Clinical factors associated with postoperative complications and the functional outcome in mandibular reconstruction

Updates on temporomandibular joint reconstruction following ablative surgery

PURPOSE OF REVIEW

Considerations regarding reconstruction of the temporomandibular junction (TMJ) following ablation have been underreported in head and neck surgery literature. Here, we discuss the complexity of reconstructing this unique joint and highlight the benefits and drawbacks of free tissue transfer. Additionally, we address the growing role of customized alloplastic implants and virtual surgical planning technologies in TMJ reconstruction.

RECENT FINDINGS

Technological advances in computerized manufacturing, 3D printing, and virtual reality have led to a recent burgeoning in patient-specific customization that may become the method of choice in these complex reconstruction cases.

SUMMARY

Since trauma and malignancy rarely compromise the entire TMJ, guidelines currently do not exist regarding how to best reconstruct the region in these unique cases. The methods that work in ankylosis and other intrinsic joint diseases are likely less appropriate in this patient population. Recent literature has reported improved patient outcomes and reduced operative times with virtual surgical planning techniques that may optimize autogenous graft approaches.

Evaluation of aesthetic outcomes of mandibular reconstruction using artificial intelligence

BACKGROUND

Although vascularized bone graft (VBG) transfer is the current standard for mandibular reconstruction, reconstruction with a mandibular reconstruction plate (MRP) and with a soft-tissue flap (STF) alone remain crucial options for patients with poor general conditions. However, objective aesthetic outcome evaluations for these methods are limited.

METHODS

In a retrospective analysis of 65 patients (VBG, 33; MRP, 19; and STF, 13), mandibular asymmetry value was calculated for each patient's photograph using facial recognition AI, with a higher value indicating worse asymmetry.

RESULTS

The MRP group had a value comparable to the VBG group regardless of mandibular defect types. The STF group had a significantly higher value than the VBG group.

CONCLUSIONS

Regarding cosmesis, STF was inferior to VBG, whereas MRP was comparable to VBG, even for anterior defects for which rigid reconstruction is mandatory. However, MRP's risks of plate-related complications limit its use to cases where VBG is contraindicated or with poor prognosis.

LEVEL OF EVIDENCE: 4

A novel alloplastic grid reconstruction plate for the mandible - Retrospective comparative clinical analysis of failure rates and specific complications

PURPOSE

This study aimed to investigate the effect of three different osteosynthesis plate systems on failure rates and complications after continuity-interrupting mandibular resections with alloplastic reconstructions.

MATERIALS AND METHODS

Records of respective patients from 2010 to 2020 were analyzed retrospectively. The analyses included the osteosynthesis plate type (2.4 MANDIBULAR (RP1: MANDIBULAR [Medicon®, Tuttlingen, Germany]; RP2: Modus® Reco 2.5 [Medartis®, Basel, Switzerland]; and RP3: Modus 2 Mandible [Medartis®, Basel, Switzerland]), extent & location of the defect, age, sex, radiotherapy, and nicotine abuse. In case of failure, timepoint, and the problem, namely oral/extraoral dehiscence, screw loosening, and plate fractures that led to removal, were analyzed. Complications were classified according to Clavien-Dindo system.

RESULTS

A total of 136 patients were included. The mean follow-up time was 18 ± 26 months. Survival rates after 1, 2, and 5 years were 69.9%, 66.9%, and 64.7%, respectively. Although survival was not significantly associated with the reconstruction system, the most frequent complications were seen in cases of RP1 & RP2 when compared to RP3 (p = 0.033). In brief, dehiscences were seen significantly less often in cases of RP3 (12.5%) when compared to RP1 (44.7%) and RP2 (26.9%; p = 0.024). Fractures of the osteosynthesis systems occurred in 3 of 4 cases (75%) with RP1, in 1 of 4 cases (25%) using RP2, and in no single case using the RP3 system (p = 0.03). Most of the observed complications occurred up to 12 months postoperatively. A total plate survival rate of 64.7% and a total plate complication rate of 47.8% were seen.

