Prosthetic treatment and rehabilitation: Use in patients with cancer of the head and neck

PROSTHETIC TREATMENT AND REHABILITATION' USE IN PATIENTS ~VITH CANCER OF THE HEAD AND NECK i

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ALAN J. HICKEY, D.M.D. 'JOE B. DRANE, D.D.S.

0147-0272/78/0011-0001505.00 9 1978 Year Book Medical Publishers, Inc.

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TEAM CONCEPT OF PATIENT CARE

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ROLE OF MAXILLOFACIAL PROSTHODONTIST

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REHABILITATION OF THE CANCER PATIENT

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SURGICAL VS PROSTHETIC REHABILITATION .

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GENERAL SURGICAL AND PROSTHETIC CONSIDERATIONS . . . . .

Functional and Emotional Deficiencies . . . . . . . . . . Other Therapeutic Modalities . . . . . . . . . . . . . Surgical Considerations . . . . . . . . . . . . . . . SPECIFIC DEFECTS AND PROBLEMS FOR CONSIDERATION . . . . .

Intraoral Defects . . . . . . . . . . Extraoral Defects . . . . . . . . . Intraoral-Extraoral Defects . . . . . . Alloplastic Implants . . . . . . . . SUMMARY

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is a senior resident in maxillofacial prosthetics at the University of Texas System Cancer Center, M. D. Anderson Hospital and Tumor Institute, Houston. Dr. Hickey received his D.M.D. from the University of Pittsburgh. He completed a rotating internship at MoncriefArmy Hospital and spent three years as Clinic Chief of the U.S. Army Dental Clinic in Bad Hersfeld, Germany. Currently, Dr. Hickey is doing research in the oral complications of chemotherapy in the treatment of cancer.

is Professor and Head of the Department of Dental Oncology at the University of Texas System Cancer Center, M. D. Anderson Hospital and Tumor Institute. He is also Professor of Restorative Dentistry-Maxillofacial Prosthetics at the University of Texas Health Science Center Dental Branch, Houston. He received his D.D.S. from Texas Dental College and Certificate in Maxillofacial Prosthetics from the University of Texas, M. D. Anderson Hospital. Dr. Drane is past president of the American Academy of Maxillofacial Prosthetics. His research interests include maxillofacial prosthetics and the development of comprehensive dental programs for the management of oral complications in cancer patients.

T R E A T M E N T OF CANCER in the head and neck region is often debilitating aesthetically, functionally and emotionally. As b etter and more effective techniques in surgery, radiotherapy and ch emo th er a py or combinations t h e r e o f are developed, the life expectancy of the patient with cancer of the head and neck is often m a r k e d l y increased. Thus, rehabilitation of these patients has become increasingly i m p o r t a n t in enabling the patien t to continue, as closely as possible, the life-style to which he had been accustomed before t r e a t m e n t . 3

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Many persons in a wide range of disciplines are involved in the treatment and rehabilitation of the patient with cancer of the head and neck. An ever-increasing role is being played by the maxillofacial prosthodontist in this care. At M. D. Anderson Hospital and Tumor Institute (Houston), the case load in the department of dental oncology has increased dramatically as the importance and value of dental care have been recognized and implemented in the overall treatment of the patient with cancer I (Figs I and 2). Many initial diagnoses of cancer of the head and neck are made by general dentists. Ifa lesion can be found early when it is small and localized and has not metastasized, the prognosis for the patient is greatly improved. The general dentist can help greatly in the early detection of the cancer and in screening for recurrence of residual disease. Improved communication between physicians and dentists is sorely needed and has been emphasized by Condit Moore, M.D. (in his presidential address at the annual meeting of the Society of Head and Neck Surgeons in April, 1976)3 This article deals mainly with prosthetics in patients with can4

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cer who undergo surgery of the head and neck, but the equally important roles of the maxillofacial prosthodontist are briefly discussed in relation to patients receiving irradiation therapy to the head and neck areas or chemotherapy for a malignancy in any area of the body.

TEAM CONCEPT OF PATIENT CARE The need for specialized dental care for the patient with cancer of the head and neck is extraordinary and often unrecognized. A disease so complex requires the team approach in a long-term treatment and rehabilitation plan if the patient is to resume normal activity. This team might ideally consist of the primary care physician, surgeon, radiotherapist, maxillofacial prosthodontist, pathologist, diagnostic radiologist, nursing staff and medical social worker. The primary care physician often makes the initial diagnosis and is frequently involved in much of the follow-up care. Followup care can be particularly challenging and difficult because facilities may be limited and the primary care physician may not be familiar with the problems encountered by the patient with cancer. The pathologist and diagnostic radiologist are invaluable in determining the type of disease and its limitations. At M. D. Anderson Hospital, the surgeon responsible for the head and neck regions has ultimate responsibility for the treatment of the patient with cancer in these areas and makes the final decision on the plan of treatment, which may combine the modalities of surgery, radiotherapy and chemotherapy. The maxillofacial prosthodontist has an important role in the planning, treatment, and 5

rehabilitation of the patient with cancer. During the surgical phase, he is re=ponsible for developing treatment prostheses such as immediate .~bturators and implants; during radiotherapy, stents, posiSi(. =ers and management of oral complications; and during ch~-~_,-therapy, pretreatment evaluations and management of orm complications. The medical social worker helps patients cope with their disease, the unfamiliar hospital situation and related family and social problems. One of the problems that often occurs is that each specialist has a tendency to look at the patient's problems with an emphasis on that health professional's training and interest. This team concept has several advantages. The experience of each specialist can be considered and used to the best advantage for optimal overall treatment of the patient. "A better understanding of the patient's disease process and its extent can be evaluated, and consideration can be given to each of the treatment modalities. Short- and long-term rehabilitation goals as well as individual patient factors also can best be evaluated. Unfortunately, there are many problems that must be solved before providing the necessary dental care to the patient with cancer of the head and neck. At the present time, the need for this type of service is tremendous, but the demand is not, for a number of reasons. The teaching of maxillofacial prosthetics in both medical and dental schools is either totally lacking or minimal. The physician occasionally perceives, quite falsely, the prosthodontist as a threat, when in actuality the prosthodontist is another member of the treatment team and can greatly aid the physician in the comprehensive care of the patient. Many treatment centers are unwilling to adequately finance a dental department, often because they are unfamiliar with the benefits to be gained by both the hospital and the patients. The availability of welltrained professional and auxiliary individuals in this field is limited. All these problems revert to one basic p r o b l e m - a need for better communication among and education for the physicians, the dentists and the public.

ROLE OF MAXILLOFACIAL PROSTHODONTIST The maxillofacial prosthodontist often sees the patient with cancer of the head and neck more frequently during the rehabilitative phase than does the physician; therefore, he is familiar with the oral and systemic condition of the patient. He is in a position to work closely with the physician in the prevention or minimization of complications and in possible early detection of recurrent disease. With advance rehabilitation planning, unfavorable postsurgical tissue contours can often be avoided, Without compromise treatment for the cancer. Through this cooperative effort, the physician can also become familiar with the prob6

lems faced by the prosthedontist. This will be discussed later at greater length. Infection is a constant problem in management of cancer, and the risk greatly increases with many types of treatment. Frequently, infections classified by the physician as infection of unknown origin (IUO) originate from the oral cavity. A chronic oral infection, which would normally have little effect, can progress rapidly when the natural defenses of the patient with cancer have been impaired or destroyed by chemotherapy, irradiation or surgery. Many patients with cancer of the head and neck are heavy smokers and drinkers and may have extremely poor oral hygiene habits, related periodontal disease and caries. In periodontal disease, the gingival sulci around the teeth become huge reservoirs for bacteria and potential infection, which can be reduced sharply by scaling of the teeth and prophylactic treatment before surgery, chemotherapy or radiotherapy. When periodontal disease is advanced or caries is extensive, particularly to the point of forming periapical abscesses, it may be necessary to extract selected teeth. Oral sequelae must be considered when a patient is to receive irradiation to the head and neck region, either as a sole modality or in combination with surgery or chemotherapy. Because radiation to these areas destroys salivary gland function, thereby reducing salivary flow into the oral cavity, eating and swallowing may become difficult for the patient. Caries is often prevalent in irradiated patients if the teeth are not properly protected with fluoride after treatment. Healthy teeth should not be extracted even if they are directly in the field of radiation. They can be Fig 3 . - I n lower section of figure, maxillary and mandibular casts have been poured in dental stone and trimmed; fluoride carriers are constructed (upper section).

