Hearing Impairment in Oral Submucous Fibrosis: A Systematic Review

Abstract

Background: With serious oral and systemic implications, oral submucous fibrosis (OSMF) is a crippling disorder that is common in some areas, especially among areca nut chewers. A thorough investigation of the relationship between OSMF and hearing impairment is necessary due to the growing evidence that, despite its well-established effects on dental health, there may be a connection. Aim: To investigate the association between OSMF and hearing impairment, particularly the mechanisms behind Eustachian tube dysfunction (ETD) and auditory dysfunction in OSMF patients. Methodology: This systematic review aimed to assess the association between hearing impairment and OSMF using the PICOS framework. A comprehensive search of 1137 articles published between 2015 and 2024 across various databases was conducted, resulting in 18 studies meeting the inclusion criteria. Data on population demographics, audiological assessments, and outcomes were extracted independently by 3 reviewers. The quality of the included studies was evaluated using the Cochrane Risk of Bias Tool and the Newcastle–Ottawa Scale. Risk of bias assessments was conducted to categorize studies as low, moderate, or high risk. Results: The review identified 18 studies examining the link between OSMF and hearing impairment, revealing a significant correlation between OSMF severity and hearing loss. Patient-reported hearing issues ranged from 27.69% to 76.7%. Conductive hearing loss was prevalent, particularly in advanced OSMF stages. Most studies employed pure tone audiometry and tympanometry, highlighting ETD as a common contributor. Quality assessments indicated that most studies had good methodological rigor, with several rated as very good, underscoring the need for comprehensive evaluations in understanding the audiological implications of OSMF. Conclusion: There is a substantial association between OSMF and hearing loss, particularly through ETD. Multidisciplinary management and early audiological screening are essential for improving outcomes in OSMF patients.

Introduction

Oral submucous fibrosis (OSMF) is a chronic, debilitating condition characterized by progressive fibrosis of the oral mucosa and submucosal tissues, often associated with the habitual use of areca nut and other irritants. This condition poses not only aesthetic and functional challenges but can also lead to significant health complications, including hearing impairment. The relationship between OSMF and auditory function has garnered increasing attention in recent years, given that the oral cavity and the ear share anatomical and physiological connections. Specifically, the Eustachian tube, which links the middle ear to the nasopharynx, plays a crucial role in maintaining middle ear pressure and is affected by conditions involving surrounding structures, such as OSMF.^1,2 The extent of hearing impairment in patients with OSMF can vary widely and has been shown to correlate with the severity of the disease. Studies have indicated that changes in the structure and function of the Eustachian tube due to fibrosis may lead to Eustachian tube dysfunction (ETD), causing a chain reaction that affects middle ear function and results in auditory deficits.^3-5 Understanding the mechanisms underlying these auditory changes is vital for clinicians to provide comprehensive care for OSMF patients, who may suffer from both oral and auditory complications.

Hearing Impairment in OSMF

The degree of OSMF and its possible effects on Eustachian tube function are the main factors influencing the multifactorial nature of hearing impairment in these patients. Numerous studies have been conducted on the relationship between OSMF and auditory deficiencies, and the results show a complex interaction between the disease’s course and hearing efficiency. Studies have demonstrated that individuals frequently have a reduction in hearing efficiency as OSMF advances through different clinical grades. The clinical grading of OSMF and hearing impairment levels were found to be significantly correlated in a study by Shah and Lunagariya, ¹ highlighting the importance of early diagnosis and treatment of both disorders. Similarly, individuals with more advanced stages of OSMF showed more noticeable hearing impairments, as noted by Srivastava et al, ⁶ indicating a direct correlation between the degree of oral fibrosis and auditory function. These results highlight the need for routine evaluations of the patient’s hearing in individuals with OSMF, since prompt management could prevent additional loss of hearing.

Impact of ETD

The pathological modifications to the oral cavity and its surrounding tissues cause changes to the structural integrity and functionality of the Eustachian tube, which can cause ETD. The Eustachian tube is essential for maintaining the proper balance of air pressure in the middle ear, and its blockage or malfunction can have a domino effect on the health of the auditory system. Research has indicated that alterations in the soft tissue encircling the Eustachian tube may result in compromised middle ear ventilation and drainage, hence generating an environment with negative pressure. This malfunction has the potential to impede auditory transduction, which in turn can result in conductive hearing loss (CHL). This connection was further clarified by Devi et al, who discovered a significant prevalence of hearing impairments in OSMF patients and connected these impairments to the clinical and histological severity of the illness. ³ Rathod et al found trace element levels in OSMF patients and linked these to hearing loss, which complicated the picture of what influences auditory deficiencies in this group. ⁴ Based on available data, the best patient therapy may need a multidisciplinary strategy that addresses both the oral and auditory elements of OSMF.

Audiological Assessment and Management Strategies

Comprehensive audiological examinations are necessary to identify hearing impairment in patients with OSMF. Regular audiometric examinations, such as tympanometry and pure-tone audiometry (PTA), are crucial for identifying the presence and severity of hearing loss and for assisting medical practitioners in developing customized treatment regimens. Swain and Das underlined the significance of these evaluations, emphasizing that prompt treatments to enhance auditory outcomes might be made possible by early detection of hearing impairment. ⁷ Treatment plans for individuals with hearing loss caused by OSMF may involve medications like steroids or nasal decongestants that try to treat ETD. To improve hearing and restore middle ear function in more severe cases, surgical treatments such as myringotomy or tympanostomy tube installation may be necessary. Incorporating ENT doctors into the care of patients with OSMF can offer important insights into the challenges associated with managing both oral and auditory problems.

ETD and Its Effects on Hearing

Numerous research that has investigated the relationship between oral and auditory health have shown that ETD is a common side effect of OSMF. A disruption in the Eustachian tube’s function can result in a variety of auditory difficulties, such as pain, a fullness sensation, and reduced hearing. The Eustachian tube is an essential channel for equalizing air pressure in the middle ear. Siddiqui et al’s research found that people with OSMF often had undetected ETD, which emphasizes the importance of careful audiometric evaluations in this patient population. ⁸ Additionally, a variety of ETD symptoms, such as pressure in the ears and ear pain, are frequently reported by patients with OSMF, which can adversely affect their quality of life, quite significantly. Chandran and Aswath’s tympanometric studies provide additional evidence that patients with OSMF frequently have altered tympanometric patterns, which are suggestive of middle ear dysfunction. ⁵ These results highlight how crucial it is to take auditory impairment into account while managing OSMF overall because doing so can enhance patient outcomes.

