OBJECTIVES: To investigate the clinical application of the digital-assisted reconstruction of the mandible and tumors with free fibula transplantation and immediate implantation via the intraoral approach. METHODS: Twelve patients with benign mandibular tumors were collected. Three-dimensional mandibular reconstruction was performed digitally before surgery to simulate mandibular tumor resection, fibula resection and reconstruction, and implant implantation. The intraoperative resection of the mandibular tumor was conducted through the intraoral approach under the guidance of a guide plate, and fibula resection, molding, reconstruction, and oral fixation were immediately performed. Implant implantation was performed during the second phase of implant surgery and denture restoration was performed 1-2 months after surgery. RESULTS: The types of mandibular defects were BrownⅠ (one case), Ⅰc (four cases), Ⅱ (one case), Ⅱc(three cases), and Ⅲ (three cases). The length of the fibular bone was 12-22 cm. The number of fibular molding amputations was as follows: two cases in two segments, six cases in three segments, three cases in four segments, and one case in five segments. All of these cases underwent folding fibular reconstruction of mandibular and alveolar bone defects. A total of 44 implants were implanted, and none failed after operation. CONCLUSIONS The intraoral approach is a reliable method for the resection of mandibular benign tumors, with few postoperative complications and the ability to position and fix accurately the reconstructed folded fibula under digital design. The immediate implantation of the transplanted fibula does not affect the blood supply and has a high success rate. It is an effective and reliable method for the resection and reconstruction of mandibular benign tumors.
Humans ; Fibula/transplantation* ; Mandibular Neoplasms/surgery* ; Mandibular Reconstruction/methods* ; Bone Transplantation/methods* ; Male ; Middle Aged ; Female ; Mandible/surgery* ; Adult ; Free Tissue Flaps ; Surgery, Computer-Assisted

OBJECTIVES: This retrospective study aimed to investigate factors influencing positional changes of the condyle and temporomandibular joint (TMJ) following mandibular defect reconstruction with bone flaps, and to evaluate the biomechanical impacts of flap reconstruction on condylar positioning, thereby providing evidence for optimizing surgical protocols and TMJ functional rehabilitation. METHODS: A retrospective study was conducted on 90 patients undergoing mandibular segmental resection with immediate bone flap reconstruction at Guizhou Medical University Affiliated Stomatological Hospital (June 2019 to May 2024). After strict screening, 50 cases with complete data were analyzed. Clinical parameters (defect size, location, reconstruction method) and craniofacial CT scans at four timepoints [preoperative (T0), 7-10 days (T1), 3 months (T2), and 6 months (T3) postoperatively] were collected. Mimics 20 software facilitated 3D reconstruction for measuring TMJ anterior/posterior/superior joint spaces (Kamelchuk method) and calculating condylar position via the Pullinger index [Ln (posterior/anterior space)]. Vitral and Krisjane methods quantified mandibular linear parameters (ramus length, condylar pole distances to the sagittal plane, angulation) and glenoid fossa morphology. Statistical analyses were performed using SPSS 21.0. RESULTS: Mandibular defect size and location were significant factors influencing postoperative condylar position changes (P<0.05). Compared to preoperative measurements, postoperative condylar anterior, posterior, and superior joint spaces were significantly increased (P<0.001). The most pronounced anterior condylar displacement occurred within 7-10 days postoperatively (P<0.05). In patients with condyle resection, postoperative joint space and angle changes were significant; in patients with condyle preservation, only superior and anterior joint space changes were statistically significant (P<0.05). Additionally, from T1 to T2, the changes in condylar medial-lateral distance, superior joint space, and anterior joint space were negatively correlated with the preoperative condylar position. Compared with preoperative,in the T0-T1 period, condylar medial-lateral distance, posterior joint space, and articular tubercle angle changes were significantly negatively correlated with time (P<0.05). Notably, the angle between the condylar long axis and the coronal axis showed a sustained negative trend from T1 to T3 (P<0.05). CONCLUSIONS Condylar position changes after mandibular defect repair with bone flap reconstruction are associated with the size and location of the defect. Additionally, adaptive remodeling of the temporomandibular joint (TMJ) joint space occurs postoperatively. The phenomenon of anterior displacement of the condyle in the early postoperative period (7-10 days) shows a trend of reduction with prolonged follow-up time, and further sample size research is needed.
Humans ; Retrospective Studies ; Temporomandibular Joint/surgery* ; Mandibular Condyle/surgery* ; Male ; Female ; Adult ; Middle Aged ; Mandibular Reconstruction/methods* ; Mandible/surgery* ; Surgical Flaps ; Tomography, X-Ray Computed ; Young Adult ; Biomechanical Phenomena ; Aged ; Adolescent ; Imaging, Three-Dimensional

