Central occlusion is a form of articulation, in which the muscles lifting the lower jaw are uniformly and maximally strained on both sides. Because of this, when the jaws are joined, a maximum number of points contact each other, which provokes the formation of an incorrect occlusion . The articular heads are always at the very base of the calf slope.
Signs of central occlusion
The main signs of central occlusion are:
- each lower and upper tooth densely closes with the opposite to it (except for the central lower incisors and the three upper molars);
- in the frontal part, absolutely all of the lower teeth overlap the upper teeth by not more than 1/3 of the crown;
- the right upper molar connects with the lower two teeth, covering them by 2/3;
- the incisors of the lower jaw tightly contact the palatal tubercles of the upper jaw;
- the buccal hillocks located on the lower jaw are overlapped by the upper;
- The palatal tubercles of the lower jaw are located between the lingual and buccal;
- Between the lower and upper incisors the middle line is always in the same plane.
Definition of central occlusion
There are several methods for determining the central occlusion:
- Functional technique - the patient's head tilts back, the doctor puts the index fingers on the teeth of the lower jaw and places special corners in the corners of the mouth. The patient lifts the tip of the tongue, touches the palate and swallows at the same time. When the mouth closes, you can see how the dentition closes.
- Instrumental technique - provides for the use of a device that records the movements of the jaws in the horizontal plane. When determining the central occlusion with a partial absence of teeth, the lower jaw is forcibly displaced by hand, pressing on the chin.
- Anatomical and physiological technique - determination of the state at physiological rest of jaws.