Direct Retainers Part 1 Flashcards
____ retention:–Mechanical from retaining elements on abutment teeth
Primary Retention
____ retention:–Intimate contact of minor connector with guide planes–Intimate contact of denture base & maxillary major connector with underlying tissues
Secondary Retention
______: •RPD component used to retain and prevent dislodgement
Direct Retainer
•______ direct retainer
–Internal precision attachment: key/keyway
–Most esthetic
–Disadvantages: require crown, complex fabrication, & high maintenance
Intracoronal
•________ direct retainer
–Clasp assembly
–More commonly used
Extracoronal
–Retentive arm approaches undercut from above the survey line
–Circumferential, Akers, Circlet•Synonyms
Suprabulge
_____–Retentive arm approaches undercut from below survey line
–Bar clasps
Infrabulge
Which portion of the tooth is the reciprocal arm usually found on?
Lingual
Which portion of the tooth is the retentive arm usually found on?
Buccal
Which portion of the tooth is the rest usually found on?
Occlusal/Incisal
______ lies on occlusal, lingual, incisal surface–Prevent tissueward movement of clasp
Rest:
_____ components of direct retainer:
–Rigid component
–Above height of contour
–Reciprocal clasp, Lingual plate, Proximal plate, Guide plate (minor connectors)
Reciprocal components
_____ components of direct retainer:
•Proximal 2/3
•Rigid portion, above height of contour
Retentive clasp arm
_____ components of direct retainer:
•Distal 1/3
•Flexible•Below height of contour•Provides direct retention
Retentive terminal
- Joins body of clasp to framework
* Rigid
Minor Connector
- Component of bar clasp
- Connects clasp to framework
- Flexible minor connector
- Exception to rule
Approach arm
–Resist vertical movement toward tissue
–Rests
Support