Send to

Choose Destination
J Chiropr Med. 2007 Dec;6(4):141-5. doi: 10.1016/j.jcme.2007.08.001.

The effect of cervical spine manual therapy on normal mouth opening in asymptomatic subjects.

Author information

Research Resident, Division of Research, Logan College of Chiropractic, St Louis, MO 63006.



Temporomandibular disorders are a group of disorders affecting the temporomandibular joint and/or masticatory muscles. One of the signs associated with temporomandibular disorders is a reduction in mouth opening. During normal mouth opening, extension occurs at the cervical-cranial junction. The purpose of this investigation was to determine if manual therapy applied to the cervical-cranial junction would significantly improve mouth-opening capacity.


One hundred one participants were randomly assigned to either an Active Release Technique (ART) group; high-velocity, low-amplitude manipulation (HVLA) group; or control group. A blinded investigator measured mouth opening using a TheraBite range of motion scale (TheraBite Corporation, West Chester, PA). Participants received ART to the suboccipitals or HVLA to the cervical spine at C1 or sat with an investigator for 3 minutes with no treatment. After the treatment session, mouth opening was remeasured. A repeated-measures analysis of variance was used to compare the group mean values. The a priori alpha level was .05.


The repeated-measures analysis of variance showed no significant difference between the ART, HVLA, and control groups' pretreatment and posttreatment measurements (F = 0.41, P > .05).


Manual therapy to the cervical spine did not significantly improve mouth opening in this asymptomatic population. Future trials using participants with restricted mouth-opening measures are warranted.

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center