SURGICAL MANAGEMENT OF CYSTS AND CYSTLIKE LESIONS OF THE JAWS
Surgical management of oral pathologic lesions can best be discussed by broadly dassifying pathologic lesionsinto the following major categories cysts and cysrlike lesions of the jaws, benign tumors of the jaws, malignant tumors, and benign lesions of oral soft tissues.
If the cyst has not expanded or thinned the cortical plate, normal contour and firmness are noted. Palpation with firm pressure may. indent the surface of an expanded jaw with characteristic rebound resiliency. If the cyst
has eroded through the cortical plate, fluctuance may be .noted on palpation.
FIG. 22-1 Mandibular third molar is displaced by cyst.
Cysts of the jaws are treated in one of the following four basic methods: (1) enucleation, (2) marsupialization, (3) a staged combination of the two procedures, and (4) enucleation with curettage.
Enucleation is the process by which the total removal of a cystic lesion is achieved. By definition, it means a shellingout of the entire cystic lesion ‘without rupture. A cyst lends itself to the technique of enucleation because of the layer of fibrous connective tissue between the epithelial componen t
(which lines the interior aspect of the cyst) and the bony wall of the cystic cavity. This layer allows a cleavage plane for stripping the cyst from the bony cavity and makes enucleation similar to stripping periosteum from bone.
Advantages. The main advantage to enucleation is that pathologic’ examination of the entire cyst can be undertaken: Another advantage is that the initial excisional biopsy (i.e., enucleation) has also appropriately
treated the lesion. The patient does not have to care for a marsupial cavity with cons.tant irrigations. Once the mucoperiosteal access flap has healed, the patient is no longer bothered by the cystic cavity.
Disudvuntuges, If any of the conditions outlined under the section on indications for marsupialization exist, enucleation may be isadvantageous. For example, normal tissue may be jeopardized, fracture of the jaw could occur, devitalization of teeth could result, or associated impacted teeth that the clinician may wish to savecould be removed. Thus. each (;.:~tmust be addressed individually, and the clinician must weigh the pros and
cons of enucleation versus marsupializatiofl (with or without enucleation) (see discussion of Lnucleatlon after Marsupialization) .
‘In large cysts or cysts proximal to neurovascular structures, nerves and vessels are usually found pushed to one side of the cavlty by the slowly expanding cyst and should be avoided or handled as atraumatically and as little as possible. Once the cyst has been removed, the bony
cavity should be inspected for remnants of tissue. Irrigating and drying the cavity with gauze will aid in visualizing the entire bony cavity. Residual tissue is removed with curettes. The bony edges o.f the defect should be
smoothed with a file before closure.
Cysts that surround tooth roots or are in inaccessible areas of the jaws require aggressive curettage, which.Is necessary to remove fragments of cystic lining that could not. be removed with the bulk of the cystic wall. Should obvious devitalization of teeth occur during a cystectomy,
FIG. 22-2 A, Typical radiographic appearance of cyst. Radiolucent center is-surrounded
by zone of reactive bone. B, Expansion of buccal bone caused by underlying cyst. The
proximity to mental neurovascular bundle (on distal and inferior aspect of cystic expansron)
is demonstrated. C, Cystic cavity after removal of cyst is visualized. Mental nerve is
left Intact. The amount of osseous tissue is destroyed by cyst.
FIG. 22-2-cont’d D, Cyst with buccal bone still attached, E, Mucosal closure is demonstrated.
endodontic treatment of the teeth may be necessary in the near future, which may help to prevent Odontogenic infection of the cystic cavity from the necrotic dental pulp.
Marsuplallzatton, decompression, and the Partsch operation all refer to creating a surgical window in the wall of’ the cyst, evacuating the contents of the cyst, and maintaining continuity between the cyst and the oral cavity, maxillary sinus, or nasal cavity (Fig. 22-5). The only portion
of the cyst that is removed is th, piece removed toproduce the window. The remaining cystic lining is left in situ, This process decreases intracystic pressure and promotes shrinkage of the cyst and bone fill. Marsupialization
can be used either as the sole therapy for a cyst oras a preliminary step in management, with enucleation deferred until later.
