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Maxillary Reconstruction With BoneTransport Distraction and Implants After

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Maxillary and mandibular bone defects can result from injury, congenital defect, or accident, or as a con-
sequence of surgical procedures when treating pathology or defects affecting jaw bones. The glandularodontogenic cyst is an infrequent type of odontogenic cyst that can leave a bony defect after being treated

by aggressive surgical means. First described in 1987 by Padayachee and VanWyk, it is a potentially aggres-

sive entity, having a predisposition to recur when treated conservatively, with only 111 cases having been

reported hitherto. Most reports emphasize its clinical, radiographic, and histologic features, including

a few considerations on rehabilitation for these patients. The aim of this article is to present the case of

a 24-year-old male patient who, in 2001, was diagnosed with a glandular odontogenic cyst and to focus

on the surgical approach and rehabilitation scheme. We performed an anterior partial maxillectomy.

The osseous defect was treated using bone transport distraction. Dental and occlusal rehabilitation wasachieved with titanium implants over transported bone and an implant-supported overdenture. A 9-year

follow-up shows no evidence of recurrence of the pathology, adequate shape and amount of bone, func-

tional occlusal and dental rehabilitation, and patient’s satisfaction.

� 2013 American Association of Oral and Maxillofacial Surgeons

J Oral Maxillofac Surg 71:e137-e142, 2013

Maxillary and mandibular bone defects can result from

injury, congenital defect, or accident, or as a conse-

quence of surgical procedures. The glandular odonto-genic cyst (GOC) is an infrequent type of odontogenic

cyst counted among the pathologies that can leave

a bony defect after being treated by aggressive surgical

means.

GOC was first reported in the English literature in

1987 when Padayachee and Van Wyk1 described 2

multilocular mandibular cysts and speculated on the

possibility of salivary gland origin, thus suggestingthe term sialo-odontogenic cyst. The following year

Gardner, Kessler, Morency, and Schaffner2 reported 8

more cases and proposed the term GOC. Four years

later the World Health Organization included this

pathology in its typing of odontogenic tumors.3

GOC is an exceedingly rare odontogenic cyst

of the jaw bones; it shows a high tendency to

rom the Universidad El Bosque, Bogot�a, Colombia.

nt, Oral and Maxillofacial Surgery

Surgeon, Division ofOral andMaxillofacial Surgery, Cl�ınica

lsubsidio and Assistant Professor, Department of Oral and

ial Surgery

s correspondence and reprint requests to Dr Castro-

alle 63 #7A-44, Monter�ıa, Colombia, South America.

[email protected]

erican Association of Oral and Maxillofacial Surgeons

/12/7008-0$36.00/0

oi.org/10.1016/j.joms.2012.08.030

e137

recur when treated conservatively.4,5 It exhibits

a definite predilection for the anterior portion of the

mandible.4-7 Radiographically, it presents as eithera unilocular or multilocular radiolucent lesion with

well-demarked borders,8 and histologically, it is charac-

terized by a cyst wall lining of nonkeratinized epithe-

lium with papillary projections, nodular thickenings,

and mucous-filled clefts, as well as the presence of vari-

able numbers of mucous-secreting cells in the surface

layer of the epithelium.3-4,9

The most recently published review of the literatureidentified 111 cases.9 Our literature review found that

most reports of GOC emphasize its clinical, radio-

graphic, and histologic features, with little mention

of the treatment plan and final rehabilitation for the

patients targeted by this unpredictable, potentially

aggressive cyst.10-13 In this article, we present the

case of a 24-year-old male patient diagnosed with

GOC. We focus on the rehabilitation plan accom-plished with bone transport distraction, titanium

implants over transported bone, and an implant-

supported overdenture.

Case Report

On October 2, 2001, a 24-year-old man who was

born and raised in Bogot�a presented to the Oral andMaxillofacial Surgery Division at Cl�ınica Infantil Col-

subsidio in Bogot�a, Colombia. The chief complaint

was a large swelling in the anterior portion of the

hard palate of 5 days duration. He associated the lesion

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mailto:[email protected]

http://dx.doi.org/10.1016/j.joms.2012.08.030

FIGURE 1. The panoramic radiograph shows a well-defined, ra-diolucent, unilocular lesion from 6 to 10 with scalloped bordersand rhizolysis of the mentioned teeth (arrows).

