Reviewing the epidemiological literature on the prevalence of temporomandibular dysfunction (TMD) in India is the goal of this systematic review. Using pre-established inclusion and exclusion criteria, a literature search was carried out for pertinent studies from a number of databases, including the National Library of Medicine's PubMed, SCOPUS, and Web of Science. The quality of a few chosen papers that fit the search criteria was assessed using the JBI tool, and the results were then compiled into tables. Data about the study population, the diagnostic technique utilized, the prevalence of TMD, and other pertinent findings were retrieved from a total of 25 studies. The prevalence of TMD was 35% overall, with the majority of the studies conducted on young students in India. The data showed a high degree of heterogeneity, indicating that TMD predominantly impacts women and is a serious and expanding illness in the population at large. The information that is now accessible highlights the necessity of conducting more study on the etiologic variables linked to TMD in order to put effective preventative measures into place.
Introduction
Temporomandibular disorders (TMDs) are a broad category of conditions affecting the masticatory muscles, temporomandibular joints (TMJ), and associated tissues. These disorders are characterized by symptoms like joint pain, muscle tenderness, restricted jaw movement, and audible joint sounds (clicking or crepitation). TMDs significantly impact physical and mental health, leading to diminished quality of life and, in severe cases, long-term disability.
The causes of TMDs are multifaceted and classified into predisposing, initiating, and perpetuating factors. Biomechanical factors are issues such as malocclusion, parafunctional habits (e.g., bruxism and clenching), and postural imbalances that contribute to TMJ dysfunction. Psychosocial elements, including stress, anxiety, depression, and psychological disorders, exacerbate TMD symptoms, often leading to chronic pain syndromes. Systemic factors involve osteoarthritis, rheumatoid arthritis, and autoimmune disorders [1]. Genetic variations, such as those in COMT and ADRB2 genes, influence pain sensitivity and predispose individuals to chronic conditions [2]. Hormonal influences are seen particularly in women, which are linked due to TMD's greater incidence in women, emphasizing the role of estrogen and other hormones in joint health.
TMDs frequently coexist with other musculoskeletal and systemic conditions, including arthritis, migraines, fibromyalgia, chronic back pain, and irritable bowel syndrome. Symptoms like headaches, restricted jaw movement, and muscle discomfort are frequently reported and can significantly affect daily activities and overall well-being.
Epidemiological studies indicate wide variations in TMD prevalence, with estimates ranging from 5% to 60% globally [3]. Young adults and women of reproductive age represent high-risk groups due to hormonal, psychological, and lifestyle factors. Academic pressures, financial difficulties, and stress-inducing habits contribute to TMD prevalence among students, a particularly vulnerable demographic.
Clinical exams, Fonseca/self-developed questionnaires, and case history records are the primary diagnostic methods for TMDs. The 1992 introduction of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) offered a systematic method for classifying TMD into two parts: psychological (Axis II) and physical (Axis I). In 2014, the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) were introduced, providing improved diagnostic precision for research and clinical applications.
The contribution of dental factors to TMD remains a subject of debate. Malocclusion, occlusal interference, tooth loss, and ill-fitting prostheses are suspected risk factors. However, inconsistent evidence highlights the need for further research. Parafunctional habits like clenching and grinding, along with certain dental procedures [4-9], can exacerbate symptoms and warrant careful evaluation during treatment planning [10-15].
Evidence synthesis of literature available regarding TMD epidemiology in other countries has been published [2]. However, there have been very few available for India. Therefore, this systematic review was planned and carried out in order to respond to the study inquiry: What is the prevalence of TMDs in India?
Search strategy
An electronic search was conducted in PubMed, SCOPUS, Web of Science, and Google Scholar to locate relevant papers published up until December 31, 2024; the investigation was restricted to literature written in English. The search strategy in all databases was designed using controlled vocabulary (MeSH terms in PubMed) and free-text phrases in the titles and/or abstracts. The search strategies were accomplished using keywords based on each portion of the PO question, which were separated utilizing the Boolean operator OR and then combined employing the Boolean operator AND. The reference lists of the retrieved studies will also be searched. Table 1 summarizes the search strategy developed.
