Mandibular reconstruction in children

Survival and infection rates of microvascular free flaps in pediatric mandibular reconstruction: A systematic review and meta-analysis

BACKGROUND

Vascularized free tissue transfer has been established as an effective method in the reconstruction of mandibular defects. However, a limited understanding of its efficacy in pediatric patients persists due to its infrequent presentation. The aim of this study is to systematically consolidate the survival and infection rates of free flaps in pediatric mandibular reconstruction.

METHODS

A systematic literature search was conducted on Ovid Medline, Embase, and Cochrane Library for studies published up to January 2024. We included peer-reviewed studies reporting on survival and infection outcomes associated with free flap mandibular reconstruction in pediatric patients (<18 years). We performed a random-effects meta-analysis with the inverse-variance weighted approach to estimate survival and infection rates. Heterogeneity was assessed by I2, and publication bias was examined using Egger's test.

RESULTS

A total of 26 studies, reporting on 463 free flaps and 439 pediatric patients with a mean age of 10.7 years, were included in our study. Most free flaps originated from the fibula (n = 392/463, 84.7%) and benign tumors were the most common cause for mandibular reconstruction (n = 179/463, 38.7%). The pooled estimate for survival of flaps was 96% (95% CI: 93-97, I2 = 0%), and recipient-site infections were estimated to occur in 9% (95% CI: 6-13, I2 = 0%) of cases. The most common reported complications within the study timeframe were early malocclusion (n = 28/123, 21.4%) and bite abnormalities (18/131, 13.7%).

CONCLUSION

Free tissue transfer for mandibular reconstruction in pediatric patients is effective and safe. Further research is required to explore functionality following mandibular reconstruction in diverse pediatric populations.

Long-Term Update: Free Fibula Flap Growth After Pediatric Mandibular Reconstruction

A free fibular flap is commonly used in adult mandibular reconstruction; however, its use in the pediatric population is not strongly supported. The authors are reporting the long-term update of a case of a pediatric patient who underwent a mandibular reconstruction using a free fibular flap after a resection of mandibular desmoid fibromatosis. Greatest growth was objectively measured and demonstrated at the condyle using a 3-dimensional model generated from Materialise software. This is 1 case and subsequent studies should be observed to further elucidate the full growth potential of the mandible in pediatric patients undergoing mandibular reconstruction.

"Systematic Review and Guidelines for Perioperative Management of Pediatric Patients Undergoing Major Plastic Surgery Procedures, With a Focus on Free Tissue Transfer."

BACKGROUND

Microsurgical free tissue transfer has been successfully implemented for various reconstructive applications in children. The goal of this study was to identify the best available evidence on perioperative management of pediatric patients undergoing free tissue transfer, and use it to develop evidence-based care guidelines.

METHODS

A systematic review was conducted in Pubmed, Embase, Scopus, and Cochrane Library databases. Since a preliminary search of the pediatric microsurgical literature yielded scant data with low level of evidence (LOE), pediatric anesthesia guidelines for healthy children undergoing major surgeries were also included. Exclusion criteria included: vague descriptions of perioperative care, case reports, and studies of syndromic or chronically ill children.

RESULTS

204 articles were identified, and 53 met inclusion criteria. Management approaches specific to the pediatric population were used to formulate recommendations. High quality data was found for anesthesia, analgesia, fluid administration / blood transfusion, and anticoagulation (LOE 1). Lower quality evidence was identified for patient temperature (LOE 3) and vasodilator use (LOE 4). Key recommendations include: administering sevoflurane for general anesthesia, implementing a multimodal analgesia strategy, limiting preoperative fasting, restricting blood transfusions until hemoglobin < 7 g/dl unless patient is symptomatic, and reserving chemical venous thromboembolism prophylaxis for high risk patients.

CONCLUSIONS

Pediatric-specific guidelines are important as they acknowledge physiologic differences in children, which may be overlooked when extrapolating from adult studies. These evidence-based recommendations are a key first step toward standardization of perioperative care of pediatric patients undergoing plastic surgical procedures, including free tissue transfer, to improve outcomes and minimize complications.

