Primary TrPs in the SCM often cause secondary TrPs that invoke dental pain. People with SCM TrPs often have trouble glancing downward they can become so disoriented that nausea and vomiting result. Chronic dry cough, pain deep in the ear canal, pain to the throat and back of the tongue and to a small round area at the tip of the chin can be part of the SCM TrP package. These TrPs can also cause pain at the mastoid process and the deep nuchal line. This is a nighttime sinus stuffiness occurring on one side of the head which moves to whichever side of the head is lower.
Gravity drains the congestion to the lower side.
This condition accompanies postnasal drip and a constantly runny nose. Trigger points can form from this irritation, which eventually may refer teeth pain. I think that with muscle tightening, normal fluid passages are constricted, and fluid backs up in the sinuses. So we get a constant postnasal drip all night, although the membranes of the nose may feel very dry and even bleed. This sensation is frequently experienced upon waking in the morning or during times of intense stress.