Sudden Bite Change

• Clinical Definition: A patient develops an abnormal relationship between the upper and lower jaws in an unexpected manner.

• Red Flag Indicators: Cannot close the jaw, experiencing severe pain on one side of your face (preauricularly), localized swelling, or facial asymmetry. 

• Common Recovery Options: Occlusal stabilization therapy, selective occlusal adjustment, arthrocentesis/upper joint injection, manual reduction of the upper joint, and prosthetic/dental orthodontic alignment

Symptoms of acute malocclusion are very visible and can be felt as well as heard by patients: 

• Visual: The patient will see their upper and lower jaws do not fit together normally. 

• Tactile: Patients may feel like there is selective contact of the back molars with each other; therefore, they will never have contact with all of the molars on both sides of the top and bottom. The front of the mouth (incisors), including the central incisors and lateral incisors, will never meet either.

• Sensory: Patients may report that their jaw has deviated toward one side and they cannot open their mouth properly, accompanied by preauricular pain located immediately anterior to the tragus of the ear rather than directly behind it. Some describe this pain as sharp, some as dull. In addition to the pain in the preauricular region, some patients experience pain that radiates from the jaw down into their temples or even their necks. 

• Auditory: When the patient opens their mouth to talk or eat, it produces audible noises such as cracking, clicking, grinding or "popping" in the jaw joint (TMJ). 

• Facial Muscles Fatigue: After eating breakfast for example, a patient may feel fatigued in the muscles of mastication (masseter and temporalis muscles).

The following are red flag conditions that require a visit to your dentist/orthodontist immediately or to a local hospital's ER: 

• Lock Jaw: If you can barely open your mouth less than two finger widths apart. 

• Unusual Facial Swelling: Drooping in the corner of your mouth. Loss of sensation in your face/chin/lip. 

• Malocclusion Post-Trauma: Bites change after you hit your chin or face. 

• Fever & Throbbing Pain: Indication of an active infection such as a pericoronitis or periodontal abscess.

Acute malocclusions arise from a disruption in the local structural mechanics, musculature, or the overall functional system; these may include: 

• TMJ Articular Disk Displacement: When the articular disc is displaced anteriorly from its normal anatomical position without reduction, the mandibular condyle is physically blocked from translating forward, altering the normal path of motion. This can occur with an acute injury (trauma), chronic strain, or even due to systemic changes within the TMJ such as rheumatoid arthritis. Anterior disk displacement without reduction is defined as a non-reducible dislocation where the disk cannot be manually replaced into its proper anatomical position. 

• Acute Lateral Pterygoid Muscle Spasm: An abnormal hypercontraction or spasm of the lateral pterygoid muscle can abruptly alter mandibular positioning, frequently pulling the condyle forward and resulting in a sudden malocclusion or difficulty closing the mouth. This spasm can occur when patients are under undue stress while having their teeth cleaned for extended periods, causing them to unconsciously contract the muscles to prevent discomfort or pain. 

• Fractures: Fractures of the mandible or mandibular condyles resulting from blunt trauma either to the face or jaws. These fractures may result from motor vehicle accidents or sports injuries. 

• Dental Restorative Interference: High fillings, crowns, bridges or other restorations that cause interference to normal chewing and/or resting positions of the jaws. 

• Impacted Wisdom Teeth: Impacted wisdom teeth have caused the pericoronal tissue surrounding the impacted tooth to become inflamed and irritate adjacent teeth leading to defensive muscle guarding.

• Chronic Bruxism: Night time clenching and/or grinding has resulted in long term irritation and possible wear to the joint structures and the attachment sites of the masticatory muscles. 

• Systemic Joint Conditions: Arthritis (i.e., rheumatoid arthritis or osteoarthritis) causes degeneration of the condylar cartilage, resulting in reduced function of the TMJ. 

• Diet: Consuming many foods with very hard density (e.g. hard banana chips), fibrous density (e.g. un-refined sugarcane), or placing excessive lateral force on the TMJ (e.g. tough meat). 

• Anatomy: Deep bites, narrow dental arches, and hyper mobile joints.

You should perform the self-assessment in a manner that does not apply excessive pressure when you are checking for possible issues: 

• In a bright lighted area, view yourself in the mirror. Relax your face muscles. Close your upper lip slowly while keeping your bottom lip relaxed. Determine whether your facial midline is aligned with your chin. 

• First Contact Test: Gently bring your teeth into gentle contact without using extreme pressure. Make note of which tooth comes into contact with the opposing tooth first. If it is one single molar? 

• Range Of Movement: Open your mouth as far as possible. Place your fingers vertically from your front teeth, use two fingers. There will be restricted range of motion at both the horizontal and vertical planes. It may indicate that there is some degree of muscle guarding or disc blockage. 

• Palpation: Place an index finger in each ear. While slowly opening your mouth make sure there is no significant amount of pain present on either side. Also check for any type of bulge laterally on either side. Finally determine if there is unevenness in the range of motion from the right side compared to the left side. Do not attempt to move your jaw back into place if it has become stuck due to pain.

The combination of a thorough examination and appropriate diagnostic imaging provide for accurate diagnosis. 