maintained in good condition if the patient is placed on a daily fluoride program with conscientious follow-up. At M. D. Anderson Hospital and Tumor Institute, impressions of the maxillary and mandibular arches are made with irreversible hydrocolloid, and fluoride carriers are constructed of mouthguard material* (Fig 3). These carriers are given to the patient with instructions for use with a special 1% sodium fluoride gel~ for at least five minutes per day after cleaning the teeth. Because of the permanent reduction of quantity and quality of salivary flow, this procedure must be followed daily for the rest of the patient's life. Daily application of this fluoride gel also prevents increased sensitivity of exposed root surfaces of the teeth, another frequent side effect of irradiation. Caries associated with radiation therapy should be a thing of the past with a well-run fluoride application program and patient cooperation. If possible, nonrestorable teeth should be extracted at least two weeks before the start of irradiation. These teeth should not be extracted after radiotherapy has begun because of the increased chance of developing osteoradionecrosis. As the dose of radiation increases, the probability of developing osteoradionecrosis and other complications increases3 (Tables 1 and 2). TABLE 1.-DOSE-RELATED INCIDENCE OF DECAY AFTER IRRADIATION, hi. D. ANDERSON HOSPITAL AND TUMOR INSTITUTE (JANUARY 1966-JUNE 1972} TOTALS I N T E N S I T Y OF RADIATION DOSE

PATIENTS TREATED

0000-2000 2000-3000 3000-4000 4000-5000 5000-6000 6000-6500 6500-7000 Over 7000 TOTALS

6 2 4 6 27 32 34 23 134

RADIATION DECAY

1 2 3 16 20 14 11 67 (50%)

Note: Of 134 dentulous patients who received radiation to salivary gland areas, 67 (50%) developed radiation decay. Patients who developed decay after irradiation were either randomly separated to groups that received no fluoride treatment or did not use prescribed fluoride. Adapted from Daly, T. E., and Drane, J. B.: Management of dental problems in irradiated patients. Annual meeting of the Radiological Society of North America, Chicago, November 26- 29, 1972. *STA-Guard Mouthguard Material, Buffalo Dental Manufacturing Co., Brooklyn, NY 11207. J'Emerson Laboratories, Dallas, TX 75221. 8

TABLE 2.-NECROSIS RELATED TO TUMOR DOSE, M. D. ANDERSON HOSPITAL AND TUMOR INSTITUTE (JANUARY 1966-JUNE 1972) I N T E N S I T Y OF RADIATION DOSE

0000-2000 2000-3000 3000-4000 4000-5000 5000-6000 6000-6500 6500-7000 Over 7000 TOTALS

RATIO TO P A T I E N T S TREATED

1/14 1/6 0/8 1/9 12/47 26/77 13186 13/57 67/304

(7%) (16%) (0) (11%) (25%) (28%) (15%) (22%) (22%)

Note: Of 304 patients treated with radiotherapy to head and neck area, 67 (22%) developed necrosis. There is an increased incidence above 6000 rad tumor dose. The statistics, however, do not reflect this because of early death due to disease. Adapted from Daly, T. E., and Drane, J. B.: Management of dental problems in irradiated patients. Annual meeting of the Radiological Society of North America, Chicago, November 26-29, 1972.

The effects of radiation are progressive and persist throughout the lifetime of the patient. There have been m a n y instances of osteoradionecrosis developing eight to nine years after radiotherapy was completed. Although osteoradionecrosis can occur in either the mandible or the maxilla, it is more common in the mandible. Radiation will cause a permanently reduced blood supply in both soft tissue and bone, which can result in spontaneous osteoradionecrosis or osteoradionecrosis precipitated by a traumatic episode. Radiated soft tissue can also often become fibrotic and nonelastic. Some of these complications can be reduced by using an acrylic and metal* stent or shield to protect tissues during treatment where irradiation is not needed. For example, a stent could displace and protect the tongue during irradiation of a lesion of the buccal mucosa. The effectiveness of the cancer treatment in this instance would not be compromised. Acrylic positioners to displace tissue into desired locations can also be constructed; for example, in treating a large lesion of the tongue with parallel opposed fields, a positioner can displace the tongue downward onto the floor of the mouth and separate the maxillary and mandibular arches to avoid radiation to the maxillary arch. In irradiating the tongue, there are disadvantages to the use of corks as positioners to which tongue blades have been taped. This often permits the tongue to roll up on the sides and behind the blades, *Cerrobend Alloy, Metal Goods Corp., Houston, TX 77033

.~Ton~ue gue~~ngue

Fig 4 . - A , corks placed as separators and positioners allow tongue to roll up on lateral borders because tongue blades in the posterior part of the mouth are not wide enough. The tongue can also hump up in back because of inadequate blade length. Even though cork is notched on the superior surface, it can easily rotate and make it difficult to obtain reproducible positions. Stents or positioners such as the one in B are keyed exactly to existing teeth or edentulous ridges, making them stable. The prosthesis keeps the tissue in place in easily reproducible positions, facilitating accurate radiation delivery. It reduces gagging, does not absorb saliva in mouth that may be dry and have mucositis secondary to radiation and is more stable than cork. Patient is able to insert prosthesis, thereby reducing set-up time.

which can result in missing those areas of the tongue that should remain in the field. To compensate for this, the size of the field must be increased, resulting in radiation of unnecessary tissue (Fig 4). The advantage of using stents and positioners is the accurate reproducibility of the position of the tissues to be radiated, which results in a more accurate delivery of radiation and in reduction of set-up time, allowing treatment of more patients per day. The prosthodontist constructs the prosthesis after consultation with the radiotherapist and he is also responsible for instructing the patient on the use and insertion of the device. After radiation, the tissue is much more likely to disintegrate, and each patient should be evaluated on an individual basis before any prosthetic appliance is constructed. Dentures can be successfully constructed for many patients treated with radiation, but extra care must be used in the construction of these prostheses, with close follow-up after insertion. If soft tissue necrosis and osteoradionecrosis occur locally, management is accomplished using conservative techniques as described by Daly and Drane. 3 Chemotherapy can also greatly alter the oral tissue response in patients. For patients receiving chemotherapy there is a sharply increased risk of developing infection because of extreme myelosuppression. In 1966, Bodey et al. 4 reported that there is a direct correlation between severity of myelosuppression and infection in 10

patients with acute leukemia. Many of these infections m a y originate in the oral cavity. This potential danger could be reduced by debriding and cleaning the oral cavity and extracting abscessed teeth before the initiation of treatment. Chemotherapy can also cause spontaneous soft tissue breakdown in the oral cavity, with resulting bone exposure, especially in thin, soft tissue areas, such as those over mandibular tori. Severe stomatitis is a complication resulting from the use of some chemotherapeutic drugs. There seemingly is a direct correlation between the severity of stomatitis and the quality of the patient's oral hygiene. In a study of patients with breast cancer who received 5-fluorouracil, adriamycin and cyclophosphamide, which is the FAC regimen, 5 it was demonstrated that the severity of stomatitis decreased as the initial oral hygiene improved. With some protocols, such as velban and bleomycin (VB 3) used in treating testicular carcinoma with metastasis, stomatitis can be a limiting factor in dose escalation and can become so severe that the patient is unable to swallow even his own saliva. This becomes a severe m a n a g e m e n t problem affecting the nutritional status of the patient and making pain control difficult. With a breakdown of the intact oral mucosa, there is an increased probability of local infection in the oral cavity spreading to deeper structures. More research in this area is greatly needed.

