Outcomes following Microvascular Mandibular Reconstruction in Pediatric Patients and Young Adults

Review of the Literature on the Current State of Periosteum-Mediated Craniofacial Bone Regeneration

Study Design

This is an article review on the current state of periosteum-mediated bone regeneration (PMBR). It is a known mandibular reconstruction option in children, and though poorly understood and unpredictable, the concerns of developmental changes to donor and recipient tissues shared by other treatment options are nonexistent. The definitive role of periosteum during bone regeneration remains largely unknown.

Objective

The objective is to review the literature on the clinical and molecular mechanism evidence of this event.

Methods

Our search methodology was modeled after the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) guidelines. Search strategies were categorized into search 1 for clinical evidence of mandibular regeneration and search 2 for gene expression review for craniofacial regeneration. The quality assessment of each publication was undertaken, and inclusion criteria comprise mandibular continuity defect for search 1 and use of gene expression assay propriety kit for search 2.

Results

33 studies were selected for search 1 while four studies with non-human subjects were selected for search 2. Monitoring of PMBR onset was advised at 2 weeks post-operative, and the gene expression results showed an upregulation of genes responsible for angiogenesis, cytokine activities, and immune-inflammatory response in week 1 and skeletal development and signaling pathways in week 2.

Conclusions

The results suggest that young periosteum has a higher probability of PMBR than adult periosteum, and skeletal morphogenesis regulated by skeletal developmental genes and pathways may characterize the gene expression patterns of PMBR.

Does Free Fibular Flap Reconstruction Affect the Quality of Life in Pediatric Patients With Various Extend of Mandible Defects?

BACKGROUND

The long-term outcomes in pediatric patients with various extents of mandible defects have not been well-documented.

METHODS

A retrospective case series in which this study looked at pediatric patients under the age of 13 who had mandibular reconstruction with free fibular flap and had not received another operation in the previous 6 months. The eating, swallowing, speech function, and quality of life are evaluated with EORTC QLQ-H&N35 after the mandible growth spurt has occurred.

RESULTS

A total of 7 patients were included in this study with operation ages ranging from 6 years 1 month to 12 years 2 months. The etiology of malignant tumors was found in 2 patients and benign tumors in 5 patients. The mandibular defect distribution consists of 1 class Ic, 1 class II, 2 class IIc, 2 class III, and 1 class IVc. All patients reported no swallowing or speech difficulties. However, transient eating trouble was seen in 1 patient due to the extensive defect size that causes tooth loss. Only 1 patient received dental rehabilitation. The patients displayed an overall good quality of life with an average score of 2.857.

CONCLUSIONS

Free fibular flap for mandibular reconstruction in children who have not reached their mandibular growth peak have a satisfying outcome, both in their function and quality of life.

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.

Genetic determinants of periosteum-mediated craniofacial bone regeneration: a systematic review

BACKGROUND

Periosteum-mediated bone regeneration (PMBR) is a recognized method for mandibular reconstruction. Despite its unpredictable nature and the limited degree to which it is understood, it does not share the concerns of developmental changes to donor and recipient tissues that other treatment options do. The definitive role of the periosteum in bone regeneration in any mammal remains largely unexplored. The purpose of this study was to identify the genetic determinants of PMBR in mammals through a systematic review.

METHODS

Our search methodology was designed in accordance with the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) guidelines. We conducted a quality assessment of each publication, and evaluated the differences in gene expression between days 7 and 15.

RESULTS

A total of four studies satisfied the inclusion criteria. The subjects and tissues examined in these studies were Wistar rat calvaria in two studies, mini-pigs in one study, and calves and mice in one study. Three out of the four studies achieved the necessary quality score of ≥ 3. Gene expression analysis showed increased activity of genes responsible for angiogenesis, cytokine activities, and immune-inflammatory responses on day 7. Additionally, genes related to skeletal development and signaling pathways were upregulated on day 15. Conclusions: The results suggest that skeletal morphogenesis is regulated by genes associated with skeletal development, and the gene expression patterns of PMBR may be characterized by specific pathways.

Pediatric Mandibular Reconstruction With Free Serratus Anterior-Rib Composite Flap: A Case Report

ABSTRACT

Reconstruction of children's mandibles after mandibular resection for benign or malignant tumors is challenging. Microvascular flap reconstruction is a common treatment option for restoring mandibular continuity after the resection of oral cavity neoplasms.We presented 2 cases of childhood mandibular reconstruction after tumor wide excision and segmental mandibulectomy, one for malignant cancer and one for benign ossifying fibroma, with serratus-rib composite free flap. All 2 patients had a favorable facial profile, functional outcome, and dental occlusion at the last follow-up. The development of children's mandible and donor site needs to be considered compared with adult's mandibular reconstruction. Given its reliability and utility, this flap can be an alternative for pediatric mandibular reconstruction compared with the free fibular flap and other candidates.

Microsurgical reconstruction of the enormous traumatic oromandibular defect by osteocutaneous fibula-free flap in a 9-year-old child: a case report

Enormous oromandibular defects in children remain a reconstructive challenge due to the region's unique features and the scarcity of a perfectly matched recipient site. The osteocutaneous fibula-free flap (OCFFF) is an excellent option for these defects. Most reports on oromandibular reconstruction in children are limited to surgical techniques instead of long-term follow-up, especially in resource-limited settings. We reported a 9-year-old child who presented with a massive oromandibular defect caused by a high-energy gunshot. Firstly, the patient was treated with debridement, lower defect edges approximation, and tracheostomy. After one week, the procedure of OCFFF was performed, and two months later, the lower lip was reconstructed using a tongue flap. The aesthetic outcome was excellent at two years, and the patient could speak and eat without impaired oral function. In conclusion, microsurgical reconstruction using OCFFF for massive oromandibular defects in our child patient was safe with satisfactory facial aesthetics and oral function.

Congenital Mandibular Hypoplasia: Patient-Specific Total Joint Replacement as a Line Extension in the Treatment of Complex Craniofacial Anomalies

Introduction

Congenital mandibular hypoplasia (CMH) remains challenging because of the underlying combined hard and soft tissue deficiency. Treatment options include craniofacial distraction, orthognathic surgery, and autologous grafts, although the latter produces inadequate results after distraction and autologous grafting. Unsatisfactory long-term stability may cause relapse, necessitating reoperation.

Material and Methods

We investigated the feasibility of using alloplastic total joint replacement (TJR) in growing and young adult CMH patients. The primary outcome was long-term reconstruction stability, without implant failure. Secondary outcomes were TMJ function and pain, and jaw movements achieved during surgery.

Results

Three patients (age: 9–22 years) were treated by the same surgeon at one institution during 2018–2021. Anamnesis and clinical parameters were obtained from patient records. Preoperative 3D-scans were superimposed with postoperative 3D-scans and preoperative plans, including TJR-implant STL files, to measure jaw movement. All patients underwent prior reconstructive surgery. Mandibular movement of 16.4–20.1 mm in the sagittal direction was achieved. Post-TJR follow-up ranged from 24 to 42 months. No long-term complications occurred. At the latest follow-up, the maximal interincisal opening was between 21 and 40 mm, and all implants were functioning, without failure.

Conclusion

In selected CMH cases, alloplastic TJR can deliver satisfactory medium-term results with predictable and stable outcomes, even in growing patients.