The new method of manufacturing individual mandibular prostheses, in combination with CT data and CNC technique, can duplicate bone tissues accurately, and can have the individual mandibular prosthesis made to order, and repair the mandibular defect (especially the lager mandibular segmental defect).
Computer-Aided Design ; Imaging, Three-Dimensional ; Mandible ; diagnostic imaging ; Mandibular Prosthesis ; Mandibular Prosthesis Implantation ; Prosthesis Design ; Tomography, X-Ray Computed ; methods

OBJECTIVETo evaluate the feasibility of designing and fabricating customized titanium bone substitutes to restore mandibular bone defects using reverse engineering (RE) and rapid prototyping (RP) techniques.

METHODSTitanium tray for mandibular defects were designed and fabricated through multi-step procedures of reverse engineering and rapid prototyping, then in operation it was filled with cancellous bone and fixed.

RESULTSThe bone substitutes fabricated by this method had been successfully put into clinical use for maxillofacial surgery in 2 patients and got a satisfactory result.

CONCLUSIONSReverse engineering combining with rapid prototyping could accomplish the design and manufacture of implant for the restoration of mandibular bone defects.

Adult ; Biomedical Engineering ; Bone Substitutes ; Female ; Humans ; Male ; Mandible ; surgery ; Mandibular Prosthesis Implantation ; methods

OBJECTIVETo investigate the application of computer aided design-computer aided manufacture (CAD-CAM) technique in the reconstruction of mandible defect with individual titanium prosthesis.

METHODSSix patients with large mandibular ramus and angle tumor were spiral CT scanned preoperatively, and the CAD-CAM was used to design and make individual titanium prosthesis for reconstructing the mandibular defects after resection of the tumor. The prosthesis were assembled during operation. Postoperative follow-up period was 9 - 38 months.

RESULTSThe design and manufacture of titanium prosthesis by use of CAD-CAM technique was convenient and the prosthesis fitted the defects very well. The outline of the face, the occlusion and function were restored. After 9 - 38 months of follow-up, the mandibular symmetry was good.

CONCLUSIONSThe application of CAD-CAM provided accurate simulation and fast manufacturing process for the titanium prosthesis in the repair of mandibular defect.

Adult ; Ameloblastoma ; rehabilitation ; surgery ; Computer Simulation ; Computer-Aided Design ; Female ; Follow-Up Studies ; Humans ; Male ; Mandible ; surgery ; Mandibular Neoplasms ; rehabilitation ; surgery ; Mandibular Prosthesis Implantation ; Mandibular Reconstruction ; Middle Aged ; Prosthesis Design ; Titanium ; Tomography, Spiral Computed ; Young Adult

The application principle and procedure of reverse engineering and rapid prototyping techniques are introduced in this paper. The description is concentrated on the applications of the above techniques in medical field, especially in reconstructive surgery of mandibular bone defect.
Biomedical Engineering ; Bone Substitutes ; Computer Simulation ; Computer-Aided Design ; Humans ; Mandible ; surgery ; Mandibular Prosthesis Implantation ; methods ; Reconstructive Surgical Procedures ; methods

Mandibular defects lead to severe deformation and functional deficiency. Vascularized osteocutaneous tissue has been widely used to reconstruct the mandible. However, it is technically challenging to shape this type of grafts in such a manner that they resemble the configuration of the mandible. A 48-year-old female patient who underwent anterolateral thigh (ALT) flap coverage after a tongue cancer excision was diagnosed with a tumor recurrence during the follow-up. A wide excision mandibulectomy and mandibular reconstruction with an ALT flap and a titanium implant were performed. The prefabricated titanium implant was fixed to the condyle. Then, an ALT flap was harvested from the ipsilateral thigh and anastomosed. After confirming that the circulation of the flap was intact, the implant was fixed to the parasymphysis. On the radiograph taken after the surgery, the prosthesis was well positioned and overall facial shape was acceptable. There was no postoperative complication during the follow-up period, 1 year and 2 months. The prefabricated implant allows the restoration of facial symmetry without harvesting autologous bone and it is a safe and effective surgical option for mandibular reconstruction.
Female ; Follow-Up Studies ; Humans ; Mandible ; Mandibular Prosthesis Implantation ; Mandibular Reconstruction* ; Middle Aged ; Postoperative Complications ; Prostheses and Implants ; Recurrence ; Thigh ; Titanium* ; Tongue Neoplasms ; Transplants

Microgenia is that the mental protuberance is small state because of symphysis did not developed properly while occlusion and size of mandible are normal. One or two-step sliding advancement genioplasty is mainly performed to make good aesthetic harmony with face, but in slight or moderate degree of microgenia patients who do not want general anesthesia or osteotomy, the multiporous high-density polyethylene(Medpor(R)) can be used. It is easy to carve and bend, and has a variety of size and shape to fit the contour of the chin anatomy. Under the local anesthesia. a vertical incision which can preserve mentalis muscle is made about 2 cm at inferior labial sulcus along inferior frenulum in the jaw midline. Subperiosteal dissection is performed to make a pocket. Seperated Medpor(R)s are inserted in each side and reassembled into one in the midline. To minimize bone erosion, implant has to be placed on the inferior side of mandible edge and fixed with screw. Bandage compression was applied for 3 days and antibiotics was treated for 7 days postoperatively. This technique has a small incision, easy procedure and faster recovery. During the follow-up period, there were no specific complications and patients were all satisfied to their result.
Anesthesia, General ; Anesthesia, Local ; Anti-Bacterial Agents ; Bandages ; Chin ; Follow-Up Studies ; Genioplasty ; Humans ; Jaw ; Mandible ; Mandibular Prosthesis Implantation ; Muscles ; Osteotomy ; Polyethylene

OBJECTIVETo study the applications of bone grafts from the cranium or mandible in the repair of posttraumatic deformities of the nose.

