On these 2 crowns, the first porcelain and second gold, that I did last week in my office I show how I place retention grooves in my crown preparations to help lock my crowns in. These grooves prevent rotation and help secure the crowns in place. These slots allows for more surface area for the cement and results in a longer lasting restoration that holds firmly in place. This is especially important in short weak teeth. With this technique I am able to save teeth that otherwise would need to be extracted or require periodontal crown lengthening surgery.