REHABILITATION OF THE CANCER PATIENT Because patients with cancer are living longer, rehabilitation is of prime importance. Patients are often cured of their disease but are unable to resume normal relationships with family, friends, co-workers or society in general. For many years, concerned individuals have attempted to restore lost facial areas with prostheses when surgical repair was either impossible or undesirable. Ambroise Par~ (1517-90), the famous French surgeon, was the first to write extensively on prosthetic reconstruction. He described maxillary obturators and nasal prostheses that he had constructed and placed successfully on patients. Most of these devices were constructed of metal and were retained with strings, bands and locking devices. Pierre Fauchard (1678-1761) was another pioneer in this field, and his publications described several ingenious maxillofacial prostheses. Many of the basic principles he proposed are still used today. More advances were made in the 18th and 19th centuries, b u t m a n y of the early researchers were limited by the availability of materials. V. K. Kazanjiam, D.D.S., of Boston renewed interest in maxillofacial prosthetics by using vulcanite as a reconstructive material. G Presently, new and improved materials such as polyvinylchloride, urethane and silicone are commonly used for extraoral prostheses, b u t these materials do have some deficiencies. Acrylic 11

resin (methylmethacrylate) and chrome-cobalt are excellent materials for intraoral reconstruction. There are multiple factors to be considered in rehabilitation of the patient with cancer of the head and neck. It is not enough to repair only the surgical defect; the function of the tissue and the aesthetics of the surgical or prosthetic repair are important considerations for the patient. The stressing of rehabilitation as well as cure of the disease will greatly enhance the patient-physician relationship. It is here that the prosthodontist can aid the physician. In m a n y instances, the physician's task can be made easier by utilization of prosthetic reconstruction, such as immediate surgical obturators placed at the time of surgery. 7 A quick recovery can improve the patient's morale by returning him to as normal a daily schedule as possible. Return to work can ease the financial burden and often improve the patient's self-image.

SURGICAL VS PROSTHETIC REHABILITATION The area of surgical and prosthetic rehabilitation always seems to be controversial. Actually, the physician and the prosthodonfist are not competing. When feasible, usually it is better to do a surgical repair than a prosthetic repair, although each patient's situation should be evaluated on an individual basis and his general health taken into consideration. Can this patient tolerate the physical and emotional stress of the operation and the recovery period? Is the patient a good anesthetic risk? (Many patients with cancer of the head and neck are not, because of complicating factors such as emphysema or liver malfunction.) If not, an alternative to surgery should be considered. The cost and time involved in multiple plastic procedures, hospitalization, operating room costs, physicians' fees and time lost from work must be weighed. The aesthetic result obtained from prosthetic reconstruction is sometimes superior to surgical repair, especially with ear and nasal replacements. The defect can be so extensive that complete surgical repair is impossible and an alternative is necessary. Often, interim appliances are necessary between surgical procedures or to act as stents to facilitate surgical repair. Occasionally, the surgical area requires a long observation period to check for possible recurrence of disease and rate of healing. In this instance, a removable prosthetic appliance can cover the surgical defect and provide interim repair. When evaluating the type of repair to be used, it is important to consider the patient's attitude and desires. Alternative types of reconstruction should be presented to the patient so that, after consideration of all factors, the best one can be selected. 12

GENERAL SURGICAL AND PROSTHETIC CONSIDERATIONS An aspect of prime importance before treating any patient with cancer of the head and neck is adequate and thorough advance planning. Before surgery, the physician and prosthodontist, preferably together, should determine the proposed extent of the postsurgical defect, the type and time sequence of treatment and rehabilitative considerations for each patient. Presurgical records, including impressions of the tissue contours before surgery, presurgical roentgenograms, jaw relationship records and photographs, are often found to be invaluable after surgery, and they should be obtained during the planning phase. FUNCTIONAL AND EMOTIONAL DEFICIENCIES

Functional deficiencies that may result from surgery, that is, tissue loss, fibrosis or neurologic damage, must be evaluated, planned for and explained to the patient beforehand. These deficiencies should be minimized as much as possible through surgery and prosthetic repair. The specific problems associated with each defect will be discussed later, but at this point we discuss some of the general considerations involved. 1. Speech is often greatly altered by surgery in the area of the oral cavity, especially with surgery of the tongue, the hard and soft palate and the floor of the mouth. These alterations or loss of speech become especially important to the illiterate patient who is unable to communicate by other means. 2. If the patient is unable to swallow or eat after surgery, he may require a permanent nasogastric tube. Maintaining adequate nutritional status in this situation is difficult. Aspiration and its concomitant complications at times can result from these functional deficiencies. If the patient undergoes a total glossectomy, it is often necessary to perform a laryngectomy to prevent repeated aspirations even though the larynx is not involved with tumor. 3. Oral incompetency, or the inability to control and contain one's saliva, is one of the functional problems most annoying to a patient, and one that can create extreme emotional frustration. This is a common problem in patients who have had extensive surgery of the lips or mandibular resections. 4. The importance of maintaining sound teeth cannot be overstressed. This factor alone can often determine whether a successful reconstruction is possible. Natural teeth can add significant retention and stability to maxillary obturators and other prosthetic appliances used to repair surgical defects. In patients who require a partial resection of the mandible, natural teeth greatly aid in mastication and in maintaining intact arch relationships. 13

Fig 5 . - D y n a m i c mus and fibrosis.

bite opener in use on patient with radiation-induced tris-

5. Tissue fibrosis, whether caused by surgery or irradiation, can noticeably alter relationships of soft tissue and bony structures such as the maxillary and mandibular arches. Trismus can cause severe pain, as well as functional disability. These problems can often be reduced with a conscientious exercise program and good postsurgical stabilization to reduce deviation of the mandible that results from scar contracture and fibrosis. Sometimes the problems can be corrected later by exercise with equipm e n t such as the "dynamic bite opener" (Fig 5). When surgery or irradiation in the head and neck area is necessary, the patient m a y experience a wide range of emotional conflicts. He wishes to be cured of his cancer, yet he is concerned about disfigurement. The aesthetics of this visible area can be a major rehabilitative obstacle. The importance of aesthetics varies greatly from patient to patient, depending on such factors as social position, occupation, family support, self-image, vanity and age. Many times, patients have unrealistic expectations of the surgical or prosthetic rehabilitation and do not anticipate the limitations involved. In severe cases, loss of time from work and the disfigurement resulting from t r e a t m e n t can lead to financial and social difficulties. Social interaction with family and friends is often affected by the visual and functional changes in the pal4

tient's features. A positive and supportive outlook by family, friends and medical staff can make dramatic changes in the rate of recovery for many patients. OTHER THERAPEUTIC MODALITIES There are other treatment modalities used alone or in combination with surgery that affect the overall treatment plan for the patient. Radiotherapy can alter greatly the tissue response because of decreased blood supply and fibrosis in the affected area, and can result in poor healing and both hard and soft tissue breakdown. Osteoradionecrosis is a constant hazard during and after radiotherapy. The altered salivary flow that commonly results from radiotherapy of the head and neck area can create discomfort for the patient and difficulties in prosthetic reconstruction. Saliva normally acts as a lubricant between the prosthesis and the tissue, but when this salivary flow is diminished or absent the prosthesis may tear and abrade the mucosa. For this reason, extra care must be taken with the impression materials and denture construction. Conscientious follow-up after insertion is necessary to minimize potential complications. Eating also can be difficult because the oral cavity lacks fluids to moisten the food and aid in swallowing. Several artificial saliva preparations such as Oralube,* are available2 Another complication of radiotherapy is the development of severe mucositis during treatment, which necessitates discontinuing the use of any prosthesis because of potential tissue breakdown. Severe pain and eating problems may accompany mucositis, which is usually treated symptomatically with topical anesthetics, oral rinses and tissue protectors. Patients undergoing chemotherapy for cancer also require specialized dental care because of the complications of immunosuppression, myelosuppression, stomatitis, infection and altered tissue response in the oral cavity. The timing sequence for the necessary dental care must be coordinated with the patient's chemotherapy regimen to avoid complications. Other related medical conditions, such as anemia, diabetes and heart disease, also must be evaluated as to their effect on the surgery and later rehabilitation. SURGICAL CONSIDERATIONS