Table 1. Search Strategy
|
Sr. No |
Search Strategy |
|
1 |
Temporomandibular Disfunction syndrome OR Temporomandibular disorder OR TMD |
|
2 |
Indian Population OR Prevalence OR Incidence |
|
9 |
1 AND 2 |
|
|
|
Figure 1. PRISMA flowchart |
Table 2. Data extraction
|
Sno |
Author/ year |
Type of study |
Region |
Tool used |
Study population |
Prevalence |
Findings |
|
1 |
Rajesh Shetty et al. 2010 [16] |
Cross sectional |
Mangalore |
Constructed questionnaire, Clinical examination |
healthy, asymptomatic edentulous patients not wearing complete dentures |
59% |
Over half of the asymptomatic patients experienced TMD symptoms, but they had no idea of them; 59% of the subjects had at least one TMD symptom. TMDs were more common in women (62.5%) than in men (56.6%). |
|
2 |
Amita Aditya et al. 2012 [17] |
Cross-Sectional study5 |
Pune |
Case history and constructed questionnaire, Clinical examination |
Adults who are institutionalized or receiving outpatient care due to a psychosocial illness diagnosis |
subjective TMD symptoms to be 12%, objective TMD symptoms present in 19.5% of participants |
Patients with psychosocial issues do not seem to have an abnormally high frequency of TMJ dysfunction symptoms. Despite the fact that there is considerable comorbidity between these two illnesses, no obvious connection could be found. |
|
3 |
Priyanka Modi et al. 2012 [18] |
Cross sectional |
Loni |
Fonseca questionnaire |
Medical and dental students |
45.16% |
This student group had a significant frequency of TMD; nevertheless, the majority of illnesses were moderate. There was no analytically substantial correlation between TMD intensity and sexuality. |
|
4 |
Saraswati K. Gopal et al. 2014 [19] |
Cross sectional |
Chennai |
Case history and constructed questionnaire, Clinical examination |
Patients in Private dental college |
60% |
Since there was no discomfort, several of the asymptomatic individuals were unaware of the underlying issue with their TMJ. |
|
5 |
Kaberi Majumder et al. 2015 [20] |
Cross sectional study |
Gurgaon |
Helkimo anamnestic index (Ai) and clinical dysfunction index (Di) |
Student in 5 different colleges |
64.4%
|
TMD was highly prevalent among students and was strongly linked to anxiety and sadness. |
|
6 |
Asawa et al. 2015 [21] |
Cross-Sectional study |
Dungarpur District |
clinical examination according to WHO proforma |
General population |
21.4% |
Men were more impacted than women, and TMJ signs and symptoms were more common in the 45–54 age range. TMJ symptoms were substantially correlated with skeletal fluorosis (33.0%). |
|
7 |
Jivnani et al. 2017 [22] |
Cross sectional |
Lucknow |
DC/TMD, hospital anxiety and depression scale (HADS), T-Scan |
Student in Private dental college |
17% |
TMD was significantly correlated with both functional occlusal measures and psychological factors. |
|
8 |
Ahuja et al. 2018 [23] |
cross sectional study |
Gaziabad |
Clinical evaluation and questionnaire along with perceived stress scale (PSS). |
Students in Private dental college |
30.6%
|
One important etiologic factor that contributes to the development and maintenance of TMDs in dentistry students is stress. The age range of 21 to 25 years old was shown to have the highest prevalence of TMDs, with MPDS predominating. Females had the highest incidence of disc displacement (66.0%) and were shown to have a greater prevalence of TMDs than males. |
|
9 |
Reshmi et al. 2018 [24] |
Cross sectional |
Kozhikode |
Helkimo index Clinical examination |
Partially edentulous patients in OPD of dental college |
57.4% |
TMD was more common in women than in men, and it was more common in individuals with Kennedy's class I mandibular condition and a combination of maxillary class I and mandibular class II situations. Although TMD symptoms decreased with age, the difference was not statistically significant. |
