Improved Mandible Function After Hemimandibulectomy, Condylar Head Preservation, and Vascularized Fibular Reconstruction

Osteo-cutaneous microvascular free-flaps are a viable option for reconstructing the temporomandibular joint

Background

There are multiple reconstructive options after mandibular resection and disarticulation of the condyle. The purpose of this study was to assess the clinical outcomes and functionality of osteocutaneous free flaps in the reconstruction of mandibular defects that involve the Temporo-Mandibular Joint (TMJ).

Methods

Our study is a retrospective cohort study involving subjects who underwent mandibular resection and needed TMJ reconstruction with vascularized bony-free flaps from February 2016 to June 2018. Data gathered included patient demographics, post-operative function, maximum interincisal opening (MIO), occlusion status, deviation on opening, and TMJ symptoms. Data points collected from postoperative CT imaging included the following: position of the flap in relation to the glenoid fossa and articular eminence, and closest point of contact.

Results

Eight out of the nine patients who underwent free flap reconstruction of mandibular defects involving the TMJ qualified for the study. The mean age was 39.7 years old. In all 8 cases, virtual surgical planning (VSP) was used. The mean follow-up time was 18.75 months. The flap success rate was 100%. The mean MIO was 37.37 mm. Six patients resumed their premorbid diet, and one patient developed dysphagia and was peg tube dependent. In seven cases the occlusion was intact and reproducible, one case was without sufficient teeth for occlusion. On imaging, the mean distance from the neo-condyle to the glenoid fossa was 14 mm and to the articular eminence 8.68 mm. The point of closest contact in all cases appeared to be the articular eminence.

Conclusion

Vascularized Osteocutaneous-flaps such as FFFs and DCIA flaps provide a good option for the reconstruction of mandibular defects that involve the TMJ. Ipsilateral deviation on opening does not negatively affect clinical outcomes or function. Placing patients in Maxillomandibular fixation for 4-6 weeks may help to prevent condylar sag and provide stable post-operative occlusion.

How Is a Cutting Guide With Additional Anatomical References Better in Fibular-Free Flap Mandibular Reconstruction? A Technical Strategy

BACKGROUND

Computer-assisted surgery is used to design and manufacture cutting guides in mandibular reconstructions with fibula-free flaps. To improve the outcomes of the procedure, the aim of this research was to investigate and compare the accuracy of mandibular reconstruction following the use of 2 versus 3 anatomical reference cutting guides.

METHODS

Eighteen sets of prototype bone models retrieved from an ameloblastoma patient were used for mock operations. The mandibular segmental osteotomies and fibular reconstructions were performed using 2 and 3 anatomical reference cutting guides in vivo surgeries. After reconstruction, the accuracy of the placed reference points was measured by superimposition of computed tomography images.

RESULTS

The error in cutting guides when using 2 or 3 anatomical references showed no significant difference. The fibular and condylar errors of the cutting guide between 2 and 3 anatomical references showed no significant difference in every plate type. The difference in screw hole position errors between 2 and 3 anatomical reference cutting guides was not statistically significant.

CONCLUSIONS

Two anatomical reference cutting guides are sufficient and reasonable enough for mandible resection. However, there were some limitations and errors in our study.

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.

Changes in condylar position and morphology after mandibular reconstruction by vascularized fibular free flap with condyle preservation

OBJECTS

Changes in condylar position and morphology after mandibular reconstruction are important to aesthetic and functional rehabilitation. We evaluated changes in condylar position and morphology at different stages after mandibular reconstruction using vascularized fibular free flap with condyle preservation.

MATERIALS AND METHODS

A total of 23 patients who underwent mandibular reconstruction with fibular flap were included in this retrospective study. CT data of all patients were recorded before surgery (T0), 7 to 14 days after surgery (T1), and at least 6 months after surgery (T2). Five parameters describing the condylar position and 4 parameters describing the morphology were measured in sagittal and coronal views of CT images. The association between clinical characteristics and changes in condylar position and morphology was analyzed. A finite element model was established to investigate the stress distribution and to predict the spatial movement tendency of the condyle after reconstruction surgery.

RESULTS

The condylar position changed over time after mandibular reconstruction. The ipsilateral condyles moved inferiorly after surgery (T0 to T1) and continually move anteriorly, inferiorly, and laterally during long-term follow-up (T1 to T2). Contrary changes were noted in the contralateral condyles with no statistical significance. No morphological changes were detected. The relationship between clinical characteristics and changes in condylar position and morphology was not statistically significant. A consistent result was observed in the finite element analysis.

CONCLUSION

Condylar positions showed obvious changes over time after mandibular reconstruction with condylar preservation. Nevertheless, further studies should be conducted to evaluate the clinical function outcomes and condylar position.

