Journal of Clinical Medicine

Research

14 pages, 596 KiB

Open AccessArticle

The Impact of Parafunctional Habits on Temporomandibular Disorders in Medical Students

by Michał Zemowski, Yana Yushchenko and Aneta Wieczorek

J. Clin. Med. 2025, 14(15), 5301; https://doi.org/10.3390/jcm14155301 - 27 Jul 2025

Background: Temporomandibular disorders (TMD) are common musculoskeletal conditions affecting the temporomandibular joints, masticatory muscles, and associated structures. Their etiology is complex and multifactorial, involving anatomical, behavioral, and psychosocial contributors. Parafunctional habits such as clenching, grinding, and abnormal jaw positioning have been proposed as [...] Read more.

Background: Temporomandibular disorders (TMD) are common musculoskeletal conditions affecting the temporomandibular joints, masticatory muscles, and associated structures. Their etiology is complex and multifactorial, involving anatomical, behavioral, and psychosocial contributors. Parafunctional habits such as clenching, grinding, and abnormal jaw positioning have been proposed as contributing factors, yet their individual and cumulative contributions remain unclear. This exploratory cross-sectional study aimed to evaluate the prevalence and severity of parafunctional habits and their association with TMD in medical students—a group exposed to elevated stress levels. Subjects were examined in Krakow, Poland, using the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) protocol. Methods: Participants completed a 21-item Oral Behavior Checklist (OBC) assessing the frequency of oral behaviors on a 0–4 scale. A self-reported total parafunction load was calculated by summing individual item scores (range: 0–84). Logistic regression was used to evaluate associations between individual and total parafunction severity scores and TMD presence. Results: The study included 66 individuals aged 19–30. TMD was diagnosed in 55 participants (83.3%). The most commonly reported habits were resting the chin on the hand (90.9%) and sleeping in a jaw-compressing position (86.4%). Notably, jaw tension (OR = 14.5; p = 0.002) and daytime clenching (OR = 4.7; p = 0.027) showed significant associations with TMD in the tested population. Each additional point in the total parafunction score increased TMD odds by 13.6% (p = 0.004). Conclusions: These findings suggest that parafunctional behaviors—especially those involving chronic muscle tension or abnormal mandibular positioning—may meaningfully contribute to the risk of TMD in high-stress student populations. Moreover, the cumulative burden of multiple low-intensity habits was also significantly associated with increased TMD risk. Early screening for these behaviors may support prevention strategies, particularly among young adults exposed to elevated levels of stress. Full article

(This article belongs to the Special Issue Bruxism and Temporomandibular Disorders: Current Advances and Future Challenges)

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13 pages, 271 KiB

Open AccessArticle

Association Between Gum Chewing and Temporomandibular Disorders

by Yana Yushchenko, Michał Zemowski, Daniil Yefimchuk and Aneta Wieczorek

J. Clin. Med. 2025, 14(15), 5253; https://doi.org/10.3390/jcm14155253 - 24 Jul 2025

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Abstract

Background: Gum chewing is a common habit among young adults, often promoted for its oral health and psychological benefits. However, as a repetitive and non-functional activity, it is also considered a potential risk factor for temporomandibular disorder (TMD), particularly when practiced chronically. [...] Read more.

Background: Gum chewing is a common habit among young adults, often promoted for its oral health and psychological benefits. However, as a repetitive and non-functional activity, it is also considered a potential risk factor for temporomandibular disorder (TMD), particularly when practiced chronically. The aim of this study was to evaluate whether excessive gum chewing is associated with a higher prevalence of TMD among young adults presumed to be under elevated academic stress based on their demographic characteristics. Methods: Participants were examined in Krakow, Poland, using the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) protocol. Participants completed a structured questionnaire assessing gum-chewing frequency, duration, and chronicity. Associations between chewing behaviors and TMD presence were analyzed using univariate logistic regression (α = 0.05). Results: This study included young adults 66 participants aged 19–30. TMD was diagnosed in 55 participants (83.3%), including muscular disorders (n = 9; 16.4%), articular disorders (n = 10; 18.2%), and combined muscular–articular disorders (n = 38; 57.6%). More than 70% of participants reported chewing gum for over five years. No statistically significant associations were found between TMD occurrence and the frequency, duration, or chronicity of gum chewing (p > 0.05). Conclusions: These findings suggest that, in the absence of other contributing factors, gum chewing may not independently contribute to TMD development. The elevated TMD prevalence may reflect confounding variables such as high academic stress, narrow age distribution, or female predominance. However, the limited sample size limits statistical power, particularly for detecting subtle effects potentially distorted by other variables. Additionally, the cross-sectional nature of this study precludes causal interpretation. Further studies in larger and more heterogeneous populations are recommended. Full article

