Search

This clinical report presents a technique to reconstruct extensively resected mandibles using a combination of autologous bone grafts and additive manufacturing techniques. Mandibular defects, often arising from trauma, tumors, or congenital anomalies, can severely impact both function and aesthetics. Conventional reconstruction methods have their limitations, often resulting in suboptimal outcomes. In these reports, we detail clinical cases where patients with different mandibular defects underwent reconstructive surgery. In each instance, autologous grafts were harvested to ensure the restoration of native bone tissue, while advanced virtual planning techniques were employed for precise graft design and dental implant placement. The patients experienced substantial improvements in masticatory function, speech, and facial aesthetics. Utilizing autologous grafts minimized the risk of rejection and complications associated with foreign materials. The integration of virtual planning precision allowed customized solutions, reducing surgical duration and optimizing implant positioning. These 2 cases underscores the potential of combining autologous grafts with virtual planning precision and dental implants produced by additive manufacturing for mandible reconstruction. [ABSTRACT FROM AUTHOR]

Medical applications of additive manufacturing have seen a significant growth in recent years due to availability of advanced medical imaging and design software and wide range of materials. The range of additively manufactured medical implants is growing rapidly and surgeons need to keep themselves updated with state-of-the-art of the technology. This article reviews several articles related to medical implants to help surgeons and researchers to stay up-to-date on recent developments in the domain. Additively manufactured medical implants are reviewed into five categories: orthopedic implants, dental implants, cranioplasty implants, scaffold implants for tissue engineering and other medical implants including chest wall reconstructive implants, anti-migration enhanced tracheal stents, and buccopharyngeal stents. Additive manufacturing process and material for fabrication of each type of implant are highlighted in the study. It has been observed that titanium alloy is a suitable material for cementless arthroplasty. Porosity in the implants supports bone ingrowth, which results in a significant reduction in stress shielding. Additive manufacturing has a very attractive future in medical implant fabrication due to its capability to produce complex and customized implants. The AM provides freedom to researcher to explore the complex design of medical implants for better bone regeneration and improved osseointegration.

Secondary mandibular reconstruction using fibular free flaps (FFF) is a technical challenge for surgeons. Appropriate operation planning is crucial for postoperative quality control and is notably necessary for the (re-) achievement of a physiological condylar position, and the sensible expansion and shaping of the transplant. Computer-assisted planning may help to reconstruct mandibular defects in a patient-specific and precise manner. Herein, we present a newly-developed workflow for secondary mandibular reconstruction using FFF; it comprises digital planning and in-house manufacturing to perform precise secondary mandible reconstruction. This method utilizes a newly designed positioning device to ensure the precise positioning of the fibula segments in relation to each other and the mandibular stumps. The presented in-house-printed positioning device made it possible to achieve digital planning with high precision during surgery. [ABSTRACT FROM AUTHOR]

Background Fibula free flaps (FFF) are the gold standard tissue for the reconstruction of segmental mandibular defects. A comparison of miniplate (MP) and reconstruction bar (RB)-based fixation of FFFs has been previously described in a systematic review; however, long-term, single-center studies comparing the two plating methods are lacking. The authors aim to examine the complication profile between MPs and RBs at a single tertiary cancer center. We hypothesized that increased components and a lack of rigid fixation inherent to MPs would lead to higher rates of hardware exposure/failure. Methods A retrospective review was performed from a prospectively maintained database at Memorial Sloan Kettering Cancer Center. All patients who underwent FFF-based reconstruction of mandibular defects between 2015 and 2021 were included. Data on patient demographics, medical risk factors, operative indications, and chemoradiation were collected. The primary outcomes of interest were perioperative flap-related complications, long-term union rates, osteoradionecrosis (ORN), return to the operating room (OR), and hardware exposure/failure. Recipient site complications were further stratified into two groups: early (<90 days) and late (>90 days). Results In total, 96 patients met the inclusion criteria (RB = 63, MP = 33). Patients in both groups were similar with respect to age, presence of comorbidities, smoking history, and operative characteristics. The mean follow-up period was 17.24 months. In total, 60.6 and 54.0% of patients in the MP and RB cohorts received adjuvant radiation, respectively. There were no differences in rates of hardware failure overall; however, in patients with an initial complication after 90 days, MPs had significantly higher rates of hardware exposure (3 vs. 0, p = 0.046). Conclusion MPs were found to have a higher risk of exposed hardware in patients with a late initial recipient site complication. It is possible that improved fixation with highly adaptive RBs designed by computer-aided design/manufacturing technology explains these results. Future studies are needed to assess the effects of rigid mandibular fixation on patient-reported outcome measures in this unique population. [ABSTRACT FROM AUTHOR]

Medical applications of additive manufacturing have seen a significant growth in recent years due to availability of advanced medical imaging and design software and wide range of materials. The range of additively manufactured medical implants is growing rapidly and surgeons need to keep themselves updated with state-of-the-art of the technology. This article reviews several articles related to medical implants to help surgeons and researchers to stay up-to-date on recent developments in the domain. Additively manufactured medical implants are reviewed in five categories: orthopedic implants, dental implants, cranioplasty implants, scaffold implants for tissue engineering and other medical implants including chest wall reconstructive implants, anti-migration enhanced tracheal stents, and buccopharyngeal stents. The additive manufacturing process and the material for fabrication of each type of implant are highlighted in the study. It has been observed that titanium alloy is a suitable material for cementless arthroplasty. Porosity in the implants supports bone ingrowth, which results in a significant reduction in stress shielding. Additive manufacturing has a very attractive future in medical implant fabrication due to its capability to produce complex and customized implants. The AM provides freedom to researcher to explore the complex design of medical implants for better bone regeneration and improved osseointegration. [ABSTRACT FROM AUTHOR]

