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BACKGROUND: We aimed to identify predictors of distant metastatic recurrence (DMR) in patients with head and neck cutaneous squamous cell carcinoma (HNcSCC) with nodal metastases treated with curative intent. METHODS: Predictors of DMR were identified using Cox regression in a multicenter study of 1151 patients. RESULTS: The 5-year risk of DMR was 9.6%. On multivariate analysis, immunosuppression (HR 2.93; 95% CI: 1.70-5.05; p < 0.001), nodal size >6 cm [versus ≤3 cm (HR 2.77; 95% CI: 1.09-7.03; p = 0.032)], ≥5 nodal metastases [versus 1-2 (HR 2.79; 95% CI: 1.63-4.78; p < 0.001)], and bilateral disease (HR 3.11; 95% CI: 1.40-6.90; p = 0.005) predicted DMR. A DMR risk score was developed that stratified risk from 6.6% (no risk factors) to 100% (≥3 risk factors) (p < 0.001). CONCLUSIONS: The risk of DMR in nodal metastatic HNcSCC increases with immunosuppression, nodal size >6 cm, ≥5 nodal metastases, and bilateral disease. A simple DMR risk score estimated prior to treatment may be clinically useful.
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PURPOSE: Rural people with head and neck cancers (HNC) are likely to experience poorer health outcomes due to limited access to health services, so many benefit from models of care that account for rurality. The aim of this review was to synthesise literature on models of care in this population. METHODS: Studies were identified using seven databases: PubMed, PsycINFO, Scopus, Embase, CINAHL, Medline, and Web of Science. Studies that tested or reported a model of care in rural HNC survivors were included. Data on characteristics and outcomes of the models were synthesised according to the domains in the Cancer Survivorship Care Quality Framework, and study quality was appraised. RESULTS: Seventeen articles were included. Eight were randomised controlled trials (seven with a control group and one single-arm study). Three models were delivered online, nine via telehealth, and five in-person. Majority were led by nurses and allied health specialists and most addressed management of physical (n = 9) and psychosocial effects (n = 6), while only a few assessed implementation outcomes such as cost-effectiveness. None evaluated the management of chronic health conditions. CONCLUSION: Positive outcomes were reported for domains of survivorship care that were measured; however, further evaluation of models of care for rural people with HNC is needed to assess effectiveness across all domains of care. IMPLICATIONS FOR CANCER SURVIVORS: Rural cancer survivors are a diverse population with unique needs. Alternative models of care such as shared care, or models personalised to the individual, could be considered to reduce disparities in access to care and outcomes.
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BACKGROUND: Trismus therapy is often delayed after jaw reconstruction to avoid hardware failure or non-union. The aim of this study is to document the forces that have been applied to patients undergoing free flap reconstruction of the oral cavity in the 12 months following oral cavity reconstruction, and to analyze the associations between force and maximal interincisal opening (MIO) over time. METHODS: Participants with trismus after free flap reconstruction of the oral cavity completed a 10-week jaw stretching program using Restorabite™. Primary outcome measures included the minimum and maximal force applied by a trismus device during rehabilitation, MIO, bone union, and health-related quality of life outcomes up to 12 months postoperatively. RESULTS: A mean of 20.6 Newtons (N) was used during passive exercises and 38.9 N during active exercises was used during trismus therapy. The mean increase in MIO for the 45 participants after 10 weeks, 6 months, and 12 months of therapy was 8.4 mm (p < 0.001), 12.6 mm (p < 0.001), 12.7 mm (p < 0.001), respectively. There was no significant difference in the mean minimal (p = 0.37) or mean maximal (p = 0.08) force applied between those who underwent osseous free flap reconstruction compared to fasciocutaneous only, respectively. In patients who underwent osseous reconstruction, 25 (67.6%) had complete bone union and 12 (32.4%) had partial union at 12 months postsurgery. CONCLUSIONS: In participants undergoing osseous free flap reconstruction, there was no association between the force applied to the rates of bone union. Further research to define safe and optimal loading may benefit patients undergoing jaw reconstruction.
