How do I know if I grind my teeth?

Many people do not know until their dentist points it out during a routine examination. Signs your dentist looks for include flattened or worn biting surfaces, chipped enamel, scalloped edges on the tongue, and evidence of tooth sensitivity. You may also notice jaw soreness or headaches upon waking.

Will a night guard eliminate my jaw pain?

Night guards can significantly reduce muscle fatigue and joint strain by limiting the forces transmitted during grinding. Many patients report improvement in morning jaw pain and headaches. However, if significant temporomandibular joint dysfunction is present, additional treatment may be needed alongside the appliance [^4].

Can I buy a night guard at the pharmacy?

Over-the-counter guards are available but are not considered an adequate long-term solution for most cases of significant bruxism. They are less durable, fit less precisely, and some designs may inadvertently worsen muscle activity. A custom appliance made by your dentist is the clinically recommended option [^2].

How long does a night guard last?

A well-maintained custom hard acrylic night guard typically lasts between three and five years, depending on the severity of grinding. Signs it needs replacement include visible holes ground through the material, cracking, or a distorted fit.

Does a night guard help with TMJ pain?

The evidence supports a meaningful benefit for many patients. By reducing the load transmitted to the temporomandibular joint during sleep, a properly designed splint can decrease joint inflammation and associated pain [^4]. The degree of benefit depends on the severity and cause of the TMJ problem.

Is there a difference between an upper and lower night guard?

Both designs can be effective. Upper guards are more commonly prescribed and tend to be more stable because the upper arch is typically wider. Lower guards are sometimes preferred for patients who find upper appliances trigger a gag reflex. Your dentist will recommend the most appropriate design based on your specific bite and clinical needs [^2].

What happens if I do not treat bruxism?

Left unmanaged, bruxism leads to progressive tooth wear that can require extensive and costly restorative treatment, including crowns, veneers, or in severe cases, full-mouth rehabilitation. The earlier protective measures are in place, the more tooth structure can be preserved. This is the core principle of conservative dentistry. ---

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THE SCIENTIFIC JOURNAL

Why Your Dentist Might Recommend a Night Guard

By Dr. Khalid Aletaibi11 February 20267 min read

QUICK ANSWER

If your dentist has suggested a night guard, it is very likely because they have noticed signs of bruxism, the clinical term for grinding or clenching your teeth. Bruxism affects an estimated 8 to 31 percent of adults worldwide ^[1], and while it often happens during sleep without any awareness, the damage it causes to tooth structure, jaw muscles, and joints can accumulate over years. A night guard is one of the most well-studied tools for managing that damage ^[2].

What Is Bruxism and Why Does It Matter?

Bruxism is not simply a bad habit. It is a multifactorial oral parafunctional activity that researchers classify into two distinct types: sleep bruxism, which occurs during sleep, and awake bruxism, which occurs during waking hours, often unconsciously ¹. Both can cause damage, but sleep bruxism tends to generate substantially more force because the conscious control that limits clenching during the day is absent.

The consequences of untreated bruxism are well documented. Tooth enamel, the hardest substance in the human body, is not renewable. Once it is worn away through grinding, the underlying dentine becomes exposed, leading to sensitivity, discoloration, and a significantly increased risk of fracture ². Beyond the teeth themselves, the temporomandibular joint (TMJ) and the muscles of mastication bear considerable strain, which can translate into jaw pain, limited mouth opening, clicking or popping sounds, and headaches concentrated around the temples ³.

How Common Is Bruxism?

A 2024 systematic review published in the Journal of Clinical Medicine analyzed global prevalence data and found that sleep bruxism affects approximately 13 percent of adults when assessed using self-report measures, with rates varying considerably across different populations ¹. Because many people are entirely unaware they grind their teeth, clinical rates identified by dentists examining tooth wear patterns tend to capture cases that patients would never self-report. This means bruxism is often a condition your dentist discovers before you do.

What Triggers It?

Current evidence points to several contributing factors. Psychological stress and anxiety are among the most consistently identified associations. Sleep-disordered breathing, including obstructive sleep apnea, has a well-established relationship with sleep bruxism ¹. Certain medications, particularly selective serotonin reuptake inhibitors (SSRIs), can increase bruxism activity as a side effect. Genetic predisposition also plays a role, as bruxism tends to run in families.

What an Occlusal Night Guard Does

An occlusal splint, commonly called a night guard, is a custom-fitted appliance worn over either the upper or lower teeth during sleep. Its primary function is to create a protective barrier between the upper and lower teeth, absorbing and redistributing the forces generated by grinding rather than allowing those forces to act directly on tooth structure ⁴.