After consultation with other specialists, as definitive a surgical plan as possible should be developed before surgery, taking *Oral DiseaseResearchLaboratory,VAHospital, Houston,TX77030. 15

into account the removal of the tumor and the immediate and long-term reconstruction of the defect. The extent of the tumor is, of course, the deciding factor in the size of the surgical defect, b u t placement of the surgical margins can be critical in later reconstruction, especially in maxillary and mandibular resections (this is discussed later). Often, the surgeon will retain as much tissue as possible when a prosthetic reconstruction is to be used; however, it is often more desirable to remove certain tissues for adaptation and contouring of the prosthesis and a proper fit. It is important to determine the time sequence of rehabilitation: immediate (surgery during primary treatment), short-term (one to three weeks), or long-term (indefinite). The complications of fibrosis, deviation and trismus can be reduced if the remaining tissues can be stabilized, especially in partial mandibular resections. Close follow-up by the surgeon and prosthodontist is an essential part of the treatment plan.

SPECIFIC DEFECTS AND PROBLEMS FOR CONSIDERATION In the remainder of this article, we discuss specific surgical defects and their surgical and prosthetic considerations. These will be classified into four basic categories: (1) intraoral (mandibular, maxillary and combination), (2) extraoral, (3) intraoral-extraoral and (4) alloplastic implants. INTRAORAL D E F E C T S Mandibular Intraoral defects in the mandibular area are commonly caused by cancer of the tongue, floor of the mouth, gingival tissue, lips, cheeks, tonsillar pillars, retromolar trigone area or mandible. Of course, the size of the primary lesion and its metastatic spread will determine the extent of the resulting defect. As the size of the lesion increases, the prosthetic and rehabilitative prognosis becomes poorer. SOFT TISSUE.-- If a lesion is small and is confined to the soft tissue in the mandibular area, the resulting disability is minimal and often transient. The tongue is a common area for developm e n t of malignant intraoral lesions, and a partial glossectomy is often necessary. This procedure can cause limitations in the range of motion in the tongue because it alters anatomy and innervation and results in tissue loss, scar formation and soft tissue closure problems. When the cheek has been sutured to the remaining tongue, speech, swallowing and control of saliva, as well as the ability to wear any type of prosthetic appliance, can be 16

impaired. If a skin graft is used to close the area, the tongue may be kept free and functional difficulties can be reduced. When the tongue is sutured to the remaining mandibular ridge, similar problems are encountered. These, again, can be reduced with skin grafting and recreation of normal sulci. If a large bulk of tongue tissue is removed with the tumor, the patient may not be able to contact the palate area with the tongue, which creates difficulties in swallowing and speaking. Vocal sounds are usually not greatly affected by a partial glossectomy, but there can be severe distortion of consonant sounds. Anterior tongue restriction can cause distortion of sounds, such as "d" and "t," whereas "g" and "k" will be adversely affected by posterior tongue restriction. 9 The palate can sometimes be lowered prosthetically to facilitate contact and improve deglutition and speech. Lesions of the floor of the mouth can create similar problems to those encountered with a partial glossectomy, as well as the inability to raise the floor of the mouth to allow the tongue to make palatal contact in speech and deglutition. If the tongue is used to repair the floor of the mouth or if cheek flaps are swung down for Fig 6 . - I n t r a o r a l view of tongue, floor of mouth (d), and left buccal mucosa (c). In this patient bilateral cheek flaps were used for closure of lesion of anterior mandibular ridge. There is continuous movable soft tissue from lower lip to undersurface of tongue, which also obliterates all sulci. A scar band (b) in posterior area (seen on the left) crosses the ridge from the cheek area into the floor of the mouth. Tongue movement is also restricted. These factors create a poor base for any prosthesis because of lack of stability of tissue and poor tissue contour. The only area for stability is retromolar pad area (a). Compare with Figure 9, in which skin graft was used for closure and resulted in less disability.

.~--.- r

17

closure, the anatomic structure is greatly altered (Fig 6). This creates a poor tissue base for any type of denture and may make it impossible for the patient to successfully wear these appliances, because of loss of stability. If sound, natural teeth remain, however, they can greatly help in retention and stabilization of the prosthesis. If surgery is necessary on the lower lip and oral competency cannot be obtained, the resulting disability is a constant annoyance and problem to the patient. Sometimes this problem can be reduced by improving lip support with a prosthesis to better contain the oral fluids. When lesions develop on the cheek and other mandibular soft tissue areas, the disability is less but there is some alteration in anatomy and function. The overall prosthetic prognosis is good in soft tissue defects that are not extremely extensive and in which good primary surgical repair has been accomplished. The patient should, therefore, be encouraged to undergo this type of prosthetic repair. CORONAL OR MARGINAL RESECTION. - - W h e n a coronal or marginal resection of the mandible is necessary along with some soft tissue removal, the cancer is usually either next to the bone or superficially invasive into the bone. Every effort should be made to retain mandibular continuity. At this institution, many coronal, marginal and step-down procedures are performed to keep the mandibular arch intact (Fig 7). As much function as possible is retained because jaw deviation is eliminated and jaw relationships are maintained. There is a much less visible defect, which helps the patient's emotional state. Sometimes the remaining mandibular arch can be strengthened and aesthetics improved by

Fig 7.-Cross section of mandible, showing possible cuts for step-down procedure. This procedure can be used if carcinoma is not deeply invasive in mandible. It retains mandibular integrity and reduces postoperative complications.

Res~ ec/ed

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Re/e/ned

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Fig 8 . - A , intraoral view of anterior floor of mouth after resection of squamous cell carcinoma by mandibular coronal resection; skin graft was placed for closure. Tongue function was not impaired, and stable base for prosthesis was established. If tongue had been sutured to lip or to ridge for primary closure, disability would have been greater and prosthetic prognosis poorer. A cast chrome-cobalt mandibular partial was constructed to strengthen mandible and reduce possibility of mandibular fracture. B, intraoral view of the same patient as in A. Mandibular partial in place with chrome-cobalt framework and acrylic teeth. This not only strengthens mandible but improves aesthetic quality and helps to retain food in proper location for mastication.

a removable partial denture, if sound teeth remain on either side of the defect (Fig 8). When a partial mandibular resection is performed and the arch integrity is not maintained, oral competency, function and aesthetics can be compromised. If the teeth remain, one surgical consideration is the placement 19

| Correct

Incorrecl

Fig 9 . - I f teeth remain in mandible or maxilla, the line of resection should be through the depth of next tooth socket to retain adequate bone around remaining teeth. It is better to extract one additional tooth and go through depth of that socket than to cut along tooth, thus destroying interdental bone.