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The long-standing divide in Australia between medicine and dentistry has left many with inequitable access to dental care. People with oral cancer, in particular, may have few options for dental rehabilitation after cancer treatment, even with private health insurance. However, 2024 could finally see health care reforms that address these inequities, with significant momentum building in Australia. In this Perspective, we argue for a national approach to reforms that incorporate aspects of preventive health, primary health care, Medicare Benefits Schedule item review, and the value of Private Health Insurance rebates for dental care.
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BACKGROUND: The radiation dose to dysphagia and aspiration-related structures (DARS) for patients undergoing transoral robotic surgery (TORS) and post-operative radiation therapy (PORT) for primary oropharyngeal carcinoma is unknown. METHODS: This prospective study measured swallowing using the MD Anderson Dysphagia Inventory at baseline and then 12-months after PORT. Dosimetric parameters were collected. RESULTS: 19 patients were recruited between 2017 and 2019. Worse swallow function at 12-months after PORT was associated with dose-parameters to the oesophageal inlet muscle, superior pharyngeal constrictor muscle and cervical oesophagus. Mean dose, V50Gy, and V60Gy to the base of tongue and pharyngeal constrictors was significantly lower in those receiving PORT to the neck alone. CONCLUSION: Dose to DARS was lower in patients who received PORT to the neck alone. In patients treated with TORS and PORT, poorer swallowing outcomes at 12 months post-treatment were associated with increased dose to oesophageal inlet muscle, superior constrictor muscle, and cervical oesophagus.
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The present work describes a preclinical trial (in silico, in vivo and in vitro) protocol to assess the biomechanical performance and osteogenic capability of 3D-printed polymeric scaffolds implants used to repair partial defects in a sheep mandible. The protocol spans multiple steps of the medical device development pipeline, including initial concept design of the scaffold implant, digital twin in silico finite element modeling, manufacturing of the device prototype, in vivo device implantation, and in vitro laboratory mechanical testing. First, a patient-specific one-body scaffold implant used for reconstructing a critical-sized defect along the lower border of the sheep mandible ramus was designed using on computed-tomographic (CT) imagery and computer-aided design software. Next, the biomechanical performance of the implant was predicted numerically by simulating physiological load conditions in a digital twin in silico finite element model of the sheep mandible. This allowed for possible redesigning of the implant prior to commencing in vivo experimentation. Then, two types of polymeric biomaterials were used to manufacture the mandibular scaffold implants: poly ether ether ketone (PEEK) and poly ether ketone (PEK) printed with fused deposition modeling (FDM) and selective laser sintering (SLS), respectively. Then, after being implanted for 13 weeks in vivo, the implant and surrounding bone tissue was harvested and microCT scanned to visualize and quantify neo-tissue formation in the porous space of the scaffold. Finally, the implant and local bone tissue was assessed by in vitro laboratory mechanical testing to quantify the osteointegration. The protocol consists of six component procedures: (i) scaffold design and finite element analysis to predict its biomechanical response, (ii) scaffold fabrication with FDM and SLS 3D printing, (iii) surface treatment of the scaffold with plasma immersion ion implantation (PIII) techniques, (iv) ovine mandibular implantation, (v) postoperative sheep recovery, euthanasia, and harvesting of the scaffold and surrounding host bone, microCT scanning, and (vi) in vitro laboratory mechanical tests of the harvested scaffolds. The results of microCT imagery and 3-point mechanical bend testing demonstrate that PIII-SLS-PEK is a promising biomaterial for the manufacturing of scaffold implants to enhance the bone-scaffold contact and bone ingrowth in porous scaffold implants. MicroCT images of the harvested implant and surrounding bone tissue showed encouraging new bone growth at the scaffold-bone interface and inside the porous network of the lattice structure of the SLS-PEK scaffolds.