Though the gold standard method for mandible reconstruction of the defect from segmental mandibulectomy is by osseous flap or graft, using reconstruction plates is still indicated in some cases. Traditionally, the plate is bended immediately after the segmental mandibulectomy by freehand. However, it's difficult to fit well to the original position of mandible, which may result in more complications. This study therefore aimed to investigate whether using prebent plates on computer-aided 3D printing models could reduce the complication rate. Patients who received mandible reconstruction by reconstruction plate from 2018 to 2022 were enrolled and evaluated in this study. The data, including demographics, indications for surgery, pre-existed preoperative and postoperative therapies, classification of defects, and postoperative outcomes were collected and analyzed. A total of 52 patients were enrolled in our study. The prebent group exhibited a significantly lower complication rate than that of the immediately bent group (P = 0.012). Other risk factors of plate complications included postoperative adjuvant radiotherapy (P = 0.017) and previous surgery (P = 0.047). The complication-free survival rate was also better in the prebent group in a 3-year follow-up period (P = 0.012). Prebent plates on computer-aided printing models proved to be an effective approach to reduce the complications for mandibular reconstruction in segmental mandibulectomy. [ABSTRACT FROM AUTHOR]

The posterior airway space (PAS) is a common site of passive obstructions with high morbidity. Surgical changes to the craniomandibular system may affect the PAS. Data regarding the effects of mandibular reconstruction using vascularized bone flaps on PAS are insufficient. This retrospective cohort study aimed to investigate changes in PAS after mandibular reconstruction. Pre- and post-reconstructive computed tomography scans of 40 patients undergoing segmental mandibulectomy and mandibular reconstruction with deep circumflex iliac artery or fibula flaps were analyzed. Absolute differences in PAS geometry and relative trends of PAS volume changes were compared within the study population and between subgroups formed according to the extent of resection, timing and type of reconstruction, and presence of pre-reconstructive radiotherapy. Irradiated patients were characterized by an increase in PAS volume after reconstruction. Absolute differences in total PAS volume after reconstruction were significantly different (p = 0.024) compared to non-irradiated patients. Reconstruction of central mandible segments resulted in decrease of the cross-sectional PAS areas. Absolute differences in middle cross-sectional PAS area after reconstruction were significantly different (p = 0.039) compared to non-central reconstructions. Patients who received radiotherapy were less likely to show a total PAS volume reduction after reconstruction (OR: 0.147; p = 0.007), with values adjusted for gender, age, body mass index, timing and type of reconstruction, and transplant length. Mandibular reconstruction causes changes in PAS geometry. Specifically, reconstructions of central mandibular segments can lead to a reduction in the cross-sectional areas of PAS, and mandibular reconstructions in irradiated sites may cause an increase in PAS volume. [ABSTRACT FROM AUTHOR]

Objective: This study aims to highlight the versatility of the subscapular system free flaps in head and neck reconstruction within a Veteran population. Methods: We describe a case series of patients (n = 8) from the Michael E. DeBakey Veterans Affairs Medical Center, Houston, TX between 2019 and 2021. Patient demographics, comorbidities, surgical variables, complications, flap outcomes and post-operative imaging were gathered from the electronic medical record. Results: Six patients underwent mandibular reconstruction using horizontally oriented bony scapular flaps with variable soft tissue components. One patient underwent composite maxillary and oral cavity reconstruction using a chimeric scapular tip and myocutaneous latissimus dorsi free flap. Finally, we report a successful application of a chimeric scapular tip free flap for cranioplasty in the setting of a chronically infected wound secondary to osteoradionecrosis, which has not previously been reported. All flaps survived without compromise and no donor site complications were reported postoperatively. Conclusion: The subscapular system provides highly robust and versatile tissue for complex head and neck reconstruction. Multiple bony and soft tissue components provide options to construct chimeric flaps with unparalleled spatial mobility. Creative designs used to reconstruct mandibular, maxillary, and now calvarial defects represent an expanding role of the subscapular system as a reliable option for complex head and neck reconstruction in a highly co-morbid Veteran population.

Background/purpose: With the development of computer-assisted surgery, digital guide plate was widely used in vascularized bone flap grafts for mandibular reconstruction. The purpose of this study was to design and manufacture a digital guide plate with drill-hole sharing for mandibular reconstruction and assess for surgical accuracy. Materials and methods: 17 patients that required mandibular reconstruction using fibula free flap or iliac crest free flap were included in the study. The computed tomography (CT) data of the patient's mandible and pelvis or fibula were acquired preoperatively. A surgical simulation was then performed using computer-aided surgical simulation (CASS) technology based on above date, which allowed the design of two cutting guide and a repositioning guide for mandibular reconstruction. After surgery, the accuracy of reconstruction was evaluated by superimposing the postoperative image onto the preoperative image of mandible, recording the linear and angular deviation of landmarks, measuring the differences between the planned and actual outcomes. Results: The osteotomy and repositioning of fibula or iliac crest segments were successfully performed as planned using surgical guides. The digital guide plate with drill-hole sharing showed excellent accuracy, When the iliac crest or the fibula free flap were used for mandibular reconstruction, the largest mean differences between the preoperative and postoperative were 1.11 mm and 2.8° or 1.3 mm and 3.87°. Conclusion: The digital guide plate with drill-hole sharing designed preoperatively provides a reliable method of for the mandibular reconstruction. This can assist surgeons in accurately performing osteotomy and repositioning fibula or iliac crest segments during the mandibular reconstruction.

