Use of a Fibula Free Flap for Mandibular Reconstruction in Severe Craniofacial Microsomia in Children with Obstructive Sleep Apnea

Surgical Innovation in Serial Reconstruction of Micrognathia Using Free Fibular Flap: Insights From a Study and Literature Review

BACKGROUND

Free fibular flap (FFF) is the main modality in the reconstruction of maxillofacial defects. Micrognathia is a condition where the mandible is smaller than it should be. Micrognathia is typically treated with mandibular distraction osteogenesis, bilateral sagittal split osteotomy, and conventional costochondral graft. In cases in which these procedures cannot be performed, FFF becomes a suitable alternative. Publications regarding the use of FFF in cases of micrognathia are currently still limited. In this case, we present the use of FFF in the reconstruction of a severely micrognathic mandible in an adult patient.

CASE PRESENTATION

A 28-year-old woman with micrognathia was referred to Dr. Ciptomangunkusumo Hospital for reconstruction. The patient had previously undergone temporomandibular joint (TMJ) reconstruction surgery with interpositional TMJ arthroplasty 10 years prior due to an ankylosing TMJ that prevented the opening of the jaw. The treatment for ankylosing TMJ was necessitated due to the patient's inability to open their mouth, resulting in significant challenges with alimentation, speech, and facial morphology. Here the authors reported mandibular lengthening reconstruction in the anteroposterior axis with FFF. A surgical osteotomy was performed on the posterior segment of the bilateral mandibular ramus, then the segmented fibula was inserted into the resulting defect. Flap refinement was also performed following FFF. Postsurgical evaluation revealed notable enhancements in the patient's esthetic appearance, occlusal function, and amelioration of obstructive sleep apnea symptoms.

CONCLUSIONS

FFF for mandibular reconstruction is feasible and effective in improving esthetic and functional outcomes in patients with micrognathia.

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.

3D-CT measurements of facial symmetry in severe CFM patients: A comparative study between mandibular ascending ramus distraction osteogenesis and bone grafting

This study aims to compare the effects of mandibular distraction osteogenesis (MDO) and bone grafting on the facial symmetry of children with Pruzansky-Kaban type IIB and III craniofacial microsomia (CFM). Medical records and three-dimensional computed tomography (3D-CT) data of CFM patients who had primarily undergone MDO and bone grafting were collected. A retrospective analysis of pre-and post-operative 3D imaging data was conducted to compare the improvement rate in facial symmetry between the two groups based on occlusal cant, affected/unaffected ramus height ratio and chin point deviation. The data were tested for normality using the Shapiro-Wilk test. When the data followed a normal distribution, a paired sample t-test was employed for the comparison between preoperative and postoperative data. When the data did not follow a normal distribution, the Wilcoxon signed-rank test for paired samples was used for preoperative and postoperative comparison. The study included 18 children with type IIB and III CFM, 11 in the MDO group and 7 in the bone grafting group. In the MDO group, postoperative Gn-FH and Gn-Cor distances increased significantly, whereas the postoperative Gn-Mid distance decreased significantly. Occlusal cant decreased significantly and ramus height affected/unaffected ratio increased significantly after MDO. In the bone graft group, there was no statistically significant difference in the postoperative ratios of chin deviation, occlusal cant, and ramus height affected/unaffected compared to the preoperative values. Compared to bone grafting, MDO can significantly enhance ramus height ratio, level occlusal plane, and centralize the chin point among patients with CFM. Furthermore, MDO achieves superior enhancements in facial symmetry.

Influence of microvascular mandibular bony reconstruction on the posterior airway space: A retrospective cohort study

INTRODUCTION

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.

MATERIALS AND METHODS

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.

RESULTS

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.

CONCLUSIONS

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.