|
10 |
Banerjee et al. 2019 [25] |
Cross sectional |
Lucknow |
Self-reported questionnaire |
Dental students in private dental college |
30% |
The most often reported symptoms among the students were TMJ sound, headache, and earache. |
|
11 |
Dr. Preeti Nair et al. 2018 [26] |
Cross sectional |
Bhopal |
Case history and constructed questionnaire , Clinical examination |
Patients visiting Private dental college |
55.3%
|
The results of this study indicated that younger people, particularly women, were at a higher risk of getting TMDs. Overstretching when yawning (31%), parafunctional behaviors (34%), jaw trauma (23%), dental treatment (8%), and traumatic dental treatment (4%) were factors that contributed to TMD. |
|
12 |
Sandhya Jain et al. 2018 [27] |
Cross sectional |
Indore |
Fonseca’s Questionnaire |
Patients under orthodontic treatment in dental college |
25.3% |
In the age group of 19 to 30, a considerably higher proportion of girls than men presented with TMDs. Age-related increases in TMD prevalence are also seen. |
|
13 |
Pradeepta Kaushal et al. 2018 [28] |
Cross sectional study |
Indore |
Case history and constructed questionnaire, Clinical examination Helkimo Index |
Student in Private dental college |
18.6% |
Stress showed a highly significant value and was the primary cause for TMD. The most common sound found was clicking, and the affected muscle was the lateral pterygoid (27%), showing prevalence in females. |
|
14 |
Pooja Bhave et al. 2019 [29] |
Cross sectional |
Navi-Mumbai |
RDC/TMD |
Student in Private dental college |
51%
|
It is possible that symptoms do not always accompany the indicators of TMDs. Prior to signs appearing, patients can remain asymptomatic for an extended length of time. |
|
15 |
Thomas et al. 2020 [30] |
Cross sectional |
Central kerala |
Case history and constructed questionnaire, Clinical examination |
Students from professional colleges |
48% |
The current investigation in professional institutions found that TMD was more common in men. |
|
16 |
Varsha Ushakar et al. 2020 [31] |
cross sectional study |
Ernakulam |
Fonseca questionnaire |
Students in Private dental college |
59.3% |
Age has been shown to have a substantial impact on the severity of TMD, but the individual's sex had no discernible effect. |
|
17 |
Swapna Bettanapalya Venkatesh et al. 2021 [32] |
Cross sectional |
Manipal |
RDC/TMD Perceived Stress Scale (PSS) questionnaire |
Student in Private dental college |
30.7% |
Substantial correlation between stress, TMDs, and salivary cortisol levels. |
|
18 |
Kumari Sonam Jha et al. 2021 [33] |
Cross sectional study |
Jharkhand |
Case history and constructed questionnaire, Clinical examination |
Patient in Private dental college |
1.25% |
According to the factors that were examined, clicking was the most prevalent symptom. Incidence of TMD decreases as the age of an individual advances. More common in females compared to males, |
|
19 |
Ajay Kumar et al. 2021 [34] |
cross sectional study |
Mangalore |
RDC/TMD criteria. |
Professional swimmers |
13.54 % |
Competitive swimmers are prone to TMDs. TMD was linked to more than an hour of practice per day and more than five days of practice. TMD was more common among swimmers who used the backstroke. |
|
20 |
Munazza et al. 2020 [35] |
Comparative Study |
Mangalore |
Fonseca’s Anamnestic index and Zung’s Self-rating Anxiety Scale. |
Students in Private dental college |
46% |
Preclinical students had a larger percentage of stress, whereas clinical students had a higher percentage of TMD. The degree of stress was significantly correlated with TMD. Compared to male students, the prevalence and severity of TMD were greater among female students. |
|
21 |
Sanjana Devi et al. 2021 [36] |
Retrospective study |
