The maxillary resection and its prosthetic replacement

Maxillo f acial prosthesis

The maxillary

resection

and its prosthetic

George Albert Zarb, B.D.S., MSc., The Ohio State University, College

replacement

D.D.S.*, MSc. (Ohio) of Dentistry, Columbus,

Ohio

lhe objective of this article is to describe the anatomy of a resected maxilla, and to propose a method for its prosthetic replacement. Radical surgical treatment of tumors of the maxilla is undertaken in an effort to obtain a better survival rate. I-* Following such tumor surgery,5. ’ the prosthodontist is called upon to play a major ro!e in patient rehabilitation. The success of the prosthesis will depend largely on its relation to the various anatomic structures it replaces as well as supports. Familiarity with these structures is obviously essential. This study aims at: describing the surgical anatomy of a maxillary resection and identifying the osseous structures involved; correlating the residual anatomic structures with the replacement prosthesis; and discussing the method of prosthetic rehabilitation of a resected maxilla. SURGICAL OSSEOUS

ANATOMY STRUCTURES

OF A MAXILLARY INVOLVED

RESECTION

AND

THE

Resection12 3, 4 was carried out on the head of a cadaver. The first step consisted of the exposure of the facial surface of the maxilla. This was accomplished by a skin incision, as outlined in Fig. 1. The upper lip was split in the midline to the columella. Next, an incision was made across the base of the nose into the nasolabial crease, and was extended around the ala, and then superiorly along the maxillary crest to the infraorbital ridge. The incision then curved laterally on the lower eyelid, and followed a line just below the border of the lid, out to the zygomatic bone. The gingivolabial fold was next incised at the superior aspect of the lip-splitting incision. The incision was extended posteriorly to the posterior border of the maxilla. The outlined skin flap was reflected from the tarsal plate superiorly, and *Presently Surgeon, Toronto

Assistant General

Professor, Hospital.

This article and the Journal Editors.

is being of the

published Canadian

268

Faculty

of Dentistry,

University

of Toronto,

and

Dental

simultaneously in the JOURNAL OF PROSTHETIC DENTISTRY Dental Association by special arrangement between the

Volume Number

18 3

Fig. 1 The skin incision

Maxillary

for a maxillary

resection

resection outlined

and prosthetic

replacement

269

on a cadaver head.

the infraorbital margin was exposed. The nasal cavity was entered along the margins of the maxillary crest. The flap was next reflected from the anterior surface of the maxilla (Fig. 2)) to which the periosteum was left attached. Although an extensive incision, surgeons .find it necessary in order to expose the maxilla maximally. The second step consisted of a mobilization of the maxilla by freeing it from its bony and soft tissue attachments. The zygomatic arch was exposed and the orbital periosteum elevated. A perforation was made through the lateral wall of the orbit just beneath the attachment of the zygomatic arch. This attachment was transected with a saw (Fig. 3, A) . In vivo, if the tumor does not involve the roof of the maxillary antrum, the orbital floor and margin are preserved. The zygoma is cut horizontally, about one-half inch below the orbital margin; and vertically, just lateral to the maxilla. The nasal-ethmoid-orbital attachment was next severed’with a chisel that was directed posteriorly to cut the maxilla from the ethmoid (Fig. 3, B). The landmark for this cut was the superior rim of the lachrymal fossa. The intranasal line of section was just above the middle turbinate and anterior ethmoid cells, and just below the cribriform plate. Before the hard palate was sectioned, the mucous membrane was incised; the incision commenced at the posterior aspect of the gingivolabial incision, and extended through the soft palate to the midline, at the junction of the soft and hard palates. (Whenever circumstances permit, a rim of soft palate is preserved in vivo. This will facilitate the eventual construction of a watertight prosthesis.) The bony palate was split in the midline (Fig. 4, A, B) and the posterior inferior attachment of the pterygoid plates was severed (Fi,.(+ 5). Next, the muscle fibers of the masseter and internal pterygoid muscles, and the reflection of the orbital periosteum from the superior maxillary surface were severed. The maxilla was grasped with forceps and rocked out of position.