OBJECTIVE: To propose a new protocol for personalized mandibular reconstruction assisted by three-dimensional (3D) retrieval model based on fully connected neural network (FCNN) and a database of mandibles, and to verify clinical feasibility of the protocol. METHODS: A database of mandibles of 300 normal northern Chinese Han people was established. On the basis of cephalometry, the mandible landmarks with good stability were further screened. Mandibular landmarks were selected and geometric features of the mandible were extracted. A 3D retrieval algorithm was developed, which could retrieve the mandible most similar to a given mandible from the database. A FCNN was built to train the algorithm to improve accuracy of the 3D retrieval model. Using Geomagic Control 2014 software, matching accuracy of the 3D retrieval model was based on aforementioned mandible database and algorithm. From December 2019 to March 2021, a total of 5 patients underwent personalized mandibular reconstruction assisted by a 3D retrieval model based on mandible database and FCNN in the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology. The most similar mandible was retrieved from mandible database through 3D retrieval algorithm. It was used to restore the premorbid morphology of defect area and guide mandibular reconstruction. For the 5 patients, mandible was reconstructed with iliac flap. Virtual surgical plan was transformed using individual surgical guides. RESULTS: Through screening, mandibular landmarks with high reproducibility and stability were identified and composed of mandibular landmarker protocols. After training, the average deviation between most similar mandible retrieved from the 300-case mandible database through 3D retrieval model based on FCNN and given mandible was (1.77±0.44) mm. And the root-mean-square deviation between the most similar mandible retrieved from the database and given mandible was (2.58±0.86) mm. The mandibular reconstruction surgery was successful in all the 5 patients. Their facial symmetry and occlusion were restored. All the patients were satisfied with postoperative appearance. The mean deviation between postoperative mandible and preoperative design was (0.98±0.17) mm. The area with a deviation ≤1 mm accounted for 61.34%±14. 13%, ≤2 mm accounted for 83.82%±7.35%, and ≤3 mm accounted for 93.94%± 2.87%. CONCLUSION The personalized mandibular reconstruction assisted by 3D retrieval model based on the 300-case mandible database and FCNN is feasible clinically.
Humans ; Neural Networks, Computer ; Mandibular Reconstruction/methods* ; Mandible/diagnostic imaging* ; Imaging, Three-Dimensional/methods* ; Adult ; Databases, Factual ; Female ; Male ; Algorithms ; Middle Aged ; Cephalometry

