Dental management of the irradiated patient.

There is an increasing number of patients receiving radiation therapy for oral malignancies. In many malignant tumors, radiation is often the treatment of choice, while in others it may be used in conjunction with surgery or chemotherapy. There are inherent dental and oral problems associated with radiation therapy. It is the purpose of this paper to deal briefly with the physical principles and the biological basis of radiation therapy. In addition, the specific radiation effects on oral mucous membranes, taste buds, salivary glands, bone, the periodontium and teeth will be discussed. Radiation complications in edentulous patients, and in particular the problems of wearing dentures in such patients will be evaluated. An approach to the problem of dental extractions and other dental treatments in the pre- and post-irradiated patient is suggested.     

The management of periodontal disease in patients who have received radiation therapy for head and neck cancer

Osteoradionecrosis is a common, serious sequela of radiation therapy for oral cancer. Patients who are to receive radiation therapy should have preradiation dental evaluation and treatment, oral hygiene instruction, and close dental follow-up during and after radiation therapy. Teeth with significant periodontal disease should be extracted before radiotherapy. After radiation treatment, advancing periodontal disease can be initially managed with conservative treatment, scaling and root planing, tetracycline, and good oral hygiene. Periodontal disease is a possible source of infection and may therefore predispose a patient to osteo-radionecrosis.     

Managing complications of radiation therapy in head and neck cancer patients: Part II. Management of radiation-induced caries

Head and neck cancer is becoming a more recognizable pathology to the general population and dentists. The modes of treatment include surgery and/or radiation therapy. Where possible, pretreatment dental assessment shall be provided for these patients before they undergo radiation therapy. There are occasions, however, whereby head and neck cancer patients are not prepared optimally for radiation therapy. Because of this, they succumb to complicated oral complications after radiation therapy. The management of xerostomia has been reviewed in Part I of this series. In this article, the management of dental caries, a sequalae of xerostomia following radiation therapy is reviewed.     

Managing complications of radiation therapy in head and neck cancer patients: Part V. Management of mucositis

Head and neck cancer is becoming a more recognizable pathology to the general population and dentists. The modes of treatment include surgery and/or radiation therapy. Where possible, pretreatment dental assessment shall be provided for these patients before they undergo radiation therapy. There are occasions, however, whereby head and neck cancer patients are not prepared optimally for radiation therapy. Because of this, they succumb to complicated oral adverse effects after radiation therapy. The second last part of this series reviews and discusses the management of complication that commonly occur to the oral mucosa, i.e. mucositis.     

Managing complications of radiation therapy in head and neck cancer patients: Part I. Management of xerostomia

Head and neck cancer is becoming a more recognizable pathology to the general population and dentists. The modes of treatment include surgery and/or radiation therapy. Where possible, pretreatment dental assessment shall be provided for these patients before they receive radiation therapy. There are occasions, however, whereby head and neck cancer patients are not prepared optimally for radiation therapy. Because of this, they succumb to complicated oral adverse effects after radiation therapy. Part I of this series reviews the management of xerostomia. The management of the effect of xerostomia to the dentition/oral cavity is discussed in Part II.     

Osteoradionecrosis

Osteoradionecrosis (ORN) is a severe complication of radiation therapy for head and neck cancer. The current theory in its pathophysiology is thought to be radiation-induced fibroatrophy of the bone. Location of primary tumor, stage of cancer, dose of radiation, oral hygiene, and smoking and alcohol use are risk factors in the development of ORN. Prevention is focused on thorough dental care before, during, and after radiation therapy. Treatment ranges from conservative management with oral rinses and local debridement to radical resection with microvascular free tissue transfer and reconstruction.     

Managing complications of radiation therapy in head and neck cancer patients: Part VI. Management of opportunistic infections

Head and neck cancer is becoming a more recognizable pathology to the general population and dentists. The modes of treatment include surgery and/or radiation therapy. Where possible, pretreatment dental assessment shall be provided for these patients before they undergo radiation therapy. There are occasions, however, whereby head and neck cancer patients are not prepared optimally for radiation therapy. Because of this, they succumb to complicated oral adverse effects after radiation therapy. The last part of this series reviews the opportunistic infections that can occur to the perioral structure. Their management is briefly discussed.     

