Flabby Ridges

Question 1

Describe the ridge of a patient a class 5 howell and cawood ridge?

Answer 1

flat ridge form, inadequate height and width

Question 2

What should you consider when taking impressions of a class V ridge?

Answer 2

-in a class V, there is a flat ridge form with inadequate height and width. This means that very soft tissue is present
to maximise retention of your final form denture, it is important that during the impressions stage, when taking impressions the soft tissues should not be distorted by the impression material
-distorted tissue beneath the denture may also cause discomfort

Question 3

What is combination syndrome?

Answer 3

-dental condition commonly seen in patients with an edentulous maxilla and a partially edentulous mandible with preserved anterior teeth

Question 4

What are the hallmarks of combination syndrome?

Answer 4

• loss of bone from the anterior part of the maxillary ridge
• overgrowth of tuberosities (maxillary tuberosities)
• papillary hyperplasia in the hard palate
• extrusion of lower anterior teeth
• loss of bone under the free end saddle denture bases

Question 5

What kind of impression technique is contraindicated for use when taking impressions of flabby ridges ? Why is this?

Answer 5

• viscous impression material in a spaced tray
  *this is because it may distort the soft tissue which leads to the denture being unretentive and uncomfortable

Question 6

What impression taking technique is best indicated for taking impressions of flabby ridges?

Answer 6

The mucostatic technique

Question 7

What is a mucostatic technique ? What is the benefit of this technique?

Answer 7

• involves perforating the special tray where is covers the flabby areas
• it can also involve using a more fluid impression material
• it can also involve increasing the spacing of the tray
• it reduces the pressure caused by the impression material and thus will reduce the distortion

Question 8

What is a flabby ridge?

Answer 8

• fibrous tissue- bone replaced by fibrous tissue
• a superficial area of soft, mobile tissue
• replacement of bone with hyperplastic soft tissue

Question 9

Displacement of flabby ridges leads to a loss of ________ and _______ in complete dentures

Answer 9

retention and stability

Question 10

Outline the impression techniques that can be used for flabby ridges

Answer 10

• mucostatic
• mucocompressive
• selective pressure

Question 11

Give an example of a mucostatic impression technique

Answer 11

the window technique

Question 12

What type of impression material should you use for the main area in the window technique?

Answer 12

Medium bodied silicone

Question 13

What kind of impression materials can you use for the window in the window technique?

Answer 13

light bodies silicone
Syringable alginate

Question 14

What is the selective pressure technique?

Answer 14

• the selective pressure technique combines aspects of both the mucostatic and mucocompressive techniques
• pressure is applied to certain areas whilst little pressure is applied to other areas

Question 15

A knife edged atrophic, howell and cawood class IV ridge has…

Answer 15

good height
loss of width of the alveolar bone

Question 16

Class IV howell and cawood ridges tend to be …

Answer 16

mandibular

Question 17

What is the benefit of dentures created using the mucostatic impression technique?

Answer 17

dentire will fit alveolar tissue accurately at rest
will be comfortable at rest

Question 18

What is the disadvante of using the mucostatic impression technique?

Answer 18

occlusal pressure during contact will compress thicker fibrous areas and allow the denture to press hard on bony areas

Question 19

What kind of impression technique is best indicated for knife edge atrophic ridges? Why is this?

Answer 19

mucocompressive impression technique

this is because occlusal pressure will be transferred to thicker fibrous areas and pressure on bony sharp areas will be reduced

Question 20

What is a disadvantage of the mucocompressive impression?

Answer 20

it will not yield a dentuee with an accurate passive fit

Question 21

What is the mucocompressive impression technique ?

Answer 21

• special tray is made to fit closely to fibrous areas whilst there is spacing to bony areas- so soft tissue is distorted but bony sharp areas are relieved\
• viscous impression material is used. This compresses the fibrous areas where the tray is closely adapted but leaves spaces in the bony areas

Question 22

Give examples of materials that are used in closely adapted trays to give mucocompression

Answer 22

• zinc oxide eugenol
• medium bodied vinyl siloxane
• polyether

Question 23

Briefly outline features of the mucostatic impression technique

Answer 23

• spaced tray
• fluid impression material
• tissue uncompressed
• good passive fit
• good retention
• usually used for upper impression

Question 24

Briefly outline features of the mucocompressive impression technique

Answer 24

• closely adapted to fibrous areas, relieved in bony areas
• viscous impression material
• thick mucosa is compressed
• poor passive fit
• reduced retention
• comfortable under occlusal load
• usually used for lower impressiosn