Chennai |
Previous data, case history |
Patients in Private dental college |
0.8% |
Disc displacement was more prevalent and TMD was more prevalent in men. And the age range of 30 to 39 was the most impacted. |
|
22 |
Jayant Prakash et al. 2022 [37] |
cross-sectional study |
Muzaffarpur |
Case history and constructed questionnaire, Clinical examination |
Patients in Private dental college |
35.7% of the elderly population |
More females were affected compared to males. Subjects who reported bruxism had a significantly higher prevalence of TMD symptoms. |
|
23 |
Jaishankar et al. 2023 [38] |
Cross sectional |
India |
online questionnaire |
Musicians and vocalist |
50.8% |
Playing an instrument raises the likelihood of acquiring TMD, and playing the wind instrument puts one at greater risk. |
|
24 |
Ramachandran et al. [39] 2023 |
Cross-sectional Study. |
Pondicherry |
Case history records |
Patients in Private dental college |
1% |
Women were more likely than males to report having TMJ discomfort. Joint noises and discomfort were the most often reported symptoms. |
|
25 |
Chinthalapalli et al. 2024 [40] |
Cross-sectional Study |
Davangere |
DC-TMD |
Dental students |
61.2 %. |
TMDs are more likely to occur among dental students, especially those participating in clinical programs, and are closely associated with increased stress levels. |
Table 3. Data Extraction
|
Cochran's Q |
df |
P |
I² |
Tau Squared (T²) |
|
220.129 |
24 |
0 |
89.097% |
0.041 |
Table 4. Statistical Analysis using random effects model
|
Prevalence |
Raw Prevalence |
SE of transformed Prevalence |
Variance |
Weight |
Normal Approximation interval |
|
|
Lower Bound |
Upper Bound |
|||||
|
0.35923 |
0.35923 |
0.01422 |
0.0002 |
4946.89545 |
0.33136 |
0.38709 |
|
|
|
Figure 2. Forest Plot |
Publication bias was assessed using LFK index the value was 13.699 indicating high publication bias.
|
|
|
Figure 3. Doi Plot for publication bias |
Table 5. Quality assessment of the studies included in the systematic review
|
SN |
Study |
Were the requirements to be included in the sample well-defined? |
Were the research participants and environment thoroughly explained? |
Were the measurements of exposure accurate and legitimate? |
Were the conditions measured using unbiased, accepted standards? |
Have complicating variables been discovered? |
Were methods for handling complicating variables mentioned? |
Were the measurements of the results accurate and legitimate? |
Was suitable analytical assessment applied? |
Score |
Quality |
|
1 |
Shetty R et al. 2010 |
Y |
N |
Y |
Y |
N |
N |
N |
Y |
0.5 |
Moderate |
|
2 |
Aditya A et al. 2012 |
Y |
N |
Y |
Y |
N |
N |
Y |
Y |
0.6 |
Moderate |
|
3 |
Modi P et al. 2012 |
Y |
N |
N |
N |
N |
N |
N |
Y |
0.3 |
Low |
|
4 |
Gopal SK et al. 2014 |
Y |
N |
Y |
Y |
N |
N |
Y |
Y |
0.6 |
Moderate |
|
5 |
Majumder K et al. 2015 |
Y |
Y |
Y |
Y |
N |
N |
Y |
Y |
0.8 |
High |
|
6 |
Asawa K et al. 2015 |
Y |
Y |
Y |
Y |
N |
N |
Y |
Y |
0.8 |
High |
|
7 |
Jivnani HM et al. 2017 |
N |
N |
Y |
Y |
N |
N |
N |
Y |
0.4 |
Moderate |
|
8 |
Ahuja V et al. 2018 |
N |
N |
Y |
Y |
N |
N |
Y |
Y |
0.5 |
Moderate |
|
9 |
Reshmi M et al. 2018 |
Y |
N |
Y |
Y |
N |
N |
Y |
Y |
0.6 |
Moderate |
|
10 |
Banerjee A et al. 2019 |
N |
N |
N |
N |
N |
N |
N |
Y |
0.1 |
Low |
|
11 |
Nair P et al. 2018 |
N |
N |
Y |
Y |
N |
N |
Y |
Y |
0.5 |
Moderate |
|
12 |
Jain S et al. 2018 |
Y |
N |
N |
N |
N |
N |
Y |
Y |
0.4 |
Moderate |
|
13 |
Kaushal P et al. 2018 |
Y |
N |
Y |
Y |
N |
N |
Y |
Y |
0.6 |
Moderate |
|
14 |
Bhave P et al. 2019 |
Y |
N |
Y |
Y |
N |
N |
Y |
Y |
0.6 |
Moderate |
|
15 |
Thomas AS et al. 2020 |
N |
N |
N |
N |
N |
N |
N |
Y |
0.1 |
Low |
|
16 |
Ushakar V et al. 2020 |
N |
N |
N |
N |
N |
N |
N |
Y |
0.1 |
Low |
|
17 |
Venkatesh SB et al. 2021 |
Y |
N |
Y |
Y |
N |
N |
Y |
Y |