Managing complications of radiation therapy in head and neck cancer patients: Part III. Provision of dentures

Head and neck cancer is becoming a more recognizable pathology to the general population and dentists. The modes of treatment include surgery and/or radiation therapy. Pretreatment dental assessment should be provided for these patients before they undergo radiation therapy. There are occasions, however, whereby head and neck cancer patients are not prepared optimally and, as a result, they succumb to complicated oral adverse effects after radiation therapy. The management of radiation-induced caries, a sequelae of xerostomia has been reviewed in Part II of this series. In this article, the management of difficulty with dentures, another sequelae of xerostomia following radiation therapy is reviewed.     

An oral disease prevention program for patients receiving radiation and chemotherapy

Thirteen years of treating more than 2,950 patients at the National Institute of Dental Research clinic have shown that a variety of potential oral sequelae associated with cancer therapy can be prevented, reduced in severity, or palliatively alleviated when the dental team has an opportunity to participate in the patient's care. The keystone of this success is based on early referral of the patient for dental consultation, treatment before the initiation of cancer therapy, and a well-defined orientation program to inform patients and their families about the difficulties they may experience. Meticulous attention to oral microbial control, prophylactic use of fluoride gels, and palliative treatment of soft tissue lesions may significantly reduce the oral morbidity associated with radiation and cytotoxic chemotherapy. Diligent personal oral health care and frequent dental recall appointments are recommended for the remainder of the patient's life. It has been our experience that patients who are not followed closely after irradiation therapy have an increased incidence of caries as a result of noncompliance with preventive regimens. The ethical and medicolegal responsibility to fully inform the patient of these recommendations lies with both the medical and dental personnel at the facility providing the radiation-chemotherapy service. The general dentist shares the responsibility for continuity of long-term oral health care.     

A practical guide for patients undergoing exodontia following radiotherapy to the oral cavity

Dental extractions or minor oral surgery in patients who have undergone radiation therapy for cancer in the head and neck carry the risk of one of the most serious and devastating complications of head and neck radiotherapy, that of osteoradionecrosis (ORN). A totally unified approach to dental extractions following radiotherapy is lacking. The role of the general dental practitioner in management of patients following radiotherapy is crucial. Contrary to clinical impression, the risk of ORN does not decrease with time. When contemplating exodontia or minor oral surgery in the irradiated patient, special consideration should be given to issues such as radiotherapy history, surgical assessment, surgical procedure and the role of antibiotics and hyperbaric oxygen.     

Influence of radiation therapy on oral Candida albicans colonization: a quantitative assessment

An increase in quantity of oral Candida albicans was documented in patients receiving head and neck radiation therapy during and after therapy, as assessed by an oral-rinse culturing technique. The amount of the increase was greater in denture wearers and directly related to increasing radiation dose and increasing volume of parotid gland included in the radiation portal. A significant number of patients who did not carry C. albicans prior to radiation therapy developed positive cultures by 1 month after radiation therapy. The percentage of patients receiving head and neck radiation therapy who carried C. albicans prior to radiation therapy did not differ significantly from matched dental patient controls.     

Updated Clinical Considerations for Dental Implant Therapy in Irradiated Head and Neck Cancer Patients

An increasing number of reports indicate successful use of dental implants (DI) during oral rehabilitation for head and neck cancer patients undergoing tumor surgery and radiation therapy. Implant‐supported dentures are a viable option when patients cannot use conventional dentures due to adverse effects of radiation therapy, including oral dryness or fragile mucosa, in addition to compromised anatomy; however, negative effects of radiation, including osteoradionecrosis, are well documented in the literature, and early loss of implants in irradiated bone has been reported. There is currently no consensus concerning DI safety or clinical guidelines for their use in irradiated head and neck cancer patients. It is important for health care professionals to be aware of the multidimensional risk factors for these patients when planning oral rehabilitation with DIs, and to provide optimal treatment options and maximize the overall treatment outcome. This paper reviews and updates the impact of radiotherapy on DI survival and discusses clinical considerations for DI therapy in irradiated head and neck cancer patients.     

