Background/Objectives: Unilateral hearing loss (UHL) is a relatively common disability condition comprising around 20–50% of all congenital hearing loss (HL). The adverse effects of UHL affect the typical development of auditory function with implications for communication, speech and language acquisition, academic development and quality of life. Current literature suggests an early intervention treatment in order to avoid developmental delays, but there is a lack of evidence about the effectiveness and use of hearing devices. The purpose of the present study was to evaluate the benefits of rehabilitative strategies such as hearing aid (HA) and cochlear implant (CI) in UHL children by exploring audiological and parent-reported outcomes. Methods: A total of 18 UHL children, between the ages of 3 and 17, were enrolled in the study designed as a prospective longitudinal study from July 2023 to July 2024. All children were evaluated for speech perception in quiet and noise and subjective benefits before and after rehabilitative treatment with HA in 15 (83.3%) children and with CI in 3 (16.7%) children. Results: The evaluation of audiological outcomes in children with UHL, based on assessment of aided sound field thresholds and speech perception scores assessment versus unaided, shows improvements in audiometric thresholds and how the hearing devices adequately support listening and spoken language. Scores with hearing devices were significantly higher than baseline-only scores when averaging both SSQ and CHILD questionnaires, pointing to an overall rehabilitative benefit. Conclusions: Rehabilitative interventions, particularly HA and CI, offer notable benefits when introduced early, but achieving optimal outcomes requires a multidisciplinary and individualized approach.

Background/Objectives: Mastoid obliteration is being increasingly used to reduce cavity-related morbidity after mastoidectomy. Alongside autologous grafts, synthetic biomaterials and tissue-engineering approaches have emerged as potential alternatives. This systematic review synthesized the clinical and preclinical evidence on biomaterials for mastoid obliteration, focusing on efficacy, safety, biological integration, and translational potential. Methods: A Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)-compliant search of PubMed, Scopus, and Web of Science identified studies published between January 2010 and May 2026. Eligible studies evaluated biomaterials for mastoid obliteration in clinical settings or experimental models. Data on study design, biomaterial type, intervention, outcomes, complications, and biological endpoints were extracted. Risk of bias was assessed using the Risk of Bias in Non-randomized Studies of Interventions (ROBINS-I), Revised Cochrane Risk of Bias Tool for Randomized Trials (RoB 2), and the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE) risk-of-bias tool. Results: Twenty-eight studies were included (19 clinical, 9 preclinical). Clinical evidence supported mastoid obliteration as an effective strategy for improving cavity stability, reducing chronic otorrhea, promoting epithelialization, and aiding cholesteatoma control. Outcomes appeared to depend more on successful cavity elimination than on the superiority of a specific biomaterial. Autologous materials showed reliable and reproducible results, while S53P4 bioactive glass demonstrated comparable effectiveness with additional antibacterial properties. Hydroxyapatite-based materials and allografts showed more variable outcomes. Biologically enhanced approaches, including concentrated growth factors and composite constructs, yielded promising but limited clinical evidence. Preclinical studies indicated that conventional biomaterials are primarily osteoconductive, whereas composite scaffolds, bone morphogenetic protein-2 (BMP-2) delivery systems, and stem cell-based strategies may enhance osteogenesis and tissue integration. However, clinical translation remains limited. Conclusions: Mastoid obliteration is an effective reconstructive strategy whose success depends mainly on stable cavity reduction and adequate epithelial coverage. Autologous materials and S53P4 bioactive glass currently have the strongest clinical support, whereas advanced tissue-engineering approaches require further validation through prospective comparative studies, standardized outcomes, long-term follow-up, and translational research.