CONCLUSION

In conclusion, it seems that RP3 should be preferred over RP1 and RP2 regarding failure rates and complications.

Inclusion of calcium phosphate does not further improve in vitro and in vivo osteogenesis in a novel, highly biocompatible, mechanically stable and 3D printable polymer

At a time of unpredictable challenges for health, one trend is certain: there is an exceedingly high demand for functional implants, particularly bone grafts. This has encouraged the emergence of bone tissue engineering substitutes as an alternative method to conventional bone grafts. However, the current approaches in the field face several limitations that have prevented the ultimate translation into clinical settings. As a result, many attempts have been made to fabricate synthetic bone implants that can offer suitable biological and mechanical properties.Light curable methacrylate-based polymers have ideal properties for bone repair. These materials are also suitable for 3D printing which can be applicable for restoration of both function and aesthetics. The main objective of this research was to investigate the role of calcium phosphate (CaP) incorporation in a mechanically stable, biologically functional and 3D printable polymer for the reconstruction of complex craniofacial defects. The experimental work initially involved the synthesis of (((((((((((3R,3aR,6S,6aR)- hexahydrofuro[3,2-b]furan-3,6-diyl)bis(oxy))bis(ethane-2,1- 48 diyl))bis(oxy))bis(carbonyl))bis(azanediyl))bis(3,3,5-trimethylcyclohexane-5,1- 49 diyl))bis(azanediyl))bis(carbonyl))bis(oxy))bis(ethane-2,1-diyl) bis(2-methylacrylate) referred to as CSMA and fabrication of composite discs via a Digital Light Printing (DLP) method. The flow behaviour of the polymer as a function of CaP addition, surface remineralisation potential, in vitro cell culture, using MC3T3 and Adipose-Derived Mesenchymal Stem Cells (ADSCs) and ex ovo angiogenic response was assessed. Finally, in vivo studies were carried out to investigate neo-bone formation at 4- and 8-weeks post-implantation. Quantitative micro-CT and histological evaluation did not show a higher rate of bone formation in CaP filled CSMA composites compared to CSMA itself. Therefore, such polymeric systems hold promising features by allowing more flexibility in designing a 3D printed scaffold targeted at the reconstruction of maxillofacial defects.

Effect of Radiotherapy on Functional and Health-Related Quality of Life Outcomes after Jaw Reconstruction

Simple Summary

Reconstructive surgery is critical to restore form and function after treatment for head and neck cancer (HNC). The aim of this cross-sectional study was to describe long-term quality of life (QoL) and functional outcomes among patients with a history of HNC who underwent reconstruction of the mandible and/or maxilla. Patients who had radiotherapy either before or after their index reconstruction reported significantly worse functional and QoL outcomes, including speech, swallowing, eating and drinking, appearance, smiling, and satisfaction with information. Swallowing, salivation, oral competence, and satisfaction with information worsened with increasing time since surgery. Women and younger patients also reported worse functional and QoL outcomes, especially speech and facial aesthetics. Understanding long-term outcomes of jaw reconstruction is important for both patients and clinicians to make evidence-based decisions about treatment options. We have identified several groups at risk of poorer outcomes that may benefit from enhanced pre-operative counselling and post-operative monitoring.

