July 11, 2016
by Brad Eli, DMD, MS; James Fricton DDS, MS
One of the most common non-infectious complications resulting from dental care is jaw joint and muscle strain/sprain. Jaw joint and muscle strain/sprain are characterized by acute joint pain, limited range of motion, muscle tenderness, and muscle and joint dysfunction. If left untreated, these can progress into a chronic condition. This article presents a treatment technique for effectively managing 1st and 2nd degree jaw strain/sprain injuries and presents two cases demonstrating its use.
Jaw Joint and Muscle Strain/Sprain: A Common Complication from Dental Care
Jaw joint and muscle strain/sprain can occur after lengthy dental procedures requiring opening the mouth wide or from forces placed on the jaw during dental care. Procedures such as mandibular blocks, crown preparation, dental extractions, periodontal, endodontic, etc., can cause jaw joint and muscle strain/sprain. Additionally, finger rests can place forces on the jaw and cause hyperextension of the joint and strain of the muscles. Acute jaw joint and muscle sprain/strain after dental procedures is more common than originally thought with more than 50% of patients with temporomandibular disorders (TMD) reporting their pain onset as a direct result of dental care.1-13 In one study of 164 patients with TMD, trauma was the initiating factor in 50.6% of cases, with 61% of these cases coming from trauma and strain during dental treatment.7 Among young adults, 23% of all jaw pain cases had their onset after third-molar extractions.8-9 Other causes of jaw trauma include motor vehicle accidents, intubation during general anesthesia, yawning, blows to the jaw, or hard and sustained chewing.10-13
Early Treatment Can Prevent Progression to a Chronic Condition
When a jaw joint and muscle strain/sprain does occur, it is important to take appropriate early steps to encourage rapid healing to resolve pain and mitigate any risk factors that can delay recovery. These steps must include adequate treatment of the injury and reduction of complicating risk factors, such as parafunction, muscle bracing, and jaw overuse. Failure to provide prompt treatment can result in a progression to a chronic pain condition.
If pain is untreated, peripheral and central sensitization occurs due to the neuroplasticity of the nervous system and recruitment of agonist muscles.14 Local tissues become more tender and sensitive to mechanical stimulation. As the pain progresses to chronic, additional signs of sensitization including allodynia (sensitivity to normal touch) and hyperalgesia (more pain with normal stimulation) may develop. Initial symptoms can increase to include headaches, earaches, neck pain and jaw dysfunction such as clicking and locking. Since oral and facial structures are essential to eating, communication, and hearing, and strongly influence appearance, self-esteem, and personal expression, chronic orofacial pain can affect quality of life, functioning, emotional status, and dental care.
Treatment of Jaw Strain/Sprain
Acute sprain/strains can occur at any joint and muscle group. Sprain/strains can vary from 1st degree (slight muscle or ligamentous tear with mild pain and functional limitation) to 2nd degree (partial muscle or ligament tear with blood clot formation, moderate pain, and functional impairment) and 3rd degree (total separation of the muscle or ligament with severe pain, loss of function and stability). Signs and symptoms of each include progressively increasing pain, tenderness, swelling, limited range of motion, and functional loss (Fig. 1).
To encourage rapid healing of sprain/strain injuries in 1st- and 2nd-degree injuries, a MEAT Protocol including movement, exercise, analgesia, and treatment is recommended. The treatment of a 3rd-degree injury requires a RICE protocol including rest, ice, compression, and elevation. This article provides a reliable and effective MEAT protocol for treating 1st and 2nd degree injuries commonly seen in a dental practice.
As part of this protocol for jaw injury, an interim anterior bite splint (night-time wear) should be used to support, relax, and protect the jaw joints and muscles, similar to how an elastic bandage supports and protects a wrist or ankle injury. Additionally, jaw exercises are prescribed to restore normal function and range of motion.
Jaw Joint and Muscle Strain/Sprain Treatment Technique
This is a simple and effective treatment technique for patients who experience acute jaw pain after procedures. Much as in orthopedics, prompt treatment, preferably on the same day, improves success in reducing pain and dysfunction at the acute stage. Failure to provide treatment promptly can directly effect the outcome.