Outcomes in Pediatric Maxillofacial Reconstruction With Vascularized Fibular Flaps: A Systematic Review

BACKGROUND

The purpose of this study was to examine the complications and outcomes after maxillofacial reconstruction using the free fibular flap in the pediatric population.

METHODS

A systematic review and descriptive analysis were conducted using data variables, including study characteristics; patient characteristics; postoperative complications (major and minor); surgical revision; and dental rehabilitation.

RESULTS

The systematic review resulted in 1622 articles, 55 of which met inclusion criteria for this study. The 55 articles consisted of 17 case series and 38 case reports with level III/IV and level V of evidence, respectively. Of the 155 identified pediatric patients, the rate of major complications was 13.5% and minor complications was 24.5%. The most common complication was mild growth distortion (n = 7) at the recipient site. Complications at the donor site were less common. During follow-up, 29 patients (18.7%) underwent or awaited surgical revision, and 43 patients (27.7%) underwent or awaited dental rehabilitation.

CONCLUSIONS

Our study suggests that the free fibular flap for pediatric maxillofacial reconstruction is safe and reliable. Additionally, surgical revision to correct the functional impairments resulting from primary reconstruction using the free fibular flap is relatively common.

Pediatric Mandible Reconstruction: Controversies and Considerations

Mandibular reconstruction in pediatric patients has some unique considerations. The method of reconstruction has to factor in the growth potential of the neo-mandible, the native mandible, and the donor site. The condyle is considered the main growth center of the mandible. Current literature indicates that fibula, iliac crest, and scapula osseous flaps do not have the ability to grow. Costochondral grafts exhibit growth because of the costal cartilage component, although the growth is unpredictable. Preservation of the mandibular periosteum can result in spontaneous bone regeneration. Fibula bone harvest in a child mandates close follow-up till skeletal maturity, to monitor for ankle instability and valgus deformity. Dental rehabilitation maintains occlusal relationships, which promotes normal maxillary development. Elective hardware removal should be considered to facilitate future dental implant placement and possible revision procedures. After completion of growth, if occlusion or symmetry is not satisfactory, secondary procedures can be performed, including distraction osteogenesis, orthognathic-type bone sliding operations, and segmental ostectomy.

Outcomes following Microvascular Mandibular Reconstruction in Pediatric Patients and Young Adults

Background:

The etiology and treatment of complex mandibular defects in children differ markedly from those of adults, although treatment with free bone flaps is historical in both groups. While adult outcomes and complication rates are well known, few pediatric data exist, especially for patients with congenital deficiencies. This study reports early and late outcomes from a cohort of young, primarily syndromic patients undergoing microvascular mandibular reconstruction.

Methods:

This is a retrospective case series of patients who underwent microvascular mandibular reconstruction between 1995 and 2016.

Results:

Thirteen patients received a total of 13 fibula transfers and 1 medial femoral condyle transfer. Most patients carried a congenital diagnosis (77%), and the average age during surgery was 11.7 ± 5.7 years. The median (interquartile range) [IQR] length of follow-up was 6.3 (5.7) years. There was a 100% flap survival rate, although 86% of all patients experienced at least one complication. Half of all procedures resulted in an early complication. Nine patients (69%) developed late complications, of which temporal mandibular joint ankylosis was the most common (n = 5; 38%).

Conclusions:

This study is one of few detailing outcomes following mandibular reconstruction by free flap transfer in pediatric patients. These patients were primarily syndromic with appreciable complication rates higher than in other adult and pediatric studies. Some complications are manageable or self-resolving, but others lead to functional problems that may require late operative interventions to correct. Microsurgical treatment should be reserved for children with large, complex mandibular defects when other options are unavailable or have been exhausted.

Quantifying Free Fibula Flap Growth After Pediatric Mandibular Reconstruction

INTRODUCTION

The free fibula flap (FFF) is a preferred option for adult mandibular reconstruction. Due to skeletal immaturity, its routine use in pediatric patients remains in question. Inconsistencies regarding the ability of the FFF to grow in concordance with the patients' natural growth currently exist in the literature. The purpose of this report is to quantify mandibular growth in a young patient undergoing partial hemi-mandibular reconstruction with a FFF utilizing advanced three-dimensional software.