FIG. 22·3 Multilocular appearance of cyst. This lesion was diagnosed
histologically as odontogenic keratocyst.
the inferior alveolar nerve) or devitalization of healthy
teeth, marsupialization should be considered.
2. Surgical access. If access. to all portions of the cyst is difficult,
portions of the cystic wall may be left behind,
which could result in recurrence. Marsupialization
should therefore be considered.
3. Assistance ill eruption of teeth. If an unerupted tooth
that is needed in the dental arch is involved with the
cyst (i.e., a dentigerous cyst), marsupialization may
allow its continued eruption into the oral cavity (Fig.
4. Extent of surgery. In an unhealthy or debilitated
patient, marsupialization is a reasonable alternative to
enucleation, because it is simple and may be less stressful
for the patient .
. S. Size of cyst. In very -large cysts, a risk of jaw fracture
during enucleation is possible. It may be better to marsupialize
the cyst and defer enucleation until after
considerable bone fill has occurred.
Advaut aec», The main advantage of marsupialization
is that it is a simple procedure to perform. It may also
spare vital structures from damage should immediate
enucleation be attempted.
FIG. 22·4 Apical cystectomy performed at time of tooth removal. A to C, Removal with curette via
tooth. socket is visualized. A apical cystectomy must be performed with care because of proximity of
apices of teetn to other structures, such a5 maxillary sinus and inferior alveolar canal.
al times every day with 11 syringe. This may continue for several months, depending on the size of the cystic cavity and. the rate of bone fill.
FIG. 22-4-cont’d Dto” Removal of apical cyst by flap reflection and creation of osseous window
is demonstrated -at the time of tootlt removal
the area, the cyst is aspirated as discussed in Chapter 20. If the aspirate confirm’s the presumptive diagnosis of a cyst, the marsupialization procedure may proceed (Fig. 22-7). The initial incision j.s usually circular or elliptic and creates a large (1 em or larger) window into the cystic cavity. If the bone has been expanded and thinned by the cyst, the initial incision may extend
FIG. 22-5 Marsupialization technique. A, Cyst within maxilla. B, Incision through oral mucosa and
cystic wall into center of cyst. C, Scissors used to complete excision of window of mucosa and cystic
wall. D, Oral mucosa and mucosa of cystic wall sutured together around periphery of opening.
case the tissue contents of the window are submitted for pathologic examinatlon. If the overlying bone is thick, an osseous’ window is removed carefully with burs and rongeurs. The cyst is then incised to remove a
window of the lining, which is submitted for pathologic examination. The contents of the cyst are evacuated, and, if possible. visual examination of the residual Iining of the cyst is undertaken. Irrigation of the cyst
removes any residual fragments of debris. Areas or ulceration or thickening of the cystic wall should alert the clintcia I to tile possibility of dysplastic or neoplastic changes ill tile wall of tile cyst. In this instance enucleation of the entire cxst or incisional biopsy of the suspicious area or.
areas should be undertaken. If the cystic lining is thick enough and if access permits, the perimeter of the cystIC wall around the window ‘can be sutured to the oral. Otherwise the cavity should be packed with
strip gauze il.ll’regnated with tincture of benzoin or an antibiotic ointment. This packing must be left in place for 10 to 14 days to prevent the oral mucosa from healing healing over the cystic window. By 2 weeks the lining of the cyst should be healed to the oral mucosa around the periphery of the window.
FIG. 22-6 Marsupialization of multiple dentigerous cysts. A, Radiographic appearance before marsupialization.
Marsupialization was carried out along crest of alveolar process on both sides. 8, One
year later, the uprighting and sruptlon.of teeth are demonstrated. C, Three years later. No orthodontic
assistance was. required. (From Ellis E, Fonseca RJ: Therapy of cysts and odontogenic tumors. In
Thawley SE et al, editors: Comprehensive management of head and neck tumors, ed 2, Philadelphia,
1999, WB Saunders; courtesy qr. TImothy Pickens, Ypsilanti, MI.)