METHODSFrom 1997 to 2002, a total of 44 patients, who presented with secondary nose deformity as well as facial fractures, were reconstructed by autogeneous outer table grafts of the calvarial or mandibular bone after facial skeleton reposition. In this series, 32 cases used the calvarial bone, 12 cases used the mandible bone, which was harvested through a coronal incision and an oral approach respectively.

RESULTSThe surgical incisions healed primarily in all patients with minimal scar. The facial appearance was greatly improved. No implant infection, extrusion and shift were observed in the postoperative follow-up of 6 months to 2 years. There was not obvious bone resorption, nor donor site morbidity.

CONCLUSIONAutogeneous calvarial and mandibular bone was an ideal material of bone graft in reconstruction of severe posttraumatic deformities of the nose. Compared with other autogeneous and alloplastic materials, the outer table of the calvarial and mandibular bone produced less morbidity of the donor site, invisible scar, no rejection and less resorption.

Adolescent ; Adult ; Facial Injuries ; complications ; surgery ; Female ; Humans ; Male ; Mandible ; diagnostic imaging ; surgery ; Mandibular Injuries ; complications ; surgery ; Mandibular Prosthesis Implantation ; methods ; Middle Aged ; Nose ; injuries ; Patient Satisfaction ; Radiography ; Reconstructive Surgical Procedures ; methods ; Skull ; surgery ; Treatment Outcome

This study was aimed to develop a 3-D finite element (3-D FE) model of the mental fractured mandible and design the boundary constrains. The CT images from a health volunteer were used as the original information and put into ANSYS program to build a 3-D FE model. The model of the miniplate and screw which were used for the internal fixation was established by Pro/E. The boundary constrains of different muscle loadings were used to simulate the 3 functional conditions of the mandible. A 3-D FE model of mental fractured mandible under the miniplate-screw internal fixation system was constructed. And by the boundary constraints, the 3 biting conditions were simulated and the model could serve as a foundation on which to analyze the biomechanical behavior of the fractured mandible.
Adult ; Bone Plates ; Bone Screws ; Computer Simulation ; Finite Element Analysis ; Fracture Fixation, Internal ; instrumentation ; Humans ; Imaging, Three-Dimensional ; Male ; Mandible ; diagnostic imaging ; Mandibular Fractures ; surgery ; Models, Biological ; Prosthesis Design ; Prosthesis Implantation ; instrumentation ; Tomography, X-Ray Computed

In order to investigate the influence of radiation therapy after the treatment of maxillary implant-supported prostheses, 27 patients received a total of 131 implants in maxilla after oral cancer treatment and/or reconstructive surgery. Among them, 25 received maxillary implant-supported prostheses. The cumulative survival rates of implants and prostheses were evaluated by the product-limit-estimates method according to Kaplan-Meier. The cumulative survival rate of implants and prostheses in irradiated patients was compared with that in non-irradiated patients by statistical Log-rank test. The results showed that 112 implants were observed after implant loading. The implants cumulative survival rate was approximately 65% for overall patients. The cumulative prosthesis successful rate was approximately 88% for all 25 patients. Log-rank test analysis revealed that there was a significant difference in cumulative implants survival rates between non-irradiated and irradiated maxillary bone (P < 0.01). It was concluded that the implants and prostheses in irradiated patients have significantly lower survival rates than in non-irradiated patients.
Aged ; Carcinoma, Squamous Cell ; radiotherapy ; surgery ; Dental Prosthesis, Implant-Supported ; Female ; Graft Survival ; radiation effects ; Humans ; Male ; Mandibular Prosthesis ; Maxilla ; surgery ; Maxillofacial Prosthesis ; Maxillofacial Prosthesis Implantation ; Middle Aged ; Mouth Neoplasms ; radiotherapy ; surgery ; Osseointegration ; Pilot Projects ; Radiation Injuries ; Retrospective Studies ; Survival Rate ; Titanium

OBJECTIVETo evaluate the complications and factors associated with titanium plates in mandibular reconstruction with different methods.

METHODSA retrospective analysis of 660 patients who received primary reconstruction of the mandible was conducted. The characters of the mandibular defect and methods of reconstruction were recorded. The complications and factors associated with the reconstruction were analyzed.

RESULTSThe majority of mandibular defect was in a shape of L (n = 324 ). The total complication rate was 14.7% (97/660), which included screw loosening 5.8% (38/660), plate fracture 3.3% (22/660), plate exposure 3.8% (25/660), infection 7.4% (49/660) and malunion or ununion 2.9% (19/660). The mandibular defects reconstructed by reconstructive plates had a higher complication rate than that by bone grafts. The complication rate was 10.8% (63/586) in cases reconstructed by bone grafts with miniplates. The complications were associated with radiation therapy and diabetes. Radiation therapy had a significant effect on plate exposure.

CONCLUSIONSReconstruction with bone grafts can minimize the rate of plate related complication. The complications were associated with radiation therapy and diabetes.

Adult ; Ameloblastoma ; radiotherapy ; rehabilitation ; surgery ; Bone Plates ; adverse effects ; Bone Screws ; adverse effects ; Bone Transplantation ; Carcinoma, Squamous Cell ; radiotherapy ; rehabilitation ; surgery ; Female ; Follow-Up Studies ; Humans ; Male ; Mandible ; surgery ; Mandibular Neoplasms ; radiotherapy ; rehabilitation ; surgery ; Mandibular Prosthesis Implantation ; adverse effects ; Mandibular Reconstruction ; Neoplasm Recurrence, Local ; Postoperative Complications ; Retrospective Studies ; Surgical Wound Infection ; etiology ; Titanium