The four steps of the MEAT approach for 1st and 2nd degree jaw injuries include:
1. Movement. This includes self-care training in the proper use of the jaw and avoiding risk factors that can delay recovery. With 1st or 2nd degree injuries, a MEAT protocol and careful use of the jaw increases blood flow, encourages healing, and restores jaw function. Risk factors such as parafunction, muscle bracing, and jaw overuse should be avoided.
2. Exercises. Restoration of normal function can be achieved with exercises that focus on stretching to restore normal range of motion. In addition, posture and relaxation exercises reduce strain to the muscles and encourage healing. Patient jaw exercise instructions are available in notepad form for distribution (Jaw-Rx-ercises, QuickSplint LLC). Patients with chronic baseline conditions may also find self-help on-line training programs such as the International MYOPAIN Society (www.preventingchronicpain.org).
3. Analgesia. For pain relief, acetaminophen, anti-inflammatories, topical, or hydrotherapy (alternating heat and cold) reduce pain and facilitate movement, exercise, and healing. For more intense pain, the Center for Disease Control has developed opioid prescribing guidelines and provides a comprehensive user guide. Failure to provide adequate pain control can limit the patients’ willingness to move and can have a negative effect on outcome.
4. Treatment. The QuickSplint (QuickSplint LLC) is an immediate anterior bite splint that can be placed on the same day at chairside to help protect the jaw and is similar to a protective elastic bandage for ankle and wrist injuries. The splint, worn at night, can reduce jaw closing muscle activity (e.g., jaw clenching or tooth grinding), inhibits the maximum bite force, and helps to encourage healing of acute temporomandibular pain and related restricted jaw opening. The flat occlusal surface allows the mandible to move freely instead of closing into a specific dental relationship, and encourages healing and normal function. The advantages over traditional lab-manufactured splints include; 1) immediate placement (no impression), 2) custom fit, 3) large enough to avoid aspiration or swallowing, and 4) temporary (up to four weeks) to minimize occlusal changes and allow time to place a long-term splint (Fig. 2).
FIGURES 2-5. QuickSplint is an immediate anterior bite splint that can be placed immediately at chairside to help protect the jaw and is similar to a protective elastic bandage commonly used for an ankle or wrist injury. QuickSplint is an immediate anterior bite splint that can be placed immediately at chairside to help protect the jaw and is similar to a protective elastic bandage commonly used for an ankle or wrist injury.
Case Study: Jaw Muscle Strain After Crown Preparation
History of Present Illness:
A 62-year-old female with no prior signs of parafunction, jaw symptoms or other health conditions presented a one-week history of sudden onset pain after crown preparation and placement on tooth 37. At onset, the patient was given a soft mouth guard. It was unsuccessful in treating her pain. The patient avoided chewing on her left side. Due to increased jaw dysfunction and her failure to improve after using a “soft splint,” she was referred to an orofacial facial pain (OFP) specialist.
Clinical Examination by the OFP Specialist
Limited jaw opening measured 10 mm without pain extending to 28 mm with pain. Left jaw pain and headache; recent onset left eye and ear pain as well. Protrusive movements were within normal limits.
1. Sprain and strain, left temporomandibular joint and associated muscles.
2. Possible disc displacement without reduction
3. R/O temporal arteritis
Given the age of the patient, the risk of temporal arteritis is of concern. Sed rate would be indicated and was discussed with the patient, however, with the known onset and other differential diagnosis present, this blood test was placed on hold but informed consent was discussed. Regarding the possible disc displacement and possible “closed lock” based on the protrusive range, muscle guarding was thought likely and confirmed with spray and stretch that demonstrated 45 mm of opening.
The primary diagnosis for treatment was sprain/strain of the medial pterygoid with likely post injection injury to the muscle. The patient was given an anterior overnight bite splint and educated on self-care measures that included jaw exercises for daytime use (MEAT protocol).
