Retentive pin systems: a laboratory comparison of effectiveness of seating and other characteristics

An evaluation in vitro of a number of currently available pin systems used for retaining direct restorative materials was made in this study. The criteria used for evaluation of the systems were completeness of pin seating in the prepared channels and overall effectiveness of the design of the shoulder-stop-style pins. There was a wide range of difference in the ability to seat pins completely, and the seating of the shoulder-stops on the dentin floor was quite inconsistent.