Sequential free fibula transfers: Quality of life and systematic review.

BACKGROUND: Successive osteoseptocutaneous fibula transfers for jaws reconstruction are rare but important options. This study contributes patient-reported and clinical outcomes, as well as systematically reviews all existing reports. METHODS: All sequential fibula transfers performed by the senior author were reviewed from a prospectively managed database, including University of Washington quality of life (UWQoL). Systematic review was conducted in PubMed and Cochrane databases for similar publications. RESULTS: Eighteen patients (average age 51.5 years) received sequential fibulas (mean 4.7 years between reconstructions). Secondary fibulas more often had benign indications (72.2% vs. 33.3%, p = .04), most commonly osteoradionecrosis (38.9%). At a mean follow-up of 30.5 months, the average interincisal distance increased from 21.8 to 27.6 mm, and 92.3% tolerated an oral diet following the second fibula. Eight patients completed the UW-QoL before and after the second fibula, and three prior to the first fibula. Composite physical function was significantly decreased from 96.7 prefibula reconstruction to 63.3 following the first (p < .001) and 64.2 after the second fibula (p < .001). There were no differences in other domains. The systematic review yielded six articles reporting 56 patients (mean 39 months between fibulas). Secondary fibulas were performed for repeat malignancy (45%) and osteoreadionecrosis (39%), resulting in elevated tube feeding from 20% following the first to 39% following the second, but overall high quality of life in two studies. CONCLUSIONS: Sequential osteoseptocutaneous fibula reconstructions of jaws are often performed for benign indications such as osteoradionecrosis. Overall function and QoL are comparable with those following the first fibula transfer.

Comparison of condylar position after free fibular flap mandibular reconstruction using computer-assisted and traditional techniques.

OBJECTIVES: To compare the changes in condylar position after mandibular reconstruction with free fibular flap(FFF) and the differences between computer-assisted techniques and traditional methods on CT images. METHODS: Thirty-four patients who underwent mandibular reconstruction with free fibular flap were selected according to the inclusion and exclusion criteria. In the 3D group, virtual surgical planning (VSP) with osteotomy cutting plate and placement guiding plate were used, while the traditional group underwent freehand reconstruction. The CT data of 68 temporomandibular joints (TMJs) were recorded before and immediately after surgery. The condylar position was evaluated by measuring the anterior space (AS), posterior space (PS) and superior space (SS), and the ln (PS/AS) was calculated according to the method proposed by Pullinger and Hollender. RESULTS: In the patients included in the 3D group, the condyle on the ipsilateral side moved slightly backward; however, in the patients in the traditional group, the ipsilateral side moved considerably anteroinferior. No obvious changes on the contralateral side were noted. In the 3D group, 33% of ipsilateral condyles were in the posterior position postoperatively when compared with the preoperative position (13%). In the traditional group, the number of ipsilateral condyles in the anterior position increased from 4 to 10, accounting for 53% postoperatively. Contrary to the traditional group, the 3D group presented less condylar displacement on the ipsilateral side postoperatively. CONCLUSIONS: This study showed a decreased percentage of change in condylar position postoperatively when VSP was used. Virtual surgical planning improved the accuracy of FFF mandibular reconstruction and made the condylar position more stable.

To what extent can mastication functionality be restored following mandibular reconstruction surgery? A computer modeling approach.

STATEMENT OF PROBLEM: Advanced cases of head and neck cancer involving the mandible often require surgical removal of diseased sections and subsequent replacement with donor bone. During the procedure, the surgeon must make decisions regarding which bones or tissues to resect. This requires balancing tradeoffs related to issues such as surgical access and post-operative function; however, the latter is often difficult to predict, especially given that long-term functionality also depends on the impact of post-operative rehabilitation programs. PURPOSE: To assist in surgical decision-making, we present an approach for estimating the effects of reconstruction on key aspects of post-operative mandible function. MATERIAL AND METHODS: We develop dynamic biomechanical models of the reconstructed mandible considering different defect types and validate them using literature data. We use these models to estimate the degree of functionality that might be achieved following post-operative rehabilitation. RESULTS: We find significant potential for restoring mandibular functionality, even in cases involving large defects. This entails an average trajectory error below 2 mm, bite force comparable to a healthy individual, improved condyle mobility, and a muscle activation change capped at a maximum of 20%. CONCLUSION: These results suggest significant potential for adaptability in the masticatory system and improved post-operative rehabilitation, leading to greater restoration of jaw function.

