Keywords Interdisciplinary care - melanotic neuroectodermal tumor of infancy - modification
- obturator - time-saving
Introduction
Melanotic neuroectodermal tumor of infancy (MNTI) has been categorized as “rare clinical
entity” by “Office of Rare Diseases” of National Institute of Health. It is a melanin-producing
neoplasm which primarily affects maxilla during 1st year of life.[1 ]
Although benign, MNTI has been documented to be locally aggressive, resulting in tooth
displacement, adjacent bone invasion, and impairment of oral functions such as feeding
and sucking.[2 ] Multidisciplinary management includes surgical removal of the tumor mass followed
by restoration of oral function with an obturator.
The current report is documentation of novel, simple, and practical approach in the
fabrication of an obturator in a growing child.
Case Report
Previous medical history
A 2½-month-old infant presented with sudden onset and progressive left facial swelling.
A 3 cm × 3 cm well-circumscribed, nonfluctuant mass was seen in the left maxilla,
protruding into oral cavity. Computerized tomographic scan revealed an expansive lytic
lesion involving left maxilla associated with significant peripheral sclerosis and
displacement of deciduous teeth.
Incisional biopsy was indicative of MNTI. Immunohistochemical (IHC) analysis was positive
for HMB-45 and cytokeratin and equivocal for S-100.
In view of vast tumor spread and focal areas of ulceration, radical surgery was planned.
Left total maxillectomy was carried out, and surgical defect was lined with partial
thickness skin graft. On sufficient healing, an interim maxillary obturator was given
to the patient.
At present, the patient reported to the department at an age of three, with his parents
with a complaint of nasal seepage of liquids due to lack of retention of the obturator.
Examination
Intraoral examination revealed well-healed, skin graft-lined total maxillectomy defect
on left side [Figure 1 ]. Deciduous canine and molars had erupted with evidence of erupting deciduous right
central incisor. The existing obturator had become loose owing to infantile growth
spurt. Eruption of deciduous teeth had rendered an incomplete seating of the obturator.
Figure 1: Intraoral view of well‑healed maxillectomy defect with red circle showing
erupting deciduous incisor
Procedure of fabrication of an interim obturator
Existing obturator was duplicated in form and used as a custom tray [Figure 2 ]. Height of the bulb was reduced, and tray was relieved all around by 1–1.5 mm. A
handle was attached to enable accurate and convenient seating in the mouth.
Figure 2: Custom tray obtained by duplicating the existing prosthesis
The tray was verified for border extensions, and impression of maxillectomy defect
was made with polyvinyl siloxane (PVS) impression material (Aquasil Soft Putty™ and
Aquasil LV™, Dentsply International, Pennsylvania, United States). Putty material
was molded and placed on the bulb and light body PVS loaded onto remaining portion
of the tray. A thin layer of light body material was applied over putty to record
fine details of the defect. The child was stabilized and tray carefully placed in
the mouth. On reaching final set of the material, the impression was removed from
the mouth and inspected for errors and inaccuracies [Figure 3 ]. It was poured in Type III dental stone (Ultrastone™, Kalabhai Pvt. Ltd., Mumbai,
India) to obtain master cast [Figure 4 ]. The defect area was outlined on the cast and medial undercut was blocked. Subsequently,
an interim maxillary obturator was fabricated in polymethyl-methacrylate resin (DPI
Heat Cure, Dental Products of India Pvt Ltd., Mumbai, India). A relief was designed
in the obturator to accommodate erupting deciduous right central incisor [Figure 5 ]. The obturator was finished, polished, and delivered to the patient [Figure 6 ]. Parents were instructed about maintenance of the prosthesis and importance of regular
follow-up visits to facilitate frequent adjustments.
Figure 3: Definitive elastomeric impression
Figure 4: Master cast
Figure 5: Final prosthesis with red circle showing provision to accommodate erupting
deciduous incisor
Figure 6: Interim obturator in situ
Discussion
MNTI is a rare clinical entity and usually affects infants in first 6 months of life
with a mean age of presentation of 4.3 months.[3 ]
[4 ] It has no gender predilection though Kruse–Losler reported a male-to-female ratio
of 1.48.[5 ] It is a rapidly-growing, nonulcerative enlarging mass that usually affects anterior
maxilla. It has also been reported in other sites of head and neck region such as
skull, mandible, and brain.[4 ]
Many investigators have proposed numerous theories regarding tumor histogenesis which
has resulted in its varied nomenclature.[6 ]
[7 ]
[8 ]
[9 ]
[10 ] Current nomenclature of MNTI which reflects its neural crest cell origin is widely
accepted and recognized by WHO.[11 ]
Radiologically, the tumor is osteolytic in appearance with adjoining deciduous teeth
appearing to be “floating” within the lesion.[12 ]
Histologically, it shows dual cellular pattern with large melanin-containing polygonal
cells arranged in alveolar or tubular structures and small neuroblast-like cells with
hyperchromatic nucleus and scanty neoplasm in dense fibrous stroma. IHC markers such
as HMB-45, neuron specific enolase, CD 56, synaptophysin, and chromogranin have been
proposed to have a positive association with MNTI.[6 ]
Despite aggressive clinical presentation, the prognosis is good and curative surgery
is treatment of choice. The probability of recurrence is maximum in first 6–18 months;
hence, periodic follow-up is highly recommended.[1 ] The presented case has been on regular follow-up since 3 years and shown excellent
locoregional control.
Multidisciplinary management of MNTI is essential as radical surgery impairs essential
oral functions such as feeding, mastication, and speech. Interdisciplinary care reduces
posttreatment morbidity by providing efficient rehabilitation during critical growth
period of the pediatric patient.[13 ]
Maxillary obturator helps in restoring palatal contours and sealing margins of maxillary
defect.[13 ] The exercise of recording maxillary defect during dual impression-making can be
quite tedious and traumatic for a pediatric patient. In this report, existing obturator
was duplicated and sufficiently relieved to act as a custom tray. This was time-saving
and allowed us to forego the procedure of making preliminary impression. In addition,
it enabled the construction of a well-fitted custom tray which was well tolerated
by the child. Such procedural modification greatly improved patient compliance and
facilitated prosthesis delivery within a day. An opening was created in the prosthesis
corresponding to erupting deciduous incisor to allow unimpeded eruption.
Conclusion
The current report throws light on the significance of interdisciplinary management
of a rare pediatric solid tumor such as MNTI. A simple, practical, and time-saving
procedural modification in the fabrication of obturator for a pediatric patient has
been presented. In addition, it stresses on the need to accommodate erupting teeth
by necessary adjustment of the prosthesis which is critical in a growing child.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms.
In the form the patient(s) has/have given his/her/their consent for his/her/their
images and other clinical information to be reported in the journal. The patients
understand that their names and initials will not be published and due efforts will
be made to conceal their identity, but anonymity cannot be guaranteed.
