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jaw prosthesis

Jaw Prosthesis

Patient specific mandible implant

Customised design and development of patient specific 3D printed whole mandible implant

Mazher I. Mohammed, Angus P. Fitzpatrick, Santosh K. Malyala, Ian Gibson

In this study we assessed the design criteria for the creation of a patient specific, whole mandible implant based on a patient’s medical imaging data and 3D printing. We tailor this procedure to a patient who will undergo a mandibulectomy due to cancer infiltration of the jaw. The patient CT scan data was used to generate a 3D representation of the patient’s skull, before the corrupted mandible was extracted. We examined two approaches based on classical symmetry matching and digital reconstruction of the defect to form the final model for printing. The final designs were then 3D printed and assessed for efficacy against a patient specific representative model of the skull and maxilla, where the final optimised design was found to provide an excellent fit. Ultimately, this technique provides a framework for the design and optimisation of a patient specific whole mandible implant.

Please note:

This abstract was published on Bonash Medical’s website since its content was related to the company’s products. There is no relation between Bonash Medical and the authors. To have full access to the article, please refer to relevant reference.

Custom implants in craniofacial surgery

3D modeling, custom implants and its future perspectives in craniofacial surgery

Dr. Jayanthi Parthasarathy, Dr, Plano

Annals of Maxillofacial Surgery

Custom implants for the reconstruction of craniofacial defects have gained importance due to better performance over their generic counterparts. This is due to the precise adaptation to the region of implantation, reduced surgical times and better cosmesis. Application of 3D modeling in craniofacial surgery is changing the way surgeons are planning surgeries and graphic designers are designing custom implants. Advances in manufacturing processes and ushering of additive manufacturing for direct production of implants has eliminated the constraints of shape, size and internal structure and mechanical properties making it possible for the fabrication of implants that conform to the physical and mechanical requirements of the region of implantation. This article will review recent trends in 3D modeling and custom implants in craniofacial reconstruction.

Please note:

This abstract was published on Bonash Medical’s website since its content was related to the company’s products. There is no relation between Bonash Medical and the authors. To have full access to the article, please refer to relevant reference.

Reconstruction of maxilla

Reconstruction of maxillary and orbital floor defect with free fibula flap and whole individualized titanium mesh assisted by computer techniques.

Kun Fu, MDS, Yiming Liu, DDS, Ning Gao, MDS, Jinghua Cai, Phd, Wei He, DDS, Professor, Weiliu Qiu, DDS, Professor.

Journal of Oral and Maxillofacial Surgery

Objective: To investigate the clinical application of the free fibula flap and the individualized titanium mesh, through virtual planning and guiding template to assist the reconstruction of maxilla and orbital floor defects.

Methods: Between 2015 and 2016, a total of six adult patients with maxillary and orbital floor defects were enrolled in the study. Preoperative virtual planning, including virtual maxillary resection and fibular reconstruction, was performed in all cases according to three-dimensional (3-D) radiographic and clinical findings. A printed 3-D resin model for pre-bent templates to guide the harvesting and positioning of the fibular flap during the surgery. Then an individualized titanium mesh is used to support the orbital floor and restore the maxillary contour. The results were confirmed by postoperative CT scans and clinical follow-up.

Results: Preoperative virtual planning and pre-bent template can be used to guide the harvesting and positioning of fibular flap and the forming and positioning of the individualized titanium mesh with satisfactory results. All flaps were survived and symmetric facial contours were achieved with normal lower jaw movements and proper vertical distance for dental implants in all patients.

Conclusion: Computer-aided techniques such as virtual planning, 3D printed model and pre-bending guide template can be used for the harvesting and positioning free fibula flap, the forming personalized titanium mesh, and ultimately the improving clinical efficacy of maxillary and orbital floor reconstruction.

Please note:

This abstract was published on Bonash Medical’s website since its content was related to the company’s products. There is no relation between Bonash Medical and the authors. To have full access to the article, please refer to relevant reference.

Mandibular Reconstruction Plates

Customized Repair of Fractured Mandibular Reconstruction Plates

Zachary S. Peacock, DMD, MD,* Salim Afshar, DMD, MD

Journal of Oral Maxillofacial Surgery

Purpose: To describe a novel technique using custom prostheses to repair fractured mandibular reconstruction plates spanning discontinuity defects.

