A 32-year-old woman presented with swelling on the right side of her mandible. Imaging showed a multilocular lesion involving the angle, ramus, and part of the right body. Biopsy confirmed ameloblastoma. The patient underwent partial resection of the mandible with a titanium plate reconstruction planned using stereolithography. Stereolithography was used to create a precise 3D model of the resection area from CT scans for preoperative planning and plate fitting. The surgery and reconstruction were performed using the presurgically planned and fitted plate, demonstrating the value of stereolithography for complex mandibular reconstruction planning and implementation.

1. ISSN 1807-5274
Rev. Clín. Pesq. Odontol., Curitiba, v. 4, n. 2, p. 101-105, maio/ago. 2008
©Revista de Clínica e Pesquisa Odontológica
APPLICATION OF STEREOLITHOGRAPHY IN
MANDIBULAR RECONSTRUCTION FOLLOWING
RESECTION OF AMELOBLASTOMA: case report
Aplicação da estereolitografia na reconstrução mandibular após ressecção de
ameloblastoma: relato de caso
Camila Lopes Cardoso1, Etiene de Andrade Munhoz2, Eduardo Dias Ribeiro3,
José Bonifácio de Souza Neto4, Eduardo Sant’Ana5, Osny Ferreira Júnior6
1
DDS, MSc student, Department of Stomatology, Bauru Dental School, University of São Paulo, Bauru, SP - Brazil.
2
DDS, MSc, PhD student, Department of Stomatology, Bauru Dental School, University of São Paulo, Bauru, SP - Brazil.
3
DDS, Oral and Maxillofacial Surgeon, Bauru Dental School, University of São Paulo, Bauru, SP - Brazil, e-mail:
eduardodonto@yahoo.com.br
4
DDS,Oral and Maxillofacial Surgeon, Bauru, SP - Brazil.
5
DDS, PhD, Oral and Maxillofacial surgeon, Department of Stomatology Bauru Dental School, University of São Paulo, Bauru,
SP - Brazil.
6
DDS, PhD, Professor, Department of Stomatology, Bauru Dental School, University of São Paulo, Bauru, SP - Brazil.
Abstract
A 32-year-old female patient complaining about swelling in the right side of the mandible was
referred to our Institution. Clinical exam showed erythema and crepitation during palpation in the
region. CT showed a multilocular lesion involving the angle, ramus and part of the right body of
the mandible. Incisional biopsy confirmed the diagnosis of ameloblastoma. The surgical treatment
performed was partial resection with safety margin and reconstruction with titanium plaques. The
reported case describes, in details, the application of stereolithography for presurgical planning of
mandibular reconstruction following resection of ameloblastoma.
Keywords: Stereolithography; Mandibular reconstruction; Rapid prototyping; Ameloblastoma.
Resumo
Paciente de 32 anos, sexo feminino, com queixa de aumento de volume no lado direito da
face, foi indicada para nossa instituição. Ao exame clínico, apresentou tumoração no lado
direito do corpo mandibular, eritema e crepitação à palpação da região. TC revelou lesão
Rev Clín Pesq Odontol. 2008 maio/ago;4(2):101-105