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J. Pros. Dent. September, 1967

Zarb

Fig. 2 Reflection of the skin flap from the anterior bone and periosteum.

surface of the maxilla

showing

the underlying

A

B

Fig. 3 Landmarks for a maxillary resection on a skull (A) and a cadaver (B). A, Vertical cut through the zygomatic arch. B, Horizontal cut at the superior rim of the lachrymal fossa. C, Vertical cut in the maxillary midline.

In vivo, the whole field of operation is next carefully examined. Various possibilities of tumor extension exist: the orbit; the ethmoidal, sphenoidal, and frontal sinuses; the skin; the pterygoid muscles; and the temporomandibular joint region.’ Since the interior of the skin flap and the muscle bed of the maxilla are denuded, a split thickness skin graft is sutured into place, covering all denuded areas (Fig. 7). Petroleum jelly gauze is packed into the cavity, and the initial skin lesion is approximated. The use of skin grafts is considered one of the most important recent advances in radical surgery of the maxilla.’ These grafts thrive equally well on the cheek flap, the muscle bed, the bare bone, the dura, or the cerebral cortex. Their use simplifies postoperative packing of the cavity by making the area less tender. Also,

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Maxillary

resection

and prosthetic

replacement

A

Fig. 4 Mobilization of the maxilla. (;I;] and bony skull (B).

271

B

The palate is incised and split in the mid-line

Fig. 5 Mobilization of the maxilla. The pasteroinferior pterygoid plates. Fig. 6 A maxilla approximating the excised bone.

cadaver head

line of section is in the region

the cosmetic result is improved. If a skin graft over the surgical area may be conspicuous.4

is omitted,

CORRELATION OF THE RESIDUAL ANATOMIC WITH THE REPLACEMENT PROSTHESIS

STRUCTURES

shriveling

of the

or scarring

A maxillary resection results in a continuity of at least the nasal and maxillary sinus cavities on the surgical side. This anatomic defect is bounded as follows (Figs. 8 and 9) : medially, by the nasal septum; posteriorly, by a vertical plane through the anterior border of the residual soft palate; laterally and anteriorly, by the inside of the cheek with its skin graft lining; superiorly, by the floor of the orbit and the

272

Zarb

Fig. 8

Fig. 7 An acrylic resin prosthesis in place. A, The reflected skin flap is lined with a simulated skin graft. B and C, The soft palate. Fig. 8 The boundaries of the anatomic defect following a maxillary resection. A, The nasal septum. R, The orbital floor. C, The inside of the cheek muscle bed. D, The residual hard palate. E, The residual soft palate.

cribriform plate (if the ethmoid labyrinth is exenterated) ; inferiorly (Figs. 10 and 13)) by a horizontal plane extending from the residual hard and soft palates to the fibrous contraction band which forms in the region of the top of the sulcus on the resected side.x The inferior boundary separates the oral cavity from the surgical cavity, as well as from the obturator and oral parts of the replacement prosthesis. The obturator portion is made up of a suprapalatal extension and an anterolateral or maxillary extension (Fig. 11). That part of the prosthesis which supports the cheek on the resected side is called the vestibular portion (Figs. 11 and 12). It consists of a shield-like arch which occupies what used to be the labial and buccal vestibule on the resected side. The obturator and oral part of the prosthesis are separated by a groove which is caused by the fibrous contraction band and the anterior border of the soft palate (Fig. 11) . Detachment of the pterygoid hamulus almost inevitably occurs in a maxillary resection. This can affect three muscles which are intimately associated with the hamulus and its attached raphe: the tensor veli palatini, the buccinator, and the superior pharyngeal constrictor muscles. The tensor veli palatini passes downwards from the base of the skull, and continues into a strong tendon just above the level of the pterygoid hamulus. The tendon then winds around the hamulus and bends sharply from a vertical into a horizontal plane. ’ The pterygomandibular raphe is a tendinous band stretching from the tip of the pterygoid hamulus to the retromolar

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resection

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reflacement

273

Fig. 9 A frontal

Fig.

section

in

the

mouth

and

nose

region

of a resected

maxilla.