Technical refinements of the scapular tip-free flap for mandibular reconstruction.

BACKGROUND: The use of scapular tip chimeric free flaps (STFFs) for reconstructing mandibular defects has recently become popular, but its utility relative to other bone-containing free flaps remains debatable. The aim of the report is to describe how technical modification of STFF impacted in its use for mandibular reconstruction also commenting results obtained in a unicentric series of patients. PATIENTS AND METHODS: Patients undergoing mandibular reconstruction using an STFF from January 1, 2014 to June 1, 2022 were retrospectively enrolled in this report. We collected data on chimeric flap type, bone management, vascular pedicles, and the final outcomes. In total, 31 patients (13 men and 18 women) with a mean age of 68 years were enrolled. According to the classification system of Urken, 15 patients had body defects, while 7 had ramus defects, another 7 had symphysis defects, and 2 had both ramus and bodily defects. STFF was always harvested working in two equips simultaneously, in supine position. Dissection included preparation of chimeric components of the flap as latissimus dorsi, serratus and scapular tip. After pedicle dissection scapular bone was cut basing on reconstructive needing with a rectangular (stick) shape including the border of the scapula. In cases of longer bone harvesting, circumflex pedicle was also included to perfuse the upper portion of the scapular border. In five cases, the STFF was harvested with only the scapular angle component, and was thus a composite osteomuscular flap; for the remaining 26 cases, a chimeric STFF was used. Circumflex pedicle was included for eight patients. Six of the seven patients with symphyseal defects underwent a single osteotomy. RESULTS: The average length of the harvested was 69.92 mm (maximum length = 104 mm). The average height of transplanted bone was 26.78 mm (maximum height = 44.2 mm). Mouth-opening was normal in 25 patients, limited in 6 patients, and severely impaired in no patients. The cosmetic results were rated as excellent by 20 patients, good by 8 patients, and poor by 3 patients. CONCLUSION: The STFF is an excellent option for mandibular reconstruction when other flaps are not available and for patients in poor general condition. Technical innovations here presented made possible to harvest long bone segments with accurate shape thanks to osteotomies if needed and with adequate soft tissues components of the chimeric flap, ensuring satisfactory functional and cosmetic results.

Functional and esthetic outcomes of virtual surgical planning versus the conventional technique in mandibular reconstruction with a free fibula flap: A retrospective study of 24 cases.

This study aimed to compare the functional and esthetic results in patients following mandibular reconstruction with a free fibula flap (FFF) by virtual surgical planning (VSP) versus the conventional technique. Patients who had undergone mandibular reconstruction with a FFF by VSP or the conventional technique were retrospectively assessed. The two groups were compared regarding functional and esthetic variables with appropriate scales preoperatively, intraoperatively, and postoperatively. Twenty-four patients were evaluated in two groups: conventional (n = 8) and VSP (n = 16). The mean amount of mandibular asymmetry was 2.62 mm (SD = 1.59) in the conventional group and 1.19 mm (SD = 1.32) in the VSP group. Of the patients who underwent conventional surgery, 12.5% had mandibular asymmetry of <2 mm and 87.5% had asymmetry of 2-5 mm. Of the VSP patients, 61.5% had mandibular asymmetry of <2 mm and 38.5% had mandibular asymmetry of 2-5 mm (p = 0.03). The mean difference in size of mandibular angle on the surgical and control sides was not significantly different between the two groups (p = 0.62). The difference in mean length of the mandibular body on the surgical side relative to the control side was not significant between the two groups (p = 0.75). Differences in functional variables between the two groups were not significant. Within the limitation of the study, it seems that the VSP technique resulted in better facial symmetry and superior esthetic outcomes compared with the conventional technique.

Streamlining complex mandibular fracture treatment: Integration of virtual surgical planning and short-segment drilling guides.