Abstract Background Implant-supported dentures have become an essential means of restoring occlusal function after jaw reconstruction. Bone mineral density (BMD) may influence the success rate of implant denture restorations. This study aimed to explore whether the Hounsfield unit (HU) value can be used to monitor the changing trend of fibular BMD after jaw reconstruction. Results A total of 54 patients who underwent maxillar/mandibular reconstruction with a fibula flap were included in this study. There was a significant correlation between the HU value and BMD at 1 week, 3 months, and 6 months after surgery, and both were significantly correlated with follow-up time. The difference between each pair of absorption rates (DAR) was less than 10% in 66.7% and 75.9% of patients at 3 and 6 months; however, the DAR was more than 20% in 12% and 13.8% of patients at 3 and 6 months, respectively. Conclusions There is a significant correlation between HU value and BMD. The HU value can be used to roughly reflect the fibular BMD changing trend in a group of patients as opposed to an individual, and the HU value is not equivalent to BMD. Trial registration ChiCTR, ChiCTR2300069661, retrospectively registered on 22 March 2023. Retrospectively registered, https://www.chictr.org.cn/showproj.html?proj=188953 .

The aim of this study is to present a sequential strategy of soft-tissue, non-osteogenic distraction with a novel device, followed by microvascular bony reconstruction for severe cases of mandibular hypoplasia. The case of a 21-year-old woman with Goldenhar syndrome is presented, whose mandible remained severely hypoplastic despite previous attempts at distraction and was not suitable for further osteogenic distraction. Soft tissue deficiency and pin track scarring prevented free fibular transfers. A personalized distractor, anchored to the cranium and the mandibular symphysis, was designed to expand the soft tissues while allowing for physiological temporomandibular joint (TMJ) movement without compression forces. Internal distractors were placed along the osteotomies to prevent condylar luxation. After completion of the soft tissue distraction, the native mandible was resected except for the condyles and reconstructed with two free fibula flaps. This report represents the proof of concept of a sequential approach to severe lower face soft-tissue and bone deficiency, which preserves TMJ function and avoids the transfer of poorly matched skin to the face. [ABSTRACT FROM AUTHOR]

This clinical report presents a technique to reconstruct extensively resected mandibles using a combination of autologous bone grafts and additive manufacturing techniques. Mandibular defects, often arising from trauma, tumors, or congenital anomalies, can severely impact both function and aesthetics. Conventional reconstruction methods have their limitations, often resulting in suboptimal outcomes. In these reports, we detail clinical cases where patients with different mandibular defects underwent reconstructive surgery. In each instance, autologous grafts were harvested to ensure the restoration of native bone tissue, while advanced virtual planning techniques were employed for precise graft design and dental implant placement. The patients experienced substantial improvements in masticatory function, speech, and facial aesthetics. Utilizing autologous grafts minimized the risk of rejection and complications associated with foreign materials. The integration of virtual planning precision allowed customized solutions, reducing surgical duration and optimizing implant positioning. These 2 cases underscores the potential of combining autologous grafts with virtual planning precision and dental implants produced by additive manufacturing for mandible reconstruction.

With the development of computer-assisted surgery, digital guide plate was widely used in vascularized bone flap grafts for mandibular reconstruction. The purpose of this study was to design and manufacture a digital guide plate with drill-hole sharing for mandibular reconstruction and assess for surgical accuracy. 17 patients that required mandibular reconstruction using fibula free flap or iliac crest free flap were included in the study. The computed tomography (CT) data of the patient's mandible and pelvis or fibula were acquired preoperatively. A surgical simulation was then performed using computer-aided surgical simulation (CASS) technology based on above date, which allowed the design of two cutting guide and a repositioning guide for mandibular reconstruction. After surgery, the accuracy of reconstruction was evaluated by superimposing the postoperative image onto the preoperative image of mandible, recording the linear and angular deviation of landmarks, measuring the differences between the planned and actual outcomes. The osteotomy and repositioning of fibula or iliac crest segments were successfully performed as planned using surgical guides. The digital guide plate with drill-hole sharing showed excellent accuracy, When the iliac crest or the fibula free flap were used for mandibular reconstruction, the largest mean differences between the preoperative and postoperative were 1.11 mm and 2.8° or 1.3 mm and 3.87°. The digital guide plate with drill-hole sharing designed preoperatively provides a reliable method of for the mandibular reconstruction. This can assist surgeons in accurately performing osteotomy and repositioning fibula or iliac crest segments during the mandibular reconstruction. Abstract. [ABSTRACT FROM AUTHOR]

Background: Reconstruction of continuity defects following osteonecrosis in multimorbid patients is challenging. In all cases of the predescribed palliative treatment method for alloplastic mandible reconstruction, plate fractures were detected in follow‐up. We hypothesized that a modification could avoid these fractures, leading to stable long‐term results. Methods: This retrospective study compares the original method with a modification using single, laser‐sintered CAD–CAM plates instead of manually bent miniplates. The predescribed shuttering technique was used to reconstruct the mandible in its original shape with bone cement. Results: Uneventful wound healing was observed in 86% of the cases after modification of the method. No implant or plate fracture occurred. Conclusions: The presented method should be considered as a treatment option for mandible reconstruction in elderly, multimorbid patients in palliative situations. The results of this study suggest that the modification of the method leads to significantly improved long‐term stability. Donor site morbidity is avoided with this method of palliative surgery. [ABSTRACT FROM AUTHOR]

Background: Implant-supported dentures have become an essential means of restoring occlusal function after jaw reconstruction. Bone mineral density (BMD) may influence the success rate of implant denture restorations. This study aimed to explore whether the Hounsfield unit (HU) value can be used to monitor the changing trend of fibular BMD after jaw reconstruction. Results: A total of 54 patients who underwent maxillar/mandibular reconstruction with a fibula flap were included in this study. There was a significant correlation between the HU value and BMD at 1 week, 3 months, and 6 months after surgery, and both were significantly correlated with follow-up time. The difference between each pair of absorption rates (DAR) was less than 10% in 66.7% and 75.9% of patients at 3 and 6 months; however, the DAR was more than 20% in 12% and 13.8% of patients at 3 and 6 months, respectively. Conclusions: There is a significant correlation between HU value and BMD. The HU value can be used to roughly reflect the fibular BMD changing trend in a group of patients as opposed to an individual, and the HU value is not equivalent to BMD. Trial registration: ChiCTR, ChiCTR2300069661, retrospectively registered on 22 March 2023. Retrospectively registered, https://www.chictr.org.cn/showproj.html?proj=188953. [ABSTRACT FROM AUTHOR]

