Health-related quality of life in maxillectomy patients undergoing dentoalveolar rehabilitation

Retrospective study of the deep circumflex iliac artery flap and the vascularized fibula free flap for maxillary defect repair

OBJECTIVES

The deep circumflex iliac artery flap (DCIA) and vascularized fibular free flap (FFF) are mainstay flaps for maxillary defect reconstruction. This study compared the functional outcomes and success rates of these flaps to provide midface reconstruction strategies.

MATERIALS AND METHODS

Maxillary defects reconstructed with DCIA or FFF at the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology between May 2016 and May 2023 were retrospectively analyzed. The length, width, and height of the grafted bone segments; intermaxillary distance; buttress reconstruction rate (BRR); dental arch reconstruction rate (DAR); success rate; and dental implantation rate were compared.

RESULTS

The DCIA and FFF groups had 33 and 27 patients, respectively. Success rate in the DCIA group was 93.94 % and 100 % in the FFF group. The DCIA length was less than that of FFF; however, the width and height were significantly larger. 87.10 % of cases in the DCIA group were classified as Brown class b and c, 51.85 % of cases in the FFF group were classified as Brown class d. The average BRR in the DCIA group was 69.89 % ± 16.05 %, which was significantly higher than that in the FFF group. A total of 38.7 % and 11.1 % patients in the DCIA and FFF groups, respectively, had completed implantation.

CONCLUSION

DCIA has a greater width and height, and is more suitable for repairing Brown class b and c defects, providing sufficient bone for implantation, while the FFF is longer and more suitable for Brown class d defect reconstruction.

A Preclinical Trial Protocol Using an Ovine Model to Assess Scaffold Implant Biomaterials for Repair of Critical-Sized Mandibular Defects

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.

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.

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.

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.

Clinical application of 3-dimensional tissue volume assessment using CloudCompare

Adjunctive procedures, including autologous fat grafting and surgical debulking, may be required to optimise facial contours following maxillomandibular reconstruction. A standardised method for the quantitative analysis of volumetric change and the impact of restoration of facial symmetry on health-related quality of life remains unclear. We use two case studies to illustrate the value of a combination of objective 3-dimenmsional (3D) measurements, clinical assessments, and patient-reported outcomes, using the FACE-Q questionnaire to elucidate the benefits of adjunctive procedures.

Comprehensive Analyses of Masticatory Function in Maxillectomy Patients with Functioning Removable Prostheses: A Retrospective Cross-Sectional Study

The aim of this retrospective cross-sectional study was to comprehensively assess masticatory function in maxillectomy patients with functioning removable prostheses. Their general and oral profiles, the measurement values of their oral functions, including masticatory function, and the history of tumor therapy were extracted from medical charts. The correlations of masticatory function with numerical data and the effects of tumor therapy-related factors on masticatory function were evaluated. In addition, a stepwise conditional logistic regression analysis was performed to identify the potential predictive factors comprehensively. The data from 55 maxillectomy patients revealed that the median value of masticatory function (138.0 mg/dL) was higher than the threshold (100.0 mg/dL) based on the concept of oral hypofunction. Moderate correlations of masticatory function with the number of remaining teeth, the number of functioning occlusal supports, and maximum occlusal force were found, as well as a weak correlation with maximum tongue pressure. These variables also showed statistically significant coefficients (p < 0.01). No significant effect of each tumor therapy-related factor on masticatory function was detected. A logistic regression analysis identified the number of functioning occlusal supports as a significant predictive factor. These results implied the crucial interactions of masticatory function with various factors and the specificities of maxillectomy patients.

Ex Vivo Preservation of Ovine Periosteum Using a Perfusion Bioreactor System

Periosteum is a highly vascularized membrane lining the surface of bones. It plays essential roles in bone repair following injury and reconstruction following invasive surgeries. To broaden the use of periosteum, including for augmenting in vitro bone engineering and/or in vivo bone repair, we have developed an ex vivo perfusion bioreactor system to maintain the cellular viability and metabolism of surgically resected periosteal flaps. Each specimen was placed in a 3D printed bioreactor connected to a peristaltic pump designed for the optimal flow rates of tissue perfusate. Nutrients and oxygen were perfused via the periosteal arteries to mimic physiological conditions. Biochemical assays and histological staining indicate component cell viability after perfusion for almost 4 weeks. Our work provides the proof-of-concept of ex vivo periosteum perfusion for long-term tissue preservation, paving the way for innovative bone engineering approaches that use autotransplanted periosteum to enhance in vivo bone repair.

Outcomes of immediate dental implants in vascularised bone flaps for mandibular reconstruction

BACKGROUND

The aim of this study is to assess the outcomes of immediate implant placement for dental rehabilitation following mandibular reconstruction with vascularised bone flaps in a single Australian tertiary cancer centre.

METHODS

A retrospective analysis of patients who underwent immediate dental implant or delayed placement in vascularised bone flaps was performed. Primary outcome measures assessed included the number of implants placed, operative time, complication rates, time to radiotherapy initiation, dental rehabilitation rates and time to dental rehabilitation.