METHODS

A 2-year old underwent left hemi-mandibular reconstruction with a FFF following resection of a desmoid tumor. The condyle was preserved. Using 3D software, changes in mandibular growth and morphology were evaluated based on preoperative (2.1 years old) and postoperative (2.5 years and 5.2 years old) computed tomography imaging.

RESULTS

Mandibular growth occurred throughout the mandible in both postoperative evaluations. Greatest growth was seen in the ramus height. Fibula growth was also seen when comparing measurements to the virtual surgical planning guide. A novel parts comparison analysis revealed the greatest growth potential occurred at the condyle.

CONCLUSION

Providing an objective evaluation using 3D software, we have demonstrated growth throughout the reconstructed mandible, with greatest growth occurring at the preserved condyle. Despite scientific limitations of our study, the potential for mandibular growth appears to remain after FFF reconstruction, offering successful functional and cosmetic outcomes.

Pediatric Mandible Reconstruction for Osteomyelitis During Largest Reported Mycobacterium Abscessus Outbreak

In 2016, water lines at a children's dental clinic in Orange County, California were contaminated with Mycobacterium abscessus (MA), a non-tuberculosis rapidly-growing mycobacterium, leading to the largest MA outbreak ever reported. Mandatory reporting and active case finding directed by the Public Health Department was conducted in collaboration with community Pediatric Infectious Disease physicians for patients who underwent dental pulpotomies at the contaminated Dental Clinic from January 1 to September 6, 2016. Seventy-one cases (22 confirmed and 49 probable) were identified. One case that required extensive debridement and reconstruction of the mandible is presented in detail. CT maxillofacial demonstrated osteomyelitis extending from the right mandibular angle to the left ramus with multifocal periapical lucencies. CT chest and neck revealed numerous pulmonary nodules and bilateral cervical lymphadenopathy. Extraction of several involved teeth, bilateral selective neck dissection, and extensive mandibular debridement was performed, followed by mandibular stabilization with a custom pre-bent 2.0-mm locking plate. CT images 1-year post-operative showed clearance of infection and sufficient bony stability. Subsequent removal of hardware and bone grafting was performed and the patient is doing well. In the event of a future odontogenic mycobacterium outbreak, the experience at our institution can inform multidisciplinary treatment approaches. Prophylactic extraction of primary teeth that received pulpotomies with contaminated water should be performed. Early and thorough debridement of affected bone, including enucleation of secondary teeth, should be performed if necessary for early source control.

Functional and Aesthetic Osseous Free Flap Mandible Reconstruction Using a Low-cost Method: Long-term Results

Mandibular segment loss due to tumoral resection or infectious sequelae causes functional alterations with disorders in mastication, swallowing, speech, and aesthetic alterations with facial asymmetry due to deformity secondary to soft tissue collapse. Reconstructive treatment should recover function and aesthetics. This paper presents a low-cost method of mandibular reconstruction in a series of 6 patients with different years of follow-up (average follow-up time of 11.6 years) using the fibula and scapula free flaps.

Methods

Five female patients and 1 male patient received mandibular reconstruction using osseous free flaps, 5 with the fibula and 1 with the scapula osseous free flap. The patient's ages at the time of surgery ranged from 8 to 62 years (mean 33.1 years). Stainless steel wire was used as the osteosynthesis material, with intermaxillary fixation for 40 days postoperatively and masticatory rehabilitation using mucodental-supported prostheses.

Results

To evaluate the aesthetic result and the facial symmetry, a questionnaire and the photographs of all the cases were sent to 8 plastic surgeons. The functional result was evaluated in 5 of the 6 patients using the Spanish version of the Oral Health Impact Profile. All flaps survived, dental occlusion was achieved in all patients, no tumors recurred, masticatory function was normal without swallowing or speech alterations, and the transplanted bone hypertrophied and spontaneously remodeled, providing facial symmetry with good aesthetic results.

Conclusion

We present a low-cost and universally applicable mandibular reconstruction method, with long-term follow-up and good aesthetic and functional results.