This study aimed to evaluate the feasibility and accuracy of a combined virtual surgical planning (VPS) and short-segment drilling guides (SSDGs) workflow for the treatment of complex mandibular fractures. Consecutive patients with complex mandibular fractures underwent treatment using the VPS and SSDGs workflow from August 2020 to April 2022. Various mandibular landmarks were compared between the preoperative virtual surgical plan and postoperative data, including condylar distance (CoD), mandibular angle width (GoL-GoR), GoMeGo angle (∠GoL-Me-GoR), the difference in mandibular angles between the left and right sides (Δ∠Co-Go-Me), and the difference in length between the left and right mandibular body (ΔGo-Me). Additionally, preoperative preparation time and surgical duration were retrospectively analyzed and compared to conventional surgery. All 14 consecutive patients with complex mandibular fractures achieved successful reduction using the VPS and SSDGs workflow. Three-dimensional comparison revealed a mean deviation distance of 0.91 ± 0.50 mm and a root-mean-square deviation of 1.75 ± 0.47 mm between the preoperative designed mandible model and the postoperative mandible model. The percentage of points with deviation distances less than 2 mm, 1 mm, and 0.5 mm between preoperative and postoperative models were 78.47 ± 8.87 %, 60.02 ± 14.28 %, and 38.64 ± 15.48 %, respectively. There were no significant differences observed in CoD, GoL-GoR, ∠GoL-Me-GoR, Δ∠Co-Go-Me, and ΔGo-Me between preoperative virtual surgical planning and postoperative measurements. Furthermore, no significant differences were found in the injury-to-surgery interval, admission-to-surgery interval, and surgical duration between the workflow and conventional surgery. The combined VPS and SSDGs workflow proved to be an accurate and feasible method for treating complex mandibular fractures. It offers advantages such as minimal preoperative preparation time and the ability to precise transfer screw positions of the pre-bent reconstruction plate during surgery. This approach is particularly suitable for managing complex mandibular fractures.

Prediction of jaw opening function after mandibular reconstruction using subject-specific musculoskeletal modelling.

BACKGROUND: Mandibular reconstruction patients often suffer abnormalities in the mandibular kinematics. In silico simulations, such as musculoskeletal modelling, can be used to predict post-operative mandibular kinematics. It is important to validate the mandibular musculoskeletal model and analyse the factors influencing its accuracy. OBJECTIVES: To investigate the jaw opening-closing movements after mandibular reconstruction, as predicted by the subject-specific musculoskeletal model, and the factors influencing its accuracy. METHODS: Ten mandibular reconstruction patients were enrolled in this study. Cone-beam computed tomography images, mandibular movements, and surface electromyogram signals were recorded preoperatively. A subject-specific mandibular musculoskeletal model was established to predict surgical outcomes using patient-averaged muscle parameter changes as model inputs. Jaw bone geometry was replaced by surgical planning results, and the muscle insertion sites were registered based on the non-rigid iterative closest point method. The predicted jaw kinematic data were validated based on 6-month post-operative measurements. Correlations between the prediction accuracy and patient characteristics (age, pathology and surgical scope) were further analysed. RESULTS: The root mean square error (RMSE) for lower incisor displacement was 31.4%, and the error for peak magnitude of jaw opening was 4.9 mm. Age, post-operative infection and radiotherapy influenced the prediction accuracy. The amount of masseter detachment showed little correlation with jaw opening. CONCLUSION: The mandibular musculoskeletal model successfully predicted short-range jaw opening functions after mandibular reconstruction. It provides a novel surgical planning method to predict the risk of developing trismus.

Long-term stability of jaw reconstruction with microvascular bone flaps: A prospective longitudinal study.

