Chapter 9 A New Way to Assess the Harmony of Dentition Occlusion

Here we present a way of diagnosing dental anomalies which, in our opinion, makes it possible to improve the quality of diagnosis.

In addition to gnathic abnormalities, dentofacial anomalies are also known to affect facial aesthetics and the function of the dentofacial system itself.

It is very difficult to determine the «place» of occlusion, its location and how the occlusal plane is formed, and its direction.

It affects the type of occlusion of the dentitions, facial aesthetics (appearance of a gingival smile), and most importantly, functioning of the TMJ, the muscles of the maxillofa-cial region, and the periodontium of the teeth.

What Prompted the New Method?

Incompleteness of obtaining cephalometric parameters in head TRG analysis.

Neither method provides the ability to determine the location of the dentition and occlusion in the TRG analysis.

The degree of severity of the anomaly, which must be assessed in the sagittal, vertical, and transversal directions, is not taken into account. The mesiodistal dimensions of the teeth are not taken into account. It is known that the larger the size of the teeth, the larger the size of the dentitions.

Hence, the point of incisor occlusion is located differently. It changes the position of the teeth and changes the aesthetics of the face.

To assess the occlusion of the upper and lower incisors, it was proposed to consider the Po-N line (Fig. 9.1) and the Po-N-I angular parameter (Fig. 9.2) as a reference line.

Fig. 9.1. Po-N reference line

Fig. 9.2. Assessing the incisor occlusion by the Po-N-I angle

To assess the occlusion of the upper and lower first molars, the Po - N - M angle is considered (Fig. 9.3).

Then the direction of the occlusion line through the occlusion point of the incisors I and the occlusion point of the molars M is determined (Fig. 9.4).