Implications of ETD in OSMF

The relationship between Eustachian tube function and OSMF can have significant effects on how patients are managed. According to Rathod et al, patients with OSMF may experience chronic middle ear issues because of reduced Eustachian tube function. This means that treating OSMF requires a multidisciplinary strategy that considers both the oral condition and its systemic implications. ⁴ To guarantee that patients receive comprehensive care, this comprehensive management method may involve coordination between audiologists, otolaryngologists, and oral health specialists. It is possible that underlying inflammatory processes that impact the Eustachian tube and oral cavity are related to the link between OSMF and ETD. The localized inflammation caused by the fibrosis characteristic of OSMF may exacerbate the symptoms of ETD. By allowing doctors to customize interventions to address oral and auditory difficulties, these processes can eventually improve patient outcomes.

Auditory Impairment in OSMF: Pathophysiology and Management

Finding and treating hearing deficits in individuals with OSMF requires routine auditory evaluations, particularly considering the high incidence of ETD linked to the illness. By enabling the early identification of auditory deficiencies, instruments such as tympanometry and PTA enable focused treatments such as nasal decongestants, balloon dilatation of the Eustachian tube, or other treatments meant to restore normal auditory tube function.^3,5 When the underlying pathophysiology of OSMF is examined, it becomes clear how fibrotic alterations in the oral mucosa might impact nearby structures, such as the tissues and muscles that support the Eustachian tube. ETD and hearing impairment could result from this disturbance. Neurovascular variables, vascular alterations, and inflammatory pathways may intensify this dysfunction and lead to CHL.^1,2 Patients with OSMF may experience additional complications with their auditory health due to secondary processes, such as infections or autoimmune reactions. ⁴ Raising patient awareness about the auditory complications of OSMF can result in earlier diagnosis and intervention, ultimately improving their quality of life. The complicated effects of OSMF on auditory health must be managed with regular audiometric examinations and patient education. ⁷

The purpose of this systematic review was to examine the relationship between auditory dysfunction and OSMF, with a particular emphasis on ETD and hearing loss in OSMF patients. Examining the pathophysiological pathways is the goal, along with the effects of inflammation, fibrotic changes. The study assessed the effectiveness of diagnostic instruments like tympanometry and PTA in early identification of hearing impairment. It also investigated potential therapies for auditory impairments, such as nasal decongestants and balloon dilatation of the Eustachian tube. The objective of the study was to enhance awareness, early diagnosis, and management of auditory problems in OSMF patients and secondary variables such as infections and vascular abnormalities.

Methodology

Research Question

The primary research question guiding this systematic review was: “Is there a significant association between hearing impairment and OSMF, and what are the potential mechanisms behind this association?”

Time Frame of the Study

2015 to 2024 (10 years).

PICOS Framework

• Population (P): Patients diagnosed with OSMF, which can potentially extend to structures related to hearing.

• Intervention (I): The core investigation centered on hearing impairment, including the assessment of changes in hearing efficiency, the functionality of the Eustachian tube, and any alterations in middle ear function.

• Comparison (C): A comparison was made between different groups, including patients without OSMF and those with varying grades of the condition.

• Outcomes (O): The primary outcomes studied were the presence and degree of hearing loss, abnormalities in middle ear function, and dysfunction of the Eustachian tube.

• Study Design (S): The review included a variety of study designs such as clinical studies, cross-sectional analyses, and case–control studies.

Search Strategy

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria were followed in this systematic review to guarantee an exhaustive and open procedure. A comprehensive search plan was created to find pertinent material across a range of databases, including Google Scholar, PubMed, Embase, Scopus, Web of Science, and the Cochrane Library. To find clinical trials and gray literature, other specialist databases were examined, including ClinicalTrials.gov and MedlinePlus. Free-text keywords and Medical Subject Headings (MeSH) terms were used to do the search. By using the Boolean operators AND, OR, and NOT to narrow down the search, studies about hearing impairment and OSMF may be found. The search phrases and keywords used comprised “oral submucous fibrosis,” “hearing loss,” “hearing impairment,” “Eustachian tube dysfunction,” “middle ear function,” “tympanometry,” “auditory efficiency,” “trace elements in OSMF,” “hearing evaluation in OSMF,” “conductive hearing loss,” “fibrosis-related hearing deficits,” “audiological assessment,” “otological manifestations in OSMF,” “nasopharyngeal involvement in OSMF,” along with “ETD in fibrotic conditions.” Boolean operators were used to combine terms in the following ways to ensure comprehensive coverage: (“trace elements” OR “fibrosis”); (“Eustachian tube dysfunction” OR “ETD”) AND (“middle ear function” OR “auditory efficiency”); (“oral submucous fibrosis” OR “OSMF”) AND (“hearing loss” OR “hearing impairment”). The databases were searched for articles published between 2000 and 2024. Filters were applied to include studies in English and those involving human subjects. Additionally, the reference lists of all the included articles were screened manually to identify any further studies that may be relevant, ensuring a thorough capture of the literature.

Selection Criteria

Studies involving human subjects diagnosed with OSMF, including clinical studies, case–control studies, and observational studies that specifically measured middle ear function, Eustachian tube function, or hearing efficiency in OSMF patients, met the inclusion criteria for this systematic review. Only research that was published between 2015 and 2024 in peer-reviewed publications was considered. For inclusion in the review, studies were required to be published in English. Moreover, only investigations involving adult populations aged 18 years and older were included to ensure demographic homogeneity. Additionally, studies were required to classify the severity of OSMF using standardized grading systems, such as the Khanna and Andrade classification, ⁹ to facilitate consistent comparisons across findings. Studies using animal models, case reports, editorials, and letters to the editor were all excluded because they lacked the strong evidence required for a systematic review. Research without unambiguous evaluations of hearing impairment or quantifiable results pertaining to auditory function were likewise disregarded. Moreover, articles written in languages other than English were excluded from consideration for inclusion.

Data Extraction, Synthesis, and Quality Assessment

From a total of 1137 screened articles, 18 met the inclusion criteria for this review (Figure 1). Data extraction was independently performed by 4 reviewers (C.K., A.D., K.K., A.B.), focusing on study characteristics, population demographics, hearing evaluation methods, and outcomes related to hearing impairment in OSMF patients. Discrepancies were resolved through discussion or consultation with a fourth reviewer. Both narrative and quantitative approaches were employed to synthesize findings. Quality assessment utilized the Cochrane Risk of Bias Tool for randomized controlled trials and the Newcastle–Ottawa Scale (NOS) for non-randomized studies, grading studies based on selection criteria, comparability, and outcome metrics. A detailed table documented individual NOS scores, emphasizing adjustments for confounding factors such as age, gender, and lifestyle habits (eg, smoking, alcohol use). Studies with lower comparability scores due to insufficient control of confounders were flagged and their implications discussed. K.K. handled quality assessment and dispute resolution, C.K. led data synthesis, and A.D. and A.B. ensured data accuracy.

Figure 1.

PRISMA flowchart for the review.

