Bruxism is another of the most common oral problems. In this post we talk about thecauses, treatment and consequencesfrom involuntarily clenching your teeth.
1) What is bruxism?
Bruxism is defined as a parafunctional activity characterized by involuntary clenching or grinding of the teeth, either during sleep or during the day.
In many cases, bruxism is not perceived by the patient themselves and is usually discovered through its clinical consequences (dental wear, jaw pain) or through observation by third parties (nighttime noises).
It is now recognized that bruxism is a behavior of origin multifactorial and does not always imply an underlying pathology; that is, it can occur in healthy people without causing harm, although in others it causes dental lesions and significant temporomandibular disorders.
2) Prevalence of bruxism
2a) Global prevalence of bruxism
It is estimated that the combined global prevalence of bruxism (adding the sleep and wake times) is around 22%. These figures, however, vary by geographic region. For example, the prevalence of nocturnal bruxism is higher in North America (~31%), followed by South America (~23%), Europe (~21%) and Asia (~19%).
2b) Prevalence of bruxism by sex
Bruxism is more common in women than in men. In women, the incidence of sleep bruxism increases significantly in adulthood compared to younger ages, while no such variation with age was observed in men. In contrast, for waking bruxism, age was not a determining factor in either sex.
2c) Prevalence of bruxism by age
In general, children and adolescents show relatively high rates of bruxism (some series mention 14–20% in children), which tend to decrease in adulthood and become less frequent in older adults.
In young children, physiological bruxism is considered to exist, related to the normal stimulation and development of the face, mouth, and teeth in children. This bruxism usually occurs during primary teeth and gradually disappears as the permanent teeth emerge. It can also be related to anxiety, nervousness, or stress in childhood.
3) Types of bruxism
Depending on the form in which it is presented bruxism, the following can be differentiated:
3a) Clenching bruxism
It is generated when the masticatory muscles contract when clenching your teeth. Since there is no slippage between the teeth, there is less noticeable wear.
3b) Grinding or rubbing bruxism
In this case, friction is generated between the teeth contract and relax the masticatory muscles. This form of bruxism can cause severe tooth wear or attrition.
As we mentioned at the beginning of the article, we can also classify it depending on the time of day in which this disorder occurs:
3c) Diurnal bruxism or wakefulness
As its name suggests, it consists of unconsciously clenching the teeth while awake. It usually manifests itself with other habits such as clenching your lips between your teeth or biting your nails.
3d) Nocturnal or sleep bruxism
It occurs during sleeping hours. It may be related to the Chronic Obstructive Sleep Apnea Syndrome or sleep apneas. It usually causes tooth, muscle and joint pain upon waking.
4) Etiology of bruxism and pathophysiological mechanisms
The cause of bruxism is recognized as multifactorial and complex. The latest scientific evidence reinforces that there is no single cause, but rather an interaction of factors neurological, genetic, psychological and external. A conceptual distinction is made between primary bruxism (idiopathic, without identifiable medical cause) and secondary bruxism, associated with other conditions such as certain neurological disorders (especially of the extrapyramidal system, such as Parkinson’s disease or other movement disorders) and psychiatric, like the obsessive-compulsive disorder (OCD), he generalized anxiety disorder and the schizophrenia, and the use of drugs or substances affecting the central nervous system. These facts suggest an important involvement of the neurochemical pathways –in particular alterations in dopamine and serotonin levels.
4a) Genetics can predispose to bruxism
Numerous studies have shown that bruxismmay have a genetic originand it can be shared between different members of the same family.
A meta-analysis of twin studies published in 2024 showed that sleep bruxism concordance is significantly higher in monozygotic twins than in dizygotic twins. In other words, identical twins tend to share the habit of nighttime bruxing more frequently than fraternal twins, suggesting an influence hereditary genetics in the appearance of bruxism.
4b) Psychological factors that cause bruxism
The psychological factors and personality have been repeatedly implicated as triggers, especially in daytime bruxism.
He stress psychological, the anxiety and certain traits (e.g., competitive people or those with a tendency toward muscular hyperactivity) are associated with a higher prevalence and intensity of bruxism.
Stress and anxiety activate the sympathetic nervous system, preparing the body for “fight or flight.” This activation can increase muscle tension, including that of the jaw muscles, which can lead to teeth grinding and clenching.
A recent study confirmed the strong association between bruxism, temporomandibular disorders and psychological factors: that is, clenching/grinding episodes frequently occur under the influence of stress or anxiety, which causes overload of the masticatory structures (muscles, joint) and can lead to typical symptoms of temporomandibular dysfunction.