(This article belongs to the Special Issue Bruxism and Temporomandibular Disorders: Current Advances and Future Challenges)

17 pages, 1208 KiB

Open AccessArticle

Structural Features of the Temporomandibular Joint Evaluated by MRI and Their Association with Oral Function and Craniofacial Morphology in Female Patients with Malocclusion: A Cross-Sectional Study

by Mari Kaneda, Yudai Shimpo, Kana Yoshida, Rintaro Kubo, Fumitaka Kobayashi, Akira Mishima, Chinami Igarashi and Hiroshi Tomonari

J. Clin. Med. 2025, 14(14), 4921; https://doi.org/10.3390/jcm14144921 - 11 Jul 2025

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Abstract

Background/Objectives: Temporomandibular disorders (TMDs) are a group of musculoskeletal and neuromuscular conditions involving the temporomandibular joint (TMJ), masticatory muscles, and related anatomical structures. Although magnetic resonance imaging (MRI) is considered a noninvasive and highly informative imaging modality for assessing TMJ soft tissues, [...] Read more.

Background/Objectives: Temporomandibular disorders (TMDs) are a group of musculoskeletal and neuromuscular conditions involving the temporomandibular joint (TMJ), masticatory muscles, and related anatomical structures. Although magnetic resonance imaging (MRI) is considered a noninvasive and highly informative imaging modality for assessing TMJ soft tissues, few studies have examined how TMJ structural features observed on MRI findings relate to oral function and craniofacial morphology in female patients with malocclusion. To investigate the associations among TMJ structural features, oral function, and craniofacial morphology in female patients with malocclusion, using MRI findings interpreted in conjunction with a preliminary assessment based on selected components of the DC/TMDs Axis I protocol. Methods: A total of 120 female patients (mean age: 27.3 ± 10.9 years) underwent clinical examination based on DC/TMDs Axis I and MRI-based structural characterization of the TMJ. Based on the structural features identified by MRI, patients were classified into four groups for comparison: osteoarthritis (OA), bilateral disk displacement (BDD), unilateral disk displacement (UDD), and a group with Osseous Change/Disk Displacement negative (OC/DD (−)). Occlusal contact area, occlusal force, masticatory efficiency, tongue pressure, and lip pressure were measured. Lateral cephalometric analysis assessed skeletal and dental patterns. Results: OA group exhibited significantly reduced occlusal contact area (p < 0.0083, η² = 0.12) and occlusal force (p < 0.0083, η² = 0.14) compared to the OC/DD (−) group. Cephalometric analysis revealed that both OA and BDD groups had significantly larger ANB angles (OA: 5.7°, BDD: 5.2°, OC/DD (−): 3.7°; p < 0.0083, η² = 0.21) and FMA angles (OA: 32.4°, BDD: 31.8°, OC/DD (−): 29.0°; p < 0.0083, η² = 0.17) compared to the OC/DD (−) group. No significant differences were observed in masticatory efficiency, tongue pressure, or lip pressure. Conclusions: TMJ structural abnormalities detected via MRI, especially osteoarthritis, are associated with diminished oral function and skeletal Class II and high-angle features in female patients with malocclusion. Although orthodontic treatment is not intended to manage TMDs, MRI-based structural characterization—when clinically appropriate—may aid in treatment planning by identifying underlying joint conditions. Full article

(This article belongs to the Special Issue Bruxism and Temporomandibular Disorders: Current Advances and Future Challenges)

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17 pages, 1886 KiB

Open AccessArticle

The Rainbow and the Umbrella of Temporomandibular Disorders—Total Antioxidant Capacity and Total Oxidant Status in Patients with Myofascial Pain with Referral

by Joanna Kuć, Anna Zalewska, Krzysztof Dariusz Szarejko, Małgorzata Żendzian-Piotrowska, Walery Tarnawski, Sara Zięba and Mateusz Maciejczyk

J. Clin. Med. 2025, 14(12), 4022; https://doi.org/10.3390/jcm14124022 - 6 Jun 2025

Viewed by 413

Abstract

Background: Temporomandibular disorders (TMDs) represent an umbrella term encompassing various musculoskeletal dysfunctions, including those affecting the masticatory muscles. This study aimed to compare the salivary levels of non-enzymatic antioxidants and redox balance between patients with temporomandibular myofascial pain with referral and matched [...] Read more.