Risk of Bias Assessment

Every study that was part of the review had its risk of bias carefully evaluated. Selection bias, performance bias, detection bias, attrition bias, and reporting bias were among the criteria used in the assessment. The Cochrane Risk of Bias Tool was utilized for randomized trials, and the NOS was used for non-randomized research to assess each study. The risk of bias in studies was rated as low, moderate, or high. Sensitivity analyses were incorporated into the bias mitigation process to eliminate high-bias studies from pooled results to improve reproducibility. Reevaluating flagged research using more stringent NOS criteria was done in addition to employing a consensus approach to resolve disputes. While K.C., C.S., and A.D. studied reporting and performance biases, K.K. and A.B. evaluated selection and detection biases. Bias rating disagreements were settled by a consensus or a discussion.

Results

This study did not conduct a meta-analysis because of the substantial heterogeneity seen in the included trials. The total impact size of the link between OSMF and hearing impairment could not be quantitatively analyzed due to variations in methods, diagnostic instruments, participant selection criteria, and outcome measures amongst research. Thus, instead of combining data into a single statistical model, a systematic review was carried out to highlight important patterns and connections and summarize the results from the numerous investigations.

Prevalence and Correlation Between OSMF Severity and Hearing Loss

Studies examining the association between hearing impairment and OSMF severity are compiled in Table 1. Hearing loss was repeatedly found to be significantly correlated with the severity of OSMF, with patient-reported hearing problems ranging from 27.69% to 76.7%. Shah and Lunagariya ¹ discovered that 30% of people had hearing loss, but Devi et al ³ and Jha et al ¹⁰ revealed that 44% and 46% of their respective cohorts had hearing impairment. According to Chandran and Aswath ⁵ and Harkare et al, ¹¹ ETD was frequently found to be a contributing factor to these auditory abnormalities. Studies primarily employed PTA and tympanometry as audiological assessment methods. Singh et al ² and Srivastava et al ⁶ stressed the importance of early detection and management of hearing impairment in OSMF patients to improve clinical outcomes.

Table 1.

Characteristics of Included Studies.

Study (author, year)	Study design	Sample size	OSMF grade (I–IV)	Duration of OSMF (years)	Duration of hearing loss (years)	Percentage of patients reported hearing issues	Audiological assessment	Primary outcome
Devi et al (2015) 3	Cross-sectional	40 (OSMF group) and 10 (control group)	Group A (≥35 mm), Group B (30-35 mm), Group C (20-30 mm), Group D (<20 mm)	Not specified	Not specified	44% of ears (mild conductive or sensorineural loss)	PTA (ALP 2100 clinical audiometer)	Significant association between OSMF severity and hearing loss, especially in Groups C and D
Chandran and Aswath (2016) 5	Case–control study	45	Stage III (n = 15) Stage IV (n = 15) Control (n = 15)	Not specified	Not specified	76.7% (Stage IV), 43.3% (Stage III)	Audiometry and tympanometry	Function of Eustachian tube affected as OSMF progressed
Sowbhagya et al (2016) 12	Cross-sectional study	40 patients	I (1), II (1), III (15), IV (23)	Not specified	Not specified	35% (mild hearing loss), 6.3% (moderate hearing loss)	PTA and tympanometry	OSMF can cause hearing deficits; significant tympanometric changes noted
Kumar (2018) 13	Case–control	40 OSMF patients	I (1), II (1), III (16), IV (22)	Not specified;	Not specified;	Approximately 41.3% reported hearing impairment	Impedance audiometry; tested low frequency (226 Hz); 53% showed no shift in compliance peaks	Significant difference in middle ear pressure (P = .000) between OSMF patients and controls; auditory tube dysfunction noted
Shah et al (2020) 1	Observational study conducted in a clinical setting	30 patients with OSMF	- Grade I (Early OSMF): 10 patients - Grade II (Moderate OSMF): 10 patients - Grade III (Severe OSMF): 10 patients - Grade IV: Not applicable (not included in the study)	Not specified	Not specified	30% of patients reported hearing loss (from 7 out of 30)	PTA	To evaluate Eustachian tube function in OSMF patients and correlate it with the clinical stages of the disease and hearing loss
Swarup et al (2020) 14	Cross-sectional study	25	Mild (Group A & B), Severe (Group C & D)	Not specified	Not specified	40% in severe cases (Group S)	PTA	Significant association between advancing OSF stages and hearing loss (P = .026)
Roy et al (2020) 15	Prospective study	20	II and III	Not specified	Not specified	30% tested positive for hearing deficit (audiometry and tympanometry)	Audiometry and tympanometry	Post-surgical improvement in mouth opening and Eustachian tube function, leading to better middle ear function. Significant improvement observed at 1- and 3-months post-op
Harkare et al (2021) 11	Cross-sectional study	121 patients	I: 112 (100%) II: 66 (87.88%) III: 44 (11.36%) IVA: 12 (0%) IVB: 8 (0%)	Not specified	Not specified	27.69% (Poor Eustachian tube function)	PTA, tympanometry	Significant correlation between OSMF severity and ETD, leading to hearing impairment
Jha et al (2021) 10	Cross-sectional	100 (50 OSMF cases, 50 control)	I-IV	Not specified	Not specified	46% (36% CHL, 10% sensorineural hearing loss)	PTA, tympanometry	OSMF is associated with CHL, primarily due to ETD
Desai et al (2021) 16	Prospective study	40	I-IV	3-5 years	Not reported	40% (75% mild, 25% moderate CHL)	PTA, tympanometry	40% of patients had CHL
Singh et al (2022) 2	Prospective study	200 (100 OSMF, 100 controls)	I: 16% II: 24% III: 38% IV: 22%	Not specified	Not specified	39% of OSMF patients exhibited CHL	PTA, impedance audiometry	Significant correlation between OSMF severity and hearing impairment, with higher grades showing greater prevalence of hearing loss
Sriram et al (2023) 17	Cross-sectional study	40	Group A (≥35 mm): 12 (30%) Group B (25-35 mm): 19 (47.5%) Group C (15-25 mm): 5 (12.5%) Group D (2-15 mm): 4 (10%)	Not specified	Not specified	40% (16 patients) with hearing loss	PTA	16 patients (40%) had hearing loss; 75% had mild CHL, 25% had moderate CHL
Srivastava et al (2023) 6	Prospective study	60 15 in each group (I-IV)	I–IV	Not specified	Not specified	53.3% in Grade III and IV	PTA	Hearing loss correlated significantly with OSMF grades (P = .001), with a greater prevalence in advanced OSMF stages
Rathod et al (2023) 4	Cross-sectional observational	200	I–IV	1-12	0-5	39%	PTA, tympanometry	Significant association between OSMF grades and hearing loss. Increased hearing impairment with higher OSMF stage
Pottam et al (2023) 18	Cross-sectional	200	I-IV	1-15	0-8	39%	PTA, tympanometry	Significant association between OSMF severity and CHL
Sreepradha et al (2023) 19	Cross-sectional study	40	I: 10, IIA: 10, IIB: 10, IIC: 10	Not specified	Not specified	Increased in OSMF severity; 100% in group I (normal) to 10% in group IIC	Tympanometry and audiometry	Significant hearing impairment associated with the severity of OSMF; CHL most common
Sanwal et al (2023) 20	Cross-sectional study	30 patients	Grade I (Early), Grade II (Moderate), Grade III (Severe)	Not specified	Not specified	30% (combined minimal, mild, and moderate hearing loss)	PTA	Correlation of ETD with OSMF grades
Anoop et al (2024) 21	Cross-sectional study	120 subjects (60 OSMF patients and 60 healthy controls)	OSMF patients were divided into 4 groups based on interincisal mouth opening: - Stage I: 11 patients (>35 mm) - Stage II: 23 patients (25-34 mm) - Stage III: 19 patients (15-24 mm) - Stage IV: 7 patients (<15 mm)	Not specified	Not specified	30.8% (37 out of 120 subjects) reported hearing loss (37 patients with hearing loss out of 120 total patients)	PTA and bone conduction tests	Increased severity of hearing loss with the stage of OSMF, with significant CHL observed in advanced stages of OSMF (P < .001)