0.6 |
Moderate |
|
18 |
Jha KS et al. 2021 |
Y |
N |
Y |
Y |
N |
N |
Y |
Y |
0.6 |
Moderate |
|
19 |
Kumar A et al. 2021 |
Y |
Y |
Y |
Y |
N |
N |
Y |
Y |
0.8 |
High |
|
20 |
Munazza S et al. 2024 |
Y |
Y |
N |
N |
N |
N |
N |
Y |
0.4 |
Moderate |
|
21 |
Devi S et al. 2021 |
Y |
Y |
UC |
UC |
Y |
N |
UC |
Y |
0.5 |
Moderate |
|
22 |
Prakash J et al. 2022 |
Y |
Y |
Y |
Y |
N |
N |
Y |
Y |
0.8 |
High |
|
23 |
Jaishankar HP et al. 2023 |
Y |
Y |
N |
N |
N |
N |
N |
Y |
0.4 |
Moderate |
|
24 |
Ramachandran S 2023 |
Y |
Y |
N |
N |
N |
N |
Y |
Y |
0.5 |
Moderate |
|
25 |
Chinthalapalli SJ et al. 2024 |
Y |
Y |
Y |
Y |
N |
N |
Y |
Y |
0.7 |
High |
Y: Yes, N: No; UC: Unclear
The Joanna Briggs Institute (JBI) analytical cross-sectional study methodology was employed to assess the quality of the contained research. Scores of 1 for "Yes" and "Not useful," 0 for "No," and "Unclear" were given to each research after it was examined separately. The cumulative score assigned to each question was divided by the maximum achievable score, i.e. eight. If the scores were in the range of 0 to 0.3, the studies were considered as low quality; scores between 0.4 to 0.6 as moderate quality, whereas studies with scores between 0.7 to 1.0 were considered as high quality. This review comprised five high-quality studies, sixteen moderate-quality studies, and four low-quality studies.
Results and Discussion
The total prevalence of TMDs was 35%. The majority of studies on dentistry students were conducted in colleges and hospitals. The majority of the studies were cross-sectional. These investigations were mostly conducted in south India, then central India, and finally north India. There was no research reported from India's northeast area [41-44]. The majority of TMD cases were recorded using a self-developed questionnaire, case history, and clinical examination, although the questionnaire's validity was lacking due to its unstructured nature. Six writers assessed TMD using the Fonseca questionnaire, whereas five authors utilized the DC/TMD criteria. When all studies' data were examined, they revealed a similar female predisposition, with the clicking sound being the most prevalent TMD symptom. Disc derangement with/without decrease was the least prevalent. Almost all studies looked at overall TMD prevalence rather than specific types of TMD.
Conclusion
The pooled prevalence of temporomandibular disorders (TMDs) among dental students is 35%. The absence of standardized diagnostic tools in most studies restricted the reliability of their findings. Geographically inclusive studies are needed, as research has mostly focused on southern regions and there is a lack of data from northeastern India. A consistent female preference and joint clicking as the predominant symptom were noted. Future studies ought to focus on standardized diagnostic criteria and explore the specific subtypes of TMDs to enhance understanding of their distribution and contributing factors.
Future directions
Despite growing awareness of TMD as a significant health concern, challenges such as inconsistent diagnostic criteria and research variability persist. A deeper understanding of the interplay between genetic, systemic, and mechanical factors is essential for developing effective preventive and therapeutic strategies. To assure impartial findings in our nation, more research with high-quality designs, such as case-control and long-term cohort studies, utilizing standardized diagnostic methodologies and tools, such as DC TMD criteria, should be conducted with large sample sizes. The findings of such big, well-conducted, population-based research will help to address certain etiological variables more effectively.
Acknowledgments: None
Conflict of interest: None
Financial support: None
Ethics statement: None