assessing a new jaw support device during third molar extractions

Conditions: Impacted Third Molar Tooth; Temporomandibular Disorder

Summary: during mandibular 3rd molar (wisdom tooth) extractions, when a downward force is placed on the patient's jaw, the patient must tense his/her jaw muscles to oppose it. patients under moderate/deep sedation or general anesthesia cannot tense their muscles to counter this downward force to prevent injury to the jaw including the temporomandibular joint (tmj). bite blocks hold the patient's mouth open but do not counter this downward force on the mandible. currently, oral and maxillofacial surgeons (omss) when surgically removing 3rd molars (wisdom teeth) with moderate/deep sedation or general anesthesia have a dental assistant that stands behind the chair and places their hands on both sides of the jaw to support it and oppose the downward force on the patient's jaw during the extractions. it is hard for the dental assistant to maintain support while anticipating the direction and amount of force placed by the oms on the patient's jaw during the surgical removal. this may explain the finding that almost a quarter of new onset tmd cases in young adults is associated with 3rd molar removal. this study will look at the use of a jaw support device to provide a stable counterforce to downward forces on the jaw, thus preventing jaw hyperextension and injury to the jaw.

dental procedures can cause jaw pain, discomfort and fatigue from opening the mouth too long or too wide, or by placing too much force on the jaw. (1-15) opening too wide can also cause hyperextension of the jaw. during and after long dental procedures, patients frequently report jaw pain, fatigue, or discomfort. this pain and dysfunction characterizes temporomandibular disorders (tmd), which can be short-term or may become chronic. tmd occurrence is frequently associated with trauma from dental procedures, including 3rd molar extractions. (1-15) also, dental procedures may aggravate pre-existing subclinical tmd symptoms. (16) when a downward force is placed on the patient's jaw to surgically remove the mandibular (lower) 3rd molars, the patient must tense his/her jaw muscles to oppose it. this can result in jaw pain, discomfort or fatigue, especially if the force is high or prolonged. patients under moderate/deep sedation or general anesthesia cannot tense their muscles to counter this downward force to prevent injury to the jaw. bite blocks hold the patient's mouth open but do nothing to counter this downward force on the jaw. opening a patient's mouth too wide can cause jaw hyperextension; a long extraction procedure time can also lead to injury of the jaw. currently, oral and maxillofacial surgeons (omss) when surgically removing 3rd molars (wisdom teeth) with moderate/deep sedation or general anesthesia have at least 2 dental assistants present. the first dental assistant provides suction and gives the surgical instruments to the surgeon. the second dental assistant is a certified anesthesia dental assistant who monitors the patient's vitals as well as oxygen and carbon dioxide levels while providing the patient with medications intravenously. this second dental assistant also inserts the bite block and then stands behind the chair and places their hands on both sides of the jaw to support it and oppose the downward force on the patient's jaw during the extractions. if additional intravenous medications are needed during the surgery, the surgery has to stop (lost time) and the oms or the first dental assistant supports the jaw until the second dental assistant completes the medication administration. based on clinical experience, the second dental assistant often experiences fatigue and pain in their hands, arms, neck and shoulders during long or difficult procedures, which can affect his/her ability to support the jaw. given the second dental assistant's many duties and responsibilities, it is hard for the assistant to provide constant good jaw support while anticipating the direction and amount of force placed by the oms on the patient's jaw during 3rd molar surgical removal. this may explain the finding that almost a quarter of new onset of tmd cases in young adults is associated with 3rd molar removal. this patient safety issue can be addressed during 3rd molar surgical removal by using a bite block to hold the mouth open and concurrently using a jaw support device under the jaw to provide a stable counter force to downward forces on the jaw, thus preventing jaw hyperextension and injury to the jaw. this would also free the second dental assistant from holding the jaw so he/she can concentrate on his/her other duties, which would improve patient safety. in this two-arm parallel randomized clinical trial design, 294 patients undergoing 3rd molar extractions with moderate/deep sedation or general anesthesia will be randomly allocated to usual care (uc) or experimental care (ec). patients presenting for surgical removal of 3rd molars will be invited to participate in the study at the time of their oral surgery consult. the oms will determine if the patient meets eligibility criteria, explain the study and invite them to participate. at the time of 3rd molar removal, the oms and their dental assistants will follow their standard procedures for obtaining consent from patients for 3rd molar removal with moderate/deep sedation. in addition, they will confirm the patient's interest to participate in the study, ask if they have any questions an obtain consent. the jaw device will be placed for those who are randomized into the ec group. the oms will follow their standard protocol for removal of the teeth. the only change will be that the dental assistant standing behind the chair will be present at all time to readjust the device position as needed or remove the device as indicated. the default in the case of device malfunction is for the device to fall away from the patient and the dental assistant will be immediately available to take over supporting the patient's jaw with their hands, which is one of their standard responsibilities when the device is not used. patients will report temporomandibular disorders (tmd) pain via questionnaires at baseline and at the 1-, 3-, and 6-month follow-up time points via email, phone and/or text.

Eligibility criteria:
inclusion criteria: * between 18 to 30 years of age at time of enrollment; * willing to provide informed consent to be randomized to either using the device or not when having surgical removal of 3rd molars with moderate/deep sedation or general anesthesia; * requires surgical removal of bilateral mandibular 3rd molars with moderate/deep sedation or general anesthesia; concurrent maxillary 3rd molars removal allowed; * american society of anesthesiologists (asa) physical status category 1 (normal healthy patient) or category 2 (patient with mild systemic disease); * available to be contacted for study purposes by e-mail, phone and/or text; * willing to provide contact information for one other person who will know the patient's whereabouts in the event the patient cannot be reached. this contact information must be different from the patient's contact information; * willing to comply with all study procedures and be available for the six month duration of data collection. exclusion criteria: * in the past 3 months, reports the presence of tmd pain in their temples, jaw joints or jaw muscles; * contraindication(s) for moderate/deep sedation or general anesthesia; * any condition or situation the surgeon determines that would prevent the patient from participating in this study; * inability to understand study procedures or provide consent in english; * device does not fit mandible; * supernumerary 3rd molars present.

Keywords: jaw support device wisdom teeth impacted temporomandibular disorders