Abbreviations: CHL, conductive hearing loss; ETD, Eustachian tube dysfunction; OSMF, oral submucous fibrosis; PTA, pure-tone audiometry.

Symptoms and Audiological Findings

The symptoms of OSMF and how they relate to hearing loss are listed in Table 2. Burning feelings, limited mouth opening, and trouble swallowing were common complaints. The most common kind of hearing loss was found to be conductive. According to Devi et al, ³ 44% of ears had hearing loss, but Chandran and Aswath ⁵ found that patients with Stage IV OSMF had a greater rate of hearing loss (76.7%). Harkare et al ¹¹ and Kumar ¹³ both found a strong correlation between OSMF severity and ETD, indicating that higher levels of auditory impairment may be associated with more severe OSMF.

Table 2.

OSMF Symptoms and Audiological Findings.

Author/year	OSMF symptoms	Type of hearing loss and symptoms	Prevalence of hearing loss	Prevalence of ETD	Audiological test	Tympanometric findings
Devi et al (2015) 3	Burning sensation in the mouth, vesicle formation, recurrent inflammation, difficulty opening mouth, speaking, swallowing, and taste alteration	Mild CHL (most common), mild sensorineural hearing loss, moderate sensorineural hearing loss. Symptoms included difficulty in hearing	44% of ears in OSMF patients showed hearing loss (mild conductive in 39% and mild sensorineural in 4%)	Suggested due to fibrosis of palatal muscles affecting Eustachian tube function; not explicitly quantified in the study	PTA conducted using ALP 2100 clinical audiometer	Not specifically detailed in the study; however, indications suggest ETD may affect tympanic function
Chandran and Aswath (2016) 5	Burning sensation, intolerance to spicy foods, and gradual reduction in mouth opening due to fibrosis	CHL; symptoms include hearing impairment, pain in the ear	76.7% in Stage IV, 43.3% in Stage III	Significant increase in severity of dysfunction with disease progression; correlated with hearing impairment	Audiometry and tympanometry	63.3% of Stage IV showed As curve (sclerosis of tympanic membrane); 46.7% of Stage III had As curve; controls had normal A curve
Sowbhagya et al (2016) 12	Burning sensation in the mouth, vesicles, petechiae, salivation changes, mouth opening difficulties, pain in the ear, nasal twang	CHL (mild to moderate); 58% normal hearing, 35% mild loss, 6.3% moderate loss	Hearing loss observed in 41% of ears in the OSMF group; no hearing loss in control group	Significant correlation with advanced stages of OSMF; type C tympanograms indicated ETD	PTA and tympanometry conducted on all subjects	Type A: 55% (normal), Type As: 16.3%, Type Ad: 8.8%, Type B: 11.3%, Type C: 8.8%. Type C prevalence increases with OSMF stage
Kumar (2018) 13	Soreness of mouth, intolerance to chilies and spicy foods, burning sensation, ulceration of oral mucosa, trismus, difficulty opening mouth, and restricted tongue protrusion	CHL; symptoms include muffled hearing or fullness in the ear	Approximately 41.3% of OSMF patients reported hearing impairment	Statistically significant ETD found in OSMF patients (exact percentage not provided)	ETD was evident in 53% of ears tested (no shift in compliance peaks)	Impedance audiometry (Interacoustic AT235)
Shah et al (2020) 1	- Burning sensation on hot/spicy food - Blanching - Palpable fibrosis of buccal mucosa - Restricted mouth opening (Grade I: 25-35 mm; Grade II: 15-5 mm; Grade III: <15 mm) - Difficulty swallowing, speech issues, nasal voice (in severe cases)	CHL - Minimal (16-25 dB), Mild (26-40 dB), Moderate (41-55 dB) hearing loss was observed - Symptoms include pain in the ear and hearing difficulties due to ETD	30% of patients reported hearing issues (7 out of 30 patients; hearing loss categories included minimal, mild, and moderate)	The study indicated that palatal muscle involvement in OSMF may lead to ETD, but specific prevalence figures were not provided. It was mentioned that fibrosis in over 50% of patients affects Eustachian tube function	PTA was performed to evaluate hearing loss in both ears of all patients	Specific tympanometric findings were not detailed in the study, but it can be inferred that the ETD may lead to tympanic membrane mobility changes, potentially detectable via tympanometry
Swarup et al (2020) 14	Fibrosis of oral mucosa, limited mouth opening, pain, burning sensation, and altered taste	CHL (unilateral and bilateral); symptoms include sensations of fullness, muffled sounds, and ear pain	60% in severe cases (Group S)	Not directly specified, but association with advancing stages of OSF suggests dysfunction	PTA	30% of severe cases showed retraction of the tympanic membrane
Roy et al (2020) 15	- Limited mouth opening (trismus) - Burning sensation in the oral cavity - Fibrosis of the oral mucosa - Difficulty swallowing - Altered taste sensation	- CHL - Symptoms: Difficulty hearing, particularly in noisy environments; sensation of fullness in the ear	Approximately 30% of OSMF patients (Grades II and III) showed hearing deficits (positive audiometric results)	Significant correlation between OSMF severity and ETD; increased severity of ETD with worsening OSMF grades	PTA - Tympanometry for assessing middle ear function and Eustachian tube status	- Preoperative: 47% showed positive tympanometric results - Postoperative: 100% improvement in tympanometric findings observed at 1 and 3 months after surgery
Harkare et al (2021) 11	Oral mucosa stiffening, difficulty in mouth opening, potential extension to the nasopharynx, affecting palatal muscles	CHL (minimal, mild, moderate), symptoms include altered sound perception due to middle ear pressure changes	30.58% (minimal: 8.26%, mild: 10.74%, moderate: 11.58% of ears assessed)	27.69% of patients exhibited poor Eustachian tube function, increasing with OSMF severity	PTA and tympanometry were used for assessment of hearing status and Eustachian tube function	Normal tympanogram (Type A): 74.38% Type B (abnormal): 14.88% Type C (abnormal): 10.74%
Jha et al (2021) 10	Histopathological changes noted in OSMF patients	Hearing impairment observed; types not specified	Not specified	Not specified	Audiological evaluations; specifics not detailed	Findings not specified
Desai et al (2021) 16	Symptoms of OSMF include restricted mouth opening (trismus), burning sensation in the mouth, mucosal changes (whitening, fibrosis), and discomfort while eating	Patients with OSMF commonly experience CHL. Symptoms include difficulty hearing, sensation of fullness in the ear, and sometimes pain or discomfort	40% of OSMF patients reported CHL (75% mild and 25% moderate)	ETD is prevalent among OSMF patients, often linked to fibrosis affecting the palatal and paratubal muscles, leading to impaired Eustachian tube function and middle ear pressure regulation	Audiological assessments typically include PTA and tympanometry, used to evaluate hearing levels and middle ear function, respectively	Tympanometric findings in OSMF patients often indicate middle ear dysfunction, such as reduced compliance or abnormal tympanograms reflecting ETD
Singh et al (2022) 2	Mouth opening (94%), intolerance to foods (86%)	CHL (39%)	39% in OSMF patients	Significant correlation with OSMF grade	PTA, impedance audiometry	Varied curves (A, B, C, As, Ad) by OSMF grade
Sriram et al (2023) 17	Difficulty in speech and swallowing, throat pain, and ear pain	40% of patients had hearing loss; 75% had mild CHL, 25% had moderate CHL	40% (16 out of 40 patients) had hearing loss	Not directly reported	PTA, tympanometry	Not specified
Srivastava et al (2023) 6	Oral mucosa blanching, mouth constriction, burning sensation, difficulty opening mouth, mild deafness due to ETD	CHL; muffled sounds; more common in Grades III & IV	13.3% in Grade II, 53.3% in Grades III & IV	Inferred from hearing loss patterns due to muscle fibrosis	PTA (125-8000 Hz)	Middle ear pathology leading to CHL, primarily in advanced OSMF grades
Rathod et al (2023) 4	Mouth opening restriction, burning sensation, dysphagia, palatal stiffness	CHL; symptoms include difficulty hearing, sensation of ear fullness	39% (in OSMF patients)	Significant correlation with higher OSMF grades; increased ETD with OSMF severity	PTA, tympanometry	Abnormal tympanometric results indicating ETD in OSMF patients
Pottam et al (2023) 18	Symptoms include oral mucosal stiffness, trismus (reduced mouth opening), burning sensation, and changes in the texture of the oral mucosa	CHL; symptoms include reduced hearing sensitivity and possible ear fullness or pressure sensations	39% of patients with OSMF reported hearing impairment, specifically CHL	Significant prevalence of ETD noted, correlating with the severity of OSMF	PTA and tympanometry used to assess hearing sensitivity and middle ear function	Tympanometric analysis indicated abnormal middle ear pressure and compliance, suggesting ETD in OSMF patients
Sreepradha et al (2023) 19	Reduction of mouth opening, mucosal stiffening, referred ear pain	CHL (mild to moderate), ear pain, decreased air conduction threshold	Increased severity of OSMF correlates with hearing loss; Group I had normal hearing; Group IIC had significant hearing impairment	Increased ETD prevalence with severity; 100% normal in Group I, escalating to 40% in Group IIC	Tympanometry and audiometry	Abnormal tympanograms increased with OSMF severity; Type A in mild cases; Types As, B, and C more common in severe cases
Sanwal et al (2023) 20	Burning sensation on hot and spicy food, blanching of buccal mucosa, palpable fibrosis of the oral cavity, difficulty in swallowing, and restricted mouth opening	CHL (normal hearing in 70% of ears, minimal hearing loss in 8.33%, mild hearing loss in 10%, moderate hearing loss in 11.66%). Symptoms of ear pain and hearing impairment noted	30% of patients exhibited some level of hearing loss (combined minimal, mild, and moderate)	Not explicitly stated, but implications suggest ETD due to palatal muscle fibrosis impacting tube function	PTA	Not specified in detail; the study indicates hearing loss correlates with ETD linked to OSMF grades
Anoop et al (2024) 21	Common symptoms of OSMF include: - Mouth opening restriction - Burning sensation - Difficulty in swallowing - Chewing problems - White patches in the oral cavity	CHL was predominant in OSMF patients, characterized by: - Reduced air conduction thresholds - Symptoms include difficulty hearing sounds, especially faint or distant ones	30.8% (37 out of 120 subjects) reported hearing loss, with varying severity based on OSMF stage	24.5% (20 out of 81 OSMF patients) were diagnosed with ETD, highlighting a notable association with OSMF	PTA and bone conduction testing were performed to assess hearing thresholds and identify types of hearing loss	The study found a significant number of patients with flat tympanograms (Type B) indicating middle ear dysfunction, especially in those with advanced stages of OSMF

