Tissue engineering for otorhinolaryngology-head and neck surgery

The effectiveness and safety of growth factors in the treatment of tympanic membrane perforations: a systematic review and meta-analysis of randomized controlled trials

PURPOSE

To determine the clinical efficacy and safety of growth factors in the treatment of tympanic membrane (TM) perforations from randomized controlled trials (RCTs).

METHODS

Databases, including PubMed, EMBASE, Cochrane library, Ebsco, Ovid, Scopus, and Web of Science, were searched for articles in any language about studies on the treatment of TM perforations with growth factors. Inclusion criteria were: (1) randomized controlled trials (RCTs); (2) only patients with TM perforations included; and (3) any kinds of growth factors or related products were used as an intervention. Exclusion criteria were: (1) study was not reported as a full paper, only as an abstract; (2) review studies and case reports; and (3) an inability to extract valid data. Outcomes of interest included perforation closure rate, closure time, hearing improvement, and complications.

RESULTS

Nineteen RCTs with a total of 1335 participants were included. Growth factors effectively increased the rate of perforation closure [risk ratio (RR): 1.21 95% confidence interval (1.12, 1.30), p < 0.01] and shortened closure time [mean difference (MD): - 16.71 (- 22.74, - 10.15), p < 0.01]. There was no significant difference in hearing improvement [MD: 0.10 (- 0.50, 0.70), p = 0.74] or complications [RR: 1.49 (0.96, 2.32), p = 0.07] between the growth factor intervention group and the control group.

CONCLUSION

Growth factors are effective and safe in the treatment of TM perforations. However, better designed clinical trials should be carried out in the future to obtain more robust findings about the effectiveness of growth factors in the treatment of TM perforations.

Advances in regenerative medicine for otolaryngology/head and neck surgery

Head and neck structures govern the vital functions of breathing and swallowing. Additionally, these structures facilitate our sense of self through vocal communication, hearing, facial animation, and physical appearance. Loss of these functions can lead to loss of life or greatly affect quality of life. Regenerative medicine is a rapidly developing field that aims to repair or replace damaged cells, tissues, and organs. Although the field is largely in its nascence, regenerative medicine holds promise for improving on conventional treatments for head and neck disorders or providing therapies where no current standard exists. This review presents milestones in the research of regenerative medicine in head and neck surgery.

Current concepts and novel techniques in the prosthodontic management of head and neck cancer patients

'The face is the mirror of the mind', so said St Jerome. Patients affected by head and neck cancer have to deal not only with the effects of the disease but also with the effects of the treatment for the disease. This is one cancer which is literally and figuratively 'in your face'! And it is a disease which is difficult to hide. This article attempts to summarise head and neck cancer and its treatment modalities as well as the effects of treatment and the defects it creates. It will also attempt to explore and elaborate on the novel prosthodontic management techniques in advanced jaw reconstruction and extraoral anatomical defects. The concept of functional assessment and rehabilitation in head and neck cancer patient management will also be briefly explained.

Mechanical, Cellular, and Proteomic Properties of Laryngotracheal Cartilage

The larynx sometimes requires repair and reconstruction due to cancer resection, trauma, stenosis, or developmental disruptions. Bioengineering has provided some scaffolding materials and initial attempts at tissue engineering, especially of the trachea, have been made. The critical issues of providing protection, maintaining a patent airway, and controlling swallowing and phonation, require that the regenerated laryngotracheal cartilages must have mechanical and material properties that closely mimic native tissue. These properties are determined by the cellular and proteomic characteristics of these tissues. However, little is known of these properties for these specific cartilages. This review considers what is known and what issues need to be addressed.

Human Adipose-Derived Mesenchymal Stem Cells for Osseous Rehabilitation of Induced Osteoradionecrosis: A Rodent Model

Objective Human adipose-derived mesenchymal stem cells (ADSCs) were used to rehabilitate bone damaged by osteoradionecrosis (ORN) in an established animal model. Study Design Prospective animal study. Setting Academic department laboratory. Subjects and Methods After institutional review board and Institutional Animal Care and Use Committee approval, 24 athymic nude rats were divided into 5 groups: 4 groups irradiated (20 Gy) by brachytherapy catheter placed at the left hemimandible and 1 mock irradiation control (n = 4). For all groups, ORN was initiated by extraction of the central molar 1 week later. After 28 days, animals (n = 5/group) received injection at the extraction site with saline (SAL), ADSCs, platelet-rich plasma and collagen (PRP/COL), or ADSCs + PRP/COL. Rats were sacrificed 28 days later and their mandibles harvested for histopathology analysis (osteoblasts, osteoclasts, and fibrosis) and bone volume measurement using 3-dimensional micro-computed tomography. Results All but 1 rat survived the experiment period (23/24). Radiographic and histological analysis revealed 60% bone loss in the SAL group compared with the nonirradiated control. Injection of ADSCs increased jaw region bone volume by up to 36% ( P < .01). All experimental groups (ADSC, PRP/COL, and ADSC + PRP/COL) showed dramatically decreased osteoclast counts ( P < .001) while injection of PRP/COL with or without ADSCs increased osteoblasts. Increased fibrosis was observed after ADSC injection ( P < .05). Conclusion The application of human ADSCs to an induced mandibular osteoradionecrosis model in athymic rats results in increased deposition or preservation of bone, demonstrated both histologically and radiographically. This offers an encouraging possible treatment option for translational research in this difficult disease.

Regenerative Medicine Build-Out

Regenerative technologies strive to boost innate repair processes and restitute normative impact. Deployment of regenerative principles into practice is poised to usher in a new era in health care, driving radical innovation in patient management to address the needs of an aging population challenged by escalating chronic diseases. There is urgency to design, execute, and validate viable paradigms for translating and implementing the science of regenerative medicine into tangible health benefits that provide value to stakeholders. A regenerative medicine model of care would entail scalable production and standardized application of clinical grade biotherapies supported by comprehensive supply chain capabilities that integrate sourcing and manufacturing with care delivery. Mayo Clinic has rolled out a blueprint for discovery, translation, and application of regenerative medicine therapies for accelerated adoption into the standard of care. To establish regenerative medical and surgical service lines, the Mayo Clinic model incorporates patient access, enabling platforms and delivery. Access is coordinated through a designated portal, the Regenerative Medicine Consult Service, serving to facilitate patient/provider education, procurement of biomaterials, referral to specialty services, and/or regenerative interventions, often in clinical trials. Platforms include the Regenerative Medicine Biotrust and Good Manufacturing Practice facilities for manufacture of clinical grade products for cell-based, acellular, and/or biomaterial applications. Care delivery leverages dedicated interventional suites for provision of regenerative services. Performance is tracked using a scorecard system to inform decision making. The Mayo Clinic roadmap exemplifies an integrated organization in the discovery, development, and delivery of regenerative medicine within a growing community of practice at the core of modern health care.

SIGNIFICANCE

Regenerative medicine is at the vanguard of health care poised to offer solutions for many of today's incurable diseases. Accordingly, there is a pressing need to develop, deploy, and demonstrate a viable framework for rollout of a regenerative medicine model of care. Translation of regenerative medicine principles into practice is feasible, yet clinical validity and utility must be established to ensure approval and adoption. Standardized and scaled-up regenerative products and services across medical and surgical specialties must in turn achieve a value-added proposition, advancing intended outcome beyond current management strategies.