Background: Temporomandibular disorders (TMDs) represent an umbrella term encompassing various musculoskeletal dysfunctions, including those affecting the masticatory muscles. This study aimed to compare the salivary levels of non-enzymatic antioxidants and redox balance between patients with temporomandibular myofascial pain with referral and matched healthy controls. Methods: The sample consisted of 44 individuals diagnosed with temporomandibular myofascial pain with referral and a matched control group. The procedure included a clinical examination based on the Diagnostic Criteria for Temporomandibular Disorders and saliva collection. Biochemical analysis included the assessment of reduced glutathione (GSH) levels, total antioxidant status (TAC), total oxidant status (TOS), and the oxidative stress index (OSI). Results: Patients with temporomandibular myofascial pain with referral exhibited higher levels of total oxidant status and glutathione. The mean value of total antioxidant capacity was lower, although the median was higher compared to the control group. No statistically significant differences were observed in the oxidative stress index between the two groups. Conclusions: Patients with temporomandibular myofascial pain with referral exhibit oxidative imbalance, reflected by increased salivary levels of non-enzymatic antioxidants, elevated total oxidant status, and significant differences in antioxidant capacity compared to healthy controls. Individually tailored physical activity, proper nutrition, and targeted supplementation may be necessary to maintain oxidative-antioxidant balance in this patient population. Full article

(This article belongs to the Special Issue Bruxism and Temporomandibular Disorders: Current Advances and Future Challenges)

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15 pages, 2049 KiB

Open AccessArticle

Gender Differences in Mouth Opening on Temporomandibular Disorder Patients—Implications for Diagnosis

by David Faustino Ângelo, Henrique José Cardoso, Ricardo São João, Carlos Brás-Geraldes, David Sanz, Francesco Maffia and Francisco Salvado

J. Clin. Med. 2025, 14(11), 3865; https://doi.org/10.3390/jcm14113865 - 30 May 2025

Viewed by 516

Abstract

Background/Objectives: Temporomandibular disorder (TMDs) patients often present limited mouth opening (LMO). A key diagnostic cutoff is a mouth opening threshold >40 mm. However, this universal cutoff may not accurately reflect gender anatomical variations. This study investigates gender-specific differences in maximum mouth opening (MMO) [...] Read more.

Background/Objectives: Temporomandibular disorder (TMDs) patients often present limited mouth opening (LMO). A key diagnostic cutoff is a mouth opening threshold >40 mm. However, this universal cutoff may not accurately reflect gender anatomical variations. This study investigates gender-specific differences in maximum mouth opening (MMO) to propose revised diagnostic criteria for LMO. Methods: A five-year prospective study was conducted from 1 August 2019 to 1 May 2024 in a Portuguese TMDs department. The patients’ gender, MMO, and LMO complaints with clinical validation were recorded. Statistical analyses, including Generalized Additive Models (GAMs) and Generalized Linear Models (GLMs), assessed the relationship between MMO and LMO, with gender-stratified comparisons. Results: In this study 1045 patients were included. The median (accompanied by the interquartile range [25th percentile–75th percentile]) MMO was lower in females (40 mm [34–45]) than in males (44 mm [40–48]). Patients presenting LMO complaints exhibited significantly reduced MMO values compared to those without LMO complaints (p < 0.001). Gender-specific thresholds emerged: for females, LMO was observed when MMO was ≤35 mm, while in males, LMO symptoms appeared when MMO was ≤38 mm. A “gray zone” of diagnostic uncertainty was identified between 36 and 37 mm for females and 38 and 42 mm for males. Conclusions: In this study we observed the gold standard cutoff for diagnosing MMO in female should be <35mm and for male <38mm. These findings suggest that a single LMO threshold does not account for gender-related anatomical differences, potentially leading to underdiagnosis in females and misclassification in males. Revising diagnostic criteria to incorporate gender-specific thresholds could enhance accuracy, improve early diagnosis, and promote personalized treatment strategies for TMDs patients. Further research incorporating additional variables such as age, dental occlusion, craniofacial structure, and body mass index is recommended to refine these diagnostic guidelines. Full article