Along the same lines, it has been observed that bruxism linked to psychological factors tends to manifest itself more during waking hours (for example, the habit of clenching the jaw in stressful work situations), while other neurophysiological mechanisms also influence sleep.
In stressful situations, some people develop unconscious habits or behaviors such as nail biting or teeth clenching.
4c) Relationship between sleep disorders and bruxism
From the point of view neurophysiological, sleep bruxism has been linked to microdespertares or brief activations of the autonomic nervous system during the sleep cycle, especially in the non-REM phase. Studies with polysomnography (sleep recording) have shown that episodes of nocturnal bruxism are often preceded by an abrupt increase in heart and respiratory rate, indicative of a cerebral micro-alert, even when the individual does not fully awaken. These micro-awakenings occur with a certain periodicity (several times per hour) and could reflect the body’s defense mechanisms against some disturbance (such as partial airway obstruction, vivid dreams, etc.). In fact, nocturnal bruxism frequently coexists along with other sleep disorders, such as obstructive sleep apnea syndrome, restless legs syndrome, REM sleep behavior disorders, and even other parasomnias. A pathophysiological hypothesis suggests that in some cases bruxism could be a reflex response that seeks“solve”a problem during sleep: for example, clenching and protruding the jaw tenses the muscles of the upper airway, which could temporarily improve pharyngeal patency in people with sleep apnea; or the increased muscle activity and salivation associated with bruxism could“protect”against nocturnal gastroesophageal reflux and dry mouth. Although these theories require further evidence, clinical practice has shown that patients with sleep disturbances or high stress levels present bruxism more frequently.
4d) Is there a relationship between bite and teeth alignment and bruxism?
Contrary to what is widely reported today, the dental occlusion (i.e. the way we bite and the alignment of the teeth) in the cause of bruxism has been questioned by recent literature.
It was once believed that dental interferences or malocclusions caused clenching or grinding, but today occlusal factors are considered to have an impact limited or inconclusive in the origin of bruxism, especially in sleep bruxism. In other words, correcting the bite alone rarely eliminates centrally based bruxism. However, occlusal alterations could act as a contributing factors by aggravating the consequences of bruxism (e.g. accelerating dental wear or overloading the TMJ).
4e) Other diseases that cause bruxism
There are also other diseases that are closely related to bruxism. In this group we include allergies, dementia, Parkinson’s, hyperactivity, gastroesophageal reflux disorder, epilepsy, night terrors or other sleep-related problems.
Likewise, some psychiatric medications (such as antidepressants) and stimulant substances such as tobacco, alcohol, caffeine orconsumption of certain types of drugsmay promote the development of this disorder.
In short, each patient may present a different combination of triggers, so a comprehensive evaluation (psychological, neurological, dental) is essential to understand the origin of their bruxism and guide management.
5) Relationship between bruxism and temporomandibular disorders (TMJ)
The association between bruxism and temporomandibular disorders (TMD) –a group of conditions affecting the temporomandibular joint (TMJ) and/or masticatory muscles, causing orofacial pain, joint noises, and functional disturbances– has been the subject of numerous studies. In practice, it is well known that bruxing patients often develop jaw pain or joint dysfunction, and vice versa, many patients with TMJ syndrome report a history of teeth clenching or grinding. The most recent scientific evidence confirms a significant positive relationship between both phenomena.
A meta-analysis published in 2023 quantified this association in a forceful manner: the presence of bruxism more than doubles the likelihood of developing a TMJ disorder compared to not bruxing. Simply put, bruxism acts as a relevant risk factor to develop temporomandibular dysfunction.
5) Relationship between bruxism and temporomandibular disorders (TMJ)
5a) Muscle pain caused by bruxism
Mechanistically, the muscle overexertion Repetitive clenching can lead to fatigue and overactivity of the masseter and temporal bones, triggering muscle pain and trigger points. In turn, excessive stress on the joint during grinding episodes can contribute to the displacement of the articular disc or microtrauma to the mandibular condyles, promoting joint inflammation and the development of clicking, locking, or degenerative disorders.
5b) Bruxism as a contributing factor to TMD
However, it is important to note that the bruxism-TMD relationship is not necessarily causal in 100% of cases, but rather a contributing or exacerbating factor. There are individuals with intense bruxism who surprisingly do not develop significant TMD, and vice versa, patients with TMD who do not report bruxism (which indicates that other genetic, postural, traumatic, etc. factors also intervene in TMD).
5c) Poor alignment of teeth or tooth loss can aggravate bruxism
Although it has traditionally been considered that the problems of dental occlusion (poor alignment of the teeth) may be a cause of bruxism, but recent scientific evidence does not support this theory. While some people with malocclusions may experience bruxism, no direct, consistent relationship has been found between bite alterations and the onset of this disorder.