of the lines of resection. The desired line of resection is through the depth of the socket in the alveolar bone after that tooth has been extracted (Fig 9), thus leaving interdental bone support around the remaining teeth. If the cut is made just anterior or posterior to a tooth, that tooth becomes weak and may be lost later, thus interfering with prosthetic reconstruction or surgical repair. It is better to extract an additional tooth and resect through that alveolar socket than to try to retain an extra tooth with the surgical margin adjacent to it. Again, later reconstruction is greatly aided if suturing of the tongue or floor of the mouth to the lip or cheek can be avoided. The overall prosthetic prognosis here is fair to good, depending on the extent of the defect, the number of remaining natural teeth and the same general soft tissue considerations as were discussed previously. MANDIBULAR R E S E C T I O N . - - When cancer of the mandibular area progresses and invades extensive osseous tissue, a mandibular resection is often necessary. The most common types of resection are: (1) unilateral resection of the body and ascending ramus with the anterior margin posterior to the cuspid regions on the resected side, (2) resection of the body and ascending ramus-condyle area on one side to the opposite cuspid region and (3) resection of the anterior mandible with two posterior fragments remaining. All these procedures can be debilitating because of the interruption of function and aesthetics. Swallowing, speech, mandibular movements, mastication, control of saliva, respiration and psychic functioning are adversely affected by radical mandibular surgery. 10The relationship of the maxilla to the mandible is often grossly affected after surgery. The more extensive the resection, the poorer the prosthetic rehabilitative prognosis; however, thorough advance surgical and prosthetic planning can reduce some of the complicating factors. If at all possible, a marginal resection should be performed to maintain arch integrity. One problem associated with all mandibular resections is postsurgical deviation and rotation of the remaining fragments. Usu20

ally the distal fragments move medially and downward, which interferes greatly with aesthetics, function and prosthetic rehabilitation. Because of scar formation, tissue contracture and healing, the most rapid deviation occurs in the first three to four weeks immediately after surgery. This problem can be greatly reduced with good postsurgical immobilization; if an adequate number of teeth remain, arch bars can be placed and the jaws immobilized with intermaxillary wiring or elastic bands. An interocclusal wafer can often be of tremendous help in keying the occlusion. When the patient is edentulous, or has few remaining teeth, gunning splints can be fabricated before surgery and wired into place with circumzygomatie, anterior nasal spine and cireummandibular wiring for stabilization. The arch bars that have been previously embedded in the acrylic resin are used for the intermaxillary fixation (Fig 10). This immobilization for three to four weeks after surgery reduces malpositioning of the mandible in relation to the maxilla. Instructing the patient in postsurgical mandibular exercises will help maintain a good range of motion and reduce these complications. Patient motivation must be constantly reinforced during the recovery phase. If an adequate number of teeth remain for stabilization, a resection appliance can be constructed to aid the patient in realigning the remaining mandibular fragments with Fig l O . - G u n n i n g splints mounted on articulator on stone casts made from presurgical impressions of patient's dental arches. Patient required mandibular resection because of bony invasion of squamous cell carcinoma into right body of mandible. Immediate reconstruction with alloplastic implant was done. Gunning splints were used not only for stability but to obtain correct mandibular-maxillary relationship, which had been established from presurgical records.

21

Fig 1 1 . - A , intraoral view of patient with mandibular resection on left side. Note deviation toward resected side and patient's inability to obtain proper occlusion. Patient had great difficulty eating because of lack of tooth contact. B, intraoral view of patient in A with resection appliance in place. Appliance is extended as far as possible into vestibule area so that he does not disengage prosthesis on opening mouth. Left side of occlusion is still not in total contact because of rotation of remaining mandible. Lateral placement of mandibular arch is overcorrected to allow some relapse when use of appliance is discontinued.

the maxilla. Often the patient learns the correct position rapidly and no longer needs to use the resection appliance after the training period (Fig 11). The most debilitating type of resection is loss of the anterior section of the mandible. Oral competency resulting from a lack of lip support is almost always a problem, and if the floor of the mouth is also resected, the hyoid bone can fall back on the tra22

chea and interfere with respiration. Since anterior mandibular resection adversely affects swallowing, speech, mastication, ceordinated mandibular movements and aesthetics, immediate reconstruction should be seriously considered. This can be accomplished with either bone grafts (iliac crest or rib), alloplastic materials or a combination of these. As mentioned previously, good immobilization is imperative for success. (Alloplastic implants are discussed later.) Another problem encountered in mandibular resections is adequate intraoral and extraoral tissue closure. Grafts and flaps are often necessary to obtain adequate tissue. The soft tissue deformities can be just as debilitating as the osseous deformities. If sound teeth remain, they can help stabilize the remaining mandibular fragments, increase masticatory efficiency and retain prostheses if necessary. When the patient is edentulous, it is much more difficult to obtain a satisfactory reconstruction. The prosthetic prognosis for a unilateral resection in which the anterior curve of the mandible is intact is fair to poor, depending on the number of remaining teeth, alignment of remaining arches, extent of soft tissue defect and patient attitude and motivation. If the anterior segment is absent, the prosthetic prognosis is extremely poor. The reconstructive surgical procedures, even when indicated, usually do not significantly improve the prosthetic potential in mandibular rehabilitation. 1~

Maxillary Defects Defects of the maxillary area can be caused by cancer of the hard palate, soft palate, gingiva, lips, nasopharynx, paranasal sinuses and direct extension of the tumor from other areas. Since it is extremely difficult to obtain a satisfactory surgical repair with either grafts or flaps to this area, prosthetic reconstruction is almost always preferred. The problems encountered are: (1) lack of function of grafted tissue because of inadequate innervation, (2) excess tissue bulk, (3) gravity which continuously displaces tissue downward, (4) extraoral aesthetic defects at flap sites, (5) multiple surgical procedures and (6) elimination of any type of prosthetic reconstruction later because of interference of grafted tissue. Thus, to minimize complications, the reconstruction of choice in these defects is a prosthetic maxillary obturator. When the resection results in a defect of part of the maxillary ridge or soft tissue without communication between the oral cavity and nasal cavity, the disability is minimal and the prosthetic prognosis is excellent. The prosthetic design can be modified to accommodate the altered anatomy and aid in recontouring the remaining soft tissue. If the surgical resection creates a communication between the oral cavity and the nasal cavity, sinuses or nasopharynx, the disability can be severe. Speech is greatly impaired and is often un23

intelligible if the defect is not prosthetically restored. Oral competency is compromised because nasal secretions drain into the oral cavity, often creating a fluid problem along with an objectionable taste and odor. The patient is also unable to drink liquids without their escaping through the nose. This m a y cause nutritional problems as well as social embarrassment. Eating can become such a problem that a nasogastric tube is necessary to maintain adequate nutrition, and this again can cause the patient emotional problems and embarrassment. In addition, food will often get trapped in the nasal areas and become difficult to dislodge. There is also the constant risk of infection due to debris in the nasal cavities. There are certain surgical aspects in maxillary resections that m u s t be considered. First, it must be determined which tissues have to be sacrificed. The prosthetic prognosis can be greatly improved if a functional band of the soft palate with adequate musculature and nerve supply can be maintained. However, if a thin, nonfunctional, soft tissue band remains, it often interferes with the satisfactory construction of the obturator and should be removed surgically. 11 How the surgical pack is placed and how long it is to remain in place are prosthetic as well as surgical considerations. Patient comfort is improved with prosthetic replacem e n t of the palate. If natural teeth are present before surgery, the positioning of the line of surgical resection through the tooth socket (discussed in the section Mandibular Resection) applies equally well here (see Fig 9). Natural teeth are extremely valuable from a prosthetic point of view and should be maintained if at all possible. Even two or three moderately sound teeth can noticeably increase stability and retention of the planned prosthesis. For these reasons, the edentulous patient has a much more difficult time adjusting to his defect and prosthesis than does the dentulous patient. When the defect involves only a small area of the hard palate, the defect is minimal and the prosthetic prognosis is excellent. As the size of the defect increases, the prosthetic potential decreases. When the soft palate is involved, additional problems, such as the varied motion during speech, swallowing and mastication, are encountered. If the soft palate defect is large, it is often functionally better to extend the prosthesis through the defect on a line level with the crest of the vault of the hard palate rather than to follow the contours of the soft palate, in which instance gagging and swallowing difficulties can result. A total maxillary resection presents a challenging and difficult prosthetic rehabilitative problem because of the almost total lack of stability and of areas of retention. Fortunately, the soft palate often remains intact and can be used along with the anterior nasal spine area or floor of the nose for support. There are basically three types ofobturators: (1) immediate or 24

surgical (placed at surgery), (2) interim (placed 1 - 3 weeks after surgery) and (3) definitive (placed 6 - 1 2 months after surgery). Patient comfort is enhanced greatly with the placement of immediate obturators. The obturator helps protect the wound from irritation and debris and also acts as a stent against which postsurgical tissue can heal and contour. The obturator can also act as a well-adapted pressure stent for a skin graft that lines the defect. The nasogastric tube can be eliminated or removed earlier, since the patient can eat without fear of damaging the surgical site or getting fluid and food into the nasal areas. The patient's morale is usually better because he is able to care for himself, which also reduces the need for nursing care. Further, the pack's odor is less offensive because it is partially protected from contamination. There are prerequisites if an immediate obturator is to be utilized. At least a few natural teeth are required to offer the neces-" sary retention for the immediate placement of a prosthesis unless it is to be wired into place. If the patient is edentulous, it is usually better to place an interim appliance 1 - 3 weeks after surgery. Presurgical impressions of the maxillary and mandibular arches must be made for both dentulous and edentulous patients. The surgical impressions are most easily made by using irreversible hydrocolloid for the impression material. The impressions