(This article belongs to the Special Issue Bruxism and Temporomandibular Disorders: Current Advances and Future Challenges)

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14 pages, 675 KiB

Open AccessArticle

Double-Puncture Arthrocentesis in Arthrogenous TMJ Disorders: Bioviscosupplementation vs. Viscosupplementation a Randomized Controlled Trial

by David Faustino Ângelo, Henrique José Cardoso, David Sanz, Francesco Maffia, Marcella Sarkis, Beatriz Mota and Francisco Salvado

J. Clin. Med. 2025, 14(11), 3750; https://doi.org/10.3390/jcm14113750 - 27 May 2025

Viewed by 572

Abstract

Background/Objectives: Intra-articular injections of hyaluronic acid (HA) or platelet-rich plasma (PRP) have been used in the treatment of temporomandibular joint (TMJ) arthrocentesis to improve lubricative properties and influence regenerative processes. This study aimed to evaluate the potential clinical benefits of complementary bioviscosupplementation with [...] Read more.

Background/Objectives: Intra-articular injections of hyaluronic acid (HA) or platelet-rich plasma (PRP) have been used in the treatment of temporomandibular joint (TMJ) arthrocentesis to improve lubricative properties and influence regenerative processes. This study aimed to evaluate the potential clinical benefits of complementary bioviscosupplementation with hyaluronic acid (HA) and platelet-rich plasma (PRP) in patients undergoing double-portal TMJ arthrocentesis. Methods: A total of forty-six patients (33 females, 13 males; mean age of 45.83 ± 20.62 years) with arthrogenous temporomandibular disorders, identified through clinical and imaging examinations, were randomized into HA+PRP (23 patients) or HA-alone (23 patients) groups. The primary outcome variable was TMJ arthralgia; the secondary outcome was maximum mouth opening (MMO). All the outcome variables were assessed preoperatively (T0) and at several follow-ups (T1—1 month, T2—3 months, T3—6 months, T4—12 months follow-up). Results: The HA+PRP group presents lower TMJ arthralgia levels than the HA group at every follow-up moment (p < 0.05, r ≈ 0.3). At T3 and T4, the HA+PRP group presented a higher MMO average than the HA group (p = 0.03 and p = 0.02; r ≈ 0.3). At T4, the HA group’s success rate was lower than the HA+PRP group (65% vs. 96%), and a higher number of postoperative reinterventions were observed (35% vs. 4%). Conclusions: In this study, complementary intra-articular bioviscosupplementation (HA+PRP) following double-portal TMJ arthrocentesis was associated with better clinical outcomes regarding TMJ arthralgia reduction, MMO improvement, and reduced risk of future TMJ reintervention. Full article

(This article belongs to the Special Issue Bruxism and Temporomandibular Disorders: Current Advances and Future Challenges)

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17 pages, 1263 KiB

Open AccessArticle

Clinical Manifestations of Temporomandibular Disorders and Their Relationship with Sleep Disturbances and Emotional Disorders in a Spanish Pediatric Population: A Cross-Sectional Study

by Fanny Esther Tapia-Sierra, Jesús Miguel Ticona-Flores, Guillermo Reichard-Monefeldt, Naomi Elvira-Tapia, Nuria Esther Gallardo-López and Montserrat Diéguez-Pérez

J. Clin. Med. 2025, 14(10), 3599; https://doi.org/10.3390/jcm14103599 - 21 May 2025

Viewed by 523

Abstract

The etiology of temporomandibular disorders (TMDs) has been linked to various factors, including functional and psychological factors, which makes it difficult to identify associations between a single etiological factor and the signs and symptoms of TMDs. Objectives: This study aimed to describe [...] Read more.