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Materiales Biocompatibles , Mandíbula , Andamios del Tejido , Animales , Ovinos , Mandíbula/cirugía , Mandíbula/diagnóstico por imagen , Andamios del Tejido/química , Impresión Tridimensional , Análisis de Elementos Finitos , OsteogénesisRESUMEN
STUDY DESIGN: Case report. Osteoradionecrosis (ORN) of the jaw is a potentially devastating consequence of head and neck irradiation. The progression of ORN can lead to loss of bone, teeth, soft tissue necrosis, pathologic fracture, and oro-cutaneous fistula. Reconstructive surgery has mostly been reserved for late-stage disease where segmental resections are frequently necessary. Evidence is emerging to support earlier treatment in the form of debridement in combination with soft tissue free flaps for intermediate-stage ORN. The authors present a case of a 76-year-old male with persistent Notani 2 ORN of the mandible, treated with surgical removal of all remaining mandibular teeth, transoral debridement of all necrotic mandibular bone, and bone coverage with a left medial femoral condyle (MFC) periosteal free flap based on the descending genicular artery. Treatment was uneventful both intraoperatively and postoperatively. Since surgery (15 mo) the patient has remained free from clinical and radiologic signs of ORN. The MFP periosteal free flap provided an excellent result with minimal surgical complexity and morbidity in this case. Such treatment at an intermediate stage likely results in a reduction in segmental resections, less donor site morbidity, less operative time, less overall treatment time, and possibly fewer postoperative complications compared with the status quo.
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Desbridamiento , Colgajos Tisulares Libres , Osteorradionecrosis , Humanos , Masculino , Osteorradionecrosis/cirugía , Anciano , Fémur/cirugía , Enfermedades Mandibulares/cirugía , Periostio/cirugía , Procedimientos de Cirugía Plástica/métodos , Extracción DentalRESUMEN
Background: Facial cancer surgery involving the midface (comprising the lower eyelids, nose, cheeks, and upper lip) can have debilitating life-changing functional, social, and psychological impacts on the patient. Midface symptoms are inadequately captured by existing patient-reported outcome measures (PROMs). PROMs are increasingly used for individual patient care, quality improvement, and standardized reporting of treatment outcomes. This study aimed to present our findings from the first phase of the development of a midface, specifically periocular and nasal, PROM. Methods: After international guidance for PROM development, the first phase comprised identification of salient issues and item generation. Fifteen patients who had midface surgery and 10 clinicians from various specialties with more than 5 years' experience treating these patients were recruited. Semi-structured interviews explored aesthetic, functional, social, and psychological outcomes, with specific attention to deficiencies in current PROMs. Thematic analysis was used to develop an item pool, and group interviews with clinicians were carried out to create and refine PROM scales. Results: Qualitative data from patient interviews were grouped into aesthetic, functional, and psychosocial domains for the eyelids and nose. Ninety-nine draft items were generated across these domains. Following focus group discussions, the final version of the midface-specific PROM contained 31 items (13 eye-specific, 10-nose-specific, eight general midface items). Conclusions: This midface-specific PROM is valuable in assessing and comparing patient-reported outcomes in those who have undergone complex resection and reconstruction of the midface. This PROM is currently undergoing field testing.
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Considerable research is being undertaken to develop novel biomaterials-based approaches for surgical reconstruction of bone defects. This extends to three-dimensional (3D) printed materials that provide stable, structural, and functional support in vivo. However, few preclinical models can simulate in vivo human biological conditions for clinically relevant testing. In this study we describe a novel ovine model that allows evaluation of in vivo osteogenesis via contact with bone and/or periosteum interfaced with printed polymer bioreactors loaded with biomaterial bone substitutes. The infraspinous scapular region of 14 Dorset cross sheep was exposed. Vascularized periosteum was elevated either attached to the infraspinatus muscle or separately. In both cases, the periosteum was supplied by the periosteal branch of the circumflex scapular vessels. In eight sheep, a 3D printed 4-chambered polyetheretherketone bioreactor was wrapped circumferentially in vascularized periosteum. In 6 sheep, 12 double-sided 3D printed 2-chambered polyetherketone bioreactors were secured to the underlying bone allowing direct contact with the bone on one side and periosteum on the other. Our model enabled simultaneous testing of up to 24 (12 double-sided) 10 × 10 × 5 mm bioreactors per scapula in the flat contact approach or a single 40 × 10 mm four-chambered bioreactor per scapula using the periosteal wrap. De novo bone growth was evaluated using histological and radiological analysis. Of importance, the experimental model was well tolerated by the animals and provides a versatile approach for comparing the osteogenic potential of cambium on the bone surface and elevated with periosteum. Furthermore, the periosteal flaps were sufficiently large for encasing bioreactors containing biomaterial bone substitutes for applications such as segmental mandibular reconstruction.