CLINICAL RELEVANCE

These findings can form the basis for the evaluation of short-term and long-term changes in condylar position and morphology among patients who have previously undergone mandibular reconstruction by FFF with condyle preservation.

An Artificial Intelligence-Based Cosmesis Evaluation for Temporomandibular Joint Reconstruction

OBJECTIVE

Management of the temporomandibular joint (TMJ) following condylar resection remains challenging in the field of mandibular reconstruction. A simple reconstruction of the TMJ with a contoured end of a fibular graft placed into the joint space is a potential option, but its efficacy is unknown partly because there are only few objective assessment systems for aesthetic outcome. This study aimed to develop an artificial intelligence (AI)-based aesthetic outcome evaluation system for the simple TMJ reconstruction method and evaluate its functional outcomes.

METHODS

Patients who underwent segmental mandibular resection and reconstruction with fibular flaps at our institution between 2011 and 2020 were retrospectively reviewed. The mandibular asymmetry value was introduced as a primary aesthetic outcome measure, calculated for each patient's photograph using facial recognition AI. The outcomes of the simple TMJ reconstruction method were compared with those of cases in which the native condyle was preserved.

RESULTS

Ten patients underwent condylar resection followed by simple TMJ reconstruction, while the native condyle was preserved in 18 patients. No significant difference was observed in the postoperative mandibular asymmetry value between the two treatment groups. No significant differences were found in the functional outcomes of deglutition and speech.

CONCLUSION

The AI-based asymmetry evaluation system was useful as an aesthetic outcome measure in mandibular reconstruction. Simple TMJ reconstruction with a fibular end seemed to be a promising option, as there were no significant differences in both aesthetic and functional outcomes between this method and those cases in which the native condyle was preserved. Laryngoscope, 133:841-848, 2023.

Three dimensional condylar positional and morphological changes following mandibular reconstruction based on CBCT analysis: a prospective study

OBJECTIVE

This study aimed to evaluate the condylar positional changes following mandibular reconstruction with preservation of the condylar head using Cone-Beam Computed Tomography (CBCT). Also, to assess joint space changes and the overall volumetric space compared to the preoperative status.

METHODOLOGY

This prospective study included 30 patients (60 joints) subjected to unilateral mandibular resection and reconstruction with preservation of the condylar head. The Helkimo index and preoperative (T1), two weeks postoperative (T2), and follow-up CBCTs (T3) after at least six months were gathered and processed to evaluate the condylar position and TMJ joint space using Anatomage Invivo 6. A student's t-test and repeated-measures ANOVA statistics were used. A P value of less than 0.05 was considered statistically significant.

RESULTS

Thirty patients (14 males, 16 females) with a mean age of 40.01 ± 12.7 years (a range of 18.1-62.9 years) were included. On the tumor side, there were significant variances in the vertical and mediolateral condylar positions between the three-time points (T1, T2, T3). Immediately after the operation, the condyles were significantly displaced in a downward direction at T2, which became larger after the last follow-up period (T3) (p = 0.007). The condylar positions at the anteroposterior direction were relatively stable without significant differences between the three times points (p = 0.915). On the non-tumor side, the condylar positions were relatively stable in the mediolateral and anteroposterior positions. In the tumor side, all of the TMJ spaces were significantly increased in size following the mandibular reconstructions (T2 and T3). However, on the non-tumor side, the anterior, posterior, and medial joint spaces were significantly changed postoperatively.

CONCLUSION

After mandibular reconstruction with condylar preservation, the condylar position and volumetric measurement immediately changed noticeably and continued to be a permanent change over time compared to relatively stable condyles on the non-tumor side. According to Helkimo index, patients become adapted to the postoperative changes without significant differences between the two sides.

The value of prebent reconstruction plates and in-house 3D printing

INTRODUCTION

Reconstruction plates, prebent on 3D printed models, are a cheap, quick, and safe solution to improve mandibular reconstruction procedures. The European Medical Device Regulation has changed recently and severely affects 3D printing in hospitals. Therefore, its legitimation must be discussed. This retrospective observational Case-Control Study aimed to evaluate the impact of prebent reconstruction plates on the condylar position in the temporomandibular joint after continuity resection of the mandible in oncological cases.

MATERIALS AND METHODS

We included patients who underwent segmental mandibular resection without exarticulation of the condyle or history of prior surgery. The patients were divided into groups with prebent plates on a stereolithographic model and intraoperatively bent reconstruction plates. The segmental defects were categorized using the Jewer Classification. Computed Tomography (CT) scans before and after surgery were analyzed using a standardized method to measure the metric movement of the condyles, as well as their angulation to reference planes to quantify positional changes (primary outcome measures). The influence of the defect location, according to the Jewer classification, was evaluated as a secondary outcome measure.

