Circumferential Clasp - Wrought Wire with Cast Clasp
Posted on 12/02/2011
As noted in yesterday's blog, the cast circumferential clasp has a number of limitations. As a result, the combination clasp of a wrought wire retentive arm with a cast bracing/reciprocating arm was developed to address those limitations. Combination clasps are most popular for distal extension RPDs.
The most common indications for the combination clasp are:
1) Presence of tissue undercut below the abutment tooth precluding the use of a bar clasp.
2) Mesial tilt of the most distal abutment causing the guide plate to preempt the mesial rest in the I-bar clasp assembly.
3) Aesthetic requirements that cannot be achieved with the bar clasp due to its bulkiness.
Among the chief advantages of the wrought wire clasp are in its flexibility and adjustability. The major disadvantages include the cost (usually labs will charge extra as more time is required) and long term durability.
The most common indications for the combination clasp are:
1) Presence of tissue undercut below the abutment tooth precluding the use of a bar clasp.
2) Mesial tilt of the most distal abutment causing the guide plate to preempt the mesial rest in the I-bar clasp assembly.
3) Aesthetic requirements that cannot be achieved with the bar clasp due to its bulkiness.
Among the chief advantages of the wrought wire clasp are in its flexibility and adjustability. The major disadvantages include the cost (usually labs will charge extra as more time is required) and long term durability.