10

The inferior boundary hard palate. B, The buccal sulcus.

of surgical residual soft

area palate.

as seen in an edentuious C, The fibrous contraction

patient. band

A, The residual at the top of the

274

Fig.

Zarb

J. Pros. Dent. September, 1967

11

Left, A permanent prosthesis with a Silastic obturator and a cast framework. A, The suprapalatal extension. B, The maxillary extension. C, The vestibular arch. II, The groove in the prosthesis caused by the fibrous contraction band. Right, An immediate temporary obturator with wrought wire clasps, and a compound obturator extension, E.

Fig. A

12

temporary

triangle

obturator

in

the

mouth

showing

the

vestibular

arch

part

of

the

prosthesis.

of the mandible. Parts of the superior pharyngeal constrictor muscle the tip of the hamulus and from the raphe. Anteriorly, fibers of the muscle arise from the raphe. All three muscles tend to cause a lingual the inferior posterolateral corner of the surgical area (Fig. 10). Marked of the cheek may be caused by the loss of its bony support (Fig. 14).

(pad)

arise from buccinator collapse of contraction

THE METHOD

OF PROSTHETIC

REHABILITATION

OF A RESECTED

MAXILLA

The immediate postoperative days are difficult ones for the patient who has undergone a maxillary resection. The patient is acutely aware of his unintelligible speech and altered eating habits. Moreover, contraction of the operative site occurs dramatically, with resultant collapse of the soft tissues over the resected jaw. The

Maxillary

Fig.

13

resection

and Brosthetic

replacement

Fig.

275

14

Fig. 13 The anterior aspect of the inferior boundary of the surgical region in a dentulous patient, A, The residual hard palate. B, The fibrous contraction band at the top of the labial sulcus. Fig. 14 Marked contraction of the cheek resulting from lack of support of the soft tissues on the resected side.

prosthodontist’s responsibility in caring for such patients is divided into three stages: the immediate temporary obturator stage; the permanent obturator stage; and the maintenance phase of the patient’s prosthetic treatment. The Immediate Temporary Obturator Stage. The advantage of an immediate temporary obturator is the preservation of normal speech and eating habits. Collapse of the soft tissues on the affected side may also be prevented. Facial symmetry will then be preserved, and the construction and retention of the permanent prosthesis will be facilitated. Above all, the mental well-being of the patient is boosted considerably. Retention of the immediate temporary obturator in the edentulous patient is not always possible. Miglani and Dranel” consider the presence of teeth on the nonsurgical side a prerequisite for an immediate obturator. They fabricate a temporary obturator in edentulous cases about ten days postoperatively. Lingermanll recommends wire attachment of the immediate obturator to the zygomatic arches on either side. James? uses a sponge prosthesis approximately ten days after the operation. The sponge is removed by the patient and cleaned after each meal. Both Steadmar? and Hammondl” use gutta-percha on the deficient side of the immediate obturator to maintain cheek contour and obtain retention (Fig. 11). The guttapercha becomes dirty, however, and has to be replaced. It also makes the obturator rather heavy. Robinson6 places an 18 gauge wire loop on the defective side of the obturator. He obtains retention by suturing the loop to facial musculature and skin. If the orbital contents are exenterated, he extends the suture material up through the orbital opening and seals it to the forehead with adhesive tape. An immediate temporary obturator is almost always indicated, as well as feas-

