Krisztina Marton

The Individual Parts of the RPD1. Saddles

2. Occlusal rests and similar components3. Direct retainers

4. Connectors

SaddlesReplaces the lost alveolar tissues (flange) and

carries arteficial teeth (real saddle)Types:

BoundedFree end

Material of the fitting surfaceAcrylic resin

Disadvantageous to the health of the underlaying mucosa and the gingival margin of the remaining teeth

Metal, or metal-acrylic combination Provides better health of the mucosa because of the

metal’s highly polished surface, acrylic can provide acceptable esthetics

Connectors of the RPD

Upper archDistributes load to the

mucosa Butterfly Horseshoe Fenestrated Sceletonized Labial bar

Minor connectorsconnect small of the metal frame to the baseplate

Major connectorsconnect the two sides of the denture to eachother

• Lower arch– Not distributes load to

the mucosa• Lingual plate• ”finger type” lingual

plate• Lingual bar• Lingual bar with

continuous clasp (Kennedy bar)

• Sublingual bar• Dental plate• Labial (or buccal) bar

Lingual bar

Direct retainers of the RPDThese provide resistance to movement of the denture along the path of displacement and/or path of insertion and withdrawal during any function (hindering its removal of its supporting tissues

TypesCLASPS

Retentive clasp arms (usually incorporated in clasp units)PRECISION ATTACHEMENTS

ClaspsAs the denture is inserted, the flexible tip of the

retentive arm passes over the maximum bulbosity (the prosthetic equator) of a tooth and enters an undercut area.

Once the denture is fully seated, the clasp sits passively in its place , just contacting the tooth surface without forcing on it.

As the denture is subjected to displacing forces during function , the tip of the clasparm is drawn back towards the maximum bulbosity of the tooth . If the displacing forces do not exceed the level of lifting the clasp arm over the survey line the denture will stay in position

ClaspTypes:

gingivally aproachingocclusally aproaching

Material:Rigid: Cast metal (usually cast together with the baseplate)

Gold alloys Silver palladium alloys Cobalt cromium alloys Stainless steel Titanium

Elastic: Wrought wire (later adapted to the flange) Gold Stainless steel

clasparm

Clasp unit

Gingivally aproaching clasp

Occlusally aproaching clasp

Clasp unit