66 - Basic principles of bridge restoration construction. Mechanical resistance. Periodontal base.

section

• parts of bridges

• when is bridges used?

• what occurs when tooth is lost? (godons phenomenon)
  

• talk about flexing

• talk about lever arm

• parts of bridges

• Retainer: part that seats on retainer tooth.

• Pontic: suspended member of the FPD that replaces missing tooth.

• Connector: provides connection between the retainer and the Pontic.

• Abutment tooth: tooth that provides support for retainer.

• when is bridges used?

• used when need for replacing missing teeth is obvious to patient. This happens when edentulous space is in both anterior and posterior regions.

• what occurs when tooth is lost? (godons phenomenon)

• When tooth is lost, structural integrity of dental arch is disturbed

• Leads to realignment of teeth until new state of equilibrium is reached

• Adjacent and opposing teeth of the edentulous space frequently move into it, especially those distal to the space

• Instead of drifting bodily, tilting movement is more common

• Teeth adjoining an edentulous space usually move but they do not always move

• talk about flexing

• Bridges with longer spans are less rigid so they can experience flexing

• to minimize flexing:

  • Pontic designs with greater occluso-gingival dimension.

  • Prosthesis may also be fabricated of an alloy with higher yield strength, such as nickel-chromium.

• talk about lever arm

• when pontic is outside of interabutment axis it can act as a lever arm