As the fibula free flap became the gold standard in mandibular reconstruction that required both hard tissue and soft tissue, various methods have been sought to solve the height discrepancy between the mandible and fibula. The purpose of this paper was to propose a surgical option that combined the microvascular fibula free flap with a 3D-bioprinted, patient-specific polycaprolactone (PCL) implant as a safe and simple novel method that achieved the best functional and aesthetic results in mandibular reconstruction surgery for young patients with malignant tumors. The patient's reconstructed mandible maintained volume symmetry without any deformation or complications for over 6 years. Computer-aided design/computer-aided manufacturing (CAD/CAM) and 3D printing technology enabled accurate and safe surgical results. [ABSTRACT FROM AUTHOR]

Abstract Background Computer Assisted Design and Computer Assisted Manufacturing (CAD/CAM) have revolutionized oncologic surgery of the head and neck. A multitude of benefits of this technique has been described, but there are only few reports of donor site comorbidity following CAD/CAM surgery. Methods This study investigated comorbidity of the hip following deep circumflex iliac artery (DCIA) graft raising using CAD/CAM techniques. A cross-sectional examination was performed to determine range of motion, muscle strength and nerve disturbances. Furthermore, correlations between graft volume and skin incision length with postoperative donor site morbidity were assessed using Spearman's rank correlation, linear regression and analysis of variance (ANOVA). Results Fifteen patients with a mean graft volume of 21.2 ± 5.7 cm3 and a mean incision length of 228.0 ± 30.0 mm were included. Patients reported of noticeable physical limitations in daily life activities (12.3 ± 11.9 weeks) and athletic activities (38.4 ± 40.0 weeks in mean) following surgery. Graft volume significantly correlated with the duration of the use of walking aids (R = 0.57; p = 0.033) and impairment in daily life activities (R = 0.65; p = 0.012). The length of the scar of the donor-site showed a statistically significant association with postoperative iliohypogastric nerve deficits (F = 4.4, p = 0.037). Patients with anaesthaesia of a peripheral cutaneous nerve had a larger mean scar length (280 ± 30.0 mm) than subjects with hypaesthesia (245 ± 10.1 mm) or no complaints (216 ± 27.7 mm). Conclusions Despite sophisticated planning options in modern CAD/CAM surgery, comorbidity of the donor site following iliac graft harvesting is still a problem. This study is the first to investigate comorbidity after DCIA graft raising in a patient group treated exclusively with CAD/CAM techniques. The results indicate that a minimal invasive approach in terms of small graft volumes and small skin incisions could help to reduce postoperative symptomatology. Trial registration Retrospectively registered at the German Clinical Trials Register (DRKS-ID: DRKS00029066); registration date: 23/05/2022

Reconstruction of defects of the jaws is mainly performed via free fibula flap. An incidence of 2–21% of overall flap failure is still described. We investigated the roles of volume, length and number of fibula flap segments on flap survival using novel three-dimensional segmentation tools. We also analyzed the role of other possible risk factors. Seventy-one consecutive patients with a follow up of at least three months and who underwent free fibula flap reconstruction in a single center between 2002 and 2022 have been evaluated. A total of 166 fibula segments were analyzed. Malignancies were the main reason of resection (45.1%). In 69% of the cases a reconstruction of the mandible was performed. The flaps were mainly divided in two segments (39%) (range 1–4), with a mean length of 2.52 cm and a mean volume was 3.37 cm3. Total flap failure (TFF) occurred in 12 cases, (16.9%), while partial flap failure (PFF) appeared in 3 patients (4.2%). Volume, length and number of fibula flap segments did not seem to influence flap failure incidence in uni- and multivariate analysis. Reconstruction of the maxilla and use of a recipient vessel different from the facial artery seemed to significantly impact on flap failure. Smoking and previous surgeries showed a higher trend to flap failure, but they did not reach statistical significance. Prospective and multicentric analysis on a wider population should be assessed. [ABSTRACT FROM AUTHOR]

ObjectivesCutting-edge patient-specific surgical plates (PSSPs) are supposed to improve the efficiency, precision, and functional outcomes of mandibular reconstruction. This study characterized the premium role of PSSPs in precise surgery and explored their working principles in computer-assisted mandibular reconstruction (CAMR).MethodsThe PSSPs-enhanced surgical precision was investigated through the model surgery and representative cases. Spatial deviations of reconstruction were characterized by comparing the reconstructed mandible with the virtually designed mandible. Working principles of PSSPs were distinguished by a review of evolving surgical techniques in CAMR.ResultsIn the model surgery, spatial deviations between the virtually planned mandible and the reconstructed mandible were 1.03 ± 0.43 mm in absolute distance deviation, 1.70 ± 1.26 mm in intercondylar length, and 1.86 ± 0.91 mm in intergonial length in the study group of PSSPs, significantly smaller than in the control group of conventional prebent surgical plates. Meanwhile, in the study group, distance deviations were 0.51 ± 0.19 mm in bone-plate distance and 0.56 ± 0.28 mm in drilled screw holes, indicating the art of matching structures and holes. The PSSPs-enhanced CAMR was further demonstrated in three representative cases of mandibular reconstruction. Finally, four primary techniques of CAMR were summarized based on a review of 8,672 articles. The premium role of PSSPs was distinguished by the benefits of matching structures and holes.ConclusionsThe PSSPs-enhanced surgical precision was verified through the model surgery and demonstrated in human surgery. Compared to other surgical techniques of CAMR, PSSPs contributed to the precise surgery by the art of matching structures and holes.