Abstract

Long-term health-related quality of life (HRQOL) and functional outcomes following mandibular and maxillary reconstruction are lacking. To determine these outcomes, a cross-sectional study of patients with a history of cancer who underwent jaw reconstruction was undertaken. Participants were identified from a database of jaw reconstruction procedures at the Chris O’Brien Lifehouse (Sydney, Australia). Eligible patients had at least one month follow-up, were aged ≥18 years at surgery, and had history of malignancy. HRQOL was measured using the FACE-Q Head and Neck Cancer Module (FACE-Q H&N). Functional outcomes were measured using the FACE-Q H&N, MD Anderson Dysphagia Inventory (MDADI) and Speech Handicap Index (SHI). Ninety-seven questionnaires were completed (62% response rate). Mean age of respondents was 63.7 years, 61% were male, and 64% underwent radiotherapy. Treatment with radiotherapy was associated with worse outcomes across 10/14 FACE-Q H&N scales, three MDADI subscales and one composite score, and the SHI. Mean differences in scores between irradiated and non-irradiated patients exceeded clinically meaningful differences for the MDADI and SHI. Issues with oral competence, saliva, speaking, and swallowing worsened with increasing time since surgery. Younger patients reported greater concerns with appearance, smiling, speaking, and cancer worry. Women reported greater concerns regarding appearance and associated distress. History of radiotherapy substantially impacts HRQOL and function after jaw reconstruction. Age at surgery and gender were also predictors of outcomes and associated distress. Pre-treatment counselling of patients requiring jaw reconstruction may lead to improved survivorship for patients with head and neck cancer.

Use of CAD-CAM Bridging Mandibular Prosthesis in Osteonecrosis of the Jaw: The Experience of Our School

Osteonecrosis of the jaw (ONJ) is a disease that affects the jaw. It is mainly related to radiation or bisphosphonates therapy, and the symptoms and signs consist of pain, bone exposure, inflammation of the surrounding soft tissue swelling, and secondary infection or drainage. In the case of advanced disease of the mandibular area, the treatment of choice is mandibular resection and reconstruction. In the present study, we report a case series of patients affected by ONJ and treated with a customised bridging mandibular prosthesis-only technique. From 2016 to 2018, we treated five consecutive patients affected by ONJ: three patients were affected by biphosphonate-related osteonecrosis of the mandible (BRONJ) and two were affected by osteoradionecrosis of the mandible (ORNJ). Three patients needed a soft tissue free flap to permit optimal wound closure, intra- and/or extraorally. All reconstructive procedures were carried out successfully, with no major or minor microvascular complication. The average postoperative follow-up was 24.8 (range 10–41) months. Considering that microvascular bone transfer is a high-risk procedure in BRONJ patients, we can conclude that the positioning of a customised bridging mandibular prosthesis (CBMP), whether or not associated with a microvascular soft tissue transfer, is a safe technique in terms of surgical outcome and feasibility.

Investigation of Surgical Site Infections and Bacteria Detected Following Neck Dissection in Patients with Oral Cancer

During dissection for oral cancer, there is a high probability of bacteria indigenous to the oral cavity migrating to the surgical field in the neck due to the opening of new pathways of communication with the oral cavity. The risk of postoperative surgical site infection (SSI) in such patients is high due to malnutrition arising from perioperative eating disorders and dysphagia. Neck infections after neck dissection in oral cancer patients were investigated to elucidate the development of SSIs and their relationship with the results of bacterial culture.A total of 86 patients with oral squamous cell carcinoma who underwent neck dissection between January 2012 and December 2016 were enrolled. Ten factors were selected for investigation: (1) sex; (2) age; (3) primary site; (4) type of dissection; (5) whether or not there was a new pathway of communication between the oral cavity and the neck; (6) operative time; (7) blood loss; (8) number of drainage days; (9) amount of drainage at the time of drain removal; and (10) whether or not there was an SSI. Bacteria isolated from the catheter tip on drain removal were also investigated. Significant differences were observed between patients with and without SSIs (p-0.010) according to the presence of a new pathway of communication between the oral cavity and the neck (p-0.004); operative time (p-0.007); number of drainage days (p-0.029); or the amount of drainage at the time of drain removal. The present results indicate that selecting antibiotics appropriate to each patient and administering perioperative oral care are important in preventing SSIs.