Objective:Exploring the clinical application effect of a series of digital designed guide plates in the repair of mandibular defects with free fibular muscle flap. Methods:A total of 32 patients who underwent fibular muscle flap repair of mandibular defects in the Head and Neck Tumor Surgery Department of Xi'an Jiaotong University Stomatological Hospital were selected as the research subjects. They were divided into a guide plate assisted group（16 cases） and a conventional surgery group（16 cases） according to the different surgical methods. The guide plate assisted group completed the surgery with the assistance of a digital design series of guide plates, while the conventional surgery group served as the control. Record the preparation and shaping time of two groups of fibular myocutaneous flaps, evaluate the surgical effect at least 6 months after surgery, and conduct a patient satisfaction survey. Use SPSS 16.0 software package to statistically process the data. Results:The preparation and shaping time of the fibular muscle flap in the guide plate assisted group were significantly shorter than those in the conventional surgery group（P<0.05）. The excellent and good rate（87.5%） of the guide plate assisted group in evaluating the surgical effect was significantly higher than that of the conventional surgery group（75.0%）（P<0.05）. The satisfaction scores of patients in the guide plate assisted group for facial shape and bite function recovery were significantly higher than those in the conventional surgery group（P<0.05）, while there was no significant statistical difference in the satisfaction scores of pronunciation function recovery between the two groups（P>0.05）. Conclusion:The design of digital guide plates can improve the accuracy of repairing mandibular defects with fibular flaps, shorten the preparation and shaping time of fibular flaps, restore good facial appearance and bite relationship of patients, and improve satisfaction. It is worth promoting and applying in clinical practice, but the design accuracy still needs to be continuously improved.
Humans ; Myocutaneous Flap ; Mandible/surgery* ; Fibula/transplantation* ; Plastic Surgery Procedures/methods* ; Male ; Free Tissue Flaps ; Female ; Middle Aged ; Mandibular Reconstruction/methods* ; Adult ; Patient Satisfaction

Jaw defects caused by various reasons often seriously affect appearance and function. The goal of the treatment of oral and maxillofacial tumors should include the cure of the tumor and the restoration of premorbid function. The development of microsurgery and digital surgery technology has promoted the development of jaw reconstruction with vascularized free bone flap. Good appearance and improved predictability could be obtained with the help of preope-rative visual design. How to rehabilitate occlusal function on the reconstructed jaw and improve the quality of life of patients has become an important research direction. This article discusses the challenge of jaw reconstruction, the selection of vascularized bone flap, the choice of implant timing, the treatment of peri-implant soft tissue, and the influence of radiotherapy on implants after jaw reconstruction.
Humans ; Dental Implants ; Plastic Surgery Procedures ; Free Tissue Flaps/surgery* ; Quality of Life ; Dental Implantation, Endosseous ; Fibula/surgery* ; Bone Transplantation ; Mandibular Reconstruction

At present, mandibular defect repair and reconstruction is not only a simple sense of mandibular continuity restoration, but also a restoration of the physiologically positional relationship and movement balance of the upper and lower jaws. Eventually, the implantation of osseointegrated dental implants and implant-supported dental restoration should be accomplished to complete the reconstruction of the functional mandible. The technique can integrate multiple procedures such as fibular bone grafting, simultaneous dental implants and traction osteogenesis, and the perfect integration with digital technology can significantly improve the accuracy of digital dental implant traction technique. This paper will summarize and conclude the key points of the application of digital dental implant traction technique in mandibular defect reconstruction, in order to provide new ideas for the development of digital technique.
Humans ; Mandibular Reconstruction ; Dental Implants ; Dental Implantation, Endosseous/methods* ; Mandibular Neoplasms/surgery* ; Fibula/transplantation* ; Bone Transplantation/methods* ; Mandible/surgery*

The present study investigates Mg-SiO
Magnesium ; Mandibular Reconstruction ; Materials Testing ; Nanocomposites ; Silicon Dioxide