Background: Computer Assisted Design and Computer Assisted Manufacturing (CAD/CAM) have revolutionized oncologic surgery of the head and neck. A multitude of benefits of this technique has been described, but there are only few reports of donor site comorbidity following CAD/CAM surgery. Methods: This study investigated comorbidity of the hip following deep circumflex iliac artery (DCIA) graft raising using CAD/CAM techniques. A cross-sectional examination was performed to determine range of motion, muscle strength and nerve disturbances. Furthermore, correlations between graft volume and skin incision length with postoperative donor site morbidity were assessed using Spearman's rank correlation, linear regression and analysis of variance (ANOVA). Results: Fifteen patients with a mean graft volume of 21.2 ± 5.7 cm3 and a mean incision length of 228.0 ± 30.0 mm were included. Patients reported of noticeable physical limitations in daily life activities (12.3 ± 11.9 weeks) and athletic activities (38.4 ± 40.0 weeks in mean) following surgery. Graft volume significantly correlated with the duration of the use of walking aids (R = 0.57; p = 0.033) and impairment in daily life activities (R = 0.65; p = 0.012). The length of the scar of the donor-site showed a statistically significant association with postoperative iliohypogastric nerve deficits (F = 4.4, p = 0.037). Patients with anaesthaesia of a peripheral cutaneous nerve had a larger mean scar length (280 ± 30.0 mm) than subjects with hypaesthesia (245 ± 10.1 mm) or no complaints (216 ± 27.7 mm). Conclusions: Despite sophisticated planning options in modern CAD/CAM surgery, comorbidity of the donor site following iliac graft harvesting is still a problem. This study is the first to investigate comorbidity after DCIA graft raising in a patient group treated exclusively with CAD/CAM techniques. The results indicate that a minimal invasive approach in terms of small graft volumes and small skin incisions could help to reduce postoperative symptomatology. Trial registration Retrospectively registered at the German Clinical Trials Register (DRKS-ID: DRKS00029066); registration date: 23/05/2022 [ABSTRACT FROM AUTHOR]

Porcine mandibular defect models are commonly used for the preclinical evaluation of reconstruction techniques. Existing studies vary in technique, complexity, and postoperative outcomes. The procedures are complex and often described without sufficient detail. We describe in detail a simple and reproducible method for creating a critical-size mandibular defect in a porcine model. Seven hemimandibular critical size defects were created in five male Yorkshire-Landrace pigs, three with unilateral defects and two with bilateral defects. A transverse incision was made over the mandibular body. Periosteum was incised and elevated to expose the mandibular body and a critical-size defect of 30 × 20 mm created using an oscillating saw. The implant was inserted and fixed with a titanium reconstruction plate and bicortical locking screws, and the wound closed in layers with resorbable sutures. Intraoral contamination was avoided. Dentition was retained and the mental nerve and its branches preserved. The marginal mandibular nerve was not encountered during dissection. All pigs retained normal masticatory function, and there were no cases of infection, wound breakdown, haematoma, salivary leak, or implant-related complications. The procedure can be performed bilaterally on both hemimandibles without affecting load-bearing function. All pigs survived until the end point of three months. Postoperative computed tomographic scans and histology showed new bone formation, and a three-point bend test showed the restoration of biomechanical strength. Straight-segment mandibulectomy is a simple and reproducible method for the creation of critical-size mandibular defects in a porcine model, simulating a load-bearing situation. [ABSTRACT FROM AUTHOR]

The fibula free flap is the standard of care in the reconstruction of large mandibular defects in pediatric patients, enabling adequate restoration of the facial contour. However, the unpredictable growth potential of the reconstructed mandible could influence the preservation of the initially restored symmetry over time. Being mindful of the importance of facial appearance during developmental stages, this study aimed to evaluate the long-term facial symmetry after mandible reconstruction using this technique in growing patients. A photogrammetric analysis of facial symmetry using the "Asymmetry Index" (AI) was performed from preoperative and postoperative frontal photographs in 17 pediatric patients (9 males and 8 females) who underwent mandibular reconstruction with the vascularized fibula free flap and had a minimum follow-up of 5 years. Comparisons between preoperative and postoperative measurements—as well as postoperative comparisons between condyle-reconstructed and condyle-preserved patients—were conducted. The mean follow-up was 76.9 (± 19.0) months (range, 60–120). The average age at intervention was 9.23 (± 3.8) years. Mean AI was 15.31 (± 1.81) preoperatively and 3.59 (± 0.97) postoperatively. Differences between preoperative and postoperative measurements were statistically significant in all the assessed parameters (p <0.001). Postoperative differences between the condyle-reconstructed and the condyle-preserved groups were not significant (p >0.05). No secondary procedures were required to enhance symmetry in the late postoperative period. Mandibular reconstruction using the vascularized fibula free flap provides adequate restoration of facial symmetry that could be predictably maintained throughout the developmental period in children and adolescents, regardless of the need for condylar reconstruction. [ABSTRACT FROM AUTHOR]

Abstract Background To explore the masticatory performance in patients undergoing an osteo(cutaneous) free fibula (OFF) flap for mandible reconstruction by a prospective design. Methods A total of 56 patients who had undergone OFF flap reconstructions for mandibular reconstruction secondary to malignant (squamous cell carcinoma) or benign (ameloblastoma) tumor resection were prospectively enrolled. They were asked to complete the masticatory performance test by the weigh method and the chew domain of the University of Washington quality of life questionnaire (version 4) preoperatively and at 3, 6, and 12 months postoperatively. The pair nonparametric test was used to analyze the dynamic change of masticatory performance and subjective chew function. Results Fifty-one patients were included for analysis finally. The mean masticatory performance for patients with malignant tumors were 53.4% ± 10.3%, 36.4% ± 10.3%, 42.6% ± 9.6%, 52.8% ± 10.9%, and 53.1% ± 11.8% preoperatively, at 2 weeks, 3 months, 6 months, and 12 months postoperatively, respectively. Compared with the preoperative level, the masticatory performance had a significant reduction immediately after surgery (p