FIG. 22-7 This case combined marsupialization with subsequent enucleation. A, Radiographic
appearance of lesion and displaced tooth on initial examination. 8, Mucosa reflected from
anterior border of ascending ramus. Osseous window created by use of round bur; bone w~s
gently removed, exposing underlying fibrous cystic wall (white membrane). Circular. piece of
this cystic wall was removed, exposing cystic lumen. Cystic mucosa was then sutured to oral
mucosa around periphery of osseous window. Osseous window and cystic specimen were submitted
for pathologic examination
Marsupialization is rarely used as the sole form of treatment for cysts. In most instances enucleation is done after marsuplalization. In the case of a dentigerous cyst, however, there may not be any residual cyst to remove
once the tooth has erupted into the dental arch. In addition, if furthercontraindicated because of concornltant medical problems. marsupialization may be performed without tuture enucleation. The cavity mayor may not obliterate totally with time. If it is kept clean,
the cavity should not problem.
Enucleation after Marsupialization
Enucleation is frequently done (at a later date) after marsupialization. Initial healing is rapid after marsupiaization, but the size of the cavity may not decrease appreciably past a certain point. The objectives of the marsupialization procedure have been accomplished at this time
and a secondary enucleation may be undertaken without injury to adjacent structures. The combined approach reduces morbidity and accelerates complete healing 0 the defect.
‘FIG~ 22-7-cont’d C, Appearance at 13 months of opening created into cyst, The patient
had irrigated lumen twice a day, 0, Radiographic appearance at -13 months, The extent of bone
regeneration (compared with Fig, 21-7, A) is visualized,-Now ample osseous tissue surrounds
inferior alveolar neurovascular bundle to prevent damage during enucleation,
Advantages, The advantages of combined marsupialization and enucleation are the same as those listed for marsupialization and enucleation. In the marsupialization phase, the advantage is that this is a simple procedurethat
spares adjacent vital structures. In the enucleation phase, the entire lesion becomes available for histologic examination, Another advantage is tile development of a thickened cystic lining, which makes the secondary enucleation an easier procedure.
Technique, The cyst is first marsupialized, and osseous healing is allowed to progress. Once the cyst, has decreased to a size that makes it amenable to complete surgical removal, enucleation is performed as the definitive treatment. The appropriate time for enucleation is when bone is covering adjacent vital structures, which prevents their injury during enucleation, and when adequate bone fill has provided enough strength to the jaw to prevent fracture during enucleation (se Fig. 22-7).
FIG. 22-7-cont’d E, Cystectomy easily performed .13 months after initial marsupialization.
Tooth being removed with cystic ‘rail. The thickness 01cystic wall is demonstrated. F, Specimen
Once the cyst has been enucleated, the oral soft tissues must be closed over the defect, if possible, which may require the development and mobilization of soft tissue flaps that can be advanced and sutured in a watertight manner over the osseous window. If complete closure of’
the wound cannot be achieved, packing the cavity with strip gauze impregnated with an antibiotic ointment is acceptable. This packing must be changed repeatedly with cleansing of the cavity until granulation tissue has obliterated the opening and epithelium has closed over the wound.
Encleation with Curettage
Enucleation with curettage means that after enucleation a curette or bur is used to remove 1 to 2 mm of bone around the entire periphery of the cystic cavity. This is done to • remove any remaining epithelial cells that may be present in the periphery of the cystic wall or bony cavity. These
cells could proliferate into a recurrence of the cyst.
Tcctmique. After the cyst has been enucleated and removed, the bony cavity is inspected for proximity to adjacent structures. A sharp curette or a bone bur with sterile irrigation can be used to remove a 1- to 2-mm layer
of bone around the complete periphery of the cystic cavity. This should be done with extreme care when workingproximal to important anatomic structures. The cavity is then cleansed and closed.