These local factors such as dental malocclusions or tooth loss. They can aggravate the impact of bruxism on the TMJ. For example, Class III skeletal malocclusions (projected jaw) or the absence of multiple teeth alter mandibular biomechanics and are associated with a higher incidence of joint dysfunction. In these patients, if bruxism is also present, TMJ symptoms tend to be more pronounced. Therefore, in the clinical context, a bruxist with occlusal disorders should be considered at high risk for developing TMJ disorders. Therefore, a detailed occlusal and joint assessment of patients with chronic bruxism is recommended.
For all these reasons, in clinical practice it is recommended to address in a integral the bruxist patient, monitoring for early signs of joint dysfunction (pain, noise, limited opening) and establishing early preventive or therapeutic measures to protect the TMJ.
6) How do I know if I have bruxism?
One of the problems with bruxism, especially nocturnal bruxism, is the difficulty in detecting it. Because it involves involuntary tooth movement, bruxers are often unaware of their condition until someone tells them or the consequences begin to be noticeable. At first glance. One of the most common ways to diagnose and manage it is by visiting the dentist regularly. A qualified dental professional can detect this problem during a routine checkup.
7) What are the consequences of clenching your teeth?
Although bruxism can be mild, sporadic and have no consequences, in the most serious cases. It can lead to many problems such as wear and tear, breakage, tooth sensitivity, muscle pain, jaw pain, ear pain and/or headaches, or sleep disorders.
These consequences can affect both the dental health like the quality of life of the patient.
Major complications include:
7a) Grinding your teeth can cause tooth wear and sensitivity
Although there are different onestypes of wear, bruxism causes the so-called dental attrition, a deterioration of tooth surfaces due to contact between them.
Grinding your teeth can also deteriorate the enamel, the main protective layer of the teeth. Over time, this can lead to increased sensitivity of the teeth to cold and heat, or even pain.
Furthermore, significant tooth wear leads to enamel loss, dentin exposure, tooth sensitivity, and fractures of teeth or restorations. This wear is especially noticeable in nocturnal bruxism, when teeth grinding occurs involuntarily and repeatedly during sleep.
7b) Sleep disorders caused by bruxism
Sleep or nocturnal bruxism is closely linked to other sleep disorders. Thus, patients who clench may be more prone to snore or even to the sleep apnea (pauses in breathing while sleeping)
In addition, nocturnal bruxism can disrupt sleep, resulting in insomnia or poor-quality sleep, affecting daytime fatigue and reducing overall daytime performance. This is especially problematic for those with severe bruxism, as teeth grinding can generate annoying noises that disrupt both the patient’s sleep and that of their partner.
7c) Temporomandibular dysfunction and its relationship with bruxism
Prolonged bruxism can lead to disorders of the ATM, which include temporomandibular joint pain, muscle pain, and difficulty chewing or opening the mouth. These disorders are very common among patients with bruxism, especially those with nocturnal bruxism.
One of the most obvious symptoms of bruxism is frequently waking up with pain in the jaw, neck, ear, and/or head. This is because these involuntary movements can overload the temporomandibular joint, the joint located on each side of the jaw that allows us to speak and chew. Over time, this can even lead to temporomandibular joint (TMJ) dysfunction or cause contractures, overload, or even injuries to other parts of the body. In fact, treating bruxism is especially important for elite athletes, as it can increase the risk of injury.
7d) Pain caused by clenching teeth
Constant clenching of the teeth can cause pain in the masticatory muscles, in the jaw and even in the neck Masseter muscle hypertrophy is common in those who suffer from bruxism.
7e) The psychological impact of bruxism
Bruxism can cause anxiety and worry on dental health, which in turn can contribute to more stress and worsen the problem. Patients may also develop feelings of discomfort due to facial and muscle pain associated with bruxism.
8) Current and emerging diagnostic methods of bruxism
Diagnosing bruxism has historically been challenging, as much of the activity occurs unconsciously (particularly during sleep) and there is no single, simple clinical test that infallibly confirms it. However, in recent years, the methods have been refined diagnostic criteria and technological tools have been developed that improve detection.
8a) The need for clinical evaluation of the patient with bruxism
In practice, the first step to identify bruxism is through the clinical evaluation and history of the patient. This includes the self-report or the third-party report: For example, asking the patient if they notice jaw tension or pain upon waking, or if anyone has heard grinding sounds during the night. There are standardized questionnaires and assessment scales that help quantify the frequency and perceived impact of the habit. Along with the history, the dentist performs an examination looking for clinical signs indicative of bruxism, such as facets of dental wear unusual (not explained by age or diet alone), hypertrophy of the masseter muscles (volume increased by continuous exercise), print lines or bites on the mucosa and tongue, fractures of dental restorations without apparent cause, and limitation or pain upon palpation of the mandibular muscles. If the patient reports joint or muscle pain, the TMJ is also examined for associated noises or movement restrictions.
