Basic Concepts in Occlusion (2)

3. Commonly used terminology

a.  Occlusion (static): the contact between teeth of the opposing jaws at the end-point of the closure

b. Articulation (dynamic): the gliding contact during movements of the mandible

c.  Inter-cuspal Contact position (ICP): where the greatest number of contacts occur between the upper and lower jaws

d. Retruded Contact position (RCP): the most superior and posterior position of the mandible where the condyles cannot be retruded further.

e.  Freeway space: the space between the upper and lower teeth when the mandible is at rest.

f.   Occlusal Vertical Dimension (OVD): relationship between maxilla and mandible at ICP, i.e. face height

g.  Lateral excursion: sideways movements of the mandible with the teeth in contacts.

h. Anterior guidance: the palatal surface of the front teeth provide the guiding plane when the mandible slides forward (protrusion), separating the back teeth

i.    Canine guidance: the canine of the working side provide the guiding plane which separate the back teeth (disclusion) during lateral excursion, without any interference.

j.    Group function: teeth on the working side, with or without the canine, are in contact during lateral excursion. E.g.: premolars and molars, or, central and lateral incisors.

k. Premature contact: the first tooth contact when patient is closing onto the RCP.

l.    Interference: deflective contacts which prevent smooth movements to and fro from the ICP. It can be on the working side (the side to which the lower jaw is moving), non-Working side, or protrusive.

Reference information: www.bjdental.com/

It is not intended as medical advice to any specific person. If you have any need for personal advice or have any questions regarding your health, please consult your Dentist for diagnosis and treatment.