RESULTS

In total, 187 dental implants were placed in 52 patients, of which 34 patients underwent immediate implant placement and 18 had delayed implant placement. There were no significant differences in the postoperative complication rate (32% immediate vs. 33% delayed, P = 0.89) or time to postoperative radiotherapy (median 42 days immediate vs. 47 days delayed, P = 0.24). Dental rehabilitation was achieved in 62% of the immediate cohort versus 78% of the delayed cohort. The time to be fitted with a dental prosthesis was significantly shorter in the immediate cohort (median 150 days immediate vs. 843 days delayed, P = 0.002).

CONCLUSIONS

The placement of immediate dental implants at the time of primary reconstruction of the mandible is a safe procedure and facilitates timely dental rehabilitation.

Construct and discriminant validity testing of the FACE-Q Head and Neck Cancer Module for assessing speech and swallowing outcomes for patients undergoing maxillectomy or mandibulectomy

BACKGROUND

The FACE-Q H&N is a patient reported outcome measure covering multiple constructs for patients with head and neck tumors. Additional testing is needed to determine suitability in assessing speech- and swallowing-related quality of life and function.

METHODS

FACE-Q H&N, The M. D. Anderson Dysphagia Inventory (MDADI), and Speech Handicap Index (SHI) scores were collected from two patient cohorts who had undergone jaw reconstruction. Construct validity was assessed using convergent validity testing and known groups testing to assess discriminant validity.

RESULTS

A priori hypotheses testing demonstrated strong correlations (ρ > 0.6, p < 0.05) between FACE-Q H&N eating and drinking, swallowing and eating distress scales with MDADI subscales, and between FACE-Q H&N speech function and distress scales and the SHI. Known groups testing demonstrated all instruments could delineate outcomes among patients who had radiation, advanced tumors, and tracheostomy.

CONCLUSION

The FACE-Q H&N may be an alternative for the SHI and MDADI in this patient cohort.

Virtual reality digital surgical planning for jaw reconstruction: a usability study

BACKGROUND

Digital surgical planning (DSP) has revolutionized the preparation and execution of the management of complex head and neck pathologies. The addition of virtual reality (VR) allows the surgeon to have a three-dimensional experience with six degrees of freedom for visualizing and manipulating objects. This pilot study describes the participants experience with the first head and neck reconstructive VR-DSP platform.

METHODS

An original VR-DSP platform has been developed for planning the ablation and reconstruction of head and neck pathologies. A prospective trial utilizing this platform involving reconstructive surgeons was performed. Participants conducted a simulated VR-DSP planning session, pre- and post-questionnaire as well as audio recordings allowing for qualitative analysis.

RESULTS

Thirteen consultant reconstructive surgeons representing three surgical backgrounds with varied experience were recruited. The majority of surgeons had no previous experience with VR. Based on the system usability score, the VR-DSP platform was found to have above average usability. The qualitative analysis demonstrated the majority had a positive experience. Participants identified some perceived barriers to implementing the VR-DSP platform.

CONCLUSIONS

Virtual reality-digital surgical planning is usable and acceptable to reconstructive surgeons. Surgeons were able to perform the steps in an efficient time despite limited experience. The addition of VR offers additional benefits to current VSP platforms. Based on the results of this pilot study, it is likely that VR-DSP will be of benefit to the reconstructive surgeon.

Quality of life in patients with cancer-related Brown IIb maxillary defect: A comparison between conventional obturation rehabilitation and submental flap reconstruction

OBJECTIVES

The purpose of this retrospective study was to compare the differences in quality of life (QOL) outcomes between the conventional obturator prostheses (COP) and the pedicled submental artery island flap (SAIF) in the reconstruction of Brown IIb maxillary defects.

MATERIALS AND METHODS

The QOL of 116 eligible patients who had a lapse ≥ 12 months after the cancer-related maxilla ablation was evaluated by the University of Washington quality of life scale (UW-QOL), Performance Status Scale for Head and Neck (PSS-HN), and Obturator Functioning Scale (OFS).

RESULTS

Patients in the SAIF group reported statistically and clinically significant higher overall QOL scores but lower chewing scores in the UW-QOL scale when compared with those in the COP group (P < 0.05). Clinically significantly higher scores were also observed in the recreation and anxiety domains in the UW-QOL scale for the SAIF group, but there was no statistical significances. The COP group reported more complaints about the nasal leakage when swallowing and the shape of the upper lip, and had a stronger willingness to avoid family or social events in the OFS (P < 0.05).

CONCLUSIONS

For patients with Brown IIb defects, SAIF reconstruction can achieve reduced nasal leakage when swallowing, improved upper-lip contour, increased social activity, and superior overall QOL than COP. The inferior chewing function in the SAIF group indicated the need for dental rehabilitation with a conventional denture or osseointegrated implants.