RESULTS

73 patients, including 33 with preformed reconstruction plates, were included. We could show significantly fewer rotational deviations in cases of prefabricated osteosynthesis in the coronal plane (p<0,001) and in the sagittal plane (p<0,027).

DISCUSSION

Using preformed reconstruction plates on 3D printed models improves the correct anatomical position of the condyle after mandibular resection. Especially Jewer-class-L defects seem to benefit from individualized reconstruction plates.

The Precision of Different Types of Plates Fabricated With a Computer-Aided Design and Manufacturing System in Mandibular Reconstruction With Fibular-Free Flaps

Computer-assisted surgery (CAS) has been introduced to mandible reconstruction with fibular-free flap in cutting guide placement. When CAS cooperates with different plate fixations, the results show various degrees of errors by which this study aimed to evaluate. Mock surgeries were conducted in 3D-printed mandibles with 2 types of defects, limited or extensive, reconstructed from 2 ameloblastoma patients. Three types of fixations, miniplate, manually bending reconstruction plate, and patient-specific plate, are tested, each of which was performed 3 times in each type of defect, adding up to 18 surgeries. One with the least errors was selected and applied to patients whose 3D-printed mandibles were derived. Finally, in vivo errors were compared with the mock. In limited defect, average errors show no statistical significance among all types. In extensive defect, patient-specific plate had a significantly lower average condylar error than manually bending reconstruction plate and miniplate (8.09±2.52 mm vs. 25.49±2.72 and 23.13±13.54 mm, respectively). When patient-specific plate was applied in vivo , the errors were not significantly different from the mock. Patient-specific plates that cooperated with CAS showed the least errors. Nevertheless, manually bent reconstruction plates and miniplates could be applied in limited defects with caution.

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.

Short ramus reconstruction for hemi-mandibulectomy defect: Case reports

Reconstruction of the mandible following hemimandibulectomy is difficult and complex.

The appropriate approach to condylar reconstruction remains controversial. In this report, the authors propose the concept of “short ramus reconstruction” after hemimandibulectomy. In this technique, a neocondyle is constructed around the base of the condyle to avoid trismus and ankylosis. Four patients underwent short condylar reconstruction using fibula free flaps. Post-surgery, no patient developed trismus or ankylosis. Centric occlusion, good masticatory function, and favourable aesthetic outcomes were achieved in all cases. “Short ramus reconstruction” is a simple and convenient method to reconstruct the mandible following hemimandibulectomy.

Patient specific implant with high condylar neck osteotomy for temporomandibular joint preservation in segmental mandibulectomy

STUDY DESIGN

Letter to the Editor.

OBJECTIVE

Disarticulation may be considered during segmental mandibulectomy where margins necessitate high condylar neck osteotomy. Although a number of techniques have been reported for reconstruction of the condyle, successful preservation of normal joint anatomy, where possible, should be considered as a superior alternative. This report demonstrates a safe and predictable approach to condylar head preservation with high condylar neck osteotomy.

METHODS

We present two cases of native TMJ preservation with a very short salvageable condylar component utilising 3D-printed patient specific cutting guides and implants.

RESULTS

The condyle preserving reconstructive technique described successfully preserves the capsule of the TMJ, and with careful execution can preserve the intra-articular components of the joint and their relationships to each other. Both patients have experienced excellent outcomes to date.

CONCLUSIONS

As opposed to disarticulation reconstructions, this technique is more likely to achieve long-term normal occlusion, maintain normal alignment of reconstructed segments, and preserve condylar translation as opposed to simple hinging, in addition to avoiding the potential pitfalls of alternative techniques.

Objectifying growth of vascularized bone transfers after mandibular reconstruction in the pediatric population

BACKGROUND

Autologous vascularized bone transfer is the preferred strategy for the reconstruction of mandibular defects in a pediatric population. The principal argument is the theoretical postoperative growth potential of the neomandible, which uses vascularized donor tissues.

OBJECTIVES

The purpose of this study was to objectify the veritable growth potential of vascularized bone transfers in children.

METHODS

A literature search was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, revealing 57 patients younger than or equal to 18 years who had undergone a mandibular reconstruction with a vascularized free flap. Only studies using postoperative imaging were included. Outcomes regarding growth and postoperative corrections and complications were analyzed.

RESULTS

Neomandibular growth was observed in 63.2% of all included patients. The proportion of growth was higher in patients with condylar preservation (95.7%) than that of patients with condylar involvement (41.2%). Reconstruction of the condyle by a free flap, which includes an epiphyseal growth plate or cartilage increased postoperative growth potential (77.8%) but did not reduce the need for later orthognathic surgery.