Abbreviations: CHL, conductive hearing loss; ETD, Eustachian tube dysfunction; OSMF, oral submucous fibrosis; PTA, pure-tone audiometry

Hearing Evaluation Methods

A description of the hearing evaluation techniques applied in each study is given in Table 3. The most widely used diagnostic method was PTA, which evaluated frequencies between 250 and 8000 Hz. According to Devi et al, ³ 39% of patients had mild conductive hearing loss, and there were strong correlations between the severity of OSMF and hearing impairment. Chandran and Aswath ⁵ reported a high prevalence of conductive hearing loss and impaired Eustachian tube function, especially in advanced OSMF stages such as Stage IV, where tympanometric findings indicated sclerotic tympanic membranes. Kumar ¹³ used impedance audiometry to identify poor Eustachian tube function in 53% of ears. Atypical tympanometric findings were also observed in other research, such as Roy et al ¹⁵ and Harkare et al, ¹¹ which linked them to the severity of OSMF and different levels of conductive hearing loss. According to tympanometric data, which showed ETD, 75% of the participants in the study by Desai et al ¹⁶ had mild conductive hearing loss. Recent research by Sreepradha et al ¹⁹ and Anoop et al ²¹ highlighted the significance of assessing middle ear mechanics and found that flat tympanograms, a sign of middle ear dysfunction, were quite common.

Table 3.

Methods of Hearing Evaluation in OSMF Studies.