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Sustitutos de Huesos , Periostio , Ovinos , Animales , Humanos , Periostio/patología , Periostio/fisiología , Periostio/cirugía , Regeneración Ósea/fisiología , Osteogénesis/fisiología , Materiales Biocompatibles , Reactores BiológicosRESUMEN
PURPOSE: Jaw-stretching devices, including the Amplification, Resistance, and Kinetics of the Jaw (ARK-JSD), are an effective option for treating trismus after head and neck cancer (HNC) treatment. The force, however, that is applied to the patient's jaw is unknown. METHODS: Ten ARK-JSD devices were constructed for each of the levels of resistance (total of 30 samples). Each sample was tested using a Universal Testing Machine (UTM). RESULTS: The easy, medium, and hard ARK-JSD had a mean maximum force of 12.3, 21.0, and 32.7 Newtons (N) at a mean interincisal distance (IID) of 8.0 mm, 13.0 mm, and 16.0 mm, respectively. The force varied by 6.9 N for the easy and 24.1 N for the hard ARK-JSD. Fatigue analysis demonstrated up to 5.5 N loss of force over 10 weeks. CONCLUSION: The ARK-JSD is a low-cost trismus device that can force between 12.3 and 32.7 N. The variation in resistance may impact efficacy. Understanding this variation will assist clinicians and patients using the ARK-JSD for trismus therapy.
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Trismo , Trismo/terapia , Humanos , Neoplasias de Cabeza y Cuello , Diseño de Equipo , CinéticaRESUMEN
AIMS: To identify adverse pathological features (APF) predicting nodal failure in clinically node negative T1 oral squamous cell carcinoma (OSCC). METHODOLOGY: This study evaluated patients with T1N0 (≤5 mm depth of invasion (DOI) and ≤2 cm diameter) oral cancers from a prospectively maintained database between 1988 and 2020. All patients underwent surgical excision of the primary lesion without neck dissection. Patients underwent three monthly clinical surveillance and salvage neck dissection was performed if nodal relapse was diagnosed. RESULTS: Overall, 141 patients were included. Nodal relapse was reported in 16/141 (11.3%) patients. Factors impacting regional recurrence-free survival were DOI ≥3 mm (HR: 2.4, P < 0.001), maximum tumour diameter ≥12 mm (HR: 1.1, P = 0.009), perineural invasion (PNI) (HR 7.5, P = 0.002) and poor differentiation (HR 5.3, P = 0.01). Rates of nodal relapse increased from 2% amongst patients with no APFs to 100% for those with four APFs. Patients with two or more APFs had significantly poorer 5-year regional recurrence-free survival (94.8% vs. 56.3%, P < 0.001). CONCLUSION: Patients with T1N0 OSCC with two or more APFs (DOI ≥3 mm, diameter ≥12 mm, PNI or poor differentiations) should be considered for elective neck dissection.
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Procedimientos Quirúrgicos Electivos , Neoplasias de la Boca , Disección del Cuello , Estadificación de Neoplasias , Humanos , Disección del Cuello/métodos , Masculino , Femenino , Neoplasias de la Boca/cirugía , Neoplasias de la Boca/patología , Neoplasias de la Boca/mortalidad , Persona de Mediana Edad , Procedimientos Quirúrgicos Electivos/métodos , Anciano , Carcinoma de Células Escamosas/cirugía , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/mortalidad , Adulto , Recurrencia Local de Neoplasia/epidemiología , Estudios Retrospectivos , Metástasis Linfática , Anciano de 80 o más Años , Invasividad NeoplásicaRESUMEN
A biomarker is a measurable indicator of biological or pathological processes or the response to an exposure or intervention and is used to guide management decisions. In head and neck pathology, biomarkers are assessed by histological criteria and immunohistochemical and molecular studies. Surgical resection remains the mainstay of management of many head and neck malignancies. Adjuvant radiotherapy and/or systemic therapy may be administered depending on the presence of adverse prognostic factors identified on histopathological or immunohistochemical examination. In this review, we outline the clinically relevant prognostic and predictive factors in head and neck malignancies including conventionally recognised factors such as tumour size, depth of invasion, lymphovascular and perineural invasion and margin status as well as novel evolving factors such as recurrent genetic rearrangements and assessment of immune checkpoints. Practical issues are discussed to assist with recognising and reporting of these factors. A summary of useful tools such as structured pathology report formats is also included to assist with comprehensive reporting of all clinically relevant parameters, minimise risk and improve workflow efficiencies.