Fig 12.-Presurgical cast of patient with squamous cell carcinoma of lingual gum area. Proposed surgical defect is outlined by surgeon; lines of resection go through depth of tooth socket on either side of defect after tooth was extracted. Also, right second and third molars are marked for extraction at the time of surgery because of advanced periodontal disease. Patient's teeth were scaled presurgically for removal of gross calculus and other debris to reduce chances of infection and enhance healing. _ [

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Fig 13.--Patient shown in Figure 12 with immediate obturator in place six days postoperatively. She was able to eat and maintain adequate nutrition starting from third day postoperatively. A transitional obturator was made at four weeks postoperatively because of tissue changes and to facilitate aesthetics.

should then be poured in dental stone and trimmed. At this time, the surgeon and the prosthodontist should meet, and the anticipated surgical defect must be outlined on the master cast by the surgeon (Fig 12). The cast is reshaped in the proposed surgical area to recontour to normal palatal form, and an immediate obturator is constructed with wrought wire and heat-cured acrylic resin or room-temperature vulcanizing acrylic resin. The obturator is then adjusted on a duplicate cast to as close a fit as possible and is placed in water to avoid warping until it is needed at surgery. The obturator must be adaptable at surgery. Most of these appliances require a minimum of adjustment in the operating room, b u t certain instruments, such as a grinding tool* for the adjustm e n t of the acrylic resin, contouring pliers to adjust clasps, coldcuring acrylic resin to extend areas that are inadequate and soft liner or tissue conditioning material to help retain and fill void areas should be available. The surgical pack should not extrude from the defect and interfere with the final placement of the obturator. Close follow-up by the surgeon and prosthodontist is necessary in all cases (Fig 13). An immediate obturator m a y not be desirable in some patients for these reasons: (1) a lack of teeth, which presents retention problems, (2) hemorrhage, for which the defect must be over*Moto-Tool Kit, Dremel Manufacturing Co., Racine, Wis. 26

packed and thus the obturator cannot be correctly placed and (3) preference for an interim obturator by the physician. The use of an interim obturator requires presurgical casts, thus avoiding patient discomfort in the tender postsurgical areas. The obturator can also be designed more accurately since the exact Fig 1 4 . - A , intraoral view of maxillary arch. Patient had surgery 3 years before for transitional cell carcinoma of antrum. There is excellent healing and minimal tissue distortion because immediate and transitional obturators were placed. Remaining teeth aid greatly in prosthetic repair of area. B, intraoral view of patient in A with definitive obturator in place. Chrome-cobalt framework is used for rigidity and retention. Scar band in left cheek area, in defect, is also used for stabilization.

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27

surgical margins are known. The obturator should be placed at the time of the first pack change (about 5 - 6 days postsurgery at M. D. Anderson Hospital) to reduce rapid tissue contracture during this stage of healing that would interfere in forming favorable postsurgical tissue contours. The patient is instructed on the insertion and removal of the interim obturator to allow for periodic irrigations of the surgical site. The appliance needs frequent adjustment, and the patient m u s t be followed up closely to check for rapid tissue change during the healing phase. His attitude frequently improves because of increased intelligibility of speech and better function. The interim obturator can be used in dentulous or edentulous patients. Anterior teeth can sometimes be added to the anterior section for aesthetic reasons, b u t it is better if occlusion is not accomplished at this time because of increased stress on the healing tissue. Definitive obturators are usually constructed 6 - 1 2 months after surgery. Most of the healing, fibrosis and scar formation have taken place by this time. The teeth, if present, and scar bands between the skin grafts and the mucosa are utilized to aid in retention and stability. If the remaining teeth are sound, chrome-cobalt or gold-cast partial denture frameworks with acrylic teeth and tissue areas are used to reconstruct the defects. The soft tissue contours are recorded with accurate impression materials, such as modeling plastic, wax* and rubber base. Functional impressions with the patient talking, drinking warm water, swallowing and moving the head in various positions are necessary to record the movements of the altered intraoral anatomy. Artificial teeth are set on definitive obturators to improve lip contour and dental aesthetics and to restore as much function as possible (Fig 14).

Combined Maxillary and Mandibular Intraoral Defects When maxillary and mandibular areas are involved with cancer, all the previously mentioned complications exist and are magnified. The resulting prosthetic rehabilitative prognosis decreases and it is often impossible to achieve an acceptable reconstruction for the patient. EXTRAORAL DEFECTS

Extraoral facial defects are commonly caused by cancer of the orbital area, maxillary sinuses, skin, ears, nose or other related structures. To obtain a reconstructive result that is acceptable to the patient with this type of defect can be challenging and difficult. In this section, we discuss some general considerations in *Korecta-Wax No. 4-Kerr, Romulus, M148174.

28

restoration of extraoral defects of the three main lesion sites (orbital, nasal and auricular) and their specific problems. Often, prosthetic reconstruction of extraoral defects is superior both aesthetically and functionally to results obtained surgically, especially in ear and nasal replacements. Patient acceptance of a prosthesis and the responsibility of its care are important factors to stress. Some patients prefer to wear a bandage rather than a prosthesis over a defect and their wishes should be respected. Patient factors discussed previously, such as hospitalization costs, operating room costs, time lost from work and medically related problems, apply equally well here and must be evaluated. Tissue margins of the defect cannot support a prosthesis immediately after surgery. However, immediate prostheses may be used if extended beyond the surgical margins but not into the surgical defect. Each patient must be evaluated individually to determine the appropriate time for reconstruction to begin. Advance planning and good presurgical records, such as roentgenograms, photographs, intraoral impressions and facial moulages are helpful in many cases of head and neck surgery and in later reconstructions. Moulages are usually made of reversible or irreversible hydrocolloids, silicone-base materials, rubber basetype materials and plaster of Paris. Each has its advantages and disadvantages. A realistic evaluation of how the defect will be restored should be made on an individual basis. Ifprosthetics is to be used alone because of the extent of the deformity and the lack of underlying support for future surgical reconstruction, the surgery should be planned to allow the most favorable postsurgical tissue contour for the prosthesis. For example, small tissue tags are often unnecessarily left and can create retention problems and aesthetically affect the quality of the prosthesis. The flexibility of these tags causes a constant dislodging force on the prosthesis. Joint advance planning by the surgeon and prosthodontist can often avoid these problems. Currently, the most frequently used materials for extraoral appliances are polyvinylchloride, silicone rubber materials, urethane and occasionally methylmethacrylate. There is no ideal material for all patients, and each patient must be evaluated individually to determine which material is most suitable. Lack of color stability and soft texture durability of the prosthesis are two of the main drawbacks with the present materials. Environmental factors, such as ultraviolet light, petrochemical fumes, cooking odors, heat and cold and many others, accelerate the deterioration of the prosthesis. Patient factors, such as smoking, tobacco chewing, skin secretions and personal hygiene, are added variables that affect the longevity of the restoration. Improper daily cleaning of the appliance also decreases longevity of the prosthesis because of abrasion and the action of the cleaning agents. If the color can be placed internally, rather than on the surface, its 29