Author/year	Test type	Frequency range tested (Hz)	Primary hearing deficit detected	Other audiological findings
Devi et al (2015) 3	PTA	250-8000 Hz	Mild conductive hearing loss was the most prevalent, followed by mild sensorineural hearing loss (1%) and moderate sensorineural hearing loss (4%)	56% of ears had normal hearing, while 39% exhibited mild conductive hearing loss. A significant association was found between the grade of OSMF and hearing loss, especially in advanced stages (Groups C and D)
Chandran and Aswath (2016) 5	Audiometry; tympanometry	250-800 Hz	Conductive hearing loss; impaired Eustachian tube function	76.7% of Stage IV patients and 43.3% of Stage III patients showed positive audiograms indicating hearing impairment. Tympanometry showed 63.3% of Stage IV patients with sclerotic tympanic membranes (As curve) 46.7% of Stage III patients showed sclerotic tympanic membranes (As curve), while controls exhibited normal tympanometric findings (A curve)
Sowbhagya et al (2016) 12	PTA, tympanometry	250-8 kHz (air conduction)/250-4 kHz (bone conduction)	Normal hearing (58%); mild conductive hearing loss (35%); moderate conductive hearing loss (6.3%)	55% had Type A tympanogram; ETD indicated by Type C in 8.8% of ears; Type B tympanogram in 11.3% of ears
Kumar (2018) 13	Impedance audiometry	226 Hz	Conductive hearing loss	Significant difference in middle ear pressure - 53% of ears showed no shift in compliance peaks, indicating poor Eustachian tube function - Presence of Type B and C tympanometric curves in many patients indicating middle ear dysfunction
Shah et al (2020) 1	PTA	125-8000 Hz	- Normal hearing (10-15 dB) - Minimal hearing loss (16-25 dB) - Mild hearing loss (26-40 dB) - Moderate hearing loss (41-55 dB)	- 70% of ears were found to have normal hearing - Minimal hearing loss in 8.33% of ears - Mild hearing loss in 10% of ears - Moderate hearing loss in 11.66% of ears - Statistically, no significant difference between OSMF grades and hearing loss categories (P > .05)
Swarup et al (2020) 14	PTA	250, 500, 1000, 2000, 4000	Conductive hearing loss	- Tympanic membrane retraction in 30% of severe cases - No visible ear defects in mild cases (Group M) - Significant association between OSF severity and hearing loss (P = .026)
Roy et al (2020) 15	PTA, tympanometry	250-8000 Hz	Conductive hearing loss	47% of OSMF patients showed positive tympanometric results preoperatively - Bilateral mild conductive hearing loss in Grade III OSMF patients - Type A, B, and C tympanograms indicating varying Eustachian tube function - Significant correlation between OSMF severity and hearing impairment - Postoperative improvements in tympanometric findings
Harkare et al (2021) 11	PTA and tympanometry	250, 500, 1000, 2000, 4000 Hz (common frequencies used in PTA)	Conductive hearing loss (minimal, mild, moderate)	- 69.42% of ears showed normal hearing - Tympanometric findings: normal tympanogram (Type A) in 74.38% of ears, abnormal (Type B: 14.88%, Type C: 10.74%)
Jha KN et al (2021) 10	PTA and tympanometry	250 – 8000 Hz (PTA), not frequency specific for Tympanometry	Conductive hearing loss (36%)	Sensorineural hearing loss (10% due to possible neurotoxicity, Tympanometry showed Type B (14%) and Type C (4%) curves indicating Eustachian tube dysfunction andpossible reduced compliance)
Desai et al (2021) 16	PTA and tympanometry	Frequencies typically tested in PTA include low frequencies (250, 500 Hz) and high frequencies (1000, 2000, 4000, and 8000 Hz) to assess the full range of hearing sensitivity	Conductive hearing loss (CHL) was the primary deficit detected, with 75% of patients experiencing mild CHL and 25% experiencing moderate CHL	Other findings may include tympanometric results indicating middle ear dysfunction, with abnormal tympanograms suggestive of ETD and possible reduced compliance
Singh et al (2022) 2	PTA; impedance audiometry	250-8000	Conductive hearing loss; negative middle ear pressure	ETD noted; varied tympanometric curves by OSMF grade
Sriram et al (2023) 17	PTA	250-8000 Hz	Mild conductive hearing loss (75%) and moderate conductive hearing loss (25%)	60% of patients had normal audiometry findings; specific thresholds were calculated for air conduction across frequencies
Srivastava et al (2023) 6	PTA	125-8000 Hz	Conductive hearing loss	Higher prevalence in Grades III & IV OSMF, with moderate loss in advanced stages; minimal to mild in early stages (Grade II)
Rathod et al (2023) 4	PTA, tympanometry	250, 500, 1000, 2000, 4000, 8000 Hz	Conductive hearing loss (CHL); ETD	Elevated thresholds for lower frequencies; some patients showed mixed hearing loss patterns. Tympanometric findings indicated reduced compliance in middle ear function; abnormal tympanograms (Type B or C) indicating impaired Eustachian tube function and negative middle ear pressure in many OSMF patients
Pottam et al (2023) 18	PTA and tympanometry	Frequencies tested typically include low frequencies (250, 500 Hz) and high frequencies (1000, 2000, 4000, and 8000 Hz) to assess hearing sensitivity across the spectrum.	Conductive hearing loss (CHL) was identified, with significant findings indicating the presence of CHL in a portion of the study population	Findings included tympanometric results that suggest ETD, indicating possible abnormal middle ear pressure or compliance issues
Sreepradha et al (2023) 19	PTA, tympanometry	250-8000 Hz	Conductive hearing loss, particularly in the mid-frequency range (500-2000 Hz); dysfunction in middle ear mechanics	Decreased air conduction thresholds, significant air-bone gaps, and variability in hearing sensitivity between groups; Various tympanometric types observed (A, As, B, C) indicating middle ear function status; Type A in mild cases, As and B in moderate to severe cases
Sanwal et al (2023) 20	PTA	125-8000 Hz	Conductive hearing loss; normal hearing in 70% of ears, minimal hearing loss in 8.33%, mild hearing loss in 10%, moderate hearing loss in 11.66%	Significant difference in hearing loss between early OSMF (Grade I) and severe OSMF (Grade III). Fibrosis of the palatal muscles potentially affects Eustachian tube function
Anoop et al (2024) 21	PTA and tympanometry were the primary tests conducted to evaluate hearing function and middle ear status	Frequencies tested typically ranged from 250 Hz to 8000 Hz for air conduction and bone conduction thresholds	Conductive hearing loss was the primary deficit detected, with significant air-bone gaps noted in the audiometric evaluations	- Flat tympanograms (Type B) were prevalent, indicating possible middle ear dysfunction - Some patients showed air-bone gaps suggestive of conductive components in their hearing loss

Abbreviations: ETD, Eustachian tube dysfunction; OSMF, oral submucous fibrosis; PTA, pure tone audiometry.

Quality Assessment of Cross-Sectional Studies

The NOS is used in Table 4 to assess the methodological quality of cross-sectional research on hearing loss in OSMF patients. A “Good” rating was given to most investigations, indicating sound methodological practices. With a score of 9, Harkare et al ¹¹ received a “Very Good” grade, indicating robust results, comparability, and selection criteria that point to trustworthy conclusions on conductive hearing loss and tympanometric data. Pottam et al ¹⁸ also received a score of 9, highlighting the importance of comprehensive assessments of middle ear function and hearing loss. Sanwal et al ²⁰ showed a substantial correlation between hearing impairment and OSMF severity, with a score of 9. These findings underscore the importance of rigorous study design in understanding the audiological implications of OSMF.