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Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Humanos , Pronóstico , Carcinoma de Células Escamosas/patología , Zapatos , Neoplasias de Cabeza y Cuello/diagnóstico , Biomarcadores , Estudios RetrospectivosRESUMEN
BACKGROUND: Health literacy (HL) comprises skills and knowledge required to understand, access, and make decisions about healthcare. Our aim was to examine associations between patient HL and time intervals (defined in the Aarhus statement) along the pathway to treatment of head and neck cancer (HNC). METHODS: A prospective cohort study was conducted from October 2018 to March 2020. Participants completed the Health Literacy Questionnaire (HLQ®) and described key events and dates along the pathway to treatment using validated questionnaires. Correlations between six diagnostic time intervals and domains of HL were explored, and factors predicting exceeding maximum acceptable timeframes were assessed using logistic regression. RESULTS: One hundred patients with a diagnosis of HNC within the preceding 6 months were recruited. HLQ® Domain 2 (sufficient information to manage health) was significantly negatively associated with four intervals: the patient interval (first symptom to first presentation), primary care interval (first presentation to referral to secondary care), diagnostic interval (first presentation to diagnosis), and total interval (first symptom to treatment onset); correlation coefficients -0.25 to -0.27 (P < 0.05). Domain 8 (ability to find good information) was significantly negatively associated with three intervals (primary care interval, diagnostic interval, and total interval; correlation coefficients -0.23 to -0.34; P < 0.05). Higher education, age, and comorbidity levels were associated with shorter patient and diagnostic intervals. CONCLUSIONS: HL may be a potential target to improve timeliness of HNC diagnosis and reduce disparities in outcomes.
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Neoplasias de Cabeza y Cuello , Alfabetización en Salud , Humanos , Estudios Prospectivos , Neoplasias de Cabeza y Cuello/diagnóstico , Neoplasias de Cabeza y Cuello/terapia , Pacientes , Comorbilidad , Encuestas y CuestionariosRESUMEN
BACKGROUND: The zygomatic implant perforated (ZIP) flap is a novel approach to the challenge of reconstructing the maxilla. We report on our experience using the ZIP flap technique for patients undergoing infrastructure maxillectomy at Chris O'Brien Lifehouse, Sydney, Australia. METHODS: Thirteen patients who underwent a ZIP flap reconstruction between August 2019 and August 2021 were identified. Demographic, surgical, and histopathological information was collected. Health Related Quality of Life (HRQOL) was assessed using the FACE-Q Head and Neck Cancer module, the M.D. Anderson Dysphagia Inventory, and the Speech Handicap Index. RESULTS: A total of 44 zygomatic implants were placed, of which 42 (95%) survived. The median time from surgery to dental rehabilitation was 35 days. HRQOL data was available for nine patients over 24 months, demonstrating improved speech and swallowing outcomes over the follow up period. CONCLUSIONS: The ZIP flap is a reproducible surgical technique that facilitates rapid dental rehabilitation post infrastructure maxillectomy.
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Procedimientos de Cirugía Plástica , Calidad de Vida , Colgajos Quirúrgicos , Cigoma , Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Cigoma/cirugía , Procedimientos de Cirugía Plástica/métodos , Maxilar/cirugía , Resultado del Tratamiento , Adulto , Estudios Retrospectivos , Implantes Dentales , Neoplasias Maxilares/cirugíaRESUMEN
BACKGROUND: Free tissue transfer has fundamentally changed head and neck surgery, enabling reliable reconstruction of large defects with better function and aesthetics. This study assesses two decades of trends in free flap reconstruction, and how disease incidence, survival, surgeon caseload, team approach, and technology have impacted practice. METHODS: Retrospective analysis of 1027 head and neck free flaps from 2006 to 2022. Outcomes examined include chronological changes in flap selection, indication, length of stay, incorporation of virtual surgical planning (VSP), annual caseload, survival, and their associations with the single versus multi-team approach. RESULTS: There were 764 soft-tissue and 263 osseous reconstructions utilizing 21 different flaps. Anterolateral thigh and radial forearm accounted for 76.7% of soft tissue flaps, with recent increase in superficial circumflex iliac perforator flaps in young patients. Osseous flap proportion remained stable, but fibula flaps increased five-fold with more VSP, dental implants, oral cancer, and multi-team surgery. Outcomes such as complication rates, length of stay and disease specific/overall survival have improved over time despite increasing complexity (P = 0.001, P = 0.001, P < 0.001, and P < 0.001, respectively). However, there was no significant difference in operative time, complication rate, or disease specific/overall survival between single team or multi-team approaches (P = 0.45, P = 0.054, P = 0.57, and P = 0.60, respectively). CONCLUSION: Single and multi-team approaches may have similar fundamental outcomes, but as caseload, complexity, and life-expectancy increases, both patients and surgeons benefit from a collaborative multi-team approach that focuses on improving long-term functional outcomes.