Castro-N�u~nez and Gonz�alez. Maxillary Reconstruction After Par-tial Maxillectomy. J Oral Maxillofac Surg 2013.

FIGURE 2. The healing surgical site.


e138 MAXILLARY RECONSTRUCTION AFTER PARTIAL MAXILLECTOMY

with a traumatic injury. Inquiry into the patient’s med-

ical history showed that he was a healthy person who

was not taking any medications at the time of the

appointment.

Intra-oral examination found a painful, rounded,

2.5 cm of diameter mass located on the midline of the

hard palate. The mass, which was fluctuant and ery-

thematous, had a pustule buccal to tooth 8. The masscreated not only an evident deformation of the contour,

but also plus II mobility of upper right central incisor

and upper left central incisor, the latter being painful

to percussion as well. Palpation of the cervical area

showed no lymphadenopathy. Vital signs were as fol-

lows: bloodpressure 120/80 mmHg, heart rate 75beats

per minute, 19 per minute, and temperature 37�C.He presented with a periapical radiograph of the an-

terior superior incisives taken a few days earlier in the

Division of Endodontics. The image showed a radiolu-

cent, unilocular lesion apical to teeth 8 and 9. The

clinical provisional diagnosis was ameloblastoma.

The differential diagnosis included central giant-cell

granuloma, odontogenic keratocyst, and central

mucoepidermoid carcinoma. The necessity of both

a panoramic radiograph and a biopsy to confirm thediagnosis and determine treatment options was

explained to the patient. He agreed to the biopsy but

refused to be exposed to additional radiation.

In the operating room, under local anesthesia with

lidocaine 1:80,000 epinephrine, an incisional biopsy

was performed in the hard palate from teeth 8 to 10.

The sample was sent to the pathology division for anal-

ysis. It was reported as being a glandular odontogeniccyst. During the next 2 months, several attempts were

made to contact the patient, but he failed to answer

phone calls or return to the Oral and Maxillofacial

Surgery Division.

Six months later, the patient entered the emer-

gency room with excruciating pain at the same

site with a deformation of contour on both palatal

and vestibular surfaces, palatal tumefaction, and la-bial edema that caused facial asymmetry. The emer-

gency treatment included drainage of the lesion,

resulting in the collection of 15 mL of hematopuru-

lent material. A panoramic radiograph taken the

next day showed a well-defined, unilocular, radiolu-

cent lesion with scalloped borders and rhizoly-

sis (Figure 1).

In 2002, as it seems to be today, there was no clarityabout the best method of treating GOC, with authors

recommending both conservative10,14 and aggressive

approaches.15-16 We proposed the following: 1)

surgical approach in the form of partial anterior

maxillectomy, 2) construction of a temporary

removable partial denture, 3) bone transport

distraction, 4) endosseous implants over transported

bone, and 5) implant-supported overdenture.

On the basis of the clinical presentation of the case,

histopathology, and literature review, the patient un-

derwent a partial anterior maxillectomy, includingteeth 6 to 10, under general anesthesia. Margins in

the resection were 1 cm. The removed fragment mea-

sured 4.0 cm x 3.5 cm, and 2 cm in depth. There was

no oroantral communication. The wound was closed

in layers and healed uneventfully (Figure 2). The spec-

imen was sent to the Division of Pathology, where it

was stained with hematoxylin-eosin. Microscopic ex-

amination of the tissue showedmultilocular cystic cav-ities infiltrating adjacent bone. The cavities were lined

by nonkeratinized, stratified, squamous epithelium.

The presence of whorls of epithelial cells containing

mucous-secreting (glandular) cells was found. The

pathologist’s diagnosis was glandular odontogenic

cyst. On final pathologic sections, resected margins

were free of cyst.

The patient returned for surgery after a 5-monthhealing period. Under general anesthesia, a transport

FIGURE 4. Distractors in place. The arch bar was removed beforesurgery to facilitate distractor placement.