Table 4.

Quality Assessment Tool for Cross-Sectional Studies Using the Newcastle-Ottawa Scale.

S. no	Author (year)	Selection (S1)	S2	S3	S4	Comparability	Outcome 1 (O1)	O2	Total	Quality
1	Devi et al (2015) 3	*	*	*	*	*	*	*	7	Good
2	Sowbhagya et al (2016) 12	*	*	*	*	*	*	*	7	Good
3	Shah et al (2020) 1	*	*	*	**	*	*	*	8	Good
4	Swarup et al (2020) 14	*	*	*	*	*	*	*	7	Good
5	Harkare et al (2021) 11	*	*	*	*	**	**	*	9	Very Good
6	Jha et al (2021) 10	*	*	*	*	**	*	*	8	Good
7	Sriram et al (2023) 17	*	*	*	**	*	*	*	8	Good
8	Rathod et al (2023) 4	*	*	*	*	*	*	*	7	Good
9	Pottam et al (2023) 18	*	*	*	*	**	**	*	9	Very Good
10	Sreepradha et al (2023) 19	*	*	*	*	**	*	*	8	Good
11	Sanwal et al (2023) 20	*	*	*	**	*	**	*	9	Very Good
12	Anoop et al (2024) 21	*	*	*	*	*	*	*	7	Good

*

to be counted as 1.

**

to be counted as 2.

Quality Assessment of Case–Control and Prospective Studies

Table 5 evaluates case–control and prospective studies on hearing loss in OSMF patients. All studies received a “Good” rating, indicating robust methodologies. Notably, Roy et al, ¹⁵ Singh et al, ² and Srivastava et al ⁶ scored 8, reflecting strong selection, comparability, and outcome measures. These studies provide valuable insights into the prevalence and types of hearing loss associated with OSMF. However, studies such as Chandran and Aswath ⁵ , Kumar, ¹³ and Desai et al, ¹⁶ with scores of 7, suggested that there is potential for methodological improvements.

Table 5.

Quality Assessment Tool for Case-Control and Prospective Studies Using the Newcastle-Ottawa Scale.

S. no	Author (year)	Selection (S1)	S2	S3	S4	Comparability	Outcome 1 (O1)	O2	O3	Total	Quality
1	Chandran and Aswath (2016) 5	*	*	*	*	*	*	—	*	7	Good
2	Kumar (2018) 13	*	*	*	*	*	*	*	*	7	Good
3	Roy et al (2020) 15	*	*	*	*	*	*	—	*	8	Good
4	Desai et al (2021) 16	*	*	*	*	*	*	*	*	7	Good
5	Singh et al (2022) 2	*	*	*	*	*	*	*	*	8	Good
6	Srivastava et al (2023) 6	*	*	*	*	*	*	*	*	8	Good

*

to be counted as 1.

Bias Analysis

Figures 2 and 3 illustrate the bias analysis of the included studies. The majority of studies showed proper data collection procedures, and the risk of bias was generally minimal, particularly with regard to confounding (D1) and exposure assessment (D2). Significant differences in participant selection (D3) were noted, though, with certain studies showing higher risks because of non-representative sample selection. The most biased treatments were found to be post-exposure interventions (D4), indicating that hearing results may have been impacted by therapies administered after an OSMF diagnosis. Concerns were also raised by several studies about missing data (D5), which would make the conclusions less compelling overall. Numerous investigations showed a minimal risk of outcome measurement (D6) despite these problems, suggesting accurate evaluations of hearing impairment. Selective reporting (D7) was still a problem in several trials, though. Overall, the body of evidence regarding the audiological effects of OSMF needs to be strengthened by addressing issues with participant selection, missing data, and post-exposure interventions, even though many studies corrected for exposure measurement and confounding variables. Future research should think about performing a subgroup analysis depending on OSMF severity (mild, moderate, or severe) to determine whether hearing impairment is more noticeable in advanced instances, given the variation in results among studies. Factors including age, length of OSMF, and chewing tobacco use should also be considered in subgroup analysis. Furthermore, utilizing I2 statistics to address statistical heterogeneity and considering the possible influence of various diagnostic techniques may offer important insights into the causes of the findings’ variability.

Figure 2.

Individual risk of bias assessment using ROBINS – E Tool.

Figure 3.

Overall risk of bias assessment using ROBINS – E Tool.

Discussion

OSMF is becoming more well acknowledged as a complicated disorder that presents serious health risks, especially in areas where areca nut intake is common. Even though earlier research has linked OSMF to several issues, such as dysphagia and oral cancer, the precise connection between OSMF and hearing loss is still unknown. There is a significant lacuna in the literature about the pathophysiological processes and magnitude of the association between OSMF and auditory impairment, even in the face of accumulating evidence that suggests this association may exist. By combining the results of several research that investigated hearing loss in patients with OSMF, this systematic review seeks to address these gaps in literature. It is critical to comprehend this relationship because hearing loss can significantly damage a patient’s quality of life and make managing OSMF more difficult. Two reasons justify concentrating on this topic: first, it highlights the potential audiological effects of an already challenging condition; second, it encourages the application of interdisciplinary approaches in OSMF treatment. Healthcare professionals can improve early detection and intervention, which will eventually improve patient outcomes, by including audiological tests into the routine care of patients with OSMF.

The inflammatory processes linked to OSMF may give rise to ETD, a mechanism for hearing impairment in patients with OSMF. Prolonged inflammation can cause fibrosis, which impairs the anatomy of the middle ear and the Eustachian tube’s ability to function. There is a correlation between the high prevalence of conductive hearing loss observed in advanced OSMF and the alteration of middle ear mechanics caused by inflammation. Siddiqui et al discovered this strong correlation between ETD and hearing loss, pointing out that fibrosis and inflammation can block the Eustachian tube, affecting pressure equalization that is essential for proper auditory function. ⁸ Similarly, a tympanometric investigation by Chandran and Aswath revealed that individuals with OSMF had impaired Eustachian tube function because of fibrotic alterations in the oral cavity. ⁵ The meta-analysis by Rathod et al highlighted the patients’ increased risk of developing ETD by indicating that the affected auditory structures may be impacted by fibrotic alterations that go beyond the mouth mucosa. ²² The correlation between auditory abnormalities and the clinical and histological severity of OSMF was confirmed by Singh et al, ² demonstrating that fibrosis has a substantial effect on middle ear function and hearing. ² The complex link between OSMF, ETD, and hearing impairment is shown by these data taken together, highlighting the significance of assessing auditory function in OSMF patients for efficient therapeutic management.

