Components of removable partial dentures - bracing Flashcards
What is bracing?
resistance to horizontal fore
only in seated position
What is stability?
the ability of the denture to be form or constant and to resist displacement by functional, horizontal or rotational stress
Are horizontal forces in the maxilla a problem?
not as much
much of it is transmitted to the palatal
What is reciprocation?
is resistance to the specific horizontal forces generated by a retentive clasp.
e.g. a bracing element is in contact with the side of the tooth opposite the retentive clasp
opposing surface of the active arm
Where does the reciprocating arm lie?
sit above survey line
What is indirect retention?
it is the resistance to rotational displacement on a tooth-and-mucosa borne denture
free-end saddle
What can provide indirect retention?
rest on a tooth anterior to the clasp
prevent tilt of denture
What are guide planes/surfaces?
they are flat surfaces, cut into enamel of teeth, which are parallel to the path of insertion of a denture
What is the purpose of guide planes?
improve retention and stabiloty of denture
resist vertical displacement
remove dead space/stagnation areas
Can you prepare for guide planes?
yes, can be prepared by adjusting contours of teeth to allow single straight line of insertion/removal of a saddle
What must guide planes be confined to?
enamel
How far away from gingivalmargin should guide planes be?
3 mm
How much should you remove from a tooth for guide planes?
0.5mm (green area)
should not be prepared as a flat plane (red area) - may penetrate into dentine, need resto
