Restorabite™: Phase II trial of jaw stretching exercises using a novel device for patients with trismus following head and neck cancer.

Patients treated for oral cancer, may experience restricted mouth opening (trismus). Barriers such as cost have limited the utilization of traditional jaw stretching devices, and consequently, patients experience problems with swallowing, oral care, communication, and cancer surveillance. The safety and efficacy of Restorabite™, a new device designed to overcome these barriers, is evaluated prospectively over 12 months. This phase II investigator-led trial included patients with chronic trismus underwent 10-weeks of trismus therapy using Restorabite™. Safety, adherence, changes in mouth opening, and patient-reported outcomes are presented. 114/120 participants with trismus completed the intervention, and 104 had their progress monitored for 12 months. Thirteen participants withdrew due to tumour recurrence. At the completion of the intervention, mouth opening improved by 10.4 mm (p < .001). This increased to 13.7 mm at 12 months (p < .001). Patient reported outcome all significantly improved and 47 participants were no longer classified as having trismus. There were no serious treatment related adverse events. In patients with trismus following head and neck cancer treatment, a 10-week programme of jaw stretching exercises using Restorbite™ safely improves mouth opening and associated quality of life outcomes with high adherence and the benefits are maintained for 12-months.

Medial Femoral Condyle Periosteal Free Flap for Bone Coverage Following Debridement of Intermediate-Stage Osteoradionecrosis of the Jaw.

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.

Ecological characteristics explain neutral genetic variation of three coastal sparrow species.

Eco-phylogeographic approaches to comparative population genetic analyses allow for the inclusion of intrinsic influences as drivers of intraspecific genetic structure. This insight into microevolutionary processes, including changes within a species or lineage, provides better mechanistic understanding of species-specific interactions and enables predictions of evolutionary responses to environmental change. In this study, we used single nucleotide polymorphisms (SNPs) identified from reduced representation sequencing to compare neutral population structure, isolation by distance (IBD), genetic diversity and effective population size (Ne) across three closely related and co-distributed saltmarsh sparrow species differing along a specialization gradient-Nelson's (Ammospiza nelsoni subvirgata), saltmarsh (A. caudacuta) and seaside sparrows (A. maritima maritima). Using an eco-phylogeographic lens within a conservation management context, we tested predictions about species' degree of evolutionary history and ecological specialization to tidal marshes, habitat, current distribution and population status on population genetic metrics. Population structure differed among the species consistent with their current distribution and habitat factors, rather than degree of ecological specialization: seaside sparrows were panmictic, saltmarsh sparrows showed hierarchical structure and Nelson's sparrows were differentiated into multiple, genetically distinct populations. Neutral population genetic theory and demographic/evolutionary history predicted patterns of genetic diversity and Ne rather than degree of ecological specialization. Patterns of population variation and evolutionary distinctiveness (Shapely metric) suggest different conservation measures for long-term persistence and evolutionary potential in each species. Our findings contribute to a broader understanding of the complex factors influencing genetic variation, beyond specialist-generalist status and support the role of an eco-phylogeographic approach in population and conservation genetics.

First Phase Development of a Patient-reported Outcome Measure for Midface Oncology.

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.

Receptors underlying an odorant's valence across concentrations in Drosophila Larvae.

Odorants interact with receptors expressed in specialized olfactory neurons, and neurons of the same class send their axons to distinct glomeruli in the brain. The stereotypic spatial glomerular activity map generates recognition and behavioral response for the odorant. The valence of an odorant changes with concentration, typically becoming aversive at higher concentrations. Interestingly in the Drosophila larvae, the odorant (E)-2-hexenal is aversive at low concentrations and attractive at higher concentrations. We investigate the molecular and neural basis of this phenomenon focusing on how activities of different olfactory neurons conveying opposing effects dictate behaviors. We identify the repellant neuron in the larvae as one expressing the olfactory receptor Or7a, whose activation alone at low concentrations of (E)-2-hexenal elicits an avoidance response in an Or7a dependent manner. We demonstrate that avoidance can be overcome at higher concentrations by activation of additional neurons that are known to be attractive, most notably known activators of Or42a and Or85c. These findings suggest that in the larval stage, the attraction-conveying neurons can overcome the aversion-conveying channels for (E)-2-hexenal.

Co-culture of chondrocytes and stem cells: a review of head and neck cell lines for cartilage regeneration.