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Colgajos Tisulares Libres , Neoplasias de Cabeza y Cuello , Procedimientos de Cirugía Plástica , Cirujanos , Humanos , Neoplasias de Cabeza y Cuello/cirugía , Estudios RetrospectivosRESUMEN
Traditionally, pain has been a signal to de-intensify jaw exercises for trismus to prevent tissue damage. It is unknown whether patients who have undergone surgery or radiotherapy for head and neck cancer have sufficient sensation to detect changes in occlusal load. This study sought to compare the minimum detectable occlusal load in a cohort of patients with head and neck cancer (HNC) and compare this with healthy controls. Twenty patients who were treated for HNC and 20 healthy controls were recruited from a single institution. A purpose-built pressure transducer was used to measure the minimum detectable force (measured in Newtons) applied to the jaw and the interincisal distance. Analysis was conducted using a mixed effects linear regression. The mean minimum detectable occlusal load in patients with HNC was 18.7N compared to 4.5N in healthy controls (mean difference 14.3N, 95% CI 12.2N to 16.4N, p < 0.001). Adjusted IID predicted force (0.15N per-mm IID, 95% CI 0.09 to 0.2, p < 0.001) with a weak interaction between treatment with radiotherapy and IID in HNC patients (p = 0.85). Patients who have been treated for HNC are less sensitive to changes in force applied to the jaw. This is concerning given that most jaw stretching devices use an unregulated and unknown amount of force to achieve greater mouth opening.
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Neoplasias de Cabeza y Cuello , Humanos , Neoplasias de Cabeza y Cuello/radioterapia , Trismo/etiología , Terapia por Ejercicio , Estado de Salud , Ejercicio Físico , Calidad de VidaRESUMEN
Autologous bone replacement remains the preferred treatment for segmental defects of the mandible; however, it cannot replicate complex facial geometry and causes donor site morbidity. Bone tissue engineering has the potential to overcome these limitations. Various commercially available calcium phosphate-based bone substitutes (Novabone®, BioOss®, and Zengro®) are commonly used in dentistry for small bone defects around teeth and implants. However, their role in ectopic bone formation, which can later be applied as vascularized graft in a bone defect, is yet to be explored. Here, we compare the above-mentioned bone substitutes with autologous bone with the aim of selecting one for future studies of segmental mandibular repair. Six female sheep, aged 7-8 years, were implanted with 40 mm long four-chambered polyether ether ketone (PEEK) bioreactors prepared using additive manufacturing followed by plasma immersion ion implantation (PIII) to improve hydrophilicity and bioactivity. Each bioreactor was wrapped with vascularized scapular periosteum and the chambers were filled with autologous bone graft, Novabone®, BioOss®, and Zengro®, respectively. The bioreactors were implanted within a subscapular muscle pocket for either 8 weeks (two sheep), 10 weeks (two sheep), or 12 weeks (two sheep), after which they were removed and assessed by microCT and routine histology. Moderate bone formation was observed in autologous bone grafts, while low bone formation was observed in the BioOss® and Zengro® chambers. No bone formation was observed in the Novabone® chambers. Although the BioOss® and Zengro® chambers contained relatively small amounts of bone, endochondral ossification and retained hydroxyapatite suggest their potential in new bone formation in an ectopic site if a consistent supply of progenitor cells and/or growth factors can be ensured over a longer duration.