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COPY RISTO KONTIO AND JUKKA KANERVA IMAGES HELSINKI UNIVERSITY HOSPITAL CASE STUDY
Outstanding results with
Planmeca’s patient-specific titanium
implants and autoclavable guides
Pre-surgery situation Implant fits perfectly Post-operative CT
A81 year old female patient was referred 3D virtual implant 29
to Helsinki University Hospital, Dept.
of Oral and Maxillofacial Surgery. Her main the surgical procedure and to design patient- Operation time reduced
complaint was a growing pain in the left side specific implant and Planmeca ProModel
of her lower jaw. She had suffered from pain autoclavable guides for proper and accurate During the operation no difficulties were
for two to three months. Her general health resection of the mandible. encountered. Using the extraoral approach
was not good. the mandible was resected and the tumour
A 3D-CAD model, based on CT, was removed. The guides were used to guide
During the clinical examination, a large created in Planmeca. Free margins of 1.5 the resection through exactly in the similar
tumour was observed in the left mandibular cm were measured and marked onto the manner as the virtual CAD surgery. Neither
gingiva. A partially edentulous upper and 3D model. Using CAD the resection lines tracheostomy nor neck dissection was
lower jaw was observed and the remaining were drawn and virtual bone resection was necessary. The Planmeca ProModel patient-
teeth in the lower jaw were from first premolar carried out. The second step was to create specific reconstruction plate fitted perfectly
left to first premolar right. The sensation of autoclavable guides to be able to conduct the into the resection area. Finally the soft tissue
left lower lip was normal, indicating no injury clinical resection procedure exactly in the defect was covered from the intraoral side
of mandible and / or mental nerve. similar manner as the virtual operation. using microvascular radial fore arm flap.
CT examination revealed a 2 cm x 3 cm Finally, the individually-contoured recon "The operation lasted only 4 hours 30
tumour tissue, which was invading tooth struction plate was designed in Planmeca. minutes, because of the exact plan and
bearing process of the left mandible. No signs Because of t he one-off nature, the patient- preoperatively manufactured implants," said
of metastatic lymph nodes were detected. A specific reconstruction plate does not need surgeon Risto Kontio of Helsinki University
tissue sample was taken showing the tumour to resemble standard reconstruction plates. Hospital.
to be a moderately differentiated squamous
cell carcinoma. The primary CT was taken on 30 August Patient stayed in the intensive care unit for
and the operation was performed 4 weeks one day and was discharged from the hospital
The decision of operative treatment to later. Meanwhile, a biopsy was taken, patient’s on the 14th postoperative day.
remove the malignant tumour was made. general health thoroughly investigated, and
Due to invasion to mandible, en bloc surgery and anaesthesia plans concluded.
mandible resection was mandatory. Because
of the inferior general health of the patient Also, the Planmeca ProModel guides and
any composite flap reconstruction was not patient-specific reconstruction plate were
possible. The conclusion was that mandible prepared.
defect should be reconstructed using patient-
specific titanium reconstruction plate. The
length of operation also had to be minimized
because of the poor general health of the
patient.
Preoperative 3D planning
The virtual operation was carried out
using Planmeca ProModel and individual
3D-CAD technique in order to plan and test
