Why Do My Molars Hurt When I Bite Down? Explained by Dentist

That sharp, sudden twinge when you bite into a sugary treat or a crisp apple might not be a temporary thing. When your molars hurt when biting down, it’s usually a sign of a serious underlying problem.

At Lynnwood Dental Studio, we believe that understanding the reasons for a sudden or unexpected dental pain is the first step toward finding the right treatment. In this guide, our expert team lists down the most common reasons for molar pain during biting and why you shouldn't ignore it.

Why Are Molars Sensitive to Pressure?

Molars are the hardest workers in your mouth. They can withstand incredible pressure, up to 200 pounds to be exact, to ensure proper grinding of food. But even they are susceptible to considerable damage, particularly to their roots and soft tissues.

When you bite down, you are applying pressure not just to the molars but also to the periodontal ligament, a tissue that holds the tooth and bears the shock to protect the jawbone. If the tooth or the ligament is damaged, the biting pressure directly leads to sudden pain.

Common Culprits: Why Your Molars Hurt When You Bite Down

Our experts list some of the most common reasons for pain when biting.

Cracked Tooth Syndrome

This is one of the most common causes of pain during biting. Unlike a cavity, which causes consistent pain, a crack often hurts only when you bite. This is because when you bite, the crack gets wider, and when you release the pressure, it snaps back together. The process irritates the internal pulp (the nerve), leading to sharp pain.

Solution: Depending on the crack level and condition, your dentist may recommend a dental crown treatment to hold the tooth together or a root canal if the crack is too deep.

Dental Abscess or Infection

If you feel throbbing pain or if there is also a small bump on the gums, this is often the sign of a tooth infection. When infected, every bite pushes the tooth into a pocket of pus and inflammation, causing excruciating pain. Left untreated, tooth infection can spread to the jawbone or even to other body parts.

Solution: The dentist may recommend an emergency root canal or, in severe cases, an extraction.

Pulpitis (Inflamed Nerve)

The pulp is where nerves and blood vessels reside within the tooth. If a deep cavity or concussion has damaged the pulp, it can become inflamed.

Solution: If the nerve is irritated but reversible, the dentist will try to save it with a simple filling. If the damage is too great, a more intensive treatment might be needed.

High Fillings or Restorations

If you had a filling or a crown placed recently, which is even slightly too high, it might put excessive force on the opposing tooth during biting, bruising the periodontal ligament.

Solution: Early detection ensures a quick, painless adjustment, where the high spot is trimmed to even out your bite.

Other, Less Common Causes of Molar Pain

Sometimes, the problem is not the truth, but the surrounding environment.

Periodontal (Gum) Disease

When gum disease advances to periodontitis, the bone and tissues supporting the tooth may begin to dissolve, causing the molar to be slightly mobile. Constant bites can cause the tooth to shift in its socket, leading to a sharp, concentrated ache.

Sinus Congestion or Infection

With your upper molars located directly beneath your maxillary sinuses, any inflammation or infection of the sinuses due to allergies or a cold can result in extra pressure on the roots of your teeth.

Bruxism (Teeth Grinding)

If you wake up with aching molars or a light headache, it’s likely the sign of a grinding habit. Constant grinding wears the ligaments and can damage the enamel over time, making your teeth hypersensitive to the biting pressure.

Determining the Cause by the Type of Pain

Understanding the type of pain can help you determine the possible cause.

Pain Type	Likely Cause	Urgency
Sharp pain on bite release	Cracked Tooth Syndrome	High
Dull, constant pain	Abscess or Deep Cavity	Emergency
Ache in multiple upper molars	Sinus Pressure	Low
Sensitivity to cold/sugar	Receding Gums or Enamel Erosion	Moderate
Pain after a new filling	High Bite (Occlusion)	Moderate
Aching molars in the morning	Teeth Grinding	Moderate

What Happens If You Ignore the Pain?

Many patients think that if they just leave the aching tooth alone, it will heal on its own. Unfortunately, dental issues almost always worsen over time.

A small crack that could have been repaired with a simple filling can spread to the nerve, creating the need for a root canal. If the crack extends below the gum line, it might be impossible to save the tooth.

Professional Diagnosis and Treatment at Lynnwood Dental Studio

If you’re experiencing biting pain, we recommend visiting your dentist at the earliest. We at Lynnwood Dental Studio use advanced diagnostic tools and methods, including Digital X-rays, Bite Tests, and 3D CBCT Imaging, to determine the exact cause of pain before applying the best possible treatment.

Preventive Measures: How to Avoid Molar Pain

Prevention is the best cure. Here are some ways to protect your molars and avoid the risk of biting pain:

• Wear a Nightguard: If you grind your teeth at night, a custom-fitted nightguard can protect your molars from cracking.

• Avoid chewing on ice or hard candies.

• Replace Old Metal Fillings: Over the decades, metal fillings can expand and shrink, causing the tooth to crack.

Conclusion: Don't Ignore Molar Pain

Pain when biting down is often a sign of a compromised molar structure or an underlying disease. Whether it is a minor, occasional discomfort or a persistent issue, taking action early can be the difference between a quick fix and a complex, expensive procedure.

At Lynnwood Dental Studio, we prioritize your comfort and provide the best recommendations to protect your natural smile. Contact us today to talk to a professional dentist.