INTRODUCTION: Bioprinting, using "bio-inks" consisting of living cells, supporting structures and biological motifs to create customized constructs, is an emerging technique that aims to overcome the challenges of cartilaginous reconstruction of head and neck structures. Several living cell lines and culturing methods have been explored as bio-inks with varying efficacy. Co-culture of primary chondrocytes and stem cells (SCs) is one technique, well established for degenerative joint disease treatment, with potential for use in expanding chondrocyte populations for bio-inks. This study aims to evaluate the techniques for co-culture of primary chondrocytes and SCs for head and neck cartilage regeneration. METHODS: A literature review was performed through OVID/Web of Science/MEDLINE/BIOSIS Previews/Embase. Studies reporting on chondrocytes and SCs in conjunction with co-culture or cartilage regeneration were included. Studies not reporting on findings from chondrocytes/SCs of the head and neck were excluded. Extracted data included cell sources, co-culture ratios and histological, biochemical and clinical outcomes. RESULTS: 15 studies met inclusion criteria. Auricular cartilage was the most common chondrocyte source (n=10), then nasal septum (n=5), articular (n=1) and tracheal cartilage (n=1). Bone marrow was the most common SC source (n=9) then adipose tissue (n=7). Techniques varied, with co-culture ratios ranging from 1:1 to 1:10. All studies reported co-culture to be superior to SC mono-culture by all outcomes. Most studies reported superiority or equivalence of co-culture to chondrocyte mono-culture by all outcomes. When comparing clinical outcomes, co-culture constructs were equivalent to chondrocyte mono-culture in diameter, and equivalent or inferior in wet weight and height. CONCLUSION: Co-culture of primary chondrocytes and SCs is a promising technique for expanding chondrocyte populations, with at least equivalence to chondrocyte mono-culture and superior to SC mono-culture when seeded at the same chondrocyte densities. However, there remains a lack of consensus regarding the optimal cell sources and co-culture ratios.

Novel Sheep Model to Assess Critical-Sized Bone Regeneration with Periosteum for In Vivo Bioreactors.

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.

Amplification, Resistance, and Kinetics of the Jaw Stretching Device (ARK-JSD): analysis of the force variation and implications for trismus therapy.

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.

Pilot Study of Intensive Trismus Intervention Using Restorabite™ During Unilateral Adjuvant Radiation for Head and Neck Cancer.

Trismus commonly arises after surgery for head and neck cancer (HNC) and its severity is potentiated by postoperative radiotherapy. While the benefit of trismus rehabilitation after surgery and radiotherapy is well established, the evidence during radiotherapy is less clear. This may be due to poor adherence to trismus exercises secondary to acute mucositis. This study assessed the feasibility of using a novel trismus device during adjuvant radiotherapy for HNC in patients with acute postoperative trismus. Prospective single-arm cohort feasibility study. Eligible patients had undergone surgery with curative intent for HNC, planned for adjuvant radiotherapy, and were suitable for trismus rehabilitation. Participants completed a 10-week exercise program using a novel jaw stretching device. Study outcomes were adherence, maximal incisal opening (MIO), and trismus-related function and quality of life scores, assessed at baseline, 10 weeks, and 6 months after commencing exercises. Nine patients diagnosed with trismus after primary surgery were recruited. The mean increase in MIO at 10 weeks was 7.8 mm (range -4 to 15 mm, p = 0.03), and at 6 months was 10.6 mm (range 1-26 mm, p = 0.03). Significant improvements were observed in trismus-related quality of life (Gothenburg Trismus Questionnaire; p = 0.04). Adherence to the exercises was 100% in week 1-2, 67% in weeks 3-6, and 100% at 10 weeks (1 month post radiation). This study demonstrates the feasibility of using a novel jaw stretching device during adjuvant radiotherapy. Further evaluation is warranted to assess the effectiveness of early intervention and prevention of trismus during HNC radiotherapy.Level of Evidence: IV.

Associations between patient-level health literacy and diagnostic time intervals for head and neck cancer: A prospective cohort study.

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.

Improving accuracy in nodal staging of oral cancer: Proposal of a new system.

BACKGROUND: Despite introduction of extranodal extension (ENE) into the AJCC 8th edition of oral cancer staging, previous criticisms persist, such as limited discrimination between sub-stages and doubtful prognostic value of contralateral nodal disease. The purpose of this study was to compare our novel nodal staging system, based on the number of positive nodes and ENE, to the AJCC staging system in surgically treated patients. METHODS: Retrospective analysis of 4710 patients with oral squamous cell carcinoma (OSCC) treated with surgery±adjuvant therapy in 8 institutions in Australia, North America and Asia. With overall survival (OS) and disease specific survival (DSS) as endpoint, the prognostic performance of AJCC 8th and 7th editions were compared using hazard consistency, hazard discrimination, likelihood difference and balance. RESULTS: Our new nodal staging system (PN) a progressive and linear increase in hazard ratio (HR) from pN0 to pN3, with good separation of Kaplan Meier curves. Using the predetermined criteria for evaluation of a staging system, our proposed staging model outperformed AJCC 8th and 7th editions in prediction of OS and DSS. CONCLUSION: PN was the lymph node staging system that provided the most accurate prediction of OS and DSS for patients in our cohort of OSCC. Additionally, it can be easily adopted, addresses the shortcomings of the existing systems and should be considered for future editions of the TNM staging system.

Prognostic and predictive biomarkers in head and neck cancer: something old, something new, something borrowed, something blue and a sixpence in your shoe.

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.

When should patients with T1N0 oral squamous cell carcinoma be considered for elective neck dissection?

