## 1 Introduction  
Hearing loss affects a significant portion of the population, with projections indicating that nearly 2.5 billion people may experience some degree of hearing loss by 2050. The prevalence underscores the critical need for accessible and effective hearing care servicesworldwide [1]. In fact, hearing loss leads to a lower quality of life and social, communicative, and emotional isolation, leading, in some cases, to depression [2; 3]. Understanding the etiology behind the need for hearing aids involves exploring the different pathologies that lead to hearing loss. Hearing loss can be defined as conductive or sensorineural depending on the causes of hearing loss, as explained by [PERSON] [4]. Depending on the severity of hearing loss, treatment options include hearing aids, cochlear implants, and other assistive technologies. Hearing loss assessment involves detailed audiometric testing to accurately diagnose the type and extent of hearing loss. This assessment includes pure-tone audiometry and tympanometry, along with Rinne and Weber tests, to distinguish between conductive and sensorineural hearing loss components [5]. A hearing aid is a device that is used in the rehabilitation of various types of deafness or hearing loss or for hearing protection purposes. Recent studies have revealed the potential of audiology, mainly through rhythmic RAS and music therapy, by hearing aid use. By integrating RAS and music therapy into their patients' treatment plans, healthcare professionals have discovered enhanced improvements in the quality of life and functional abilities of individuals with cognitive, degenerative, or motor disabilities compared to conventional therapies [6; 7; 8; 9; 10]. Regardless of hearing aid use purpose, the commitment to customized solutions across the range of audiology underlines the importance of personalized care to achieve the best possible results for patients and users of all ages and with different pathologies or specific needs, such as pediatrics applications, risk of hearing damage environments, military purposes, musicians, and others [11; 10; 12; 13; 14]. The selection of the style, type of hearing aid, material and design of the ear mold, and print quality are key factors in personalizing the adaptation of the hearing aid to the individual's needs, ensuring both performance and comfort [11; 15; 16; 17]. Nevertheless, these choices also depend on factors such as the extent of ear loss, the individual's preference, anatomical considerations, and the audiologist's recommendations [16]. The goals of a custom hearing aid include ensuring adequate acoustic sealing, in-ear retention, acoustic signal modification, comfort, and pleasing aesthetics. These are the advantages of custom hearing aids compared to universal parts. This paper presents a low-cost direct digital manufacturing methodology for obtaining customized hearing aids. A video otoscope prototype with an integrated scanner was designed and built for this purpose. This video otoscope will also allow the real-time acquisition of external ear canal (EEC) images, leading to quick diagnoses and evolution monitoring of hearing pathologies through AI methodologies. The use of AI for diagnosing and recognizing ear pathologies has grown significantly in recent years. With the advancement of machine learning techniques and deep neural networks, it has become possible to create systems capable of accurately identifying various hearing conditions, often with results comparable to those of healthcare professionals. These software programs typically use medical images, such as audiograms, MRIs, CT scans, or even acoustic signals, such as otoacoustic emissions, to automatically diagnose conditions such as hearing loss, e.g., otitis, and other diseases characteristic of the inner ear. Among the most relevant applications, convolutional neural networks (CNNs) stand out, as they have been widely used for analyzing medical images.