The etiology of temporomandibular disorders (TMDs) has been linked to various factors, including functional and psychological factors, which makes it difficult to identify associations between a single etiological factor and the signs and symptoms of TMDs. Objectives: This study aimed to describe the presence of TMD symptoms and their relationship with sleep disturbances and emotional disorders in children and adolescents. Methods: This observational study included Spanish children aged between 8 and 13 years. The measurement instruments consisted of the BRUNI survey for sleep disorders and the Educational-Clinical Questionnaire: Anxiety and Depression (CECAD) survey. A clinical examination was subsequently performed following the DC/TMD guidelines for diagnosing TMDs. Frequencies, means, and standard deviations were applied, along with the prevalence ratio as a measure of association and the chi-square test. The significance level was set at 5%. Results: A total of 128 participants participated in the study with a mean age of 10.89 (±2.15) years. The prevalence of TMDs was 54%, while the most common symptoms were muscle pain at 26%, joint pain at 14%, and a combination of both at 14%. Children who presented muscle pain had a mean anxiety score of 44.87 (±11.85), whereas those without symptoms had a mean score of 36 (±10.78, and 0.03 p-value). The BRUNI index revealed that 78.13% of patients with TMDs had difficulty initiating and maintaining sleep, with a prevalence ratio (PR) of 3.57 (p-value 0.041). Conclusions: The present study reveals that temporomandibular disorders are common in children and adolescents, with 54% presenting at least one clinical sign or symptom. Emotional disturbances and sleep problems were also prevalent, affecting 41% and 56% of participants, respectively. Early interdisciplinary screening is essential to manage the co-occurrence of TMDs, emotional distress, and sleep problems in children. Full article

(This article belongs to the Special Issue Bruxism and Temporomandibular Disorders: Current Advances and Future Challenges)

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11 pages, 234 KiB

Open AccessArticle

Comparative Evaluation of Temporomandibular Disorders and Dental Wear in Video Game Players

by Cezar Ionita, Alexandru Eugen Petre, Alexandra Velicu and Adriana Sarah Nica

J. Clin. Med. 2025, 14(1), 31; https://doi.org/10.3390/jcm14010031 - 25 Dec 2024

Cited by 1 | Viewed by 918

Abstract

Background/Objectives: The increasing prevalence of video gaming has raised concerns about its potential impact on musculoskeletal health, particularly temporomandibular disorders (TMDs). This study aims to compare TMD symptoms, mandibular function, and dental wear between gamers and non-gamers among university students. Methods: [...] Read more.

Background/Objectives: The increasing prevalence of video gaming has raised concerns about its potential impact on musculoskeletal health, particularly temporomandibular disorders (TMDs). This study aims to compare TMD symptoms, mandibular function, and dental wear between gamers and non-gamers among university students. Methods: An observational study included 108 students aged 20 to 23 years, divided into gamers (n = 48) and non-gamers (n = 60). Participants completed questionnaires assessing TMD symptoms, gaming habits, and screen time. Clinical examinations measured mandibular movements, palpation-induced pain, and dental wear using the Smith and Knight Tooth Wear Index. Statistical analyses included independent t-tests, chi-square tests, Pearson’s correlations, and logistic regression. Seven comprehensive tables present the findings with p-values. Results: Gamers reported significantly higher screen time (Mean = 6.5 h/day) compared to non-gamers (Mean = 4.0 h/day; p < 0.001). Maximum unassisted mouth opening was greater in gamers (Mean = 48.31 mm) than in non-gamers (Mean = 46.33 mm; p = 0.04). Gamers exhibited a higher prevalence of pain on palpation of the masseter muscle (45.8% vs. 30.0%; p = 0.05). Dental wear scores were significantly higher in gamers for teeth 2.3 (upper left canine) and 3.3 (lower left canine) (p < 0.05). Positive correlations were found between hours spent gaming and maximum mouth opening (r = 0.25; p = 0.01) and dental wear (r = 0.30; p = 0.002). Logistic regression showed that gaming status significantly predicted the presence of TMD symptoms (Odds Ratio = 2.5; p = 0.03). Conclusions: Gamers exhibit greater mandibular opening, increased dental wear, and a higher prevalence of masticatory muscle pain compared to non-gamers. Prolonged gaming may contribute to altered mandibular function and increased risk of TMD symptoms. Further research is needed to explore underlying mechanisms and develop preventive strategies. Full article

(This article belongs to the Special Issue Bruxism and Temporomandibular Disorders: Current Advances and Future Challenges)

11 pages, 559 KiB

Open AccessArticle

Electromyographic Diagnostic Ranges Defining Temporomandibular Disorders and Healthy Individuals’ Results in Functional Clenching Index

by Grzegorz Zieliński and Michał Ginszt

J. Clin. Med. 2025, 14(1), 14; https://doi.org/10.3390/jcm14010014 - 24 Dec 2024

Cited by 2 | Viewed by 805

Abstract

Background: Temporomandibular disorders (TMDs) represent a significant public health issue, among which masticatory muscle pain is the most common. Current publications increasingly indicate surface electromyography (sEMG) as an effective diagnostic tool for muscle dysfunctions that may be employed in TMDs recognition. The [...] Read more.