Results and Follow-Up
The patient was seen two weeks later and reported a significant improvement. Due to prompt treatment and negative prior history, this patient demonstrated the orthopedic nature of the temporomandibular joint complex and its healing abilities. The condition resolved at the four-week follow-up. The patient confirmed that interim splint and the jaw exercises were helpful in resolving her condition.
At four weeks, wear marks consistent with significant parafunction were noted on the surface of the QuickSplint interim splint. This finding supports the lack of response to the original soft device. Use of soft “night guards” in the presence of significant parafunction is not recommended as it can aggravate the behavior in some patients. With this finding the patient was advised that she would benefit from tooth structure protection in the form of a hard, flat plane, full arch device with cuspid guidance.
Case Study Two: Pain After Bilateral Root Planing and Scaling Procedure
History of Present Illness
A 67-year-old male had bilateral scaling and root planning with anesthesia. During the two one-hour sessions, one-week apart, the patient’s jaw was open most of the time. One week following the second procedure, the patient experienced a sudden onset of pain with limited jaw opening.
Medical history was negative for risk factors; no prior history of TMJ problems or facial muscle pain. He was seen by the treating dentist who recorded a 22 mm painful jaw opening. No “pre-treatment” jaw range of motion (ROM) was recorded.
Due to his sudden onset of pain and significant limitation of mobility, the patient was provided anti-inflammatory and pain medication along with a referral to an orofacial pain specialist.
Clinical Examination by the OFP Specialist
Two weeks from onset, the OFP examination was significant for limited ROM and pain. Maximum range of motion 24 mm with a hard end feel. No risks on medical history for muscle problems and no prior history of TMJ issues.
Internal derangement bilateral TMJ without reduction (closed lock). Muscle splinting/guarding medial pterygoid bilaterally.
The patient was advised to wear the QuickSplint interim splint at night and part of the day. He was given daytime avoidance exercises (Jaw Rx-ercises) limited to pain-free range and alternating hot/cold pack for 30 minutes/day while watching TV or reading to improve blood flow. Hot and cold drinks were also recommended for better access to the medial pterygoid.
Results and Follow-Up
At four weeks from onset, the patient’s muscle spasm had resolved. Jaw opening measured 45 mm without pain; the patient was advised to hold back on full jaw function for an additional two weeks. Due to prompt treatment and negative prior history, the patient demonstrated the orthopedic nature of the temporomandibular joint complex and its healing abilities.
Jaw joint and muscle sprain/strain are common complications from dental care. The two cases are characteristic of common events. Prompt treatment, preferably on the same day, improves success in reducing pain and dysfunction at the acute stage, and, even more importantly, helps to prevent chronic pain. Failure to identify and treat jaw joint and muscle sprain/strain immediately can have a significant negative impact on prognosis, regardless of diagnostic prowess or expertise, and everything to do with the CNS and its response to unremitting pain. Within the dental profession, there are few clinical techniques related to treatment of jaw joint and muscle sprain/strain, and even less recognition of the prevalence of injuries, patient risk factors, and associated preventative measures. Treatment technique is improving due to the growing number of practitioners and researchers in orofacial pain. The treatment technique outlined in this article is designed to assist dentists in reliably providing conservative and appropriate care if a jaw injury occurs. OH
Bradley Eli, DMD, MS is a Board Certified Specialist in orofacial pain, TMD and related headaches. He developed the jaw joint and muscle strain/sprain treatment protocol and the QuickSplint for his own practice to treat patients suffering with acute jaw joint and muscle sprain/strain.
James Fricton, DDS, MS is Professor Emeritus, University of Minnesota Schools of Dentistry, Medicine, and Public Health, Senior Investigator for HealthPartners Institute for Education and Research, and Pain Specialist at the Minnesota Head and Neck Pain Clinic. He is the President of the International Myopain Society.
Disclosure: Orofacial pain specialist, Dr. Bradley Eli, is founder of QuickSplint LLC and has a financial interest in a product mentioned in this article.
Oral Health welcomes this original article.
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