Nonunion is one of the most dreaded complications after operative treatment of mandible fractures or after mandible reconstruction using vascularized and non-vascularized bone grafts. Often diagnosis is made at advanced stage of disease when pain or complications occur. Devices that monitor fracture healing and bone regeneration continuously are therefore urgently needed in the craniomaxillofacial area. One promising approach is the strain measurement of plates. An advanced prototype of an implantable strain measurement device was tested after fixation to a locking mandible reconstruction plate in multiple compression experiments to investigate the potential functionality of strain measurement in the mandibular region. Compression experiments show that strain measurement devices work well under experimental conditions in the mandibular angle and detect plate deformation in a reliable way. For monitoring in the mandibular body, the device used in its current configuration was not suitable. Implant strain measurement of reconstruction plates is a promising methodical approach for permanent monitoring of bone regeneration and fracture healing in the mandible. The method helps to avoid or detect complications at an early point in time after operative treatment. [ABSTRACT FROM AUTHOR]

The human mandible reconstruction is widely used in medical cosmetology, criminal investigation, archaeology and anthropology. This study is devoted to rapidly reconstructing 3D personalized mandibles, especially when the mandible is severely damaged or totally lost. An example-oriented method based on principal component analysis (PCA) is used to reconstruct the 3D shapes of mandibles. The predictor variable is an input cranium, while the response variables is a full mandible. The linear relationship between the cranium and mandible is obtained based on a number of skull samples, which is used as prior knowledge. The PCA method reduces the dimensionality of the skull data to improve the accuracy and speed of the reconstruction process. Experiments are conducted based on 215 skull models in the Chinese craniofacial database established in the study of craniofacial morphology informatics at Beijing Normal University. In our experiments, parameters are modified to help improve the reconstruction results. The proposed method exhibits higher accuracy than state-of-the-art methods according to comparison experiments results. Moreover, this method is robust to various types of input data and noise. Results indicate the proposed method is a fast and feasible tool for reconstructing 3D customized full mandibles. [ABSTRACT FROM AUTHOR]

In this study, we investigated the feasibility of using a geometrically designed anterior ramus graft to reconstruct lateral mandibular defects. This was achieved by assessing the anatomical dimensions of the mandibular ramus on computed-tomographies. The design sequence and application of the graft was also demonstrated using one of our cases. The following dimensions were measured; a and b - horizontal length from mid-ramus to the posterior and anterior ramus border respectively, c - longest length of the graft, Mp - width at the centre of the ramus, h - vertical length of the angle at its cross-section, w - horizontal length of the angle at its cross-section, x - cross-sectional area along the mandible angle. A total of 80 mandibular rami were examined. The mean length of a, b, c were 17.3 ± 1.8mm, 15.9 ± 1.2mm, 54.6 ± 3.8mm, respectively. The mean width of Mp was 9.8 ± 1.1mm. The mean cross section area of Eo- Md (x) was 326.7 ± 67.8mm². The average length of h and w were 26.5 ± 3.2 and 15.6 ± 2.1 mm, respectively. The use of virtual surgical planning (VSP) to geometrically design the graft was also described. Together with VSP, the anterior ramus bone graft will allow for reconstruction of the mandible with greater surgical efficiency, reduced complexity and without the need for extra-oral bone harvest. This may be an useful alternative in situations where simpler reconstructive procedures are preferred. [ABSTRACT FROM AUTHOR]

Background: Vascularized bone grafting (VBG) is preferred for mandibular reconstruction post-tumor ablation. Although various bone-free flaps are used, their application is compromised by limitations including insufficient bone volume and poor shape. Here, we report mandibular reconstruction using axial split-step osteotomy with an iliac crest-free flap., Methods: Over December 2018-November 2020, 12 patients underwent mandibular reconstruction via axial split osteotomy using a free iliac-crest flap., Results: The preoperative iliac-crest length was 5.7-9.5 mm (median, 7.5 cm); the mean post-axial split-osteotomy iliac-crest length increased to 9.59 mm (range, 6.34-15.15 mm). All patients presented with initial healing 2 weeks postoperation; good bone healing was achieved in all grafted flaps by the third month of follow-up., Conclusions: We propose a new axial split-step osteotomy technique using free iliac-crest flaps for mandibular reconstruction. We demonstrated this novel technique's reliability for safe and effective bone lengthening and establishing a reliable occlusal relationship., (© 2024 Wiley Periodicals LLC.)

Fibrous dysplasia is a benign bone disease in children and young adults. This is characterized by the replacement of normal bone with fibrous tissue along with immature woven bone. Fibrous dysplasia is a rare disorder and has variable presentations that pose challenges in diagnosis and treatment. Decisions are made on a case-by-case basis, depending on the symptoms, location, or possible complications. Symptomatic lesions are treated with surgical resection. cosmetic concerns of the patients are taken care of by surgical contouring. For any unresectable or recurrent lesion, bisphosphonate therapy can be used as a form of medical management., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Scientific Review Board, Saveetha Dental College, Chennai, India issued approval SRB/SDC/OMFS-2206/22/059. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Singh et al.)

