Anxiety or Panic Disorder: Intermittent jaw and chest tightness lasting for seconds to minutes can be associated with anxiety or panic attacks. These conditions often present with episodic symptoms that can include chest discomfort, jaw tension, and other somatic complaints.

Gastroesophageal Reflux Disease (GERD): GERD can cause chest tightness or discomfort, and in some cases, jaw pain due to referred pain from the esophagus. Symptoms can be intermittent and triggered by certain foods or positions.
Costochondritis: This condition involves inflammation of the cartilage that connects the ribs to the breastbone, leading to chest pain and possibly referred pain to the jaw. The pain can be sharp and intermittent.
Temporomandibular Joint (TMJ) Disorder: TMJ disorders can cause jaw pain and tightness, which may radiate to the chest or be perceived as chest tightness due to the complex innervation of the face and chest.

Acute Coronary Syndrome (ACS): Although less likely given the short duration and intermittent nature of the symptoms, ACS (including myocardial infarction) must be considered, especially in patients with risk factors. Chest pain or discomfort is a key symptom, and jaw pain can be a referred symptom.
Pulmonary Embolism: Sudden onset of chest tightness or pain, even if intermittent, could be indicative of a pulmonary embolism, especially if accompanied by other symptoms like shortness of breath or syncope.
Aortic Dissection: This is a life-threatening condition that can present with sudden, severe chest pain that may radiate to the jaw or back. Although the pain is typically constant, any severe or unusual chest pain warrants immediate investigation.

Hypertrophic Cardiomyopathy: A condition where the heart muscle becomes thickened, which can lead to chest pain, shortness of breath, and in rare cases, jaw pain due to abnormal heart rhythms or outflow obstruction.
Esophageal Spasm: Abnormal contractions of the esophagus can cause chest pain that may be confused with cardiac issues and could potentially radiate to the jaw.
Mitral Valve Prolapse: A condition where the two valve flaps of the mitral valve do not close smoothly or evenly, which can lead to chest discomfort, palpitations, and in some cases, jaw pain due to autonomic nervous system responses.