CONCLUSION

After mandibular reconstruction with a vascularized bone transfer, the majority of pediatric patients shows neomandibular growth. Condylar preservation, the inclusion of epiphyseal growth plates or cartilage, and the patients age at the time of reconstruction are essential defining parameters.

Spatial deviations of the temporomandibular joint after oncological mandibular reconstruction

Spatial deviations of the temporomandibular joint (TMJ) after oncological mandibular reconstruction are important to the aesthetic and functional rehabilitation. The aim of this study was to clarify whether and how three dimensionally (3D) printed patient-specific surgical plates, and the preservation of the condyle or ramus, affect spatial deviations of the TMJ. A total of 33 patients who underwent mandibular reconstruction via computer-assisted surgery were included. Regarding absolute deviations, patients in the 3D-printed plate group showed smaller TMJ deviations compared to those in the conventional plate group. There was no difference in absolute deviations of the TMJ regardless of whether the condyle or ramus was preserved. Regarding physiological deviations, the impact on the contralateral TMJ was smaller in the 3D-printed plate group. Patients with both the condyle and ramus removed had significantly higher deviations of the condyle and joint space. In summary, 3D-printed patient-specific surgical plates improved the spatial accuracy of the TMJ. Under physiological conditions, TMJ deviations on the operated side were mainly affected by the preservation of the condyle. Removal of both the condyle and ramus caused more severe spatial interference to the TMJ; this should be further confirmed.

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.

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.

Association between condylar position changes and functional outcomes after condylar reconstruction by free fibular flap

OBJECTIVES

Stable and appropriate condyle positioning is necessary for maintaining temporomandibular joint function. It is unclear if this position remains stable in patients after free fibular flap (FFF) condylar reconstruction. We investigated whether condylar position deviated after reconstruction, and whether this affected functional recovery.

MATERIALS AND METHODS

We retrospectively reviewed 43 patients who underwent conventional FFF condylar reconstruction, and 5 patients who underwent reconstruction by computer-assisted three-dimensional (3D) printing methods. Three-dimensional models were built from cone-beam computed tomography images obtained immediately postoperatively and 1-year postoperatively. The glenoid fossa and fibular condyle centers were used to measure the fibular condyle position in the models. Clinical examination indices, including maximum mouth opening (MMO), pain during chewing/mouth opening, and patient satisfaction with mastication and 1-year outcomes were assessed.

RESULTS

Fibular condyle position changed significantly over 1 year in both groups (P < 0.05). Clinical examination at 1 year after the surgery showed that in the conventional group, the MMO range was ≥ 35 mm in 76.7% of patients and < 35 mm in 23.3% of patients; 4.7% experienced pain during chewing/mouth opening, and 7% were dissatisfied with treatment outcomes. In the 3D printing group, all patients had an MMO range exceeding 35 mm, none had pain, and all were satisfied with functional outcomes.

CONCLUSIONS

The position of the fibular condyle deviates after reconstructive surgery, but it is unlikely to affect functional recovery.

CLINICAL RELEVANCE

These findings can form the basis for evaluation of functional outcomes of patients who have previously undergone condylar reconstruction by FFF.

Evaluation of Effective Condyle Positioning Assisted by 3D Surgical Guide in Mandibular Reconstruction Using Osteocutaneous Free Flap

In the present study, the reproducibility and postoperative stability of a 3D printed surgical guide were evaluated in mandibular reconstruction with an osteocutaneous free flap (OCFF), including a fibular free flap (FFF) and deep circumflex iliac artery free flap (DCIA). Fifteen patients were enrolled, and a 3D surgical guide was fabricated by simulation surgery using preoperative (T0) Computed tomography (CT) images. Mandibular reconstruction was performed with OCFF using the 3D surgical guide. Postoperative CTs were taken immediately, 1 week (T1), and 6 months (T2) after surgery, to evaluate the reproducibility of the 3D surgical guide and condyle stability. Error of the 3D surgical guide ranged from 0.85 to 2.56 mm. There were no differences in reproducibility according to flap type. Condylar error and error at mandible midpoint were significantly different in FFF. However, there was no difference in DCIA error between the condyle and mandible midpoint. Regarding condyle stability 6 months after surgery, condyles moved more than 2 mm (up to 2.85 mm) in FFF, whereas there were no significant movement in DCIA. Careful intraoperative flap fixation and closed postoperative observation should be considered for stable clinical outcome, especially in the case of FFF.