Background: Jaw reconstruction after complex post-traumatic fracture is still a challenge for surgeons using traditional surgery. Virtual surgical planning has proven to be a valid tool for managing these fractures. The aim of this study is to quantitatively evaluate the VSP effectiveness compared to traditional surgery in the management of complex mandibular fractures., Methods: 30 patients with diagnosis of complex mandibular fracture were enrolled and divided in two groups: Group A (virtually planned surgery), The plate was pre-modeled and employed during the surgery; Group B (traditional surgery), the plate was shaped directly during the surgery. Virtually planned and post-operative Computer Tomography were after compared for both the groups to highlight discrepancies in mm., Results: Fracture surgical reduction was successful without intraoperative complications. In Group A, all the mean discrepancies' values were <1 mm while in Group B the values were included between 1.36 and 1.94 mm. The mean operative time was 69 min for Group A, while 106 min for Group B., Conclusions: Fracture virtual reduction and realization of pre-modeled plate are able to guarantee a more anatomically correct reduction and a decrease in operating times. These outcomes translate into a decrease in both short and long-term complications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Masson SAS.. All rights reserved.)

As the fibula free flap became the gold standard in mandibular reconstruction that required both hard tissue and soft tissue, various methods have been sought to solve the height discrepancy between the mandible and fibula. The purpose of this paper was to propose a surgical option that combined the microvascular fibula free flap with a 3D-bioprinted, patient-specific polycaprolactone (PCL) implant as a safe and simple novel method that achieved the best functional and aesthetic results in mandibular reconstruction surgery for young patients with malignant tumors. The patient’s reconstructed mandible maintained volume symmetry without any deformation or complications for over 6 years. Computer-aided design/computer-aided manufacturing (CAD/CAM) and 3D printing technology enabled accurate and safe surgical results.

Purpose: The primary objective of this prospective cohort study was to evaluate primary and secondary implant stability values of implants placed into healed free fibula-reconstructed mandibles. The secondary objective was to investigate whether a correlation existed between primary implant stability and the quantity of cortical bone-implant contact and of cortical fibular bone in contact with the implants. Materials and Methods: The study participants are patients enrolled in a registered trial (No. CTRI/2012/07/002764). Patients with healed segmental mandibular reconstruction by means of free fibula flaps were chosen to undergo implant-supported dental rehabilitation. Preoperatively, computed tomography (CT) scans were used to measure the quality (density) of bone in Hounsfield units (HU). Implant stability quotients (ISQ) were obtained at the time of implant placement (primary), as well as 6 months later (secondary). The amount of cortical bone-to-implant contact (CBIC) was measured from postoperative panoramic radiographs using image analysis software (Image J). A paired t test was used to compare the mean primary and secondary ISQ values. Pearson correlation was used to determine the relationship between primary ISQ and CBIC. Statistical significance was set at the 5% level (P < .05). Results: Of 54 patients (156 implants) who were enrolled, 35 (104 implants) were assessed. The reasons for exclusion were as follows: 11 patients (34 implants) had inadequate preoperative CT documentation, 7 patients (16 implants) had unreadable panoramic radiographs, and 1 patient (2 implants) had partial necrosis of the flap. The mean primary and secondary ISQ values were 78.1 (SD = 4.3) and 77.8 (SD = 4.6), respectively (P = .348). The mean density of cortical fibula bone was 1,344 HU (SD = 93.6). The mean CBIC was 3.7 mm (SD = 1.4). The study results showed a positive correlation between CBIC and implant stability (r = 0.274, P = .005). Conclusion: This study showed no differences in primary and secondary ISQ values of implants placed into the fibula. Implant stability quotients correlated positively with CBIC. [ABSTRACT FROM AUTHOR]

The management of patients with post-traumatic and post-operative mandibular defects is a major challenge even for experienced surgeons. Performing traditional reconstructive interventions with the use of bone autografts is always confronted with the problem of inconsistency between the shape, architecture, a biological. An alternative to conventional bone grafting is the use of digital protocol and CAD /CAMtechnology, which allows fabricating different types of customised medical devices. All patients underwent reconstructive and restoring interventions with the use of patient-specific titanium implants guided by a full digital protocol.Patients were examined in compliance with the standard scheme. To repair the defects, PSIs were fabricated with the use of selective laser sintering of titanium.The introduction of digital technologies and computer technique of diagnosing, planning and implementation of surgical interventions has been the main direction aimed at the improving the accuracy and predictability of reconstructive restorative surgery. Among the main achievements in this direction are the improvement of software and methods of computer modeling, as well as the introduction of CAD /CAMtechnology.The use of CAD /CAMtechnologies, in particular, navigational surgical templates and patient-specific implants for the repair of mandibular defects ensures a high level of accuracy and predictability.

Background: To explore the masticatory performance in patients undergoing an osteo(cutaneous) free fibula (OFF) flap for mandible reconstruction by a prospective design. Methods: A total of 56 patients who had undergone OFF flap reconstructions for mandibular reconstruction secondary to malignant (squamous cell carcinoma) or benign (ameloblastoma) tumor resection were prospectively enrolled. They were asked to complete the masticatory performance test by the weigh method and the chew domain of the University of Washington quality of life questionnaire (version 4) preoperatively and at 3, 6, and 12 months postoperatively. The pair nonparametric test was used to analyze the dynamic change of masticatory performance and subjective chew function. Results: Fifty-one patients were included for analysis finally. The mean masticatory performance for patients with malignant tumors were 53.4% ± 10.3%, 36.4% ± 10.3%, 42.6% ± 9.6%, 52.8% ± 10.9%, and 53.1% ± 11.8% preoperatively, at 2 weeks, 3 months, 6 months, and 12 months postoperatively, respectively. Compared with the preoperative level, the masticatory performance had a significant reduction immediately after surgery (p < 0.001), followed by a return to the baseline level within three months. A similar trend was noted for those with benign tumors. The mean score of chew domain for patients with malignant tumors were 100 ± 0, 54.3 ± 32.9, 81.4 ± 24.5, and 92.9 ± 17.8 preoperatively, at 3 months, 6 months, and 12 months postoperatively, respectively. Compared with the preoperative level, the subjective chew function was greatly affected within the first three months (p < 0.001), and it gradually recovered to the baseline level in the following nine months. A similar trend was noted in patients with benign tumors. Conclusions: The masticatory performance and subjective chew function was significantly affected after OFF flap reconstructions in the short term, but both recovered to the preoperative levels within 9–12 months. [ABSTRACT FROM AUTHOR]

