Final Flashcards
(24 cards)
What are mechanical devices for mechanical retention?
box, groove, ferrule
What are supplemental devices for mechanical retention?
pins, amalgapins, post
A metal rod luted into a hole drilled in dentin to enhance retention is what type of pin?
cemented pin
A pin screwed into a hole drilled in dentin to enhance retention is..
self-treading pin
A metal rod driven into a hole drilled in dentin to enhance retention; retained solely by dentinal elasticity is a…..
friction retained pin
How should pins be placed?
2mm into the tooth and 2mm into the amalgam
What is a post?
Usually a metal material that is fitted into a prepared root canal of a natural tooth. When combined with an artificial crown or core, it provides retention and resistance for the restorations.
What is the purpose of post?
Retain a core in a tooth with extensive loss of coronal tooth structure.
Post width should not be greater than….
Post length should be…
1/3 of the root width; 2/3 length of the root.
How much gutta percha should remain apically to the post?
4-5mm
For maxillary teeth the post should extent into what root?
Lingual root
For mandibular teeth the post should extend into what root?
Distal root
What is the ideal and minimum crown to root ratio?
Ideal = 2:3, Minimum = 1:1
The combined root surface area of all abutment teeth supporting a fixed partial denture should be equal to or greater in root surface area than the tooth of teeth to be replaced. What law is this?
Ante’s Law
The feature of a tooth preparation that resists dislodgment of crown in a vertical direction or along the path of placement is the ________ form.
Retention
The feature of a tooth preparation that enhances the stability of a restoration and resist dislodgment along an axis other than the path of placement is the ________ form.
Resistance
What are indications for double abutments?
Unfavorable crown:root ratio and long span.
A natural tooth located between terminal abutments that save to support a fixed or removable prothesis is called a __________ abutment FPD. How many units does it have?
Pier; five
A bridge which has an abutment or abutments at one end only, with the other end of the Pontic remaining unattached is called a ________ FPD.
Cantilevered
What is the MAX # of pontics in Cantilevered FPD at all times?
ONE. No matter region of dentition.
In the first year following loss of teeth how much loss occurs in height and what percentage width in mandible?
First year following loss of teeth avg of 4mm loss in height and 30% width in mandible.
After initial healing residual ridge reduction in mandible continues at an annual rate of _____ to _____ in height. How much more resorption in mandible compared to maxilla?
.1mm-.2mm in height per year. Rate is four times more in mandible compared to maxilla.
Denture pts generate only ___% of the bite force generated by dentate individuals. Chewing efficiency is ___% that of dentate individuals.
20% of bite force; chewing efficiency 15-20%
What are the 6 appointments/steps for complete dentures?
Appt. 1 Clinic: review history, PAN, exams, etc.. + make preliminary impression with edentulous stock trays and irreversible hydrocolloid alginate material
Appt. 1 Lab: fabricate preliminary or diagnostic cast + custom trays