CASTRO-N�U~NEZ AND GONZ�ALEZ e139

segmental osteotomywas carried out in order to place

2 bone distractors (Dynaform, Leibinger, Kalamazoo,

MI). On raising a mucoperiosteal flap in the vestibule,

vertical osteotomies were made distal to teeth 4 and

12, and bone distractors placed simultaneously on

both sides using 2 transport plates. The vestibular mu-

coperiosteum was maintained attached to the trans-

port segments. Devices used had 2 lower arms thatwere attached to the neck of the teeth with wires

and 2 upper arms that were fixed to the bone using

2.0 mm by 7.0 mm screws. In order to guide and con-

trol the direction of the vector and to diminish the

pressure of the soft tissues over transport segments,

a band-sported orthodontic arch was constructed

and cemented (Figures 3 and 4). The healing process

was uneventful.Distraction phase started after a 7-day latency period

at a rate of 0.5 mm in the morning and 0.5 mm at night

for a total of 1.0 mm per day, achieving 11.05 mm dur-

ing 11 days. The distractor was left in place for 3

months to allow consolidation (Figures 5 and 6) and re-

moved under local anesthesia. A panoramic radio-

graph showed the success of the technique with

newly formed bone. Because bony union in the mid-line was not achieved, another distractor (Dynaform,

Leibinger) was used to reduce the size of the gap. Final

gap closure was accomplished using an iliac crest

bone graft secured withminiplates, and themucosa re-

positioned without tension (Figures 7 and 8). An unde-

sirable side effect of distraction osteogenesis (DO) was

the loss of osseous support of teeth 4, 5, 11, and 12.

The teeth were eventually extracted because they af-fected both esthetics and function.

FIGURE 3. A band-sported orthodontic arch was constructed andcemented to guide bone distractors to diminish the pressure of thesoft tissues over the transport segments. Arch bar is in position beforedistractor placement. After raising a mucoperiosteal flap in the ves-tibule (arrows), vertical osteotomies were made distal to teeth 4and 12.


Three months later, 6 titanium implants to replaceteeth 6, 7, 8, 9, 10 were placed in the newly formed

maxillary ridges, achieving excellent primary stability

(Figure 9). Final prosthetic rehabilitation consisted

of an implant-supported overdenture (Figure 10). A

9-year follow-up period shows no evidence of recur-

rence of the pathology, complete bone union at the

docking site, adequate shape and amount of bone,

functional dental and occlusal rehabilitation, and pa-tient satisfaction (Figures 11 and 12).

Discussion

GOC is considered a rare, aggressive lesion of the

jaw bones with unusual histopathologic features and

high recurrence rate when treated conservatively.14-21

Its frequency ranges from 0.012%17 to 1.3%22, and its

prevalence is as low as 0.17%.23 There is a slightmale predilection, and lesions occur mainly in the

mandible of middle-aged persons.9,18,24 The most

common clinical presentation is a painless swelling

in the face associated with the anterior mandible.

FIGURE 5. A new distractor was collocated in the midline to re-duce the size of the gap.


FIGURE 6. Results after the distraction phase.


FIGURE 8. The mucosa repositioned without tension.



Radiographically, it can present as either a unilocular

or multilocular radiolucent lesion usually large in size.8

The literature offers many options for GOC, ranging

from conservative to aggressive methods. Despite the

fact that GOC’s tendency to recur when treated con-servatively was noted by Gardner and Morency in

19935, clinicians seemed to favor conservative

methods, such as excision, enucleation, curettage,

and extirpation.10,14,20,25 In 1995, however, Hussain

et al,15 advocated for en bloc excision and primary re-

construction to ensure cure.

Recurrence, which ranges from 29% to 55%,4 is

thought to be due to the thin capsule, presence ofmicrocysts that canmake complete removal a challeng-

ing task19 and invasion through medullar spaces.15,26

Therefore, recurrence is related not only to the

biology of the lesion, but also to the type of treatment

FIGURE 7. Final gap closure was accomplished using iliac crestbone graft secured with miniplates.


chosen.11,15,18 This observation played a key role inthe shift noted during the mid- to late-2000s toward

the more radical methods that are in vogue

today.4,9,12,16,18,19 In 2002, when we decided to treat

our patient by means of partial maxillectomy, many

authors advocated for conservative options. Our first

consideration was enucleation, but as we took into

account the size of the lesion, the condition of the

cortical plates, the rhizolysis, the high recurrencerates when using enucleation or other conservative

procedures, and the patient’s possible negligence to

return periodically for follow-up appointments, it be-

came clear that the best surgical approach for him

was a partial maxillectomy and reconstruction of the

defect using bone transport distraction, titanium

implants, and an implant-supported overdenture.