Temporomandibular disorders in head and neck cancers: Overview of specific mechanisms and management

Diagnosis classification system of Temporomandibular disorders (TMD) is based on the biopsychosocial model of pain. The pathogenesis is poorly understood, leading to difficulties in treating these multifactorial conditions. The predisposing factors are pathophysiological, psychological or structural processes that alter the masticatory system and lead to an increase in the risk of development of TMD. The purpose of this integrative review was then to point out the specific mechanisms of TMD in the oral oncologic context to optimize the TMJ functional results in the management of patients with oral oncologic conditions. We explored in this paper the role of Axis II assessment of the biopsychosocial model of pain, the involvement of mechanical concepts such as dental occlusion, mandibular condyle positioning and related-structures reconstruction, and the stomatognathic changes induced by radiation.

Considerations for Mandibular Reconstruction in the Pediatric Patient Following Resection of Malignant Tumors

We recently achieved favorable results in 3 pediatric patients with mandibular osteosarcomas that were treated at our hospital, including with immediate reconstructive surgery performed after tumor resection. Based on a literature review and practical investigation, we discuss the considerations for mandibular reconstruction after malignant lesions are removed from the mandible in children. Mandibular reconstruction for pediatric patients requires an understanding of the changes in bone and soft-tissue architecture due to growth and development at both the donor and recipient sites. Immediate mandibular reconstruction with a free flap can be considered a reasonable option even for young children who require extensive mandibular surgery. However, the variables affecting decisions about treatment planning vary between the different conditions in individual patients, and moreover, these cases are not common in the pediatric population. Therefore, long-term follow-up treatment and further investigations are required for the optimized diagnosis, treatment, and prognosis of pediatric mandibular malignancies.

Vascularized scapula and latissimus dorsi flap for CAD/CAM assisted reconstruction of mandibular defects including the mandibular condyle: technical report and clinical results

Background

Reconstruction of mandibular continuity and function after tumor resection is challenging, particularly in cases including the mandibular condyle. Various approaches for reconstruction after disarticulation resection have been reported. However, the scapula flap has received little attention as a treatment option in these cases.

Patients and methods

Three cases of computer aided design and computer aided manufacturing (CAD/CAM) assisted reconstruction after disarticulation resection using a vascularized scapula and latissimus dorsi flap are reported. All cases required reconstruction of the mandibular ramus and condyle in combination with the reconstruction of large and complex soft tissue defects.

Results

The surgical procedure was deemed successful in all cases. The scapula flap could be placed as preoperatively planned and patients regained their preoperative occlusion pattern and satisfying mouth opening-ranges. The large soft tissue defects could reliably be reconstructed using a latissimus dorsi flap.

Conclusions

The scapula and latissimus dorsi flap can be considered a suitable option for the reconstruction of mandibular disarticulation resection defects in combination with large soft tissue defects.

Changes in Condylar Position After Mandibular Reconstruction With Condylar Head Preservation by Computed Tomography

PURPOSE

Condylar position can change after mandibular reconstruction using the free fibula flap. The present study evaluated changes in condylar position using computed tomography (CT) after mandibular reconstruction with condylar head preservation.

MATERIALS AND METHODS

This retrospective study consisted of 16 patients. CT data of 32 temporomandibular joints (TMJs) were recorded before surgery (T0), 7 to 10 days after surgery (T1), and 16.8 ± 7.4 months after surgery (T2). The anteroposterior condylar position was evaluated using the method of Pullinger and Hollender (Oral Surg Oral Med Oral Pathol 62:719, 1986). Repeated-measures analysis of variance (P = .05) was performed.

RESULTS

Data of 16 patients were obtained for statistical analysis. Condylar position changed over time after mandibular reconstruction. The ipsilateral condyles moved anteroinferiorly after surgery (T0 to T1) and tended to move anterosuperiorly during follow-up (T1 to T2). No major changes were noted in the contralateral condyles.

CONCLUSION

Condylar positions showed obvious changes over time after mandibular reconstruction with condylar preservation. Nevertheless, additional studies are warranted to further evaluate the relation between condylar position and TMJ function.

Free flaps for head and neck cancer in paediatric and neonatal patients

PURPOSE OF REVIEW

To review recent literature on the subject of free tissue transfer options in paediatric head and neck surgery, with a particular emphasis on highlighting the advantages and disadvantages of different reconstructions in the paediatric patient.

RECENT FINDINGS

Free tissue transfer in paediatric patients is predictable and applicable for a wide range of congenital and acquired defects in the head and neck. The free fibula flap is a mainstay of mandibular reconstruction and allows excellent implant-supported prosthodontic rehabilitation and growth potential at the recipient site with little or no donor site morbidity. Other less commonly explored options include the deep circumflex iliac artery flap, scapula flap and medial femoral condyle flap. The gracilis mucle remains the mainstay for facial reanimation with other options including pectoralis minor, rectus abdominis, extensor digitorum brevis and latissimus dorsi. There are compelling arguments for centralization of services and creative strategies in postoperative rehabilitation (e.g. play therapy).