2. 102 Cardoso CL, Munhoz EA de, Ribeiro ED, Souza Neto JB de, Sant’Ana E, Ferreira Júnior O.
multilocular comprometendo o ângulo, ramo e parte do corpo mandibular direito. O exame
microscópico da lesão apresentou diagnóstico de ameloblastoma. O tratamento cirúrgico foi
ressecção parcial da mandíbula com margens de segurança e reconstrução com placa de
titânio. Descreve-se o planejamento cirúrgico da reconstrução mandibular, utilizando a
estereolitografia no planejamento.
Palavras-chave: Estereolitografia; Reconstrução mandibular; Prototipagem rápida;
Ameloblastoma
CASE REPORT Design). With the aid of a CAM (Computer Aided
Manufacturing) system, and specific equipment,
A 32-year-old white female patient the physical model was built. The equipment
complaining of swelling on the right side of the consists of a tank filled with acrylic resin, epoxy
face was referred to our institution. Extraoral or vinyl, constituted by monomers, photo-
examination revealed a slight asymmetry on the initiators and additives. The model is built on a
right side of the mandible. The patient reported mobile platform situated immediately below the
suppuration in the region of mandibular molars. surface of this tank.
Erythema and crepitation during palpation in the The computer sends to the platform the
region were found on clinical examination. The first layer of the virtual model to be polymerized.
CT showed 4 cm in diameter multilocular When this layer is hit by the laser, photo-initiators
radiolucent lesion, compromising angle, ramus trigger a localized reaction that fosters the
and part of the right body of the mandible, formation of a polymeric chain between the
delimited by moderately irregular margins. monomer’s molecules dispersed in the resin and
Aspiratory punch and incisional biopsy were solidification takes place.
carried out for microscopic examination. The An elevator dives the platform in the
microscopic diagnosis was compatible with liquid polymer bath and the laser beam creates the
ameloblastoma, following a follicular microscopic second layer of solid polymer on top of the first
pattern. layer. The numerical control of the machine
A partial resection of the mandible in the positions this platform on the surface of the resin
area affected by the lesion was planned with adequate and galvanometric mirrors directs the laser beam
safety margins. A prototype or model of the area to to the portion of resin corresponding to this first
be reconstructed was chosen, through the layer. The process is repeated successively until
stereolithography method (rapid prototyping type). the prototype is complete. Once ready the solid
In order to obtain models through this model is removed from the liquid polymer bath
technique the helicoidal computerized tomograph and washed. The supports are removed and the
should obtain reformatted axial cuts of about 1,0 model is placed in an ultraviolet radiation oven to
mm in thickness to reproduce precisely all the undergo a complete polymerization.
details captured. After the image is captured, With the model in hands, precise
following the prototype manufacturer’s measurements were obtained, which were
requirements, specific programs generate a virtual transferred to the patient with extreme precision.
three-dimensional model which is utilized in the Therefore, it provided a tactile perception of the
real model reconstruction process. lesion. Modeling and adaptation of the
In the case at issue, the program used reconstruction plaque, in the 2.7mm system, were
was the 3D CAD system (Computer Aided performed from the model (Figure 1).
Rev Clín Pesq Odontol. 2008 maio/ago;4(2):101-105

3. Application of stereolithography in mandibular reconstruction following resection of ameloblastoma 103
FIGURE 1 - Plaque modelling and adaptation
Resection of the lesion with safety margins
was performed and the previously molded FIGURE 3 - Final computerized tomography
reconstruction plaque was installed (Figure 2 e 3).
DISCUSSION
Ameloblastoma is classified as a benign
odontogenic tumor, although its behavior is similar
to that of true neoplasia, for being locally invasive,
aggressive and leads to a radical treatment planning,
since the conservative ones has recurrence reports
(1, 2). The prognosis of the solid pattern is obscure;
thus, the treatment of choice is generally radical.
Due to the relapsing potential, in the face of great
resections, the patients seek a treatment with
functional and aesthetic results. Hence, the
planning requires new technologies in the
reconstruction techniques.
Technological advances in image
collection, through more and more developed
plans such as helicoidal computerized tomography,
FIGURE 2 - Installation of premolded plaque have allowed the creation of a prototype or model
construction technology, in a reduced time, known
as Rapid Prototyping (RP). It is a process of organs
and objects reproduction by scanning the area to
be prototyped, usually through a computerized
tomography or magnetic resonance exams.
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4. 104 Cardoso CL, Munhoz EA de, Ribeiro ED, Souza Neto JB de, Sant’Ana E, Ferreira Júnior O.
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Recebido: 20/03/2007
Received: 03/20/2007
Aceito: 25/04/2007
Accepted: 04/25/2007
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