Importantly, a night guard does not stop the bruxism itself. The clenching and grinding activity continues, but the appliance prevents the enamel-on-enamel contact that causes wear. Think of it as protective equipment rather than a cure.

Types of Night Guards

Not all night guards are the same. Soft, over-the-counter variants from pharmacies offer a low-cost entry point but are not recommended for long-term use in significant bruxism cases because their softness can actually increase muscle activity in some patients. Custom hard acrylic appliances, fabricated from impressions of your teeth by a dental laboratory, offer superior fit, durability, and therapeutic outcomes ⁵.

Research has also examined more targeted designs such as the NTI-tss, a small appliance that covers only the front teeth, and the Michigan splint, a full-arch hard acrylic device. A pilot study examining their short-term effects on nocturnal jaw muscle activity found that both reduced masseter muscle activity compared to baseline, but with individual variation in response ⁵.

What the Research Says

The evidence for night guards in managing the consequences of bruxism is substantial, though researchers are careful to distinguish between managing symptoms and eliminating the condition. A comparative study using surface electromyography found measurable reductions in masticatory muscle activity during splint wear ⁶, supporting the clinical rationale for their use.

A 2023 study in BMC Oral Health compared three different splint designs on patients with bruxism and found that all three produced improvements in neuromuscular indicators, though the magnitude of benefit differed by device type ⁴. This reinforces the importance of individualized selection rather than a one-size-fits-all approach.

There is also an important relationship between bruxism and temporomandibular joint disorders (TMD). A systematic review published in Evidence-based Dentistry confirmed a significant association between bruxism and TMD, with bruxism patients showing higher rates of joint pain and dysfunction ³. For patients presenting with both conditions, a night guard serves a dual protective function.

One nuance worth noting: a 2018 paper in the British Dental Journal raised the question of unintended occlusal changes from prolonged night guard use, particularly with softer appliances ². This underscores why periodic review by your dentist is part of appropriate night guard management, not just the initial fitting.

When to See Dr. Khalid

If you wake up with jaw stiffness or headaches, if your teeth feel sensitive without an obvious cause, or if someone has told you that you grind your teeth during sleep, these are meaningful signals worth discussing at your next appointment. During your examination, Dr. Khalid evaluates for signs of wear, occlusal stress, and TMJ involvement, and where a night guard is appropriate, takes precise impressions for a custom-fitted appliance. The goal, always, is to protect what you have.

Footnotes

Zieliński G et al. Global Prevalence of Sleep Bruxism and Awake Bruxism in Pediatric and Adult Populations. Journal of Clinical Medicine. 2024. doi:10.3390/jcm13144259 ↩ ↩² ↩³
Bereznicki T et al. Unintended changes to the occlusion following the provision of night guards. British Dental Journal. 2018. doi:10.1038/sj.bdj.2018.869 ↩ ↩²
Mortazavi N et al. Is bruxism associated with temporomandibular joint disorders? Evidence-based Dentistry. 2023. doi:10.1038/s41432-023-00911-6 ↩ ↩²
Lei Q et al. Neuromuscular and occlusion analysis to evaluate the efficacy of three splints on patients with bruxism. BMC Oral Health. 2023. doi:10.1186/s12903-023-03044-5 ↩ ↩²
Lukic N et al. Short-term effects of NTI-tss and Michigan splint on nocturnal jaw muscle activity: A pilot study. Clinical and Experimental Dental Research. 2021. doi:10.1002/cre2.371 ↩ ↩²
Lan KW et al. Comparative study of surface electromyography of masticatory muscles in patients with different types of bruxism. World Journal of Clinical Cases. 2022. doi:10.12998/wjcc.v10.i20.6876 ↩

COMMON QUESTIONS

What patients ask most.

How do I know if I grind my teeth?: Many people do not know until their dentist points it out during a routine examination. Signs your dentist looks for include flattened or worn biting surfaces, chipped enamel, scalloped edges on the tongue, and evidence of tooth sensitivity. You may also notice jaw soreness or headaches upon waking.
Will a night guard eliminate my jaw pain?: Night guards can significantly reduce muscle fatigue and joint strain by limiting the forces transmitted during grinding. Many patients report improvement in morning jaw pain and headaches. However, if significant temporomandibular joint dysfunction is present, additional treatment may be needed alongside the appliance [^4].
Can I buy a night guard at the pharmacy?: Over-the-counter guards are available but are not considered an adequate long-term solution for most cases of significant bruxism. They are less durable, fit less precisely, and some designs may inadvertently worsen muscle activity. A custom appliance made by your dentist is the clinically recommended option [^2].

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