SUMMARY

Free flaps in paediatric patients are a viable option and may even have advantages relative to adults because of the absence of atherosclerosis, purported lower risk of vasospasm and proportionally larger vessel size. Transfer earlier in life maximizes functional potential and 'normalizes' treatment.

Condyle Head Reimplantation Combined With Vascularized Free Flap for Mandibular Reconstruction

Due to the anatomic and functional complexity, reconstruction of the condylar process after mandibular tumor extirpation remains a surgical challenge. The aim of this study was to present the results and experience of condyle head reimplantation combined with vascularized free flap for mandibular reconstruction in our institution. In the current study, the authors evaluated the clinical features of condyle head reimplantation combined with vascularized free flap for mandibular reconstruction in 5 patients with benign mandibular intraosseous lesions from December 2013 to March 2015 in our institution. All patients showed nearly normal mouth opening, with minimal mandibular deviation and joint symptoms. The radiograph data showed that 4 patients had no obvious bone resorption of condyles while only 1 patient had prominent condyle resorption. All the condyles were cut above the condylar neck, with the biggest remaining condyle height being 2.8 cm and the smallest one being 1.1 cm. Moreover, the original vertical height of mandibular ramus was decreased by 2 to 3 mm during the surgery. In conclusion, this study revealed that combining the condyle reimplantation with vascularized free flap constitutes a reliable method in condylar reconstruction and a slight reduction of the vertical height of condyles may help to diminish unfavorable outcomes.

Temporomandibular joint reconstruction

PURPOSE OF REVIEW

Temporomandibular joint (TMJ) reconstruction represents one of the more challenging clinical problems that a head and neck surgeon encounters. Fortunately, the problem is fairly uncommon; however, at the same time, clear clinical guidelines have not been formulated. The goal of this review is to present the established solutions to this difficult reconstructive challenge and highlight key developments that have been recently published.

RECENT FINDINGS

Modern-day approaches to TMJ reconstruction include a handful of surgical modalities: costochondral grafting, revascularized tissue transfer, distraction osteogenesis, and alloplastic temporomandibular joint replacement (APTMJR). Over the past several years, publications have focused primarily on distraction osteogenesis and APTMJR. In particular, APTMJR is emerging as a highly successful and versatile surgical modality when faced with TMJ defects.

SUMMARY

With long-term follow-up after APTMJR approaching 20 years at several of the pioneering centers, alloplastic total joint replacement is emerging as the clinical standard when faced with TMJ defects in a variety of clinical situations. Unfortunately, the dogma of serious complications that occurred during early development may still be stalling widespread acceptance of APTMJR. Due to the complexity of the surgery, its relative infrequency and the lack of exposure in the majority of residency training programs, this surgery is currently best performed by tertiary referral centers.

Stereolithographic model-assisted reconstruction of the mandibular condyle with a vascularized fibular flap following hemimandibulectomy: Evaluation of morphological and functional outcomes

The vascularized fibular flap is one of the standard treatment choices for the reconstruction of the mandible; however, the consequences of condylar restoration have not previously been reported. The use of three-dimensional models allows for a more predictable reconstruction. The purpose of the present study was to assess the outcome of stereolithographic model-assisted reconstruction of the mandibular condyle with a vascularized fibular flap. A total of 5 patients underwent mandibular resection including the condyle and immediate reconstruction with a vascularized fibular flap. A stereolithographic model was used to determine the length and angle of the bony reconstruction. In all patients, the temporomandibular joint (TMJ) disc was preserved, and the contoured fibular end was placed directly into the glenoid fossa under the TMJ disc. To investigate the morphological and functional outcomes, radiographic and clinical examinations were performed, and a food scale questionnaire was administered. The mean period of follow-up was 23 months, and all the flaps were viable. Cosmetic results were generally satisfactory. Radiographic assessment revealed that the end of the fibular graft became round-shaped. None of the patients had abnormal bone resorption, dislocation or ankylosis. The mean value of maximum mouth opening was 31 mm. No patients exhibited difficulties with occlusion. All patients recovered their ability to ingest nearly the same foods that were ingested prior to surgery. The stereolithographic model-assisted reconstruction of mandibular condyle with a vascularized fibular flap is therefore useful for morphological and functional reconstructions of the hemimandible, including condylar defects.

Impact of mandibular condyle preservation on patterns of failure in head and neck cancer

Objective

To determine the role of native condyle preservation in local recurrence after segmental mandibulectomy in patients with head and neck squamous cell carcinoma.

Methods

Retrospective chart review with main outcome measuring local control of cancer.

