act upon tumor cells, but also produce noxious effects to normal cells, including the oral mucosa and salivary glands. The short- and long-term effects of this toxicity on the oral cavity and dentition have been well documented. 1 , 2 Early evaluation and treatment by a trained dental team can diminish or prevent some of these oral complications, such as mucositis, oral infection, and osteoradionecrosis (ORN). It is therefore important that patients undergo a thorough dental evaluation prior to the initiation of head and neck cancer treatment.
10.2 Nonodontogenic Considerations
As the treatment of the cancer patient is multifaceted, communication between different providers to organize and coordinate care is critical in order to improve outcomes. A focus on the concept of a multidisciplinary team has therefore become increasingly prominent over the years. For head and neck cancer patients, this team often consists of head and neck cancer surgeons, reconstructive/plastic surgeons, radiation oncologists, medical oncologists, pathologists, speech and language therapists, dietitians, social workers, and dentists. Accordingly, it is important for the dental professional to take a multidisciplinary approach and communicate with other providers as there are numerous nonodontogenic factors to consider when constructing an initial dental treatment plan for head and neck cancer patients.
10.3 Diagnosis/Patient Prognosis
The patient’s medical history, diagnosis, prognosis, and treatment plan should be obtained from the multidisciplinary team. If the patient prognosis is extremely poor or medical status extremely compromised, dental treatment may sometimes be deferred and the team may opt to address future dental sequelae as they arise.
10.4 Radiation Therapy Factors
A significant challenge to the dentist is the determination of what preexisting oral conditions or teeth require treatment in order to limit the risk of ORN following radiation therapy. ORN of the jaw is one of the most severe chronic side effects of radiation treatment to the head and neck region. First described by Regaud in Paris in 1922, ORN is defined as nonhealing exposed bone in a previously irradiated area present for over 3 months. 3 Other features include pain, halitosis, dysgeusia, food impaction in the area of exposed sequestra, pain, fractures, and fistulas. 4 It can occur in both dentate and edentulous patients, either spontaneously or following trauma, with most cases of ORN occurring after tooth extractions. 5
As proper dental management is of utmost importance for the prevention of ORN, the dentist should receive from the radiation oncologist the general radiation plan prior to the initiation of treatment. Type of radiation, total cumulative dose, and intended field of direct radiotherapy should be considered when determining a dental treatment plan. All parts of the jaws are not necessarily included in the field of radiation and if the radiation dose to the area of the mandible or maxilla is less than 50 to 60 Gy, the risk of osteonecrosis has usually been considered lower (see Chapter 41 Radiotherapy Related Side Effects in the Treatment of Oral Cavity Malignancies). 6
Conventional (two- and three-dimensional conformal radiotherapy) techniques can result in significant side effects and decreased quality of life. Over the last few decades, improvements have been made in radiotherapy for the treatment of cancer including intensity-modulated radiotherapy (IMRT), which manipulates photon and proton beams of radiation to conform to the shape of a tumor and reduce doses to normal tissues. Other advancements like volumetric intensity-modulated?arc therapy and image-guided radiotherapy have also helped improve IMRT further. 7 There has been a reduction in the rates of ORN with these newer advances, which may be attributed to more conformal dose distributions that spare parts of the mandible that would have received a high dose with more conventional techniques. Salivary gland sparing with these advancements may also decrease the risk for development of dental caries. 8
Finally, the scheduled time of commencement of radiotherapy and amount of time available for the dental assessment are important to take into consideration as this may influence prioritizing certain treatments if there are time constraints. In some cases, due to severity of the tumor and disease, dental treatment may be deferred so that radiation can proceed without delay. In such cases, the initial dental evaluation should be scheduled soon after cancer diagnosis in order to allow for sufficient time to complete any necessary dental treatment.
10.5 Patient-Related Factors
10.5.1 Patient Demographics
Certain demographic factors should be considered as they can influence health care outcomes. The socioeconomic status/finances of a patient should be considered as this may lead to difficulties with health care access. Of note, head and neck cancer patients to receive high doses of irradiation will have a lifelong risk of ORN should they require dental extractions in the future. If the patient lacks dental insurance or cannot afford regular and preventative dental care that is required, consideration may need to be given as to whether any teeth should remain in the proposed high-dose field of radiation. The age of a patient should also be considered, as younger patients must maintain disease-free dentition longer in order to avoid future complications.
10.5.2 Patient Compliance and Dexterity
Patients with a dental phobia, compromised manual dexterity, or a demonstrated lack of motivation to perform oral hygiene measures may require a more aggressive preradiation dental treatment plan. The provider may lean toward extracting all teeth in areas to receive high doses of radiation in these instances.
10.5.3 Patient Wishes for Dental Extraction
All clinicians should view the treatment planning process as a shared process and an educational experience for the patient. Treatment advantages, disadvantages, risks, and alternatives should all be reviewed. Alongside the actual indication and diagnosis of the teeth, the relevant wishes of the patient regarding tooth extraction should be considered when fabricating a treatment plan.
10.6 Oral Assessment before Treatment
Following a standard history, including medical diagnoses, a social and dental history, and current and recent complaints, a thorough oral and dental examination should be conducted. The purpose of the dental examination is to determine definitive diagnoses and prognoses for individual teeth in order to identify those that require aggressive or invasive dental treatment prior to chemotherapy and/or radiation treatment. Infection control should be instituted prior to cancer treatment in order to improve patient outcomes, as a healthy oral cavity has been shown to improve general comfort and result in fewer interruptions during treatment. 2
In addition to a clinical examination, a through dental evaluation should incorporate radiographic images. Select dental radiographs are a valuable diagnostic tool to aid in the assessment of areas for potential infection that may not be visually obvious. A panoramic radiograph and/or a full series of dental radiographs should be taken for dentate patients to assess for any bony pathology, screen for caries (tooth decay), and aid in the detection of periodontal disease (▶ Fig. 10.1). A panoramic radiograph should also be taken for edentulous patients in order to screen for any bony pathology, submucosal or intrabony root fragments, and impacted teeth.