Background: Temporomandibular disorders (TMDs) represent a significant public health issue, among which masticatory muscle pain is the most common. Current publications increasingly indicate surface electromyography (sEMG) as an effective diagnostic tool for muscle dysfunctions that may be employed in TMDs recognition. The objective of this study was to establish reference ranges for TMDs patients with masticatory muscle pain and healthy individuals in the electromyographic Functional Clenching Index (FCI) for the temporalis muscles (TAs) and masseter muscles (MMs). This research aimed to provide an additional diagnostic tool for TMDs patients. Methods: A total of 48 individuals (n = 30 women and n = 18 men) with the muscular painful form of TMDs were recruited alongside a numerically and gender-matched control group—healthy, pain-free controls. The Functional Clenching Indexwas calculated for both groups. Results: Data analysis revealed statistically significant differences with a very large effect size. Healthy individuals had higher FCI scores compared to those with TMDs. The healthy group exhibited higher threshold values compared to the TMDs group. Conclusions: For healthy individuals, the FCI ranges for TAs were between 58 and 145, while for MMs, between 72 and 210. Lower values may indicate muscle activation disorders and occur in patients with the painful, muscular form of TMDs. This is the first study to define reference ranges for electromyographic indices; therefore, caution is recommended, and the replication of this study on a larger and more culturally diverse sample is advised. Full article

(This article belongs to the Special Issue Bruxism and Temporomandibular Disorders: Current Advances and Future Challenges)

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Review

Jump to: Research, Other

20 pages, 569 KiB

Open AccessReview

Multimodal Approaches in the Management of Temporomandibular Disorders: A Narrative Review

by Izabela Dąbkowska, Lena Sobiech, Agata Czępińska, Adam Bęben, Karolina Turżańska and Piotr Gawda

J. Clin. Med. 2025, 14(12), 4326; https://doi.org/10.3390/jcm14124326 - 17 Jun 2025

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Abstract

Background/Objectives: Temporomandibular disorders (TMDs) are the most common cause of non-dental pain in the orofacial region. Due to the complex and multifactorial nature of TMD, a multidisciplinary approach is often required. The objective of this narrative review is to evaluate the effectiveness of [...] Read more.

Background/Objectives: Temporomandibular disorders (TMDs) are the most common cause of non-dental pain in the orofacial region. Due to the complex and multifactorial nature of TMD, a multidisciplinary approach is often required. The objective of this narrative review is to evaluate the effectiveness of multimodal therapies in the management of TMD. Methods: A literature search was performed using a combination of keywords: “TMD”, “TMJ”, “disorders”, “manual therapy”, “physical therapy”, “dry needling”, “botulinum toxin”, “Botox”, “splint”, and “psychotherapy”. The search was conducted in the PubMed, Google Scholar, and Scopus databases, focusing on studies involving human subjects. Results: The included studies reported that the use of multimodal approaches—such as physiotherapy, botulinum toxin injections, occlusal splints, and/or psychotherapy—led to symptom improvement or complete resolution in patients with TMD. Conclusions: Temporomandibular disorders are complex conditions with a multifactorial etiology involving both somatic and psychological components. Given the wide range of symptoms and the functional connections of the temporomandibular joint with the nervous, muscular, and skeletal systems—including the cervical spine—effective treatment of TMD requires a multidisciplinary strategy. Full article

(This article belongs to the Special Issue Bruxism and Temporomandibular Disorders: Current Advances and Future Challenges)

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17 pages, 1199 KiB

Open AccessReview

The Importance of Genetic Background and Neurotransmission in the Pathogenesis of the Co-Occurrence of Sleep Bruxism and Sleep-Disordered Breathing—Review of a New Perspective

by Joanna Smardz, Andrej Jenca, Jr. and Sylwia Orzeszek

J. Clin. Med. 2024, 13(23), 7091; https://doi.org/10.3390/jcm13237091 - 23 Nov 2024

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Abstract

Sleep bruxism (SB) and sleep-disordered breathing (SDB) are two prevalent conditions that significantly impact overall health. Studies suggest that up to 49.7% of individuals with SDB also exhibit symptoms of SB. This review aims to provide a comprehensive analysis of the role of [...] Read more.