Osseous Changes Over Time in Free Fibular Flap Reconstruction

OBJECTIVES/HYPOTHESIS

Evaluate bone resorption in free fibular grafts and document resorption behavior as compared to dentulous and edentulous autochthonous mandibular bone.

STUDY DESIGN

Retrospective Chart review.

METHODS

Postoperative computed tomography images were used to evaluate fibular graft resorption rates and corresponding sites of the dentulous or edentulous mandible. Bone height, width, and cortical thickness were measured.

RESULTS

Eighteen patients underwent fibula free flap reconstruction following resection of a primary head and neck cancer. Mandibular defects were classified using Jewer's classification. The average interval loss of osseous height was 0.23 ± 0.09 mm/yr for fibula flap, 0.55 ± 0.13 mm/yr for dentulous native mandible, and 0.98 ± 0.41 mm/yr in edentulous native mandible. Change in osseous width was 0.19 ± 0.08 mm/yr, 0.55 ± 0.33 mm/yr, and 0.73 ± 0.15 mm/yr, respectively. Rate of superior cortical resorption was 0.33 ± 0.34 mm/yr, 0.35 ± 0.13 mm/yr, and 0.53 ± 0.11 mm/yr in fibula flap, dentulous, and edentulous mandible, respectively. Inferior cortical resorption rates were quantified as 0.30 ± 0.11 mm/yr, 0.35 ± 0.08 mm/yr, and 0.51 ± 0.08 mm/yr.

CONCLUSIONS

Fibula free flap reconstruction of the mandible provides excellent functional results and allows for stable outcomes. Bone resorption is significantly lower in fibular graft compared with both edentulous and dentulous mandible. Edentulous bone displays significantly increased rates of atrophy in comparison to the dentulous mandible. This may have implications with regard to long-term viability of both the fibular flap and native mandible. The role of dental restoration on overall osseous stability warrants further research.

LEVEL OF EVIDENCE

4 Laryngoscope, 129:1113-1116, 2019.

Bone regeneration and docking site healing after bone transport distraction osteogenesis in the canine mandible

PURPOSE

Bone transport distraction osteogenesis provides a promising alternative to traditional grafting techniques. However, existing bone transport distraction osteogenesis devices have many limitations. The purpose of this research was to test a new device, the mandibular bone transport reconstruction plate, in an animal model with comparable mandible size to humans and to histologically and mechanically examine the regenerate bone.

MATERIALS AND METHODS

Eleven adult foxhounds were divided into an unreconstructed control group of 5 animals and an experimental group of 6 animals. In each animal, a 34-mm segmental defect was created in the mandible. The defect was reconstructed with a bone transport reconstruction plate. Histologic and biomechanical characteristics of the regenerate and unrepaired defect were analyzed and compared with bone on the contralateral side of the mandible after 4 weeks of consolidation.

RESULTS

The reconstructed defect was bridged with new bone, with little bone in the control defect. Regenerate density and microhardness were 22.3% and 42.6%, respectively, lower than the contralateral normal bone. Likewise, the anisotropy of the experimental group was statistically lower than in the contralateral bone. Half the experimental animals showed nonunion at the docking site.

CONCLUSION

The device was very stable and easy to install and activate. After 1 month of consolidation, the defect was bridged with new bone, with evidence of active bone formation. Regenerate bone was less mature than the control bone. Studies are underway to identify when the regenerate properties compare with normal bone and to identify methods to augment bone union at the docking site.

Reconstruction of canine mandibular bone defects using a bone transport reconstruction plate

OBJECTIVES

Reconstruction of mandibular segmental bone defects is a challenging task. This study tests a new device used for reconstructing mandibular defects based on the principle of bone transport distraction osteogenesis.

METHODS

Thirteen beagle dogs were divided into control and experimental groups. In all animals, a 3-cm defect was created on one side of the mandible. In 8 control animals, the defect was stabilized with a reconstruction plate without further reconstruction and the animals were killed 2 to 3 months after surgery. The remaining 5 animals were reconstructed with a bone transport reconstruction plate, comprising a reconstruction plate with attached intraoral transport unit, and were killed after 1 month of consolidation.