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ible, in a maxillary resection. When a good rapport exists between the prosthodontist and his surgical colleague, the latter may ask what steps he should take to facilitate the treatment and prosthetic work. Diagnostic casts enable the surgeon to adequately outline the proposed area of resection (Fig. 15) . An acrylic resin denture base (having the same periphery as an ordinary denture) is constructed, or else the patient’s own denture may be used. The area to be resected is outlined on the denture base and filled in with autopolymerizing resin. Immediately after the surgeon has completed the resection and the skin graft is in place, the obturator, with a resilient denture material added to it, is inserted into the anesthetized patient’s mouth. When the soft liner material has set, the prosthesis is removed. Areas of hard acrylic resin showing through the liner are relieved and excess material is trimmed. Temporary obturation with a resilient material which can be easily added to is important because of the minimal pressure exerted by the obturator. The resilient liner not only protects the healing tissues, but may help retain the prosthesis by engaging and springing over undercuts which are present. Wrought clasps should be included in the fabrication of an immediate temporary obturator for dentulous patients (Fig. 11) . Instructions are given that the obturator must not be removed from the patient’s mouth except in an emergency. The prosthesis may be removed 24 to 48 hours after the operation, washed, and if necessary adjusted. The patient is shown how to remove and insert the prosthesis, since it must be cleaned thoroughly after meals. The patient is also told that he must not remove the obturator for any long period of time. Wound contraction during the early healing stage is so rapid that reinsertion may be rendered difficult or impossible.

Fig.

15

Fig. 15 A preoperative diagnostic cast with the surgeon’s outline of the extent of the proposed resection. Fig. 16 A stock impression tray that was altered with compound for making a preliminary immade perforated resin tray. pression, and a custom

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resection and prosthetic

replacement

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The prosthodontist should not be in too great a hurry to provide teeth for the obturator. The soreness following radiotherapy usually prevents wearing anything more elaborate than the simplest appliance. At this stage, the mucous membrane seems to be particularly fragile and subject to ulceration by dentures. Edentulous patients manage to use their lower dentures very efficiently against a simple obturator. The Permanent Obturator Stage. A permanent obturator may be made after the cavity is thoroughly healed. The time element varies with individual patients, but is approximately six to eight weeks postoperatively.‘, I3 The primary aim of the prosthodontist is not to completely replace the lost part of the jaw,14 but to preserve the functions of speech, deglutition, and possibly soft tissue support already accomplished by the immediate temporary obturator. The techniques used are routine clinical prosthetic ones. Meticulous attention must be paid to all the stages carried out in the fabrication of the permanent prosthesis. A perforated acrylic resin custom tray is made from the patient’s diagnostic cast, or from an Alginate (irreversible hydrocolloid) impression made in an altered stock tray (Fig. 16). The custom tray is placed in the patient’s mouth, and adjusted by relieving overextended borders, or by adding green stick compound to underextended borders. The surgical cavity is packed with gauze saturated with petroleum jelly except for undercut areas which are to be included in the final prosthesis for retentive purposes. Dental tape is tied to the gauze in order to prevent its dislodgment into the back of the throat (Fig. 17). Alg inate is the preferred impression material, since it is so “clean” and easy to handle. A cake decorating syringe can be used to inject Alginate into the cavity prior to carrying the Alginate-filled tray into the mouth. If the Alginate tears during withdrawal of the impression, the Alginate pieces can be reassembled with pins, and a stone cast poured. The impression

F::. 17

Fig. 17 The surgical cavity is packed with “taped” gauze saturated with petroleum jelly prior to making impression. Fig. 18 An Alginate impression made after the maxilla was resected. Note the suprapalatal extension..