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.

Ex vivo tissue modelling informs drug selection for rare cancers.

The identification and therapeutic targeting of actionable gene mutations across many cancer types has resulted in improved response rates in a minority of patients. The identification of actionable mutations is usually not sufficient to ensure complete nor durable responses, and in rare cancers, where no therapeutic standard of care exists, precision medicine indications are often based on pan-cancer data. The inclusion of functional data, however, can provide evidence of oncogene dependence and guide treatment selection based on tumour genetic data. We applied an ex vivo cancer explant modelling approach, that can be embedded in routine clinical care and allows for pathological review within 10 days of tissue collection. We now report that ex vivo tissue modelling provided accurate longitudinal response data in a patient with BRAFV600E -mutant papillary thyroid tumour with squamous differentiation. The ex vivo model guided treatment selection for this patient and confirmed treatment resistance when the patient's disease progressed after 8 months of treatment.

Development and validation of a novel TNM staging N-classification of oral cavity squamous cell carcinoma.

BACKGROUND: For oral cavity squamous cell carcinoma (OSCC), extent of extranodal extension (ENE) (minor, ≤2 mm; major, >2 mm) is differentially prognostic, whereas limitations exist with the 8th edition of American Joint Committee on Cancer/International Union Against Cancer TNM N-classification (TNM-8-N). METHODS: Resected OSCC patients at four centers were included and extent of ENE was recorded. Thresholds for optimal overall survival (OS) discrimination of lymph node (LN) features were established. After dividing into training and validation sets, two new N-classifications were created using 1) recursive partitioning analysis (RPA), and 2) adjusted hazard ratios (aHRs) and were ranked against TNM-8-N and two published proposals. RESULTS: A total of 1460 patients were included (pN0: 696; pN+: 764). Of the pN+ cases, 135 (18%) had bilateral/contralateral LNs; 126 (17%) and 244 (32%) had minor and major ENE, and two (0.3%) had LN(s) >6 cm without ENE (N3a). LN number (1 and >1 vs. 0: aHRs, 1.92 [95% confidence interval (CI), 1.44-2.55] and 3.21 [95% CI, 2.44-4.22]), size (>3 vs. ≤3 cm: aHR, 1.88 [95% CI, 1.44-2.45]), and ENE extent (major vs. minor: aHR, 1.40 [95% CI, 1.05-1.87]) were associated with OS, whereas presence of contralateral LNs was not (aHR, 1.05 [95% CI, 0.81-1.36]). The aHR proposal provided optimal performance with these changes to TNM-8-N: 1) stratification of ENE extent, 2) elimination of N2c and 6-cm threshold, and 3) stratification of N2b by 3 cm threshold. CONCLUSION: A new N-classification improved staging performance compared to TNM-8-N, by stratifying by ENE extent, eliminating the old N2c category and the 6 cm threshold, and by stratifying multiple nodes by size.

Trends in free flap reconstruction of the head and neck: a single surgeon series of 1027 free tissue transfers.

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.

How age affects health-related-quality-of-life outcomes in maxillomandibular reconstructive surgery.

INTRODUCTION: Maxillomandibular reconstruction has various functional, aesthetic, and psychosocial effects that can decrease patients' health-related quality of life (HRQOL). The aim of this study was to compare HRQOL outcomes in older and younger patients undergoing maxillomandibular reconstruction. METHODS: A cross-sectional study of patients undergoing maxillomandibular reconstruction surgery between November 2008 and January 2021 was conducted. Participants completed the FACE-Q Head and Neck Cancer Module, M.D. Anderson Dysphagia Inventory (MDADI), and Speech Handicap Index (SHI). Results from these instruments were used to compare HRQOL outcomes in old (≥70 years) and young (<70 years) patients. RESULTS: Ninety-nine patients who underwent maxillomandibular reconstruction completed the instruments (response rate 50%), of which 33 (33%) were aged ≥70 years. Older age was associated with improved FACE-Q speaking (+11.3, P = 0.045), FACE-Q cancer worry (-9.97, P = 0.050), and SHI score (-16.6, P = 0.013). After adjusting for the effect of radiotherapy, age was associated with improved FACE-Q speaking (+16.8, P = 0.012), FACE-Q smiling distress (+12.6, P = 0.040), FACE-Q worry (-11.0, P = 0.032), and SHI scores (-18.4, P = 0.004). Older age was associated with an increased likelihood of postoperative complications (odds ratio (OR) = 2.9, P = 0.02) and medical complications (OR = 4.6, P = 0.012). CONCLUSION: In patients undergoing maxillomandibular reconstruction, older age (≥70 years) was associated with better HRQOL outcomes in domains relating to speech and cancer worry. In all other HRQOL outcomes, the two age groups performed similarly.

Surgical and health related quality of life outcomes following treatment with zygomatic implant perforated (ZIP) flaps.

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.

Minimum detectable change in occlusal load - normative data for healthy and head and neck cancer populations.

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.