Technical note: maxillofacial biomodelling--preliminary result.

A new technique of manufacturing three-dimensional (3D) hard tissue biomodels is described. The models, derived from computed tomography data, were constructed by a computer-controlled manufacturing device known as stereolithography apparatus (SLA). Selected cases of patients with facial deformities were presented to illustrate clinical applications of the SLA biomodelling. Physical demonstration of the bony internal anatomy in these patients promoted better conceptualization of the disease process, allowing optimal input into the management decision, pre-operative planning and choice of surgical technique with a consequent reduction in operating time and potential reduction in peri-operative morbidity. Limitations of the solid modelling technique include cost, a lengthy production time which renders it unsuitable for emergency cases, and radiation exposure of the patient. With wider use and further technological development, these drawbacks will be minimized. The 3D SLA biomodels may in future become an adjunct, not only to maxillofacial surgery, but also to other medical specialties.

Stereolithographic biomodelling in cranio-maxillofacial surgery: a prospective trial.

Stereolithographic (SL) biomodelling is a new technology that allows three-dimensional (3-D) computed tomography (CT) data to be used to manufacture solid plastic replicas of anatomical structures (biomodels). A prospective trial with the objective of assessing the utility of biomodelling in complex surgery has been performed. Forty-five patients with craniofacial, maxillofacial, skull base cervical spinal pathology were selected. 3-D CT or MR scanning was performed and the data of interest were edited and converted into a form acceptable to the rapid prototyping technology SL. The data were used to guide a laser to selectively polymerize photosensitive resin to manufacture biomodels. The biomodels were used by surgeons for patient education, diagnosis and operative planning. An assessment protocol was used to test the hypothesis that 'biomodels in addition to standard imaging had greater utility in the surgery performed than the standard imaging alone'. Biomodels significantly improved operative planning (images 44.09%, images with biomodel 82.21%, P < .01) and diagnosis (images 65.63%, images with biomodel 95.23%, P < .01). Biomodels were found to improve measurement accuracy significantly (image measurement error 44.14%, biomodel measurement error 7.91%, P < .05). Surgeons estimated that the use of biomodels reduced operating time by a mean of 17.63% and were cost effective at a mean price of $1031 AUS. Patients found the biomodels to be helpful for informed consent (images 63.53%, biomodels 88.54%, P < .001). Biomodelling is an intuitive, user-friendly technology that facilitated diagnosis and operative planning. Biomodels allowed surgeons to rehearse procedures readily and improved communication between colleagues and patients.

Trans-antral temporalis transfer for the repair of adult cleft palates.

Temporalis muscle transfer is a versatile technique frequently used for reconstructive procedures in the maxillofacial region. However the thickness of the pedicle may interfere with masticatory function when used anteriorly in the oral cavity. To repair full-length mid-palatal defects in fully dentate patients the flap can be passed through the maxillary sinus and combined with local repair of the soft palate, thus avoiding any occlusal trauma from the posterior teeth. The operation is a single stage procedure with low morbidity and few complications, and is a useful technique for repairing the large untreated clefts frequently encountered in developing countries. The procedure is used by members of the Australian and New Zealand Association of Oral and Maxillofacial Surgeons Bangladesh Project who have operated in Dhaka teaching hospitals on a regular basis since 1991.

Maxillofacial biomodelling.

The authors report the clinical applications of biomodelling with the stereolithography apparatus, a computer-controlled manufacturing technique that builds anatomically accurate skeletal models from sectional radiological data. Reference to several individual cases demonstrates how pre-operative 3-D modelling can refine the accuracy of diagnostic information, facilitate preoperative planning and surgical technique, and reduce operating time.

Esophageal adenocarcinoma metastatic to the maxilla.

Although metastatic malignant lesions in the maxilla are exceedingly rare, case reports of such lesions do appear occasionally in the literature. This article describes the clinical and pathologic features of an esophageal adenocarcinoma metastatic to the maxilla. The initial maxillary appearance of the tumor mimicked primary dental pathosis and, in addition, was the presenting sign of malignant disease in the patient. The relevant literature is reviewed, and the processes by which metastases form are discussed.