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J. Pros. Dent. September, 1967

Zarb

(Fig. 18) is examined for pressure areas, which can be detected wherever the tray shows through the Alginate. If present, another impression should be made. The occlusal relations are registered on acrylic resin trial denture bases that have wax occlusion rims. The trial denture bases may be adequa.tely retained by using a soft liner material to engage the undercuts on the stone cast. If the patient is dentulous, the cast framework is used to retain the occlusion rim and trial denture base. The maximum number of teeth should be incorporated into the partial denture framework design in order to achieve maximal stability. The casts are mounted on an adjustable articulator by means of a face-bow. Waxing-up and processing of the denture is then carried out in the usual manner. The weight of large obturators can be reduced if they are made hoIlow.5, If; This can be done by constructing the prosthesis in two sections, and then joining these two parts with autopolymerizing acrylic resin. Coffin’” prefers a hollow obturator that is open at the top for efficient cleaning. Occasionally, the final prosthesis may be made to fit precisely as high up in the defect as possible anteriorly and laterally in order to support the side of the face (Fig. 19). However, this is rarely feasible. The medial wall of the prosthesis along the midline of the palate need only be as high as the hard palate is thick; anything higher will not abut onto anything, and consequently, would serve no useful purpose.

Fig. 19 A diagram

of the frontal section of an obturator

in position.

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The obturator is inserted on edge, and rotated into position in order to make full use of the undercut lateral wall. The patient must learn to insert and remove the prosthesis before being dismissed from the hospital. Those appliances inserted in a vertical direction will have poor retention. If this is necessary because of the presence of undercuts on the intact tissue side, a resilient material should be used to engage one or more of these undercut areas. Silastic 390” is admirably suited for this purpose,l’T I8 and affords maximal retention without irritation or trauma to the soft *Dow Corning,

Midland,

Mich.

Fig. 20 An intraoral view after the maxilla in a 22-year-old Fig. 21 The prosthesis in place.

man was resected.

Fig. 22 The three year postoperative cosmetic result. The patient obturator followed by a permanent prosthesis.

wore an immediate

temporary

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J. Pros. Dent. September, 1967

Zarb

tissue. Recently, several dentures having fungal growth on Silastic liners have been could very well render doubtful the use of Silastic in reported. Ig-*l Such growths patients whose oral flora harbor the yeast-like molds responsible for the changes in the surface texture of the material. Figs. 20 to 22 demonstrate the prosthetic rehabilitation of a dentulous twentytwo-year-old man who underwent a maxillary resection for a mucoepidexmal carcinoma of the palate. The excellent facial contour preserved by the wearing of immediate temporary and permanent prostheses is evident from the photograph made three years postoperatively. The Maintenance Phase of a Permanent Obturator. Periodic recall of patients wearing obturators is necessary in order to ensure the patients’ continued comfort and the optimal health of oral tissues. Moreover, the easy removal of the prosthesis allows for the prosthodontist’s unobtrusive watch of the surgical area, which is so easily accessible. Since the dimensions of the surgical cavity continue to change for a prolonged period of time, the posterior edge of the prosthesis may no longer provide a satisfactory seal. The patient will complain of unsatisfactory retention of the prosthesis and/or of the passage of fluids into the nasal cavity and through the nostrils. When fluids are swallowed, the tongue forces them against the palate and over the posterior part of the denture. The fluids then run forward and exit through the nose, especially when the head is tipped forward. A localized reline of the obturator will adequately recover the posterior seal. This part of the denture is ground slightly, green stick compound is applied, and functional muscle movements of the soft palate are carried out until the seal is complete. The contact area in the compound is scraped to a depth of 0.5 to 1.0 mm., and a zinc oxide and eugenol impression paste is added to the cut surface. Functional movements are carried out again, and a partial cast is poured up to this localized impression in the prosthesis. The compound and impression paste are removed, and autopolymerizing (cold-curing) acrylic resin is packed into the deficiency. The fresh resin is processed under air pressure in order to avoid porosity. Alternately, a functional impression material may be used. This material should flow and should not rebound.22 t&e-comfort* has this property, provided the impression is removed from the mouth within a few hours. If left in the mouth for a few days, the cast should be poured up immediately after the impression is removed, because of the rapid recovery of this material. Occasionally this procedure still fails to solve the patient’s complaint of nasal drip accompanying the swallowing of liquids. A hole can be drilled into the posteromedial side of the obturator to an area just above the cuspid or first bicuspid. If the obturator is a hollow one, a resin tube can be fitted accurately through the holes and retained with cold-curing resin. The fluids will pass into the tube upon entering the back of the nasal cavity, and return to the mouth at the labial opening. SUMMARY The structures

surgical anatomy of a maxillary involved have been identified,

*Coe Laboratories,

Chicago, 111.