Results

Between 1994 and 2003, 72 patients (48 men, 24 women) with an average age of 73.5 years without previous treatment underwent segmental mandibulectomy. Fifty-four cases (n = 54) involved the mandible posterior to the mental foramen and are the subject of this review. In 36 patients, the condyle was preserved and mandibular continuity was restored. In 18 patients, condyle and ramus were resected without mandibular reconstruction. Reconstructive modalities included primary closure (3), split-thickness skin graft (3), pedicle flap (19), and free tissue reconstructions (29). Overall local-regional recurrence rate was 22 percent (12 of 54); no recurrences were identified in patients who underwent condylar resection. Recurrences were observed in patients with mandibular reconstruction by both plate and pedicle flap (5 of 9) or (osteo) myocutaneous free flap (7 of 27).

Conclusion

Condylar preservation may predispose patients to local recurrence after segmental mandibulectomy. This does not translate into overall reduction in survival.

The use of computer-aided design/manufacturing (CAD/CAM) technology to aid in the reconstruction of congenitally deficient pediatric mandibles: A case series

BACKGROUND

Microvascular reconstruction of the pediatric mandible, particularly when necessitated by severe, congenital hypoplasia, presents a formidable challenge. Complex cases, however, may be simplified by computer-aided design/computer-aided manufacturing (CAD/CAM) assisted surgical planning. This series represents the senior authors' preliminary experiences with CAD/CAM assisted, microvascular reconstruction of the pediatric mandible.

METHODS

Presented are two patients with hemifacial/bifacial microsomia, both with profound mandibular hypoplasia, who underwent CAD/CAM assisted reconstruction of their mandibles with vascularized fibula flaps. Surgical techniques, CAD/CAM routines employed, complications, and long-term outcomes are reported.

RESULTS

Successful mandibular reconstructions were achieved in both patients with centralization of their native mandibles and augmentation of deficient mandibular subunits. No long-term complications were observed.

CONCLUSIONS

CAD/CAM technology can be utilized in pediatric mandibular reconstruction, and is particularly beneficial in cases of profound, congenital hypoplasia requiring extensive, multi-planar, bony reconstructions.

[Condylar remodelling after temporomandibular joint reconstruction with fibula free flap]

AIM

Mandibular reconstructions with fibula free flap are commonly used in maxillo-facial surgery; termino-lateral mandibulectomy with reconstruction of the ramus and condylar unit is seldom used. Consequences on the temporomandibular joint remain unclear, and the type of reconstruction is still subject to controversy.

METHODS

Six patients were followed after terminal mandibulectomy, reconstructed with fibular free flap. Evaluations of the results were made on functional and radiological criteria.

RESULTS

No patient presented functional disturbances due to reconstruction. Remodeling of the neocondyle extremity was weak in adults but important in children, with modification of morphology and architecture of the condyle in children.

DISCUSSION

Preservation of the disc is recommended. Many techniques are described to improve congruence, preservation and remodeling of the free extremity of the fibula flap. All give similar results. It seems that the real determinant factors on the quality of the result are age, presence of the disc or not, previous surgery performed, with or without radiotherapy.

Condylar disarticulation; analysis of 20 cases from a nigerian tertiary centre

Background:

A disarticulation resection is a variant of mandibular segmental resection in which the condylar articulation is sacrificed. Indication varies from primary condylar lesions to jaw conditions involving the condyle.

Aim:

This retrospective analysis was carried out to highlight the pattern of disarticulation resections carried out in our centre over a five-year period.

Materials and Methods:

Cases of mandibular resection were identified from the operation book. The medical records of patients who had disarticulation resection were then retrieved and analyzed for demography, indications for disarticulations, methods of reconstruction and complications.

Results:

A total of 20 cases of disarticulation with complete records were obtained, this constituted 24.7% of total mandibular resections in the department. There were 9 males and 11 females with a male: female ratio of 1:1.2. The age ranged between 13 and 59 years with a mean of 30.4 years (std. 12.0). Sixteen patients received autogenous bone graft; two were stabilized using Steinman's pins and two with reconstruction plates. One bone graft and one reconstruction plate were removed because of infection and exteriorization respectively. Condyle was not replaced in any case. Outcomes were satisfactory but jaw deviation on opening was a common complaint in all cases.

Conclusion:

Condylar disarticulation accounts for a considerably high percentage of mandibular resection in our centre. Non vascularized immediate bone grafting without actual joint reconstruction was common. No disarticulation was carried out for traumatic reasons.

Advances in temporomandibular joint reconstruction

PURPOSE OF REVIEW

This article reviews the reconstructive techniques commonly employed in temporomandibular joint (TMJ) surgery with an emphasis on recent developments in the field.