stability will be lengthened. Many of the materials can be improved by embedding white nylon stocking material in these areas for added strength. Many times, better aesthetics can be obtained with a prosthesis than with a surgical repair. Contour, as well as color, is important. The overall contour on most prostheses is excellent, b u t the problem is in the placement of margins into hidden areas. The folds of the skin and natural surface contours can be used effectively for this. For example, ending a nasal prosthesis in the ala area of the nose can make the margins practically invisible. Hair styles can be changed to cover margins in auricular or extensive orbital prostheses and glasses can hide margins and help retain nasal and orbital prostheses. Cosmetics can also be used to advantage in many instances. However, the most difficult area to disguise is a smooth surface, such as a cheek. If the margins can be thin, they blend better with the tissue contours and are less noticeable, but they are weaker. Coloration of the prosthesis is also of prime importance. If the skin is mottled, heavily freckled, or has an uneven texture, it is much easier to match. Polyvinylchloride is a good material for this type of skin, because varied intrinsic coloring can be "painted in" easily. A clear "peaches and cream" complexion is the most difficult to match. Urethane is a good material for use in this instance because of its translucency and evenness in color. Skin coloration changes normally for a variety of reasons, such as season and temperature (sunburns, tans and other factors), emotional state (blushing and anger) and varying light sources (sunlight, incandescent and fluorescent). The prosthesis, of course, does not change and, therefore, it creates variations in facial coloring. Cosmetics can be used to blend variations in color. Retention is another factor that m u s t be considered. If the tissue margins are not fragile, the prosthesis can be extended into undercut areas. Natural tissue contours can be utilized to gain additional stability. The two methods of retaining extraoral prostheses are usually by a special adhesive* and a bifaced tape.t Glasses, even if they are not used to correct vision, can aid retention and contribute to aesthetics. When a later surgical reconstruction is not contemplated in the nasal area, unnecessary tissue tags should not remain, especially in the ala area. It is much better from a prosthetic rehabilitation standpoint to remove them. The prosthetic margins can be disguised in the ala area by following the contours of the nasolabial fold. Glasses can greatly reduce the evidence of the superior margins and aid in stability (Fig 15). In prosthetic replacement of an ear, the leaving of tissue tags or *Medico Adhesive, Slomons Laboratories, Inc., Long Island City, New York, NY t3M Brand Surgical Tape, double-coated polyethylene catalog no. 151 ~1/2in. • 72 yards). Corona Graphics, Houston, TX 77018.

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Fig 1 5 . - A , when seen at M. D. Anderson Hospital and Tumor Institute, patient's nose had been removed after repeated surgery for removal of recurrent basal cell carcinoma. It would have been desirable if tissue tags (arrows) in the ala area had been removed for prosthetic reconstruction. B, nasal prosthesis constructed of polyvinylchloride and retained with adhesive. Glasses can be used to help retain prosthesis and conceal superior margins.

partial ears creates a problem. If the tragus and crus can be retained, the anterior margin can be hidden behind these structures. The external auditory canal can be used to good advantage to gain additional retention. If, for example, half an ear remains, it is difficult to obtain a satsifactory replacement. If radiotherapy Fig 1 6 . - A , patient with missing left ear. Note tragus remains and that there are no unnecessary tissue tags. B, polyvinylchloride prosthetic ear replacement. Margins can be blended into hidden areas with tragus intact.

A

B

31

Fig 1 7 . - A , 16-year-old patient with transitional cell carcinoma with extensive antrum involvement. This patient had an even peaches and cream complexion that makes color matching of the extaoral prosthesis difficult 9 B, patient with urethane orbital prosthesis in place; prosthesis is retained by adhesive applied to the margins. C, glasses can be used to enhance overall aesthetic result of prosthetic reconstruction in same patient9

is planned after surgery, it is often better to remove the ear to reduce the patient's discomfort resulting from possible cartilage necrosis. Because of wide variations in the a n a t o m y of the ear, it is advantageous to do a presurgical impression if the ear is not too deformed from the cancer. The opposite ear m a y be used as a mirror image model for later reconstruction. Since most people notice only facial symmetry, they are less aware of each ear, be it real or prosthetic, and hair can be restyled to partially cover the area and m a k e it less noticeable (Fig 16). When an orbital enucleation has been performed, a successful prosthetic replacement can usually be made. However, exentera32

tion of the orbit can create a difficult reconstructive situation. The margins in this type of restoration are difficult to hide since they often end on visible smooth surfaces, such as the cheek. Because of the wide variation in tissue movements t h a t tend to dislodge the prosthesis, it is difficult to obtain good marginal tissue seals. Color matching of the eye and surrounding tissues can be a problem. The artificial eye in the orbital prosthesis does not track, so the patient must be t a u g h t to move his head and look directly at the object rather than just to shift his eyes. Positioning of the eye is critical, and even a little variation in any direction can detract from the overall effect. Glasses, especially tinted ones, can be an asset to aesthetics and retention (Fig 17). Some patients prefer to wear an eye patch r a t h e r t h a n a prosthesis, and their desires should be respected. When a defect involves more t h a n one of the previously discussed extraoral areas or extends into other areas, the problems are magnified. The lip is extremely movable tissue, and if the defect includes this or extends near it, difficulties in retention, stability and marginal seal are increased.

INTRAORAL-EXTRAORAL DEFECTS Unfortunately, lesions are not always confined to the intraoral or the extraoral area. As the areas involved become more extensive, the reconstrucitve prognosis decreases and the problems of retention, stability, aesthetics and function are magnified. The only general rule here is t h a t the intraoral reconstruction m u s t be completed before initiating extraoral repair because the intraoral prostheses determine the extraoral tissue contours.

ALLOPLASTIC IMPLANTS Since surgery for cancer of the head and neck often results in extensive deformities, reconstruction of these defects with bone and alloplastic materials has been used increasingly.Our discussion here will pertain only to mandibular implants, although other areas can be reconstructed. Many types of materials have been suggested for implants, but they are usually classified into three main types: (1) medical-gradepolymers (dacron, acrylics, silicone, Teflon),* (2) ceramics and (3) metals (gold, silver, titanium, tantalum, 18.8 stainless steel plates (18% chromium,0.8% nickel) and chromium-cobaltalloys).'2 Various metals and acrylics presently seem to be best adapted to mandibular replacement. Gold and silver are not widely used, mainly because of prohibitive cost. Tantalum is used generally as supporting trays for stabilizing bone grafts (rib or iliac crest) and as inferior mandibular *DuPont,LosAngeles,CA90022. 33

trays to hold bone chips. Stainless steel plates (18.8) can be used alone or in combination with acrylic resin for reconstruction. Proplast,* a combination of Teflon and pyrolytic graphite, is used to coat the metal or acrylic resin to increase retention by tissue ingrowth. Chrome-cobalt and titanium are used in varied designs to replace the mandible or in trays to support bone grafts. There seems to be general agreement that if the correct shape of autogenous bone is available for grafting and if it can be immobilized, this is preferable for reconstruction. Unfortunately, because of the irregularly curved surfaces of the mandible, this is frequently not the instance, and alloplastic materials should be considered. To perform any implant successfully, certain prerequisites must be met. There must be adequate soft tissue available for coverage both intraorally and extraorally. If the tissue is sutured under tension, it can undergo necrosis and expose the implant. When this happens intraorally and the exposed implant makes contact with saliva, the breakdown can be accelerated and lead to rapid failure. Adequate immobilization of the implanted materials is necessary to allow for healing and to avoid displacement. Kirschner wires can be used successfully for temporary replacement to maintain approximate positions of the mandibular fragments, but because they have a tendency to break, work loose and destroy bone at their attached sites in the mandibular stumps, they should not be used for permanent reconstruction (Fig 18). A favorable tissue bed with a good blood supply can enhance the possibility of implant success. If tissue has been irradiated Fig 18.-Kirschner wire placed three months earlier as definitive reconstruction. Note wire is broken and proximal ends have destroyed bone in mandible. It is difficult to adequately stabilize this type of reconstruction, and it should only be used for short-term repair. Patient's defect is presently being maintained with extraoral pin fixation and intermaxillary wiring. This was later reconstructed using a chrome-cobalt mesh tray with a bone graft.