OBJECTIVE: To investigate the position change of the fibular bone after maxillary reconstruction by free fibular flap and to analyze the factors affecting the position change. METHODS: Patients who underwent maxillary reconstruction by free fibular flap in the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology from November 2012 to November 2016 were enrolled in this study. CT scans 1 week and 1 year postoperatively were collected and stored in DICOM format. The ProPlan CMF software was used to reconstruct the CT scans and separate the maxilla and each segment of the fibular flap. The Geomagic Control software was used to measure the long axis direction vector of each fibular segment. And the position change direction was recorded. The patients were divided into groups according to the use of the fibula or titanium plate to reconstruct the zygomaticmaxillary buttress. RESULTS: A total of 32 patients were enrolled. Among them, 21 were in the titanium plate group and 11 in the fibula bone group. The angle between the long axis of the fibular segment and the X axis in the X-Y plane was 95.65°±53.49° and 95.53°±52.77°, 1 week and 1 year postoperatively, and there was no statistical difference (P>0.05). The angle between the long axis of the fibular segment and the X axis in the X-Z plane was 96.88°±69.76° and 95.33°±67.42°, respectively, with statistical difference (P=0.0497). The angular changes of the long axis of the fibular segment in the titanium plate group and the fibular bone group were 3.23°±3.93° and 1.94°±1.78°, respectively, and the angular changes in the X-Z plane were 6.02°±9.89° and 3.27°±2.31°, respectively. There was no significant difference between the groups (P>0.05). The long axis changes of the fibular segment in the X-Y plane for reconstruction of the anterior alveolar, posterior alveolar, and buttress were 3.13°±3.78°, 2.56°±3.17°, and 5.51°±4.39°, respectively. There was a statistical difference (P = 0.023) between the posterior and buttress. In the X-Z plane, theses were 4.94°±4.75°, 5.26°±10.25°, 6.69°±6.52°, respectively. There was no statistical difference among the three groups (P>0.05). The main positional deviation directions of the titanium plate group and the fibular bone group were interior and superior sides, and there was no statistical difference between the two groups (P>0.05). CONCLUSION One year postoperatively, the position of the free fibular flap was changed compared with 1 week postoperatively. The position of the free fibular flap was mainly changed to the interior and superior sides.
Bone Transplantation ; Fibula/diagnostic imaging* ; Free Tissue Flaps ; Humans ; Mandibular Reconstruction ; Maxilla/surgery*

BACKGROUND: Condylar dislocation can arise as a complication in patients who required mandibular and/or condylar reconstruction and were operated on with fibula free flap (FFF) using surgical guides designed using simulation surgery. Surgeons should be aware of the complications in these present cases when planning and performing reconstructions as well as predicting prognoses. CASES PRESENTATION: Two cases showed condylar dislocation in mandibular reconstruction using a FFF fixed with a reconstruction plate. Three cases showed condylar dislocation in mandibular reconstruction using a fibula free flap fixed with a mini-plate. CONCLUSION: Despite the lack of clinical symptoms in these cases following mandibular reconstruction using an FFF, the mandibular condyle was severely displaced away from the glenoid fossa. A surgeon must have sufficient time to consider the use of a long flap with thickness similar to that of the mandible, ways to minimize span and bending, and methods of fixation. The patient, moreover, should be educated on condylar dislocation. Customized CAD/CAM-prototyped temporomandibular condyle-connected plates may be a good alternative even if virtual simulation surgery is to be performed before surgery. These considerations may help reduce the incidence of complications after mandibular reconstruction.
Dislocations ; Fibula ; Free Tissue Flaps ; Humans ; Incidence ; Mandible ; Mandibular Condyle ; Mandibular Reconstruction ; Prognosis ; Surgeons

Ameloblastoma is a benign odontogenic epithelial tumor with high recurrence rate and requires extensive resection of the surrounding tissue and reconstruction of defect site. Because of the anatomical limitation of the reconstruction site, prosthetic treatment with implants is the first recommendation. This is a case of prosthetic restoration of the reconstruction site with implant fixed prosthesis in patient who underwent mandibular resection and iliac bone reconstruction due to ameloblastoma. However 14 months after completion of implant prosthesis, adjacent natural tooth erupted unexpectedly, resulting in 1mm infra-occlusion occurred including posterior implant prosthesis and anterior natural teeth. In adults, implant infra-occlusion may occur due to residual growth after placement of the maxillary anterior implant. But this case, hypo-occlusion of molar implant and open bite of anterior natural teeth is occurred due to extrusion of adjacent tooth, is rare. Thus we report the treatment process including orthodontic treatment with intrusion of the posterior tooth, and investigate the causes of sudden, unexpected tooth extrusion.
Adult ; Ameloblastoma ; Humans ; Mandibular Reconstruction ; Molar ; Open Bite ; Orthodontic Extrusion ; Prostheses and Implants ; Recurrence ; Tooth