Iliac crest bone grafting for mandibular reconstruction: 10-year experience outcomes

Purpose

To evaluate 10-year patient data related to mandibular reconstruction with NVBG at a tertiary academic center.

Patients and Methods

Sixty patients with mandibular mandibular reconstruction were included. Patients were divided to continuity defect and non-continuity defect. Pathology lesion, immediate reconstruction, smoking habit, medical comorbidities, site and size of the defect, surgical approach, intraoperative perforation, cadaveric bone use, and maxilla-mandibular fixation use were analyzed as factors of influence on success. Success was defined as maintenance of more than 50% of graft for non-continuity defects (NCD) and bone continuity and stability for continuity defect (CD), and absence of infection on last follow up upon clinical and radiographic examination. Complications were classified as minor or major.

Results

The reconstruction was successful in 28 (87%) of CD patients and 23 (82.1%) of NCD patients. Analyses showed that the size of defect was significantly associated with failure. All 4 failed cases of CD had defects more than 9 cm. Four patients had major complications and 43 minor complication.

Conclusions

Nonvascularized iliac crest bone grafts are highly successful in mandibular continuity reconstruction for non-Cancer patients and should be considered as first choice for defects less than 9 cm. They are less predictable for defects larger than 9 cm but can be considered in these cases with osteoconductive cribs. Symphysis involvement may or may not be associated with lower success rate if our protocol is followed.

Design of a customised bridging mandibular prosthesis for complex reconstruction: a pilot study

The gold standard for mandibular reconstruction is universally recognised and consists of the replacement of the bony part of the mandible with a bony microvascular free flap supported by a reconstructive plate. Although this procedure is feasible and reproducible in most patients, at times poor oncological prognosis or poor performance status force surgeons to consider other reconstructive solutions. In these cases, the main alternative in reconstructing a mandibular defect is represented by bridging plates combined with soft tissue flaps. However, repairing a mandibular defect with a reconstructive plate only can lead to a series of diverse complications. The most frequent complications reported are rupture and oral exposure of the plate. In this paper, we describe a new method for mandibular reconstruction using a customised bridging mandibular prosthesis (CBMP) without bone free flap.

A "no-touch-technique" in mandibular reconstruction with reconstruction plate and free flap transfer

OBJECTIVE

Mandibular reconstruction with a mandibular reconstruction plate (MRP) and free flap transfer can involve serious plate-related complications. The aim of our study is to present our new "no-touch-technique" which keeps an MRP not contaminated to saliva during the entire operation for the reduction of plate-related complications.

PATIENTS AND METHODS

Data were retrospectively collected on 29 patients who had undergone segmental mandibulectomy for head and neck tumor and mandibular reconstruction with an MRP and free flap transfer from 2004 to 2013; 12 patients were reconstructed with our no-touch-technique from 2010 to 2013 (no-touch-technique group), and 17 patients with the conventional technique from 2004 to 2009 (conventional group). A rectus abdominis musculocutaneous flap or anterolateral thigh flap was transferred in all patients. The rates of perioperative recipient site complications including total flap necrosis, partial flap necrosis, wound infection, fistula formation and wound dehiscence, and reoperation for complications were compared between the groups.

RESULTS

All flaps were successfully transferred although one venous thrombosis formation occurred in the conventional group. The rate of wound infection in the no-touch-technique group (8.3%) was significantly lower than that in the conventional group (47.1%) (P = 0.04). Additionally, the rate of fistula formation in the no-touch-technique group (8.3%) tended to be lower than that in the conventional group (29.4%) (P = 0.35).

CONCLUSION

The results of our study showed that our no-touch-technique may be a safe and effective procedure for the prevention of perioperative plate-related complications for mandibular reconstruction with an MRP and free flap transfer.