RECENT FINDINGS

TMJ reconstruction remains one of the most challenging tasks faced by surgeons who operate in the head and neck, with a variety of autogenous and alloplastic techniques available. The role of alloplastic TMJ reconstruction needs to be reassessed in light of recent literature showing excellent long-term functional outcomes, which reflect advances in prosthetic materials and surgical technique. More recently, transport distraction osteogenesis has been applied to reconstruction of the ramus-condyle unit with promising early results suggesting it may ultimately become the standard of care in selected patients providing a cost-effective approach with low morbidity and excellent functional outcomes.

SUMMARY

The myriad of available TMJ reconstructive options reflect the fact that it remains an evolving field. Although no gold standard currently exists, the various techniques each have their own proponents and potential advantages and drawbacks. Ultimately, the reconstructive surgeon must consider the ablative defect and underlying pathology, the needs of the individual patient, the resources of the providing institution and the capabilities of the surgical team.

Approximation of muscle remnants improves cosmesis following hemimandibulectomy

Hemimandibulectomy should be avoided whenever possible, as it results in significant deterioration in quality of life. If hemimandibulectomy is unavoidable, attempts should be made to reconstruct the bone and soft tissue defect by free tissue transfer or a pedicled flap such as a pectoralis major myocutaneous flap. Bony reconstruction may become challenging when oncological safety mandates removal of the vertical ramus or the condyle. Elderly patients and those with significant co-morbidity are not suitable for prolonged microvascular surgery. Oral cancer is a disease of impoverished nations, where most health institutions may not have the infrastructure to offer microvascular reconstruction. The pectoralis major myocutaneous flap, the workhorse for reconstruction of such defects, occasionally has limitations in terms of bulk, limited arc of rotation, shoulder dysfunction etc. Therefore, hemimandibulectomy and primary mucosal closure continues to be a common procedure in developing nations. A simple technique is proposed with which to improve cosmesis following hemimandibulectomy, utilising the locally available muscle remnants. In highly selected patients, the remaining muscles can be approximated to prevent the lateral hollow that is a common but unacceptable sequel to hemimandibulectomy.

Immediate Mandibular Reconstruction With Microsurgical Fibula Flap Transfer Following Wide Resection for Ameloblastoma

Ameloblastoma, the most common odontogenic tumor, is a slow growing, localized tumor of the facial skeleton. Eighty percent of the tumors affect the mandible. Treatment by wide excision is curative in 95% of cases. Reconstruction by bone grafting has a 20% to 30% nonunion rate. We have treated three large ameloblastomae (>6 cm) with fibula flaps, following resection. All patients have healed. With follow-up times of 2 to 3 years, there has been no evidence of recurrence and no difficulties with postoperative evaluation for recurrent disease. We conclude that the fibula flap is a reliable reconstructive operation following resection of large ameloblastomae.

Free Fibula Flap Mandible Reconstruction in Benign Mandibular Lesions

The mandible may be affected by a variety of pathological conditions such as ameloblastomas, odontogenic keratocysts, central giant cell granulomas, fibro-osseous lesions, and osteomas. They generally are benign, and conservative treatment can be enough in most of the cases. However, they can be clinically aggressive, and especially ameloblastomas, odontogenic keratocysts, and fibro-osseous lesions are prone to recur. The method of treatment remains a matter of controversy in these cases. The aim of this analysis was to study 100 patients who had been treated for benign mandibular lesions, and to emphasize the importance of free fibula flap in the treatment of such lesions.

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.

Recipient Vessel Analysis for Microvascular Reconstruction of the Head and Neck

The selection of recipient vessels that are suitable for microvascular anastomosis in the head and neck region is one of many components that is essential for successful free tissue transfer. The purpose of this study was to evaluate a set of factors that are related to the recipient artery and vein and to determine how these factors influence flap survival. A retrospective review of 102 patients over a 5-year consecutive period was completed. Indications for microvascular reconstruction included tumor ablation (n = 76), trauma (n = 13), and chronic wounds or facial paralysis (n = 13). The most frequently used recipient artery and vein included the facial, superficial temporal, superior thyroid, carotid, and jugular. Various factors that were related to the recipient vessels were analyzed and included patient age, recipient artery and vein, diabetes mellitus, tobacco use, the timing of reconstruction, the method of anastomosis, previous radiation therapy, creation of an arteriovenous loop, and use of an interposition vein graft. Successful free tissue transfer was obtained in 97 of 102 flaps (95%). Flap failure was the result of venous thrombosis in 4 and arterial thrombosis in 1. Statistical analysis demonstrated that anastomotic failure was associated with an arteriovenous loop (2 of 5, P = 0.03) and tobacco use (3 of 5, P = 0.03). Flap failure was not related to patient age, choice of recipient vessel, diabetes mellitus, previous irradiation, the method of arterial or venous anastomosis, use of an interposition vein graft, or the timing of reconstruction.