A Convenient Method for Guarding Against Localized Mucositis During Radiation Therapy

Metal restorations, such as full gold crowns and dental implants, can cause forward and back scatter radiation during radiation therapy with a dose enhancement to adjacent tissues. Mucositis, one of the most common complications of the radiation treatment of oral, as well as other head and neck malignancies can result. A method for constructing a buccolingual guard in the clinical setting using hydroplastic material is described. The guard can be easily oriented and adapted to an existing radiation stent, adding positional stability and patient comfort. When adequate thickness of material is used, the guard can attenuate forward and back scatter radiation, separate the adjacent tissues from metal restorations, and protect the oral mucosa from localized incidents of mucositis.     

Managing complications of radiation therapy in head and neck cancer patients: Part IV. Management of osteoradionecrosis

Head and neck cancer is becoming a more recognizable pathology to the general population and dentists. The modes of treatment include surgery and/or radiation therapy. Pretreatment dental assessment should be provided for these patients before they undergo radiation therapy. There are occasions, however, whereby head and neck cancer patients are not prepared optimally and, as a result, they succumb to complicated oral adverse effects after radiation therapy. Osteoradionecrosis (ORN) is a severe debilitating condition that impairs healing due to reduction in vascularity and osteocyte population in the affected bone. This article reviews methods of treatment used to treat ORN such as antibiotics, hyperbaric oxygen therapy, therapeutic ultrasound, surgery, and other modalities.     

Oral and maxillofacial side effects of radiation therapy on children

Radiation therapy of the head and neck frequently results in serious and sometimes unavoidable changes to orofacial structures, particularly for children. Acute and chronic complications have a great impact on their oral function and quality of life. This paper provides an overview of the side effects of radiation therapy on children's oral and dental tissues, and highlights appropriate preventive guidelines and management strategies to minimize these complications.     

Long-term success of dental implants in patients with head and neck cancer after radiation therapy

The purpose of this study was to analyze the long-term success and factors potentially influencing the success of dental implants placed in patients with head and neck cancer who underwent radiation therapy with a minimum total dose of 50 Gy during the years 1995–2010. Thirty-five patients (169 dental implants) were included in this study. Data on demographic characteristics, tumour type, radiation therapy, implant sites, implant dimensions, and hyperbaric oxygen therapy (HBOT) were obtained from the medical records and analyzed. Implant survival was estimated using Kaplan–Meier survival curves. Seventy-nine dental implants were placed in the maxilla and 90 in the mandible. The mean follow-up after implant installation was 7.4 years (range 0.3–14.7 years). The overall 5-year survival rate for all implants was 92.9%. Sex (P < 0.001) and the mode of radiation therapy delivery (P = 0.005) had a statistically significant influence on implant survival. Age, time of implantation after irradiation, implant brand and dimensions, and HBOT had no statistically significant influence on implant survival. Osseointegrated dental implants can be used successfully in the oral rehabilitation of patients with head and neck cancer with a history of radiation therapy. Risk factors such as sex and the mode of radiation therapy delivery can affect implant survival.     

Evaluation of a device for attenuation of electron release from dental restorations in a therapeutic radiation field

STATEMENT OF PROBLEM: For some patients, radiation treatment is a part of tumor therapy in the head and neck area before and/or after surgery. The oral cavity and teeth are thereby frequently exposed to high doses of radiation. In this situation, electronic backscatter from dental materials may damage the surrounding soft tissue. PURPOSE: This study determined the degree of absorption and the backscatter effect of therapeutic radiation used in the presence of 4 different dental materials. The efficacy of a protective stent also was investigated. MATERIAL AND METHODS: The influence of 4 dental materials (a high-gold alloy, pure titanium, amalgam, and a synthetic material) on radiation dose distribution was tested on 2 test models that simulated the presence of teeth. An alanine dosimeter was used to make measurements with and without the presence of a protective stent. To verify the results, one of the test models was compared to a computer simulation. RESULTS: Backscatter effects on the surface of dental materials caused an increase of up to 170% of the radiation dose measured without the materials. The rate of overdose increased with the atomic number of the dental material. The extent of the backscatter effect was a maximum of 4 mm. CONCLUSION: The considerable overdose of 170% found in this study suggests that soft tissue surrounding dental restorations should be protected from radiation. The backscatter results indicate that soft tissue could be effectively shielded with a 3-mm synthetic stent.     