OBJECTIVES: Microvascular bone flap jaw reconstruction has achieved satisfactory clinical outcomes. However, little is known about the long-term stability of the reconstructed jaw. This prospective longitudinal study aimed to investigate the long-term stability of jaw reconstruction and factors that were associated with it. METHODS: Patients with successful computer-assisted osseous free-flap jaw reconstruction in the Department of Oral and Maxillofacial Surgery, Queen Mary Hospital, Hong Kong were recruited for this prospective longitudinal study. The three-dimensional jaw models at the pre-operative plan, post-operative 1-month, and 2 years were aligned and compared. RESULTS: A total of 69 patients were recruited, among which 48 patients were available for the long-term analysis. Compared to 1-month after surgery, further deviation from the pre-operative plan was observed at post-operative 2 years. Lack of accuracy in surgery, segmental mandible resection especially with the involvement of mandible angles, and post-operative radiation therapy were identified as the significant factors affecting the positional stability of the reconstructed jaw (p < 0.05). Stable reconstruction was observed in the subgroup analysis of patients without post-operative radiation therapy. CONCLUSION: Up to the best of our knowledge, this is the first prospective longitudinal study reporting the long-term stability of jaw reconstruction and its affecting factors. Our data demonstrated that the reconstructed jaw position lacked stability over the postoperative period. How to improve long-term stability of reconstructed jaw thus optimize the functional outcomes warrants further studies.

Evaluating the benefit of virtual surgical planning on bony union rates in head and neck reconstructive surgery.

OBJECTIVES: Virtual surgical planning (VSP) has gained acceptance because of its benefits in obtaining adequate resection, achieving cephalometric accuracy, and reducing operative time. The aim of this study is to compare the rate of union between VSP and free-hand surgery (FHS), identify predictors of non-union and evaluate the difference in operative time. METHODS: Post-operative CT were retrospectively reviewed for 123 patients who underwent maxillary or mandibular reconstruction between 2014 and 2021 using either VSP or FHS. Each apposition was graded as complete, partial or non-union. The rate of union, risk difference and inter-rater reliability were calculated. The difference in operative time was assessed. Predictors of non-union were identified using logistic regression. RESULTS: A total of 326 appositions were graded (VSP n = 150; FHS n = 176). The rates of complete and partial union were higher with VSP than FHS (74.7% vs. 65.3%; 18% vs. 15.9%, respectively, p = 0.01). Non-union was found at a higher rate with FHS than with VSP (18.7% vs. 7.3%). The non-union risk difference was 11.4. FHS, major complications and apposition at the native bone were predictors of non-union (OR 2.9, p = 0.02; OR 3.4, p = 0.01; OR 2.5, p = 0.05, respectively). The mean surgical time was shorter with VSP than with FHS (265.3 vs. 381.5 min, p < 0.001). The inter-rater agreement was high (k = 0.85; ICC = 0.86). CONCLUSION: VSP demonstrated significantly higher bony union rates and shorter operative time. FHS, development of major complications and apposition with native bone correlated with non-union.

Impact of virtual surgical planning and three-dimensional modeling on time to surgery in mandibular reconstruction by free fibula flap.

PURPOSE: Mandible reconstruction using a free fibula flap (FFF) is preferably performed with virtual surgical planning (VSP) to potentially improve functional and aesthetic outcomes. However, VSP is time-consuming. This study aims to assess the impact of VSP on time to surgery (TS). MATERIALS AND METHODS: All patients who underwent FFF for oral cavity cancer between 2007 and 2020 were included. Time to surgery (from the date of the first consultation to the surgery date) was compared between patients without VSP and with VSP. In our department, VSP and 3D modeling were performed by an external engineering laboratory. RESULTS: One hundred sixty-five patients were included retrospectively. VSP was utilized for 90 patients (55%). The mean time to surgery was 31 ± 16 days for patients undergoing conventional surgery without VSP and 44 ± 19 days for patients with VSP (p < 0.001). No clinical or tumoral characteristic were associated with a TS extended, except for the utilization of VSP (p < 0.001). By constituting groups of 25 consecutive patients, there is no difference in TS between the groups. CONCLUSION: The use of VSP significantly increased the time to surgery in our study, unrelated to clinical differences or year of surgery. This delay may have an impact on oncologic outcomes, so it should be considered in the care organization for each patient. Implementing new procedures to reduce this difference is warranted.

The comparison between various methods of mandibular reconstruction based on finite element analysis.