RESULTS

Clinical evaluation, cone-beam CT densitometry, three-dimensional histomorphometry, and docking site histology revealed significant new bone formation within the defect in the distracted group.

CONCLUSION

The physical dimensions and architectural parameters of the new bone were comparable to the contralateral normal bone. Bone union at the docking site remains a problem.

Reconstruction of large mandibular bone and soft-tissue defect using bone transport distraction osteogenesis

Reconstruction of large anterior mandibular defects is a challenging task. The condition can become even more complex if primary reconstruction fails, leading to loss of the entire midline portion of the lower face with massive scarring of the remaining tissues. Bone transport distraction osteogenesis can provide a viable treatment option for these patients. One of such cases will be presented, followed by a discussion of the advantages, disadvantages, and limitations of the technique.

Stereomodel-Assisted Fibula Flap Harvest and Mandibular Reconstruction

PURPOSE

To describe a method for stereomodel-assisted fibula flap harvest and mandibular reconstruction utilizing multiple fibula bony segments.

MATERIALS AND METHODS

Stereomodels of the mandible and the fibula were obtained from computed tomography scan data. The length of fibula to be harvested was predetermined by measurement of the stimulated of existing mandibular defect on the mandibular stereomodel. A titanium reconstruction plate was shaped to fit the original mandibular contour. The stereomodel fibula was divided into multiple segments and the segments were placed on the mandibular stereomodel in the ideal edentulous position against the upper dentition and simulate the angular contour of the mandible for best comesis. The predetermined bony segments were measured and the system was then transferred to the patient in the operation theater using acrylic locating splints.

RESULTS

Experience with 8 patients (2 primary and 2 secondary reconstructions) indicated that a good clinical outcome in terms of mandibular contour and positions of the reconstructed segment was possible. The outer facial appearance and symmetry were consistently excellent and no instability or malposition of the graft segments was encountered.

CONCLUSION

Stereomodel-assisted fibula flap harvest and insertion is a worthwhile attempt at improving the results of mandibular reconstruction and deserves further attention.

Atrophy of Free Fibular Grafts after Mandibular Reconstruction

BACKGROUND

In free fibular flap surgery, the graft's low vertical height and tendency to resorb over time have been considered potential drawbacks. This study investigated (1) short- and long-term bone resorption in free fibular grafts; (2) resorption behavior of fibular grafts versus dentulous and edentulous autochthonous mandibular bone; and (3) factors that potentially influence long-term bone atrophy, such as site of reconstruction, presence of osseointegrated dental implants, patient age, and adjuvant radiation therapy.

METHODS

Between 1992 and 2004, 113 patients received free fibular grafts. Fifty-four of these patients were examined retrospectively. Postoperative Panorex examinations assessed loss of bone height per month. Standardized miniplate measurements served as a reference to prevent errors caused by projection on magnification.

RESULTS

Follow-up ranged from 6 months to 12 years. According to Jewer's classification, the following defect types were found: L, 23 (42.6 percent); H, five (9.3 percent); C, two (3.7 percent); LC, 12 (22.2 percent); HC, nine (16.7 percent); and LCL, three (5.6 percent). Radiographic analysis revealed a monthly atrophy of 0.04 +/- 0.08 mm (mean +/- SD) for fibular bone, 0.14 +/- 0.11 mm for dentulous mandibula, and 0.20 +/- 0.17 mm for edentulous mandibula. The difference in bone loss between fibula and edentulous or dentulous bone was significant (Friedman's test and Wilcoxon paired-sample test, p < 0.0001 and p = 0.02, respectively). Investigated factors had no significant influence on bone resorption rate.

CONCLUSIONS

Fibular grafts show short- and long-term stability. Their rate of atrophy is significantly lower than that of edentulous or dentulous mandibular bone. Thus, implants can be inserted into this bone graft just as successfully as they are inserted into adjacent mandibular bone when the same bone height is present.