The role of dentistry in head and neck radiation therapy

In the adult patient, oral complications of cancer radiotherapy stem from the deleterious effects of radiation on salivary glands, oral mucosa, mandibular musculature and alveolar bone. Clinical consequences of such treatment include xerostomia, rampant dental decay, mucositis, taste loss, osteoradionecrosis, infection, trismus, and nutritional stomatitis. These alterations to the normal state occur both during and after completion of head and neck radiation. Fig. 1 outlines the time frame involved in the development of each particular problem. In the past 20 years, many changes have occurred in the management of patients receiving radiation therapy. The traditional regimen of dental care in these patients was one of extracting all teeth encompassed by the radiation field. However, 15 years ago, this concept was questioned due to the incidence of post radiation caries (PRC) outside the zone of irradiation. The purpose of this paper is to review the major consequences of radiation treatment to the head and neck as well as outline the role of the dentist in the management of these patients.     

Management of the oral sequelae of cancer therapy

Oral cancer and the oral sequelae of treatment for oral and other malignancies can significantly affect a patient's oral and systemic health, as well as have a profound impact on quality of life. Compromised oral health prior to, during, and following cancer therapy can affect treatment outcomes. Increasingly, dental professionals in the community are being called upon to provide care for these individuals. Radiation therapy is routinely used for tumors of the head and neck, delivering a concentrated radiation dose to the tumor, but also to the immediately surrounding tissue. Oral complications are related to the site radiated and the total radiation dose. Cancer chemotherapy is provided as a primary treatment for some cancers and as an adjunctive modality for other cancers. The goal is to eradicate the rapidly growing cells of the tumor, but chemotherapy is often toxic to other cells that rapidly divide normally including the oral mucosa. The use of combined chemotherapy and radiation is now considered standard for most locally advanced tumors of the head and neck. The toxicities of this combined therapy are essentially the same as with radiation alone, but develop more rapidly and are typically more severe when they reach maximum level. The most common oral sequelae of cancer treatment are: xerostomia, the sensation of a dry mouth as a result of damage to the salivary glands and/or medication; mucositis, the inflammation and ulceration of the oral mucosa; and infection as a result of the loss of mucosal integrity. Management of oral health during cancer therapy includes identifying at-risk patients, patient education, appropriate pretreatment interventions, and timely management of complications. Appropriate preventive and therapeutic measures will help minimize the risk of oral and associated systemic complications, improve treatment outcomes, and improve the patient's quality of life.     

Oral Kaposi sarcoma associated with severe alveolar bone loss: case report and review of the literature

BACKGROUND: In AIDS patients who present with an oral neoplasm, Kaposi sarcoma is the tumor most frequently encountered, comprising 50% to 80% of all tumor occurrences. However, oral Kaposi sarcoma associated with erosion of underlying bone is a relatively rare finding. This report and review of the literature documents a case of AIDS-related oral Kaposi sarcoma exhibiting severe bilateral erosion of the maxillary alveolar ridges. METHODS: An HIV-seropositive male with extensive maxillary Kaposi sarcoma and associated bilateral alveolar bone erosion presented for dental evaluation subsequent to radiation therapy. Clinical and radiographic examinations were performed. Medical and dental histories were procured and supplemented with consultations from the patient's primary physician and radiation oncologist. Maxillary edentulation with surgical revision for primary closure was the treatment of choice for management of the dentoalveolar pathology. A maxillary immediate treatment denture was designed to obturate anticipated antral communications with the maxillary sinus. RESULTS: Surgical and prosthetic treatments were completed, but complicated by an oral-antral perforation that subsequently healed without complication. Soft tissue biopsies obtained during surgery revealed no evidence of residual Kaposi sarcoma. CONCLUSIONS: Although AIDS-related oral Kaposi sarcoma is a relatively common finding, erosion of subjacent alveolar bone is uncommon. Treatment of the tumor with subsequent dental reconstruction can be complicated by the severe lack of bone, surgical perforation of the maxillary sinus, and lack of stable teeth to serve as abutments. Significant advances in understanding the pathogenesis of AIDS-related Kaposi sarcoma have occurred in the last decade. HHV-8 and various inflammatory cytokines have been implicated in the pathogenesis and are likely to become the primary targets for therapeutic intervention.