The Mandible can be damaged by pathological factors, tumors, trauma, infection, and needs a surgical operation for reconstruction and restoring function. There are different methods for the reconstruction of mandible. Based on the surgical approach, primary reconstruction of mandible by reconstruction plate after resection is necessary for maintaining mandibular symmetric and esthetic of the lower third of the face. A finite element model of mandible and masticatory muscles was produced from a normal person (male with 35-year-old). The normal model was resected from the left sixth tooth to the second tooth. The pathological model was reconstructed in different conditions by macro plate. Different conditions were analyzed and compared based on bite force on right fifth tooth, stress developed on screws and macro plate. The finite element analysis results showed that maximum bite force and lower stress on screws were seen in the pathological model (condition 5) when one macro plate and six screws were inserted in the mid-body. The findings showed that the use of two macro plates causes lower stress on it than when we use one. Use of one macro plate and six screws is the best choice in mandibular immobilization which decrease the stress applied on bone and increase the bite force. Because of less stress developed on macro plates and screws, use of two macro plates or one macro plate in mid-body area are also preferred.

Free flap jaw reconstruction with dental implantation: A single-institution experience.

BACKGROUND: We sought to review our institution's experience with dental implant placement in free flap jaw reconstruction to determine factors impacting restoration of dental occlusion. METHODS: Exactly 48 patients underwent free flap jaw reconstruction with or without dental restoration from 2017 to 2022. Primary outcome was achievement of restored dental occlusion after jaw free flap reconstruction. RESULTS: A total of 48 patients with a mean age of 59.8 ± 16.4 years underwent jaw reconstruction from 2017 to 2022. Ten patients (20.8%) received osteointegrated dental implants. Two patients received a temporary dental prosthesis, 12 ± 4 months after initial reconstruction. Three patients received a final prosthesis, with a mean time to final prosthesis of 17.7 ± 12.4 months. Five patients did not receive any prosthesis despite placement of implants. CONCLUSION: A minority of patients received dental implant placement with free flap jaw reconstruction and only a small subset of these received a definitive dental prosthesis.

In-house virtual surgical planning and guided mandibular reconstruction is less precise, but more economical and time-efficient than commercial procedures.

BACKGROUND: To compare an in-house and a commercially available surgical planning solution for mandibular reconstruction in terms of postoperative reconstruction accuracy and economic benefit. METHODS: Twenty-nine consecutive patients with advanced oral squamous cell carcinoma (OSCC) requiring segmental mandibular reconstruction were enrolled. Fifteen patients underwent in-house surgical planning and 14 patients underwent a commercially available planning solution. A morphometric comparison of preoperative and postoperative computed tomography (CT) data sets and a cost-benefit comparison were performed. RESULTS: Volumes of planned and reconstructed bone segments differed significantly for both in-house planning (p = 0.0431) and commercial planning (p < 0.0001). Significant differences in osteotomy angles were demonstrated for in-house planning (p = 0.0391). Commercial planning was superior to in-house planning for total mandibular deviation (p = 0.0217), intersegmental space volumes (p = 0.0035), and lengths (p = 0.0007). No significant difference was found between the two planning solutions in terms of intersegmental ossification and the incidence of wound healing disorders. In-house planning took less time than commercial planning (p < 0.0001). Component manufacturing costs (p < 0.0001) and total cumulative costs (p < 0.0001) were significantly lower for in-house planning. CONCLUSIONS: In-house surgical planning is less accurate but has a cost advantage and could be performed in less time.

Efficacy of personalized 3D-printed osteotomy guide in maximizing fibular utilization and minimizing graft length for reconstruction of large mandibular defect.

