The angulation of the counterbevel is not as standard as that for the occlusal bevel. It is measured by the embracing angle, i.e. the angle between the bevel and the long axis of the crown. On the average, this angulation is from 30-70째, but it varies according to: a. The amount of indicated involvement for the facial or lingual surface. The more the desirable involvement there is, the less will be the embracing angle to preserve tooth structure. b. The amount of needed retention. The shorter the preparation walls (axial surfaces) less will be the embracing angle with the long axis of the tooth. In some situations, the counterbevel will almost be parallel to the intracoronal wall proper, which will add substantial the retention of the restoration c.
The type of cast alloy.
The less the castability of the alloy is, the greater will be the embracing angle, to allow for bulk of material marginally The extent of the counterbevel is least standardized in this part of the preparation.
Embracing angle The junction between these four different parts of the capped side should be definite, but slightly rounded, to improve reproducibility and to prevent stress concentration. 2. The Shoed part The shoed part of the preparation the facial or, , lingual , wall will be formed of three parts :
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