• Occlusal Analysis: By using articulating paper (small thin strips with colored markings) or electronic occlusal sensors (such as T-Scan) to measure early contact points and distribution of bite forces. 

• Palpation And Range Testing: Evaluate tenderness of the lateral pterygoid muscle, evaluate the mobility of the condyle and measure the distance from one incisor to another during maximum opening. 

• Radiology: 

  • Panoramic Radiograph (OPG): A panoramic radiograph can help identify large bony fractures or severe degeneration within the lower jaw and mandible and can also assess the condition of the TMJ (temporo-mandibular joint).

  • Cone Beam Computed Tomography (CBCT): CBCT uses x-rays to create three-dimensional images of the bones of the jaw and TMJ.

  • Magnetic Resonance Imaging (MRI): MRI provides high-quality images of the soft tissue cartilage disc, joint fluid collection and torn muscles.

Acute bite changes are categorized based on structural involvement and functional impairment:

The goal of management is to treat the root structural problem utilizing current methodologies: 

• Occlusal Stabilization Therapy: Customized 3-D printed occlusal stabilization splints (Michigan splints) which reduce the mechanical load of the joint and relieve spasms of the lateral pterygoids; allow the mandible to be guided into centric relation. 

• Selective Occlusal Adjustment: Using diamond burs and microscopic examination, micro-adjustments to high points on restorations or crowns to establish a balance in occlusion. 

• Arthrocentesis/Upper Joint Injection: Removal of pro-inflammatory substances from the TMJ upper joint space through arthrocentesis under local anesthetic; often followed by injection of hyaluronic acid or platelet-rich plasma to provide comfort to injured tissues. 

• Manual Reduction of the Upper Joint: Re-establishment of normal position of the upper joint by a trained provider. 

• Prosthetic/Dental Orthodontic Alignment: Re-alignment over time using clear aligners or full mouth crowns after the acute pain/inflammation has resolved.

Treatment costs varies based upon location and the type of condition (muscular, dental, structural):

Insurance Coverage: Outpatient basic dental care is primarily self-funded, but hospitalizations for traumatic jaw fractures/open TMJ surgery will be covered under most medical insurance policies/state health programs within participating hospitals.

• General Dentist: Initial evaluation and primary screening of acute occlusal shifts. 

• Prosthodontists: Complex occlusal restorations and balancing following stabilization. 

• Oral And Maxillofacial Surgeons: Management of severe skeletal fractures, trauma, and joint surgeries. 

• Orofacial Pain/TMJ Specialists: Treatment of acute muscular spasms and internal joint derangements.

• Urgent (Within 2-4 Hours): Inability to close or open the mouth, severe trauma-induced malocclusion, or locked jaw. 

• High Priority (Within 24-48 Hours): Sudden bite changes following a recent dental filling or crown insertion causing severe pain. 

• Elective (Within 1-2 Weeks): Mild intermittent bite discrepancies without locking or acute pain.

1. Can a rapid bite change self-correct? 

While some changes may correct themselves if caused by temporary muscular strain, others will not. The latter include those that result from joint disc dislocation and/or structural changes in the masticatory system. A professional assessment is needed so as to avoid TMJ permanent injury.

2. Should I try to push my teeth together to reset my bite? 

No. Pushing your teeth together with resistance may cause tooth fractures, exacerbate muscular spasm, and/or tears to the cartilaginous disc within your temporomandibular joint.

3. Why did my bite feel differently after receiving an ordinary dental restoration (filling)? 

A high dental restoration measuring even a fraction of a millimeter can create premature occlusal contact, triggering protective muscle reflexes and altering the natural resting position of the jaw. This alteration may induce muscle guarding which would limit your ability for your back teeth to meet properly.

•  Temporomandibular Joint Disorders (TMD): Long-standing chronic inflammation and/or internal derangement of the TMJ. 

• Condylar Hyperplasia: An abnormal unilateral growth of the condyle of the mandible causing a progressive deviation of the occlusal plane. 

• Cervical Spine Dysfunction: Postural asymmetry in cervical spine function alters the resting position of the hyoid bone and the lower jaw.

• Ultrasound & Physical Therapy: The goal of this treatment option would be to improve flexibility of the lateral pterygoid muscle and decrease inflammation in the joint capsule (capsulitis). 

• Botulinum Toxin Injections: A targeted approach to relax hyperactive muscles within the masseter muscle group in order to alleviate severe muscle spasm. 

• Orthodontic Treatment: Orthodontic treatment could include clear aligners for long term stabilization of a post-treatment occlusal relationship or traditional fixed appliances.

The immediate shift from one occlusal dynamic to another represents a disruption in the natural balance among the maxillary and mandibular dental arches, masticatory musculature and TMJ's. Thus it is imperative that early intervention take place so as to prevent secondary issues such as localized enamel attrition, localized periodontal overloading and chronic myofascial pain. Additionally, patients are encouraged not to attempt their own manipulation of the jaw, consume a soft diet and have a complete clinical evaluation performed with diagnostic imaging, and occlusal verification. Ultimately, long term success will depend upon achieving consistent and stable positioning of the joints prior to initiating final restorative dental/bite work.