Reconstruction of composite oral cavity defects with temporalis flaps after prior treatment

BACKGROUND

Reconstruction of composite oral cavity defects in the setting of prior surgery and radiotherapy presents a significant challenge. Although free tissue transfer has shown success in such situations, it is not without considerable risk. Regional pedicled flaps may provide a more suitable alternative. In certain patients, however, severe soft tissue fibrosis makes more conventional regional flaps impractical or impossible. In these situations, temporalis flaps (temporalis muscle and temporoparietal fascia flaps) are versatile options for coverage of complex defects.

OBJECTIVE

To report our experience using pedicled temporalis flaps for reconstruction of composite oral cavity defects in patients with significant co-morbidities and prior treatment.

METHODS

Three patients were identified and their medical records were reviewed. Their clinical courses and functional outcomes are described. We include a discussion of the operative technique and relevant literature.

RESULTS

All patients had previously undergone extensive treatment. One patient needed reconstruction after resection of a third head and neck malignancy and two patients presented for treatment of osteoradionecrosis. A temporalis muscle flap was used to reconstruct composite oral cavity defects in two patients and a combined temporalis muscle and temporoparietal fascia flap was used for independent defects in one patient. All flaps survived. Functional status and pain improved or stabilized in all patients. There were no major or minor complications.

CONCLUSION

In previously treated fields, where more conventional flaps are impractical, temporalis flaps are a suitable alternative to achieve a stable healing wound and prevent worsening of functional status.

Predictive factors for premature loss of Martin 2.7 mandibular reconstruction plates

Mandibular reconstruction with a plate, with or without a vascularised free (bone) flap, is commonly used to treat patients with a segmental mandibular defect. Common complications are loosening of the osteosynthesis screws, malposition, intraoral or extraoral exposure, or infection. To define prognostic factors for premature loss of such plates and improve future planning, we designed a retrospective study of all patients operated on between 2005 and 2011 for reconstruction of a mandibular segmental defect with a reconstruction plate with or without a free vascularised (bone) flap. Prognostic factors collected from medical records were the patient's age, sex, and American Society of Anesthesiologists (ASA) grade; treatment with radiotherapy; whether they had diabetes or smoked; the site of the mandibular defect; whether there was a dental occlusion; the number of screws used on each side, and the use of a free vascularised (bone) flap; and whether the diagnosis was of oral cancer, benign tumour, or trauma. One hundred patients were included, 79 with oral cancer, 19 with benign tumours, and 2 with trauma. In 20 patients the Martin 2.7 reconstruction plate failed. Diabetes and smoking were significant prognostic factors for premature loss of the reconstruction plate with a hazard ratio of 2.95 (95% CI 1.068-8.172), p value=0.04, for diabetes, and 2.42 (95% CI 1.006-5.824), p value=0.05, for smoking. Smokers and diabetic patients have a higher risk of failure after mandibular reconstruction with a 2.7 reconstruction plate.

Metals for bone implants. Part 1. Powder metallurgy and implant rendering

New metal alloys and metal fabrication strategies are likely to benefit future skeletal implant strategies. These metals and fabrication strategies were looked at from the point of view of standard-of-care implants for the mandible. These implants are used as part of the treatment for segmental resection due to oropharyngeal cancer, injury or correction of deformity due to pathology or congenital defect. The focus of this two-part review is the issues associated with the failure of existing mandibular implants that are due to mismatched material properties. Potential directions for future research are also studied. To mitigate these issues, the use of low-stiffness metallic alloys has been highlighted. To this end, the development, processing and biocompatibility of superelastic NiTi as well as resorbable magnesium-based alloys are discussed. Additionally, engineered porosity is reviewed as it can be an effective way of matching the stiffness of an implant with the surrounding tissue. These porosities and the overall geometry of the implant can be optimized for strain transduction and with a tailored stiffness profile. Rendering patient-specific, site-specific, morphology-specific and function-specific implants can now be achieved using these and other metals with bone-like material properties by additive manufacturing. The biocompatibility of implants prepared from superelastic and resorbable alloys is also reviewed.