OBJECTIVE: The study addresses the long-standing challenge of insufficient length in vascularized fibular flaps when reconstructing large mandibular defects that require dual-barrel grafts. Employing personalized 3D-printed osteotomy guides, the study aims to optimize fibular utilization and minimize the required graft length. MATERIAL AND METHODS: Two reconstruction methods for distal bone defects were compared: a fold-down (FD) group that employed a specialized osteotomy guide for folding down a triangular bone segment, and a traditional double-barrel (DB) group. Metrics for comparison included defect and graft lengths, as well as the graft-to-defect length ratio. Postoperative quality of life was assessed using the University of Washington Quality of Life questionnaire (UW-QoL). RESULT: Both FD and DB groups achieved successful mandibular reconstruction. Despite larger defects in the FD group (117 ± 31.35 mm vs 84 ± 35.34 mm, p = 0.028), the used fibula length was not statistically longer in the FD group. The median ratio of graft-to-defect length was also lower in the FD group (1.327 vs 1.629, p = 0.024), suggesting that FD required only 82.47% of the graft length needed in the DB approach. Quality of life scores post-surgery were comparable between the groups. CONCLUSION: Personalized 3D-printed osteotomy guides enhance fibula graft efficacy for reconstructing larger mandibular defects, necessitating shorter graft lengths while preserving postoperative quality of life. CLINICAL RELEVANCE: This study confirms the utility of 3D printing technology as an effective and precise tool in orthopedic surgery, particularly for complex reconstructions like large mandibular defects. It suggests a viable alternative that could potentially revolutionize current practices in bone grafting.

Scope of magnesium ceria nanocomposites for mandibular reconstruction: Degradation and biomechanical evaluation using a 3-dimensional finite element analysis approach.

Magnesium/Ceria nanocomposites (Mg/xCeO2 NCs (x = 0.5 %, 1 % and 1.5 %)) prepared by using powder metallurgy and microwave sintering method are assessed for their corrosion rate for a period of 28 days. As per the immersion tests results, the addition of ceria nanoparticles to pure Mg, brought about a noteworthy improvement to corrosion resistance. A corrosion rate of approximately 0.84 mm/year for Mg/0.5CeO2 and 0.99 mm/year for Mg/1.0CeO2 nanocomposites were observed. Another aspect of the study involves employing the simulation method i.e. finite element analysis (FEA) to compare the stress distribution in magnesium-ceria nanocomposite based screws and circular bars especially for Mg/0.5CeO2 and Mg/1.0CeO2. Further, the simulation also gives a perception of the impact of masticatory forces, the biting force and shear stress exerted on the Mg/0.5CeO2 and Mg/1.0CeO2 based screws. The simulations results show that the screws showed an acceptable level of stresses for a biting force up to 300 N. The circular bar as well kept its stresses at acceptable levels for the same load of 300N. The shear stress results indicated that a biting force up to 602 N can be safely absorbed by Mg/0.5CeO2 screw. The comprehensive approach allows for a better understanding of the corrosion behavior, stress distribution, and mechanical properties of the Mg/CeO2 nanocomposites, enabling the development of effective temporary implants for craniofacial trauma fixation that can withstand normal physiological forces during mastication. The study reported in this paper aims to target Mg/xCeO2 NCs for temporary implants for craniofacial trauma fixation.

Early outcomes of osteofascial versus osteocutaneous fibula free flap mandibular reconstruction.

BACKGROUND: This study compares early outcomes of osteofascial fibula free flap (OF-FFF) with donor-site primary closure and osteocutaneous (OC) FFF with donor-site skin grafting in segmental mandibular reconstruction. METHODS: A retrospective chart review of FFF mandibular reconstruction patients (2006-2022) divided into OF-FFF and OC-FFF groups. Clinical data, operative parameters, and early postoperative outcomes (≤ 90 days) were analyzed. RESULTS: The study included 67 patients (39 OF-FFF, 28 OC-FFF). OF-FFF had significantly lower donor-site complications (12.8% vs. 53.6%, p < 0.001) and revision surgeries (7.7% vs. 35.7%, p = 0.004) compared to OC-FFF. Recipient-site (28.2% vs. 25%, p = 0.77) and flap (15.4% vs. 17.9%, p > 0.99) complications were comparable. CONCLUSIONS: OF-FFF mandibular reconstruction with donor-site primary closure is a safe and reliable technique associated with superior donor-site and comparable flap and recipient-site outcomes to OC-FFF, thus may be considered as a viable alternative to OC-FFF for selected patients.

Virtual surgical planning for mandibular reconstruction in an abbreviated admission pathway.