resection has been described. The osseous and the residual anatomic structures cor-

Volume 18 Number 3

Maxillary

related with replacement prostheses. a resected maxilla has been discussed.

resecticn The

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and prosthetic rehabilitation

replacement of a patient

281

with

References 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22.

James, A. G., and Raines, D. R.: The Management of Cancer of the Maxillary Antrum, Surg. Gynec. & Obst. 101: 395, 1955. Mattick, W. L., and Streuter, M. A.: Carcinoma of the Maxillary Antrum, Surgery 35: 236, 1954. Tabb, H. G.: Maxillectomy in Carcinoma of the Antrum, Tr. Am. Laryngol. Rhinol. Otol. Sot. 59: 136, 1959. Ohngren, L. D.: Malignant Tumors of the Maxillo-ethmoidal Region, Acta. Otol. (Stockholm), Suppl. XIX, 1933. Ackerman, A. J.: The Prosthetic Management of Oral and Facial Defects following Cancer Surgery, J. PROS. DENT. 5: 413, 1955. Robinson, J. E.: Prosthetic Treatment after Surgical Removal of the Maxilla and Floor of the Orbit, J. PROS. DENT. 13: 178, 1963. Frazell, E. L.: The Surgical Treatment of Cancer of the Paranasal Sinuses, Laryngoscope 65: 557-567, 1955. Steadman, B. St. J.: Construction of Prostheses after Resection of the Maxilla, Int. Dent. J. 7: 560-561, 1957. Russell, 0.: Lecture Notes, Postgraduate series, Oct. 1965. Miglani, D. C., and Drane, J. B.: Maxillofacial Prosthetics and its Role as a Healing Art, J. PROS. DENT. 9: 159, 1959. Lingerman, R. E.: Lecture, Postgraduate Course, Maxillofacial Prosthetics, University of Indiana, 1965. Hammond, J.: Dental Care of the Edentulous Patient after Resection of the Maxilla, Brit. Dent. J. 120: 591, 1966. Giardino, C.: Le neoformazioni primitive delle osse mascellari, Minerva Stomatol., 15: 83-127, 1966. Richenbach, E.: Co-report: Prosthetic Treatment of Maxillofacial Defects, Internat. Dent. J. 8: 373, 1957. Coffin, F.: Cancer and the Dental Surgeon, Brit. Dent. J. 116: 191-202; 243-253, 1964. Nififfer, T. J., and Shipron, T. H.: The Hollow Bulb Obturator for Acquired Palatal Openings, J. PROS. DENT. 7: 126, 1957. Robinson, J. E.: Clinical Experiments and Experiences with Silicone Rubber in Dental Prosthetics, J. PROS. DENT. 13: 669, 1963. Gonzales, J. B., and Laney, W. R.: Resilient Materials for Denture Prostheses, J. PROS. DENT. 16: 438, 1966. Gibbons, P.: Clinical and Bacteriologic Findings in Patients Wearing Silastic 390 Soft Liners, J. Michigan Dent. A. 47: 65, 1965. Bascom, P. W.: Resilient Denture Base Materials, J. PROS. DENT. 16: 646-649, 1966. Sauer, J. L.: A Clinical Evaluation of Silastic 390 as a Lining for Dentures, J. PROS. DENT. 16: 650-660, 1966. Wilson, H. J., Tomlin, H. R., and Osborne, J.: Tissue Conditioners and Functional Impression Materials, Brit. Dent. J. 121: 9, 1966. FACULTY OF DENTISTRY UNIVERSITY OF TORONTO EDWARDS STREET TORONTO 2, CANADA