FIGURE 9. Endosseous implants in place.


FIGURE 10. Final appearance of the patient.


FIGURE 12. Appearance of the patient 9 years later at a follow-upappointment.


CASTRO-N�U~NEZ AND GONZ�ALEZ e141

DO is a biologic process through which new bone isgenerated through incremental lengthening of osseous

segments.27-29 During the past decade, this technique

has gained acceptation among clinicians for the

correction of bony defects. It not only avoids the

drawbacks of the maxillary obturator prosthesis (eg,

instability and incomplete seal)30 but also consum-

mates a concomitant increase in the alveolarmucosa,31

and in most cases, eliminates bone and soft tissuegrafts, thereby avoiding donor site morbidity.32-33

After a successful DO is achieved, titanium implants

can be placed, being the treatment of choice for

restoring function and esthetics.29-31,34

As we pointed out earlier, most articles regarding

GOC concentrate on its biologic behavior, histopatho-

logic, and radiographic features, and whether conser-

vative or aggressive surgical approaches should beused for its removal. To the best of our knowledge,

a very small number of papers report or discuss on

FIGURE 11. Appearance of the patient before surgery.


the rehabilitation phase for these patients. Hussain

et al,15 for example, treated their fourth case by wideresection of the lesion and reconstructed the body of

the mandible with contoured rib graft secured with

miniplates. Ch�avez and Richter16 treated their case

by resecting the lesion including 1 cm bony and soft

tissue margins with immediate reconstruction with

free-fibular graft and a reconstruction plate. For final

rehabilitation, they considered osseointegrated im-

plants. In 2006, Thor et al,4 reported a case in whicha marginal resection was performed and reconstruc-

tion with particulated bone graft, platelet-rich plasma,

vertical alveolar distraction, titanium implants, and fi-

nal prosthetic rehabilitation. More recently, in 2010,

Fujioka et al,35 published the case of a patient with

a maxillectomy defect (not caused by GOC) in which

bone transport distraction and dental implants were

used successfully.First introduced by orthopedists for lengthening

long bones,27 DO in the maxillofacial complex was

initially used to correct mandibular deficiencies and

advancement of maxilla and midface.36 In the dentoal-

veolar area, it was used to reconstruct vertical alveolar

defects and, later, in other situations (ie, advancing the

anterior maxilla, accelerating orthodontic treatment,

resolving dental crowding).37-40 Although thetechnique is used to reconstruct a myriad of clinical

situations and appears to be well tolerated, DO is not

without its drawbacks. Complications associated

with this procedure include fractures of basal bone,

fracture of transport segment, breakage of distractor,

mechanical problems, and infection.41-42

The current number of reported cases of GOC is

small. Therefore, many doubts exist about its biologi-cal behavior and treatment methods. Recurrence is re-

lated mainly to 2 factors: biology of the lesion and

incomplete removal of the lining after conservative

treatment. Rehabilitation methods and techniques

used to correct the bony defect created by surgical


resection are not well documented, with only a few pa-

pers discussing this important topic. In this case, tita-

nium implants over distracted bone are reported to

be a reliable method for reconstructing the bony de-

fect created by a partial maxillectomy. This case will

add to the existing knowledge of GOC by providing

valuable information on a successful reconstruction

scheme after partial maxillectomy.

Acknowledgments

Wewant to thank Drs James Haljun, Ana Isabel Roselli, Clara Mor-eno, and David Rey Berm�udez. Many thanks to Kathryn Pope, RosaGarza-Mourino, and David Tripp at Antioch University, Los Angeles,CA. We are in great debt to Glenna Castro-N�u~nez for her fantastic jobwith pictures and artwork.

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maxillary reconstruction with bone transport distraction and implants after partial maxillectomy

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