Sleep bruxism (SB) and sleep-disordered breathing (SDB) are two prevalent conditions that significantly impact overall health. Studies suggest that up to 49.7% of individuals with SDB also exhibit symptoms of SB. This review aims to provide a comprehensive analysis of the role of genetic background and neurotransmission in the pathogenesis of the co-occurrence of SB and SDB. It seeks to synthesize current knowledge, highlight gaps in the existing literature, and propose a new perspective that integrates genetic and neurobiological factors. This review shows that both SB and SDB may be influenced by a combination of genetic, neurochemical, and environmental factors that contribute to their shared pathophysiology. The key neurotransmitters—dopamine, serotonin, and GABA—may play a significant role in their co-occurrence by regulating motor activity, sleep architecture, and respiratory control. Understanding genetic and neurochemical mechanisms may allow for more precise diagnostic tools and more personalized treatment approaches regarding SB and SDB. Clinically, there is a need for interdisciplinary collaboration between sleep specialists, dentists, neurologists, and geneticists. There is also a need to conduct large-scale genetic studies, coupled with neuroimaging and neurophysiological research, uncovering additional insights into the shared mechanisms of SB and SDB. Full article

(This article belongs to the Special Issue Bruxism and Temporomandibular Disorders: Current Advances and Future Challenges)

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Other

Jump to: Research, Review

12 pages, 677 KiB

Open AccessSystematic Review

Quality of Life Outcomes Following Total Temporomandibular Joint Replacement: A Systematic Review of Long-Term Efficacy, Functional Improvements, and Complication Rates Across Prosthesis Types

by Luis Eduardo Almeida, Samuel Zammuto and Louis G. Mercuri

J. Clin. Med. 2025, 14(14), 4859; https://doi.org/10.3390/jcm14144859 - 9 Jul 2025

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Abstract

Introduction: Total temporomandibular joint replacement (TMJR) is a well-established surgical solution for patients with severe TMJ disorders. It aims to relieve chronic pain, restore jaw mobility, and significantly enhance quality of life. This systematic review evaluates QoL outcomes following TMJR, analyzes complication profiles, [...] Read more.

Introduction: Total temporomandibular joint replacement (TMJR) is a well-established surgical solution for patients with severe TMJ disorders. It aims to relieve chronic pain, restore jaw mobility, and significantly enhance quality of life. This systematic review evaluates QoL outcomes following TMJR, analyzes complication profiles, compares custom versus stock prostheses, explores pediatric applications, and highlights technological innovations shaping the future of TMJ reconstruction. Methods: A systematic search of PubMed, Embase, and the Cochrane Library was conducted throughout April 2025 in accordance with PRISMA 2020 guidelines. Sixty-four studies were included, comprising 2387 patients. Results: Primary outcomes assessed were QoL improvement, pain reduction, and functional gains such as maximum interincisal opening (MIO). Secondary outcomes included complication rates and technological integration. TMJR consistently led to significant pain reduction (75–87%), average MIO increases of 26–36 mm, and measurable QoL improvements across physical, social, and psychological domains. Custom prostheses were particularly beneficial in anatomically complex or revision cases, while stock devices generally performed well for standard anatomical conditions. Pediatric TMJR demonstrated functional and airway benefits with no clear evidence of growth inhibition over short- to medium-term follow-up. Complications such as heterotopic ossification (~20%, reduced to <5% with fat grafting), infection (3–4.9%), and chronic postoperative pain (~20–30%) were reported but were largely preventable or manageable. Recent advancements, including CAD/CAM planning, 3D-printed prostheses, augmented-reality-assisted surgery, and biofilm-resistant materials, are enhancing personalization, precision, and implant longevity. Conclusions: TMJR is a safe and transformative treatment that consistently improves QoL in patients with end-stage TMJ disease. Future directions include long-term registry tracking, growth-accommodating prosthesis design, and biologically integrated smart implants. Full article

(This article belongs to the Special Issue Bruxism and Temporomandibular Disorders: Current Advances and Future Challenges)

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17 pages, 1211 KiB

Open AccessHypothesis

Quo Vadis Temporomandibular Disorders? By 2050, the Global Prevalence of TMD May Approach 44%

by Grzegorz Zieliński

J. Clin. Med. 2025, 14(13), 4414; https://doi.org/10.3390/jcm14134414 - 20 Jun 2025

Viewed by 732

Abstract

Background/Objectives: Currently, temporomandibular disorders (TMDs) represent a significant public health concern, affecting approximately 34% of the global population. The primary aim of this study was to determine the prevalence of TMDs in the year 2050. A secondary objective was to estimate the prevalence [...] Read more.