8b) Instrumental tools to diagnose bruxism
Among the instrumental tools to diagnose bruxism, the standard is the polysomnography (PSG) with audiovisual recording. PSG involves monitoring the patient during sleep in a specialized laboratory, measuring muscle bioelectrical activity (electromyography of the masseter/temporal muscles), mandibular movements, respiratory flow, cardiac output, and brain activity, among other parameters. PSG allows detect accurately sleep bruxism events (called sleep bruxism events)rhythmic masticatory activity), differentiating them from other orofacial movements during sleep. However, this test is expensive and difficult to access (requiring equipment and personnel from a sleep laboratory), so it is not routinely used in all patients. In population-based studies using PSG, the prevalence of nocturnal bruxism was much higher than that reported by questionnaires (e.g., one study found up to 43% of individuals with bruxism episodes detected by PSG, compared with ~21% by self-report), indicating that many people are unaware of their bruxism unless investigated with instruments.
8c) Methods for home recording of bruxism
In addition to PSG, less complex methods have been developed for home searches. There are devices intraorales similar to a splint or mouth guard that contain pressure sensors, electromyography sensors, or a very thin, dye-coated plate that marks dental movements, which the patient wears at night to record clenching/grinding activity. Similarly, there are portable electromyography which adhere to the skin over the mandibular muscles and record contractions while the patient sleeps.
8d) Mobile applications for bruxism monitoring
Regarding daytime bruxism, the direct observation is difficult outside the office. A recent strategy is the use of mobile monitoring applications momentary assessment-based apps: apps that send random reminders to the patient throughout the day asking whether they are currently clenching their teeth, thus creating a daily record of conscious bruxism frequency. Similarly, biofeedback devices (e.g., small sensors placed on the forehead or temples that vibrate or beep when they detect sustained muscle tension) are emerging as both diagnostic and therapeutic tools for waking bruxism.
9) How to treat bruxism
Now that we understand what bruxism is, what causes it, and what consequences it has, it’s time to delve deeper into the treatments for this oral disorder. It’s important to keep in mind that. Sometimes the problem may go away on its own, so no additional elements are necessary. However, in cases of chronic bruxism, it is necessary to try to restore proper occlusion.
9a) Orthodontic treatment to combat teeth grinding
Since certain malocclusions can aggravate joint overload, in patients with marked bone discrepancies or premature contacts, a orthodontic treatment or even orthognathic (surgical) as part of comprehensive management. Bite correction (e.g., uncrossing a deep bite or aligning severe crowding) may improve the distribution of forces during the function and potentially reduce the intensity of the parafunction in some cases. However, it is important to manage expectations: Correcting the occlusion does not guarantee that bruxism will disappear, since, as discussed, the habit has core components independent of the bite. However, in a bruxing patient with malocclusion, aligning teeth and optimizing the maxilla/mandible relationship may alleviate other stress factors or neuromuscular compensation. For example, a patient with multiple molar loss (and therefore collapse of the vertical dimension) may brux more in an unconscious attempt to achieve occlusal stability; in such a case, the prosthetic or orthodontic rehabilitation restoring the lost dimension could reduce that trigger.
9b) The discharge splint, an aid in the treatment of bruxism
Classically the cornerstone in the dental management of bruxism is the occlusal splints (nighttime offloading plates). These are removable, rigid acrylic resin devices that the patient typically wears during sleep. Their primary purpose is protect teeth from wear and distribute occlusal forces more evenly to reduce stress on individual teeth. Splints can also contribute to a slight decrease in nocturnal muscle activity by modifying mandibular posture, although they do not always eliminate bruxism completely.
To develop night guards, molds or digital scans of the mouth are taken to study the case, and the appropriate device is then prepared for each denture. The patient can use it during the day, at night, or both, depending on the severity of the bruxism and the dentist’s recommendations.
9c) Head, neck and mouth physiotherapy
A temporomandibular joint physical therapy specialist can help decongest and relax the masticatory muscles, thus reducing muscle fatigue and headaches. It can also teach postural re-education.
