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The tympanic membrane (TM), more commonly known as the eardrum, consists of a thin layer of tissue in the human ear that receives sound vibrations from outside of the body and transmits them to the auditory ossicles. The TM perforations (TMPs) are a common ontological condition, which in some cases can result in permanent hearing loss. Despite the spontaneous healing capacity of the TM to regenerate in the majority of cases of acute perforation, chronic perforations require surgical interventions. However, the disadvantages of the surgical procedure include infection, anesthetic risks, and high failure of graft patency. The tissue engineering strategy, which includes the applications of a three-dimensional (3D) scaffold, cells, and biomolecules or a combination of them for the closure of chronic perforation, has been considered as an emerging treatment. Using this approach, emerging products are currently under development to regenerate the TM structure and its properties. This research aimed to highlight the problems with the current methods of TMP treatment, and critically evaluate the tissue engineering approaches, which may overcome these drawbacks. The focus of this review is on recent literature to critically discuss the emerging advanced materials used as a 3D scaffold in the development of a TM with cellular engineering, biomolecules, cells, and the fabrications of the TM and its pathway to the clinical application. In this review, we discuss the properties of TM and the advantages and disadvantages of the current clinical products for repair and replacement of the TM. Furthermore, we provide an overview of the in vitroand preclinical studies of emerging products over the past 5 years. The results of recent preclinical studies suggest that the tissue engineering field holds significant promise.

The tympanic membrane (TM) integrity is necessary for our normal hearing function. TM perforations pose significant morbidities such as middle ear infection, recurrent otorrhea, hearing loss, and acquired cholesteatoma. Myringoplasty is commonly performed to repair chronic perforations; although various grafts and materials have been utilized to promote TM regeneration, all have associated restrictions. This study aimed to prepare and evaluate the efficacy and feasibility of a tissue-engineered patch based on silk fibroin and gelatin (SF-GT) to improve regeneration. A casting technique was used to make the SF-GT films, using 0–30 v/v% GT, as it is shown that films are remarkably efficient for TM regeneration, easy to mass produce and cheap to make. The surface morphology (SEM), chemical structure (FTIR), crystallinity (XRD), mechanical strength (tensile test), water uptake and in vitrodegradation, and cellular biocompatibility (MTT and scratch) were investigated for SF-GT films, and the optimal patch was chosen based on the results (SF-30GT). SF-30GT was used for in vivostudies in a rat model with TM perforations to induce TM regeneration. The morphology of the TM was assessed at days 0, 3, 5, 7, 9 and 11 post-implantation using otoscopy and functional outcomes by auditory brainstem responses (ABRs). This study indicates that compared with the control group (spontaneous healing), the SF-30GT scaffold was more effective in promoting early TM regeneration (complete healing at day 7) and normal hearing (back to 20 dB after healing), suggesting that this scaffold can be a potential substitute for clinical use.