Onset, natural course and risk factors of temporomandibular joint internal derangements in children

Clicking of the temporomandibular joint (TMJ) is one of the typical clinical
manifestations of internal derangements (IDs) of the TMJ. The two main types of
IDs are disc displacements (mostly in anterior direction) and hypermobility.
IDs are, in general, not a source of complaints, and are therefore not treated,
except in cases when joint locking or pain occurs. A number of studies,
focusing on TMJ clicking in general, have found an increasing prevalence in
children and adolescents, but have also described clicking as intermittent and
episodic. However, these studies did not make a distinction between the two
forms of IDs. Therefore, the genesis and natural course of anterior disc
displacement, and of TMJ hypermobility in children, is unknown. This is also
true for the risk factors for development of IDs, as well as for the factors
related to a possible discontinuation of ID's in time.

To investigate the onset and short term natural course of ADD and TMJ
hypermobility in children, and to give insight into some related risk factors.

A longitudinal observational cohort study.

This study is observational and carries no risk towards the participant's
health. The minimal burden for the participants is paying several half-year
visits, coupled with the regular dental check-ups at ACTA. At each visit the
participants will be shortly examined clinically in relation to joint sounds,
and a short questionnaire will be done. The participants with IDs will
additionally undergo mandibular movement recordings.

By participating, the subjects benefit from the diagnostic procedures and
explanation about the phenomenon *clicking joint*. In case joint locking or
pain arises throughout the study, as part of the natural course of the
condition, treatment will be initiated with priority. This research is regarded
as group related, because an indication exists that the activity of ID-related
factors in this age group is greatest.