Wednesday, January 10, 2024

The most prevalent primary molar relationship.. flush terminal plane

The most prevalent primary molar relationship:

  • a- flush terminal plane.
  • b- mesial step terminal plane.
  • c- end.
  • d- distal.

The most prevalent primary molar relationship is actually: a. flush terminal plane.

This means that when the jaws are closed in a biting position, the mesial (front) surface of the second primary molar sits flush against the distal (back) surface of the first primary molar.
Here's how the other options compare:

b. mesial step terminal plane:

In this case, the second primary molar would be slightly forward (mesially) compared to the first primary molar, with its mesial surface overlapping the distal surface of the first molar by a small amount.

c. end:

This term isn't typically used to describe molar relationships. It might be referring to a specific type of occlusion where the molars don't actually touch at all.

d. distal:

This would mean the second primary molar is positioned behind (distally) the first primary molar, with a gap between their distal surfaces.

Studies have shown that the flush terminal plane relationship is the most common, found in around 68% to 80% of children with primary dentition.

Additional Factors:

Here are some additional factors that can influence primary molar relationships:


As children grow, their jaws develop and the primary molars may shift slightly in position.

- Genetics:

Some individuals are naturally predisposed to certain molar relationships.

- Oral habits:

Habits like thumb sucking or tongue thrusting can affect the position of the teeth.

It's important to note that the primary molar relationship is not necessarily predictive of the permanent molar relationship. However, observing the primary molar relationship can be helpful for dentists in planning future orthodontic treatment, if necessary.