Considerable information on the hearing capacities of patients with OSMF has been gleaned from studies employing audiological diagnostic techniques. PTA is the method of assessment that is used the most frequently among these approaches. However, to gain a more comprehensive understanding of auditory function in OSMF patients, it is essential to include additional methods such as tympanometry and acoustic reflex tests. In addition to evaluating middle ear function, tympanometry can be used to diagnose disorders including ETD, which is frequently linked to OSMF. ⁸ Acoustic reflex testing further evaluates the auditory pathway and can indicate the status of the stapedius muscle in response to loud sounds, providing additional useful information about the integrity of the auditory system. ⁵

It is noteworthy that combining these complimentary assessments improves the evaluation of the connection between auditory abnormalities and OSMF severity. Healthcare providers can more precisely determine the degree of hearing impairment which is often underdiagnosed and undertreated in this population by using a comprehensive approach to audiological assessment. ⁴ These comprehensive evaluations are crucial for tailoring effective intervention strategies and ensuring that patients receive the appropriate therapy for their auditory needs.

The relationship between the degree of hearing loss and the duration as well as the severity of OSMF is a significant finding that needs more research. Research has shown a substantial correlation between the duration of OSMF and the degree of hearing loss, suggesting that patients with a longer history of the disorder typically have more severe auditory impairments.^6,23 The discovery emphasizes the vital necessity of prompt diagnosis and treatment of OSMF to reduce the likelihood of hearing impairment. Regular audiological monitoring is crucial since OSMF being a chronic condition is frequently characterized by a progressive deterioration of symptoms. Early detection of hearing problems can be facilitated by such surveillance, enabling prompt interventions. ²⁴

Moreover, as OSMF progresses, the associated degree of hearing impairment tends to escalate, reinforcing the necessity for proactive management strategies. ²⁴ Additionally, preoperative evaluations often reveal significant hearing loss in OSMF patients, which can be exacerbated without appropriate treatment. ²⁵ Overall, the interplay between OSMF duration, severity, and hearing loss calls for heightened awareness and regular auditory assessments to ensure optimal patient outcomes.

Recent research has focused a great deal of emphasis on the function of areca nut in the pathophysiology of OSMF and its possible connection to hearing impairment. Consuming areca nuts is linked to several systemic side effects, such as potential ototoxicity, which could impair auditory function. Long-term areca nut usage may cause systemic alterations that affect hearing function, possibly through inflammatory pathways, according to research by Gupta et al. ²⁶ This research highlights the critical need for public health initiatives targeted at lowering its usage and raises serious concerns about the wider effects of lifestyle decisions, such as the use of areca nuts, on the health of the hearing in OSMF patients.

Hearing impairment may also be indirectly caused by psychosocial issues associated with living with OSMF, in addition to ETD. Psychological discomfort is common in patients with chronic diseases, and it can increase awareness of sensory abnormalities, including hearing loss. According to research by Chaudhary, ²⁷ psychological assistance may be essential for improving overall health outcomes, including auditory function, as it underlines the psychosocial burden experienced by OSMF patients. Both the physical and psychological components of OSMF have a substantial impact on the overall quality of life (QoL) of those who have the condition. OSMF causes pain, trouble swallowing, and limited mouth opening, all of which can make it harder to go about everyday tasks. In addition to these physical limits, patients may also face social and emotional difficulties, such as low self-esteem, diminished social relationships, and shame. Furthermore, because OSMF is chronic, there is frequently ongoing concern about the possibility of getting oral cancer. The QoL of OSMF patients must be handled holistically, combining medical and psychosocial support to enhance general well-being.^9,28

It is critical to address mental health in addition to physical health because doing so could greatly improve the QoL of patients affected by OSMF. For this reason, comprehensive care plans that combine psychological and medicinal therapies are necessary to maintain auditory function and optimize health outcomes in this population. The audiological profile of patients with OSMF may be complicated by the coexistence of systemic and oral diseases. Studies show that people with OSMF are more likely to have comorbid conditions such as diabetes and hypertension, which have both been linked to hearing loss.^2,38,29 Thus, to properly manage these comorbidities and comprehend their combined impact on hearing function, a multidisciplinary strategy involving dentists, audiologists, and general healthcare practitioners is necessary.

There are still numerous shortcomings in the research that have been done on OSMF and hearing impairment, despite the expanding volume of literature. Small sample sizes are a common characteristic of research, which limits how broadly the results may be applied. Direct comparisons between studies are further complicated by differences in patient demographics, audiological evaluation techniques, and study designs. Future research should prioritize larger, multicenter trials employing standardized assessment protocols to yield more robust data regarding the prevalence and mechanisms of hearing loss in OSMF patients.^23,30,31 It will be essential to close these gaps to create complete management plans that improve patient outcomes. In the end, better therapy, and a higher standard of living for those impacted by OSMF will result from a full grasp of the interactions between the disorder, its comorbidities, and hearing loss.

Strengths and Limitations

The literature on OSMF and hearing impairment is thoroughly synthesized in this systematic review, which also highlights important relationships and important processes. This review’s strength is its thorough methodology, methodical approach, and inclusion of a variety of articles, all of which improve the validity of the findings. However, several restrictions need to be solved. The findings’ generalizability may be impacted by the small sample numbers, inconsistent diagnostic tool use, and possible publication bias of many of the included studies. The results could have been affected by confounding factors like alcohol use, smoking, and nutritional deficits, whose effects were not always taken into consideration. To give more trustworthy evidence about the effect of OSMF on hearing health, future research should concentrate on bigger, multicenter trials using established procedures and take longitudinal outcomes into account.

Conclusion

This review highlights a significant association between OSMF and hearing impairment, including both conductive and sensorineural hearing loss. The hearing issues are likely due to fibrotic changes affecting the middle ear and Eustachian tube. Despite some methodological challenges, such as participant selection bias, inconsistent therapies, and missing data, the studies consistently link OSMF with hearing loss, indicating that the fibrosis involved may impact not only the oral cavity but also auditory structures, affecting hearing.

Future research should focus on several key areas. Longitudinal studies are essential to determine whether early intervention, including medical or surgical treatments, can reduce hearing loss over time and establish a clearer causal relationship between OSMF and hearing impairment. Additionally, while conductive hearing loss has been well-studied, more research is needed on sensorineural hearing loss in OSMF patients, particularly to explore potential systemic effects or damage to the inner ear and auditory nerve. Larger, multicenter trials with consistent audiological evaluations and standardized diagnostic criteria are crucial for reducing biases and improving the quality of the evidence. These efforts will help develop better clinical care plans for OSMF patients.

Key Findings

• A significant association between the severity of OSMF and conductive hearing loss.

• ETD as a likely mechanism for hearing loss in OSMF.

• Sensorineural hearing loss observed in some OSMF patients, possibly due to systemic effects or comorbidities.

Based on these findings, routine audiological screening, particularly for severe OSMF patients or those with a history of areca nut use, is recommended. Early detection can improve outcomes by enabling timely interventions.