The temporomandibular joint physiotherapy includes manual techniques for stretch and relax the masticatory muscles, trigger point massages of the masseter/temporalis, gentle jaw mobilizations and mandibular proprioception exercises. These interventions seek to reduce the muscle pain and improve the range of motion of the jaw when it is limited. Regular manual therapy and certain home exercises (such as controlled opening routines, lateral movements against resistance, etc.) help relieve accumulated muscle tension and reduce the frequency of headaches and associated neck discomfort.
Another technique used is the dry needling the dry puncture a of the masticatory muscles, which consists of introducing fine needles (similar to those used in acupuncture) into the contracted muscle points to achieve their reflected relaxation. This method has been shown effectiveness in reducing myofascial pain and masseter hyperactivity in bruxist patients, although – like Botox – its effect is temporary and usually requires several maintenance sessions.
9d) Repair teeth worn by bruxism
In addition to the treatments mentioned above, it must be taken into account that if bruxism has already caused severe wear of the teeth,the dentist may need to reshape the chewing surfaces of the teeth. Restorations such as inlays, crowns, etc. may be necessary to repair the damage and restore lost tooth structure.
It is essential to emphasize to the bruxing patient the need for regular check-ups: splints must be adjusted and replaced if they become worn, and any dental rehabilitation performed may also be subject to excessive forces, requiring maintenance.
9e) Recommended medication for the treatment of bruxism
Although medication is not usually used to treat this problem, some professionals may recommend the use of use of muscle relaxants and/or medications for anxiety and stress. In some severe cases, the use of injections may be advised botox in the masticatory muscles to control this disorder.
Among the systemic drugs, the muscle relaxants and night-acting anxiolytics are the most commonly used. For example, low doses ofbenzodiazepines such as clonazepam before bedtime may reduce jaw muscle activity during sleep and improve sleep quality, although their prolonged use is limited by the risk of dependence and daytime sleepiness. Other drugs tested include certain tricyclic antidepressants (e.g. amitriptyline in low doses) that in addition to improving bruxism can relieve chronic facial pain, and some dopamine agonists the beta-blockers in cases related to movement disorders or associated cardiovascular stress, respectively. Another therapy is the use of botulinum toxin type A (e.g., Botox) injected into the masseter and temporalis muscles Botulinum toxin causes a reversible blockade of neuromuscular transmission, inducing a partial relaxation of the muscles. However, its effects are temporary (usually lasting 3 to 6 months) and require periodic reinjections to maintain the benefit. Furthermore, they must be dosed carefully to avoid excessively weakening the muscles (which could hinder normal chewing) or causing unwanted aesthetic atrophy of the face.
9f) Psychological and behavioral therapies to combat teeth clenching
As we’ve already mentioned, bruxism is closely related to psychological factors such as stress and anxiety. Therefore, managing these triggers can help combat this disorder. Therefore, it is advisable to: Avoid life stressors and do relaxation exercises before sleeping.
Psychological interventions are an important pillar, especially for daytime bruxism. Techniques of cognitive behavioral therapy (CBT) focused on stress and anxiety management, they have shown benefits in reducing the patient’s overall tension and the frequency of clenching episodes patient education It is essential to explain the multifactorial nature of bruxism, identify with him the possible triggers in his daily life (for example, work situations, driving, studying) and train him in coping strategies. A useful technique is training in mandibular awareness: The patient is taught to recognize when he or she is clenching his or her jaw during the day and to practice a “resting” posture (lips together, teeth separated, tongue on the palate) that relieves the TMJ. The hypnotherapy and deep relaxation techniques before sleep for patients with nocturnal bruxism associated with anxiety, with some anecdotal reports of success. An interesting development in the pediatric population is the incorporation of sleep hygiene habits and mindfulness: A recent trial showed that improving bedtime routines (avoiding screens, establishing regular schedules) along with simple mindfulness and relaxation exercises in children achieved reduce the frequency of sleep bruxism significantly.
9g) Home remedies to combat bruxism
In addition to everything mentioned so far, there are some home remedies that can help with this problem. Therefore, it is recommendedavoid eating hard foods and chewing gum and increase the water intake during the day. Before going to sleep, you can applying ice or moist heat to the jaw muscles and do exercises, stretching and/or massages in the area of influence of the temporomandibular joint.
In conclusion, the treatment of bruxism frequently requires combining strategies to address its different aspects: protecting the dentition, reducing neuromuscular hyperactivity, and managing the psychosocial triggering factors. An approachAlonemechanic orAlonepsychological approach often falls short. The most recent reviews emphasize that a more multi-disciplinary: The best results are obtained by integrating dental, physical and psychological measures tailored to each patient.
If you live in A Coruña and you suffer from bruxism or another problem related to oral health, the team of professionals at Pardiñas Dental Clinic is at your disposal.