Background: Mandibular reconstruction in children is uncommon and implies specific concerns when compared to the adult patient, namely regarding long-term results and growth considerations. Vascularized or non-vascularized bone or cartilage flaps can be used. Commonly used bone-donor sites include fibula, iliac crest, and scapula, all of which with the possibility of including growth centers that can be theoretically used for a "growing bone" reconstruction. Methods: We retrospectively evaluate a series of 6 pediatric patients who underwent mandibular reconstruction with iliac crest free flaps between 2005 and 2015 in our center. A sequential 3D analysis of the volume and dimensions of the bone-flap was done through time in order to evaluate the growth pattern of reconstructed bone. Results: From January 2000 to January 2015, a total of 6 pediatric patients have had a mandibular defect reconstructed with free iliac crest flap. One was lost to follow-up and was not included in the study. After evaluation of flap dimensions and volume at early post-op and 5 years post-op, no significant increase in flap dimensions or volume was observed. No native mandible growth impairment was observed nor gross maxillo-mandibular deformity, with all the patients achieving an esthetically pleasant appearance. Conclusions: Pediatric mandible reconstruction is a challenge for the reconstructive surgeon. Although flap growth was not observed in this series, overall facial symmetry was obtained during growth with no gross maxillo-mandibular deformity. Level of Evidence: Level IV, therapeutic study. [ABSTRACT FROM AUTHOR]

BackgroundThis study was conducted to evaluate the feasibility, clinical outcomes, and accuracy of patient-specific 3D-printed miniplates for mandible reconstruction with fibula free flaps.MethodsA feasibility study was conducted with 8 patients. Following virtual planning, patient-specific 1.0 mm titanium non-locking miniplates were produced via laser selective melting. 3D-printed cutting and drilling guides were used for segmental mandible resection and flap harvesting. Flap fixation was performed with two 4-hole miniplates and 2.0 mm non-locking screws (screw length 7 mm) for each intersegmental gap. Clinical follow-up was at least 6 months. Preoperative and postoperative CT/cone beam CT data were used for 3D accuracy analysis and evaluation of bone healing. Plate-related complications were monitored clinically.ResultsPatient-specific miniplate fixation of all flaps was successfully conducted (4 mono-segmental, 4 dual-segmental) with high accuracy (3.64 ± 1.18 mm) between the virtual plan and postoperative result. No technical complications were encountered intraoperatively. Osseous union occurred in all intersegmental gaps (1 partial, 18 complete) after 10 ± 2 months. No material fracture, dislocation, or plate exposure was observed.ConclusionsBased on this pilot observational study including a limited number of patients, free flap fixation for mandibular reconstruction with patient-specific 3D-printed miniplates is feasible and associated with high accuracy, bone healing, and remote soft tissue complications.

Copyright of Turkiye Klinikleri Journal of Dental Sciences is the property of Turkiye Klinikleri and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: To conduct a systemic review for guidance regarding the application of templates in mandibular reconstruction with vascularised iliac flaps. Methods: By searching PubMed, EMBASE and the Cochrane Library and collecting relevant literature, information about the types and accuracy of templates was extracted. Data relating to surgical time were also included for further analysis. Results: Eight studies were included. The data analysis showed that the accuracy of operations with templates was higher than that of conventional surgery. The mean deviation was between 0.70 and 3.72 mm. The operational time was shortened to 314.4 minutes and the graft ischemic time was reduced to 15.6 to 26.8 minutes. Application of functional or specifically designed templates can improve the accuracy and shorten surgical time. Conclusion: Templates can increase the accuracy and efficiency of mandibular reconstruction with vascularised iliac flaps, which will benefit patients' prognosis and subsequent functional restoration. Further studies should be conducted into application of templates to improve the accuracy of reconstructions. [ABSTRACT FROM AUTHOR]

Background: This study aimed to introduce a novel loop neurorrhaphy technique using an innervated vascularized iliac bone flap (VIBF) with vascularized ilioinguinal nerve (IIN) to reconstruct the inferior alveolar nerve (IAN) and preserve lower lip sensation simultaneously with mandibular reconstruction. Methods: This study prospectively included patients who underwent mandibular reconstruction using VIBF from May 2018 to April 2020. Subjects were allocated into two groups: (1) Group I; innervated VIBF with loop neurorrhaphy (IIN doubly anastomosed with IAN and mental nerve), (2) Group II (control); conventional VIBF. Evaluation was done with operative time, intraoperative indocyanine green (ICG), lower lip sensory assessment (two‐point discrimination [TPD] test and current perception threshold [CPT]), and drooling. Results: Twelve patients were included; 6 in each group, (7 males and 5 females), age ranging from 18 to 57 years (average: 36.75 years). In all cases, intraoperative perfusion of IIN was confirmed by ICG. Group I showed a statistically significant more flap harvesting time compared with group II (mean difference, 5.67 min; P = 0.0091). There was a significant difference in sensory recovery favoring group I (P < 0.05). The TPD results in group I showed an average of 9.8 ± 6.9 mm and 6.2 ± 5.7 mm on operated and non‐operated sides, while Group II showed a poor sensory recovery, and the TPD showed an average of 24.6 ± 6.7 mm and 8.4 ± 2.3 mm on operated and non‐operated sides. The CPT results showed a significant difference between both groups. In Group I, the extent of drooling was 3.16 ± 0.75, while in Group II, the score was 1.6 ± 0.81, revealing a significant difference favoring Group I. Conclusions: Concurrent mandibular reconstruction using VIBF and loop neurorrhaphy with vascularized IIN to reconstruct IAN successfully restore lower jaw form and preserve lip sensation. [ABSTRACT FROM AUTHOR]