Factors involved in complete denture

Question 1

Succses of CD

Answer 1

1- retention
2-stability
3- support

Question 2

What is retention?

Answer 2

Resistance of the denture to vertical movement

Question 3

Factors affecting the retention

Answer 3

1- anatomical f
2- physiological f ( viscosity and volume of saliva)
3-physical f
4-mechanical f
5-musculature f

Question 4

What are the anatomical factors

Answer 4

1-size of the denture bearing area ( when its increased the retention increases)
2-qualty of the stress bearing area
3- paraller walls ( prominent p wall w the buccu-libial wall will increase the surface area which will increase the atmocpheric p and will limit the range of displaced force)
4-undercuts

Question 5

Physical factors?

Answer 5

1- adhesion ( 2 dif molcuoles)
2-cohesion( the same 2 molecules like saliva when the cohesion increases that mans more saliva so less retension)
3- interfacial surface tension
4-atmospheric pressure
5- gravity

Question 6

Interfacial surface tension

Answer 6

Resetance to the sapperation between the dent and mucosa which will result in more contact

Question 7

atmospheric pressure and prepheral

Answer 7

For the atmospheric pressure to be affective the denture must have a perfec seal anround the brodare

Retentive force supplied by the atmospheric pressure is directly proportional to the area covered by the denture base

Question 8

Mechanical factor

Answer 8

Balanced occlusion
¡ Contour of polished surfaces
¡ Position of occlusal plane
¡ Position of the teeth in respect to the alveolar ridge

Question 9

aids in retention

Answer 9

Retentive springs
¡ Magnetic forces
¡ Denture adhesives
¡ Suction chambers
¡ Implants

Question 10

What is the stability?

Answer 10

Stable and constant position of the denture in the present of forces that act to disturbe it

Question 11

Factors affecting the stability

Answer 11

Retention
¡ Residual ridge anatomy (the square and tappired better than the ovoid )
¡ Residual ridge relationships (Normal residual alveolar ridge resorption pattern leads to increased crossbite relationship)
¡ Parallelism of the ridges
¡ Form and contour of polished surface
¡ Arch arrangement
¡ Neutral zone
¡ Occlusal plane ( inclines upward toward the pos mx—>upward and forwad md—> backward and downward)
¡ Occlusal harmony
¡ Neoromuscular control

Question 12

Support

Answer 12

Is a resistance of the denture base movement toward the ridge

Question 13

Area for support

Answer 13

Primary stress bearing area ;mx—> tubericty and hard palate
Md—> retromolar pad and buccal shelf area

Secondary ; mx—>rugae and alveolar ridge
Md—> anteror ridge and residual ridge

Question 14

How to maxmize the support

Answer 14

Surgical removal of pendulous tissue
¡ Use of tissue conditioning material
¡ Surgical reduction of sharp or spiny ridge
¡ Surgical enlargement of ridge
¡ Implants and overdentures

Question 15

Md bone height

Answer 15

Type 1—> 21 and more
Type 2 —> 20-16
Type 3—> 15-11
Typ4—> 10 or less

Question 16

Mx-md relationship

Answer 16

Class l is the normal one
Class ll vertical overlap
Class lll crossbite