Materials and Methods: This is a retrospective case series reviewing the design, rapid manufacture, and use of a novel method to repair fractured plates. Three patients who could not undergo autogenous bone grafting procedures or replacement of the entire plate for medical or socioeconomic factors were treated by this method.

Results: Three patients with fractured reconstruction plates were treated with a custom prosthesis engaging the reconstruction plate. Continuity and function were restored with a minimally invasive operation and short hospital stay. The custom prosthesis remained in place with stable occlusion in all 3 patients at a minimum of 9 months’ follow-up.

Conclusions: A technique using a custom prosthesis to quickly and less invasively restore continuity and function of the mandible after fracture of a reconstruction plate.

Please note:

This abstract was published on Bonash Medical’s website since its content was related to the company’s products. There is no relation between Bonash Medical and the authors. To have full access to the article, please refer to relevant reference.

Craniomaxillofacial surgery

Customized titanium implant fabricated in additive manufacturing for craniomaxillofacial surgery

André Luiz Jardini, Maria Aparecida Larosa, Cecília Amélia de Carvalho Zavaglia, Luis Fernando Bernardes, Carlos Salles Lambert, Paulo Kharmandayan, Davi Calderoni & Rubens Maciel Filho

Virtual and Physical Prototyping

Customised implants manufacture has always presented difficulties which result in high cost and complex fabrication, mainly due to patients’ anatomical differences. The solution has been to produce prostheses with different sizes and use the one that best suits each patient. Additive manufacturing (AM) as a technology from engineering has been providing several advancements in the medical field, particularly as far as fabrication of implants is concerned in craniomaxillofacial surgery. The use of additive manufacturing in medicine has added, in an era of development of so many new technologies, the possibility of performing the surgical planning and simulation by using a threedimensional (3D) physical model, very faithful to the patient’s anatomy.

AM is a technology that enables the production of models and implants directly from the 3D virtual model (obtained by a Computer-Aided Design (CAD) system, computed tomography or magnetic resonance) facilitating surgical procedures and reducing risks. Furthermore, additive manufacturing has been used to produce implants especially designed for a particular patient, with sizes, shapes and mechanical properties optimised, for areas of medicine such as craniomaxillofacial surgery. This work presents how AM technologies were applied to design and fabricate a biomodel and customised implant for the surgical reconstruction of a large cranial defect. A series of computed tomography data was obtained and software was used to extract the cranial geometry. The protocol presented was used for creation of an anatomic biomodel of the bone defect for the surgical planning and, finally, the design and manufacture of the patient-specific implant.

Please note:

This abstract was published on Bonash Medical’s website since its content was related to the company’s products. There is no relation between Bonash Medical and the authors. To have full access to the article, please refer to relevant reference.

Custom made cranioplasty

Custom made titanium cranioplasty early and late complications of 151 cranioplasties and review of the literature.

R. Williams, K. F. Fan, R. P. Bentley

Int. J. Oral Maxillofac. Surg.

A diverse range of techniques is available for reconstruction of full-thickness calvarial defects and the optimum substrate for cranioplasty remains unproven. During a 9-year period, 149 patients underwent insertion of 151 custom-made titanium cranioplasties using the same technique. Data relating to patient demographics, indication for cranioplasty, and site and size of the defect were collected from the clinical records. Patients were followed up in all cases for a mean of 1 year 2 months (range 7 days to 8 years 8 months). Early complications requiring intervention were experienced in 7% and included seroma, haematoma, and continued bleeding necessitating implant removal in one patient.

One death occurred at 3 days’ post-operation due to haemorrhagic stroke. Late self-limiting complications such as seroma were experienced in 19% of patients, however complete failure requiring implant removal was seen in only 4% of cases. Infection was the cause of failure in all cases. A comprehensive literature review was carried out and data abstracted to compare reported failure rates in other techniques of full-thickness cranial reconstruction. This review shows that custom-made patient specific titanium cranioplasties compare very favorably to the other published techniques and remain a tried and tested option for reconstruction of all sizes of full-thickness calvarial defect.

Please note:

This abstract was published on Bonash Medical’s website since its content was related to the company’s products. There is no relation between Bonash Medical and the authors. To have full access to the article, please refer to relevant reference.