Background/Objectives: Currently, temporomandibular disorders (TMDs) represent a significant public health concern, affecting approximately 34% of the global population. The primary aim of this study was to determine the prevalence of TMDs in the year 2050. A secondary objective was to estimate the prevalence for the years 2030, 2075, and 2100. Methods: The methodology of a prognostic study was replicated and adapted to develop prevalence projections for TMDs, utilising the most recent meta-analysis of the global prevalence of temporomandibular disorders and analyses conducted within the R environment. Results: Projections indicate a gradual increase in the global prevalence of TMDs over the coming decades. In 2030, the estimated prevalence is 39% (95% confidence interval: 34–44%). This figure is expected to rise to 41% [36–46%] by 2040 and reach 44% [39–49%] by 2050. The upward trend continues, with projections suggesting a prevalence of 47% [42–52%] in 2075 and 49% [44–54%] by 2100. These data highlight a steadily increasing global burden of TMDs. Conclusions: By the year 2050, the global prevalence of TMDs is projected to reach 44%, which, according to estimates, corresponds to approximately 4,252,160,000 individuals. By 2030, 39% of the population is projected to experience TMDs. By 2075, the global TMD prevalence is expected to rise to 47%, and, by 2100, it could increase further to 49% of the global population. Urbanisation affects TMD prevalence in a region-dependent manner; a significant decrease was observed in Asia, while, in the Americas and Europe, the association was negligible. Globally, the lack of a clear impact of urbanisation on TMD occurrence suggests the influence of environmental and cultural factors. Full article

(This article belongs to the Special Issue Bruxism and Temporomandibular Disorders: Current Advances and Future Challenges)

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12 pages, 1995 KiB

Open AccessSystematic Review

The Co-Occurrence of Temporomandibular Disorders in Patients Diagnosed with Tinnitus: A Systematic Review with Meta-Analysis

by Michał Bury, Kacper Nijakowski, Anna Majewska, Jakub Jankowski, Anna Surdacka and Dorota Hojan-Jezierska

J. Clin. Med. 2025, 14(6), 1836; https://doi.org/10.3390/jcm14061836 - 8 Mar 2025

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Abstract

Background/Objectives: Persistent and distressing tinnitus and TMDs may significantly impair the quality of patients’ lives. Problems are particularly severe for those who experience both. Although the exact causes of this association are not fully understood, several hypotheses connect TMD conditions with otological symptoms. [...] Read more.

Background/Objectives: Persistent and distressing tinnitus and TMDs may significantly impair the quality of patients’ lives. Problems are particularly severe for those who experience both. Although the exact causes of this association are not fully understood, several hypotheses connect TMD conditions with otological symptoms. Methods: The systematic review presented involved records published between 1 January 2004 and 27 November 2024, in the databases PubMed, Scopus, and Web of Science, according to the PRISMA guidelines. The search queries included “temporomandibular disorder” and “tinnitus”. Inclusion and exclusion criteria were predefined according to PECOS. A risk of bias assessment and meta-analyses were performed. The study’s protocol was registered in PROSPERO (CRD42024533293). Results: Eleven studies included in this review fulfilled all the predefined criteria. In a sample of 114,071 tinnitus patients, 50.99% (95% CI: 33.31–68.54) also had coexisting TMDs. Furthermore, tinnitus patients had more than 2.2 times higher odds of having TMDs compared to the control group (p = 0.002 for random effects). The absence of data regarding randomisation, blinding, and sample size justification was the most frequent risk of bias. Conclusions: Tinnitus frequently co-occurs in patients who suffer from TMDs. It is essential to expand the diagnostic evaluation of patients to confirm its presence and assess its impact on their quality of life. Additionally, dental consultation should be considered to evaluate patients about TMD signs and symptoms when suffering from tinnitus. Full article

(This article belongs to the Special Issue Bruxism and Temporomandibular Disorders: Current Advances and Future Challenges)

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