Comparison of the retentive strength of two cast gold pin techniques

The retention contributed by the use of pins with gold castings can be substantially increased by the technique of placing a threaded pin in the dentin and making a casting with a threaded receptacle to fit the pin. The basis for the improvement is the greater retention of threaded pins to dentin compared to that of smooth, cemented pins that are part of the casting. The limitation on the retention achieved with the new technique is the cohesive strength of the cement. Zinc phosphate cement provided the highest retention, and EBA and polycarboxylate cements provided lower and similar retention when threaded pins were cemented to threaded receptacles.