*Smith Kline & French, Surgical Specialties, Philadelphia, PA 19101. 34

with resultant reduction of blood supply and increased fibrosis, the prognosis is poor. When the area is to be irradiated postsurgically, a large amount of metal in the implant can create problems for the radiotherapist because it shields tissue from necessary radiation and has a tendency to cause backscatter and secondary irradiation, which can create ~'hot spots" and tissue breakdown. Postoperative irradiation ( 4 - 6 weeks after surgery) will almost always guarantee the failure of a bone graft; therefore, acrylic resin can be successfully used since it does not ionize when exposed to radiation and has the same density as the surrounding tissue, preventing alteration of dosimetry curves. Also, there must, of course, be no pathologic abnormalities in the tissue bed to receive an implant. As always, thorough advance planning, with good presurgical records, is necessary. From the clinical examination and highquality diagnostic roentgenograms, the extent of the proposed resection can be determined as accurately as possible. Intraoral and extraoral (moulage) impressions aid in determining the contour and extent of the implant. A soft-lead wire is bent to conform to the inferior edge of the mandible to record its contours. Photographs and roentgenograms, such as panographic and cephalometric films, aid in determining the relationship of the implant to the residual tissue and the dimensions of the osseous structures. Allowing adequate time for obtaining presurgical records, for planning and for fabrication of the implant is an aspect that is often overlooked by the surgeon: If acrylic resin is to be used, a model must be made in wax and then flasked and cured for 20 hours to eliminate any free monomer in the acrylic resin that can cause irritation to the tissue bed. This acrylic resin must then be gas sterilized. The time sequences emphasize the importance of having both the physician and prosthodontist see the patient early in the planning stage. Tantalum trays can be made in approximately one day, b u t they must be pressed for 10 hours to reduce the rebound effect of the metal. Vitallium and chrome-cobalt must be made in wax and then cast and finished, which can require 4 - 5 days or more. The 18.8 stainless steel plate implants can be fabricated rapidly if the metal is available and they are easily sterilized. All the metal implants can be steam sterilized while surgery is progressing. These implants can be attached to the remaining bone segments with wire, bone screws, bolts or cold-curing acrylic resin. All these implants must be adjustable at surgery, since it is often impossible to determine preoperatively the exact margins of resection and the exact size needed for the replacement by the prosthesis. Frequently, a number of different designs are taken to the operating room to allow for this variability. The necessary instruments to place and adjust the prosthesis must be assembled and available at the time of surgery. After the 35

r e s e c t i o n is completed, t h e p r o s t h o d o n t i s t should place t h e i m p l a n t s , since h e is m o s t f a m i l i a r w i t h t h e i r design. I m p l a n t s c a n be v a l u a b l e a d j u n c t s to h e a d a n d n e c k s u r g e r y a n d s h o u l d be considered for p a t i e n t s w h e n d y s f u n c t i o n a n d a e s t h e t i c d e f o r m i t y will r e s u l t f r o m t h e n e c e s s a r y s u r g i c a l procedure.

SUMMARY D e n t a l m a n a g e m e n t of t h e p a t i e n t w i t h cancer, e s p e c i a l l y w h e n t h e d i s e a s e process i n v o l v e s t h e h e a d a n d n e c k region, s h o u l d be a n i n t e g r a l p a r t of t h e p a t i e n t ' s o v e r a l l t r e a t m e n t plan. By u t i l i z i n g t h e t e a m a p p r o a c h a n d d e t a i l e d a d v a n c e p l a n n i n g , s t r e s s i n g b o t h i m m e d i a t e t r e a t m e n t to control t h e p a t i e n t ' s dise a s e a n d short- a n d l o n g - t e r m r e h a b i l i t a t i o n , t h e b e s t possible t r e a t m e n t for e a c h p a t i e n t c a n b e f o r m u l a t e d w i t h a m i n i m u m of p o s t t r e a t m e n t complications. I f a n i n s t i t u t i o n is to m a k e t h e c o m m i t m e n t to t r e a t p a t i e n t s w i t h cancer, a c o m p r e h e n s i v e d e n t a l s u p p o r t p r o g r a m w i t h a m a x i l l o f a c i a l p r o s t h o d o n t i s t is a necessity. As t h e benefits of a d e n t a l d e p a r t m e n t a r e recognized, t h e u t i l i z a t i o n of t h i s s e r v i c e i n c r e a s e s a n d t h e o v e r a l l t r e a t m e n t a n d r e h a b i l i t a t i o n of t h e pat i e n t w i t h c a n c e r is i m p r o v e d . REFERENCES 1. Drane, J. B.: Development plan for the department of dental oncology, M. D Anderson Hospital and Tumor Institute, February, 1976. 2. Moore, C.: Cancer control. Presidential address given before the Annual Meeting of The Society of Head and Neck Surgeons (April 1976). 3. Daly, T. E., and Drane, J. B.: Management of dental problems in irradiated patients. Annual meeting of the Radiological Society of North America, Chicago, November 26- 29, 1972. 4. Bodey, G. P., Buckley, M., Sathe, Y. S., and Freireich, E. J.: Quantitative relationships between circulating leukocytes and infection in patients with acute leukemia, Ann. Intern. Med., 64:328, 1966. 5. Lindquist, S., and Hickey, A. J.: Unpublished data. 6. Bulbudian, A. H.: Maxillofacial prosthetic: Evolution and practical application in patient rehabilitation, J. Prosthet. Dent., 15:554, 1965. 7. Nakamoto, R. Y.: Unpublished data. 8. Shannon, I.: Personal communication. 9. Cantor, R., Curtis, T. A., Shipp, T., Beumer, J., and Vogel, B.: Maxillary speech prosthesis for mandibular surgical defect, J. Prosthet. Dent., 22:253, 1969. 10. Cantor, R., and Curtis, T. A.: Prosthetic management ofedentulous mandibulectomy patients: Part I. Anatomic, physiologic and psychologic considerations, J. Prosthet. Dent., 25:446, 1971. 11. Aramany, M. A., and Matalon, V.: Prosthetic management of postsurgical soft palate defects, J. Prosthet. Dent. 24:304, 1970. 12. Parel, S. M., Drane, J. B., and Williams, E. O.: Mandibular replacements: Review of the literature, J.A.D.A. 94:120, 1977.

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ADDITIONAL BIBLIOGRAPHIC SELECTIONS Clark, R. L., and Howe, C. D.: Cancer Patient Care at M. D. Anderson Hospital and Tumor Institute (Chicago: Year Book Medical Publishers, Inc., 1976). Carl, W.: Preoperative and postoperative obturators, J. Prosthet. Dent. 36:298, 1976. Carl, W., and Schaaf, N. G.: Dental care for the cancer patient, J. Surg. Oncol. 6:293, 1974. Rahn, A. O., and Boucher, L. J.: MaxillofacialProsthetics, Principles and Concepts (Philadelphia: W. B. Saunders Co., 1970). MacComb, W. S., and Fletcher, G. H.: Cancer of the Head and Neck (Baltimore: Williams & Wilkins Co., 1967). Chalian, V. A., Drane, J. B., and Standish, S. M.: Maxillofacial Prosthetics Multidisciplinary Practice (Baltimore: Williams & Wilkins Co., 1971). Fletcher, G. H.: Textbook of Radiology (Philadelphia: Lea & Febiger, 1973). Maldonado, O., Dreizen, S., Matalon, V., et al.: Dental oncology. Cancer B,'" 29:57, May-June, 1977.

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