Complications of mandibular reconstruction in childhood: Report of a case of Juvenile Aggressive Fibromatosis

Juvenile aggressive fibromatosis is an acquired disease affecting young children. There are two types: superficial and deep; the first is not aggressive whilst the second invades other tissues deeply. This is a case report of the deep variant of juvenile aggressive fibromatosis of the lateral mandible affecting a 24-month-old young female patient. The tumour has been treated surgically by resection of the mandible and reconstruction with a rib-graft. To by-passs resorption of the rib-graft and to re-establish the correct three-dimensional shape of the facial skeleton, osteodistraction of the reconstructed mandible was performed six months post-peratively. In this article the surgical techniques to reconstruct the mandible in young children are discussed.

Mandibular Growth following Reconstruction Using a Free Fibula Graft in the Pediatric Facial Skeleton

BACKGROUND

Mandible reconstruction in the growing facial skeleton is challenging, especially with reconstructions necessitating free vascularized bone grafts. The need for further combined orthodontic-orthognathic intervention at skeletal maturity must be anticipated. The growth potential of these grafts and potential new problems associated with performing a sagittal split osteotomy at skeletal maturity are poorly understood.

METHODS

A retrospective chart review revealed 11 patients who underwent reconstruction with a free fibula at The Hospital for Sick Children from 1990 to 2000. Radiographic and photographic studies were assessed for long-term growth of the reconstructed mandible, with follow-up ranging from 2 to 12 years.

RESULTS

Of the 11 patients who underwent reconstruction with a free fibula, two had surgery at skeletal maturity, two moved out of the country, one died as a result of her malignancy, and one was lost to follow-up. The remaining five patients are being followed by the craniofacial and orthodontic services and have not reached skeletal maturity. Of the two patients who have had orthognathic surgery, the one patient whose reconstruction involved the temporomandibular joint exhibited no growth on the reconstructed side and required a 57-mm advancement on the reconstructed side. The other patient, who had preservation of the temporomandibular joint at the time of reconstruction, required only a 5-mm advancement on the reconstructed side. Both patients had significant surgical complications as a result of the initial reconstructive techniques. Technical modifications necessary at the initial reconstruction became apparent when the authors performed a sagittal split osteotomy on the reconstructed side.

CONCLUSIONS

Certain technical modifications to the original free fibula reconstructed pediatric mandible should be considered in anticipation of the need for a subsequent bilateral sagittal split at skeletal maturity.

[Free fibula transfer. Analysis of 76 consecutive microsurgical procedures and review of the literature]

Since its introduction by Taylor in 1975, microvascular free fibula transfer has become the gold standard in osseous reconstructions requiring vascularized bone transfer. Various modifications of the free fibula have been described in the literature. We reviewed a series of 76 free vascularized fibula transfers during a 7-year period. Data was retrospectively analyzed with respect to type of procedure and outcome, general surgical complications, and flap-related (specific) complications. Of all 76 free fibula flaps, 47 cases healed uneventfully (62%). Interestingly, 53% of all extremity reconstruction cases had at least one of the above complications, whereas in maxillofacial cases the complication rate was only 25%. Complete osseous consolidation at the time of evaluation was confirmed in 58 patients (76%). Complete flap failure occurred in four patients (5%). The complication rates reflect the complexity of the procedures and appear strongly related to the underlying disease and predisposing medical risk factors. Time will tell if advances, e.g., in the field of tissue engineering, will eventually replace autologous vascularized bone transfer.

Long-term radiological findings following reconstruction of the condyle with fibular free flaps

AIM

Fibular bone grafts are considered as one of the best choices for reconstruction of the condyle. However, little data are available on bone remodelling after such reconstruction. The purpose of this study was to evaluate the long-term radiological outcome.

PATIENTS AND METHODS

Eleven patients underwent condylar reconstruction with a free fibular transplant. In all cases the end of the fibular graft was placed into the glenoid fossa under the intact temporomandibular joint (TMJ) disc. Evaluation consisted of digital width and length measurement of the end of the fibula on panorex studies.

RESULTS

Remodelling of the end of the neocondyle was found and consisted of rounding off and narrowing of the end of the transplant.

CONCLUSION

The most likely explanation for these changes is the fact that the TMJ disc was preserved.