Maxillary & mandibular defects

Surgical reconstruction of maxillary & mandibular defects using a printed titanium mesh

Xiao-Feng Shan, DDS, MD, Associate Professor, Hui-Min Chen, DDS, MD, Attending Physician, Jie Liang, DDS, Resident, Jin-Wei Huang, DDS, Resident, Zhi-Gang Cai, DDS, DMD, Professor

Journal of Oral and Maxillofacial Surgery.

Purpose: Reconstruction of maxillary & mandibular defects with a printed titanium mesh using computer-assisted surgery (CAS) for the achievement of structural, esthetic, and functional goals. Methods: The investigators designed and implemented this prospective study comprising patients with maxillary or mandibular flaws who underwent reconstruction with a printed titanium mesh using CAS. After surgery, the preoperative design and postoperative outcome were evaluated using Geomagic Studio software. Results: The sample comprised two patients with maxillary defects and two with mandibular defects. A satisfactory contour was achieved in all patients. The rate of concordance between the preoperative design and postoperative outcome was more than 81 and 94% within 3 mm for the mandibular and maxillary reconstructions, respectively. Conclusion: The results of this study suggest that complicated maxillary and mandibular flaws can be satisfactorily reconstructed with customized printed titanium meshes using CAS. Please note: This abstract was published on Bonash Medical’s website since its content was related to the company’s products. There is no relation between Bonash Medical and the authors. To have full access to the article, please refer to relevant reference.

Patient specific orbital implant

Patient specific implants (PSI) in reconstruction of orbital floor and wall fractures

Thomas Gander a, *, Harald Essig a, Philipp Metzler a, Daniel Lindhorst a, Leander Dubois b,

Journal of Cranio-Maxillo-Facial Surgery

Fractures of the orbital wall and floor can be challenging due to the demanding three dimensional anatomy and limited intraoperative overview. Misfitting implants and inaccurate surgical technique may lead to visual disturbance and unaesthetic results. A new approach using individually manufactured titanium implants for daily routine is presented in the current paper.  Preoperative CT-scan data were processed to generate a 3D-reconstruction of the affected orbit using the mirrored non-affected orbit as template and the extent of the patient specific implant (PSI) was outlined and three landmarks were positioned on the planned implant in order to allow easy control of the implant’s position by intraoperative navigation. Superimposition allows the comparison of the postoperative result with the preoperative planning. Neither reoperation was indicated due to malposition of the implant and the ocular bulb nor visual impairments could be assessed. PSI allows precise reconstruction of orbital fractures by using a complete digital workflow and should be considered superior to manually bent titanium mesh implants. Please note: This abstract was published on Bonash Medical’s website since its content was related to the company’s products. There is no relation between Bonash Medical and the authors. To have full access to the article, please refer to relevant reference.

Cranioplasty with Patient Specific Implants

Interval cranioplasty with patient specific implants and autogenous bone grafts – Success and cost analysis

Bernd Lethaus a, Monique Bloebaum a, David Koper a, Mariel Poort-ter Laak b, Peter Kessler

Journal of Cranio-Maxillo-Facial Surgery

Different options exist for the reconstruction of craniectomy defects following interval cranioplasty. The standard procedure is still based on the re-implantation of autogenous bone specimen which can be stored in the abdominal wall or be cryopreserved. Alternatively, patient-specific implants (PSIs) can be used. We conducted a retrospective study based on 50 consecutive patients with skull bone defects of 100 cm2 or more being operated on by the same team of surgeons. Thirty-three patients agreed to take part in the study. Seventeen patients who underwent reconstruction with PSIs (follow-up, 43 months [range, 3-93]) were compared with 16 control subjects who had autogenous bone grafts re-implanted (follow-up, 32 months [range, 5-92]). Criteria analyzed were the success and complication rates, operation time, duration of hospitalization and the treatment costs. Complication rate and the rate of reoperation were significantly lower, and the hospital stay was shorter in the PSI group. The treatment costs for reconstruction with autogenous bone were lower than skull bone reconstruction based on PSIs. Due to biological reasons some of the autogenous bone implants fail due to infection and resorption and the patients have to undergo another operation with implantation of a PSI in a secondary attempt. For those patients the highest overall treatment costs must be calculated. Conclusion: High success rates and reliability of PSIs may change the treatment strategy in patients undergoing interval cranioplasty. Please note: This abstract was published on Bonash Medical’s website since its content was related to the company’s products. There is no relation between Bonash Medical and the authors. To have full access to the article, please refer to relevant reference.