OBJECTIVES: Virtual Surgical Planning (VSP) creates individualized surgical plans for free flap reconstruction of mandibular defects. Prior studies indicate that VSP can offer cost benefits due to reduced operative time and length of stay (LOS). We assessed the impact of VSP in the context of a validated postoperative abbreviated LOS clinical pathway. METHODS: This study assessed patients undergoing VSP vs conventional fibular free flap reconstruction for mandibular defects (12/2015-10/2020) and their operative time, ischemia time, and LOS were evaluated. RESULTS: Forty-four patients underwent VSP reconstruction, while 52 patients underwent conventional reconstruction for mandibular defects. VSP was associated with significantly lower total operative time (6 h and 57 mins vs 7 h and 54 mins, p = 0.011), but not length of stay or ischemia time. Total OR time was significantly increased with increasing number of segments needed in both the VSP group (p = 0.002) and the conventional group (p = 0.015). CONCLUSION: Shorter operative times and LOS have been attributed to the use of VSP in free tissue transfers. It is argued that these reductions offset the added cost of VSP. Our study indicates that there is no cost benefit for VSP utilization due to a significantly reduced operative time with no impact on length of admission in an abbreviated admission clinical pathway following free tissue transfer.

Computer-aided designed 3D-printed polymeric scaffolds for personalized reconstruction of maxillary and mandibular defects: a proof-of-concept study.

PURPOSE: To investigate the potential reconstruction of complex maxillofacial defects using computer-aided design 3D-printed polymeric scaffolds by defining the production process, simulating the surgical procedure, and explore the feasibility and reproducibility of the whole algorithm. METHODS: This a preclinical study to investigate feasibility, reproducibility and efficacy of the reconstruction algorithm proposed. It encompassed 3 phases: (1) scaffold production (CAD and 3D-printing in polylactic acid); (2) surgical simulation on cadaver heads (navigation-guided osteotomies and scaffold fixation); (3) assessment of reconstruction (bone and occlusal morphological conformance, symmetry, and mechanical stress tests). RESULTS: Six cadaver heads were dissected. Six types of defects (3 mandibular and 3 maxillary) with different degree of complexity were tested. In all case the reconstruction algorithm could be successfully completed. Bone morphological conformance was optimal while the occlusal one was slightly higher. Mechanical stress tests were good (mean value, 318.6 and 286.4 N for maxillary and mandibular defects, respectively). CONCLUSIONS: Our reconstructive algorithm was feasible and reproducible in a preclinical setting. Functional and aesthetic outcomes were satisfactory independently of the complexity of the defect.

Deep Circumflex Iliac Artery Flap Reconstruction in Brown Class I Defect of the Mandible Using a Three-Component Surgical Template System.

BACKGROUND: Computer-assisted surgery is widely used in mandibular reconstruction, but the process is not well described for cases using the deep circumflex iliac artery flap (DCIA) as the donor site. This study aimed to present a DCIA-based three-component surgical template system (3-STS) in patients with a mandibular Brown class I defect. METHODS: This retrospective cohort study compared clinical outcomes of mandibular reconstruction with DCIA flap using 3-STS or conventional surgical templates. The primary outcome of the study was the accuracy of reconstruction, and the secondary outcomes included surgical time and bone flap ischemia time. Surgery-related parameters and functional outcomes were also recorded and compared. RESULTS: Forty-four patients (23 in the 3-STS group and 21 in the control group) between 2015 and 2021 were included. Compared with the control group, the 3-STS group had higher accuracy of reconstruction, indicated by lower deviation in absolute distance (1.45 ± 0.76 mm versus 2.02 ± 0.89 mm; P = 0.034), and less deviation in coronal and sagittal angles (0.86 ± 0.53 degree versus 1.27 ± 0.59 degrees, P = 0.039; and 2.52 ± 1.00 degrees versus 3.25 ± 1.25 versus, P = 0.047) between preoperative and postoperative computed tomographic imaging. Surgical time and bone flap ischemia time were significantly reduced in the 3-STS group compared with the control group (median time, 385 minutes versus 445 minutes and 32 minutes versus 53 minutes, respectively; P < 0.001). In addition, masseter attachment was preserved in the 3-STS group but not in the control group. No differences were found in adverse events or other clinical variables. CONCLUSION: The 3-STS can improve accuracy, simplify intraoperative procedures to increase surgical efficiency, and preserve functionality in mandibular reconstruction for Brown class I defects. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.