RP 3 - Complete dentures opposed by natural teeth

Question 1

What can natural teeth occluding against an edentulous ridge lead to?

Answer 1

the presence of natural teeth means that excessive forces can be applied to the opposing edentulous ridge

leads to:
- trauma
- increased resorption
- lack of stability of dentures

Question 2

What is one of the main challenges when provided a complete denture that is opposed by natural teeth?

Answer 2

achieved a bilateral balanced occlusion
- uneven occlusal plane can result in inability to achieve balanced occlusion

Question 3

What will happen if you do not have a bilateral balanced occlusion for a denture?

Answer 3

the denture will tip and you’ll get excess lateral forces on the ridge which will lead to increasing resorption of the ridge

Question 4

If natural remaining teeth are worn, what can be a challenging when making a complete denture opposed by natural teeth?

Answer 4

might end up with an increase in the freeway space because you won’t be able to bring the opposing teeth on the denture either up or down far enough to compensate for that

Question 5

In what case may there be inadequate freeway space when making a complete denture opposed by natural teeth?

Answer 5

remaining teeth may have overerupted

Question 6

What can be difficult to record if the patient has an edentulous ridge opposed by natural teeth?

Answer 6

difficulty recording jaw relationship

Question 7

Why may aesthetics be compromised in a complete denture opposing natural teeth?

Answer 7

challenges with tooth position of denture teeth, particularly in the anteriors

Question 8

What can drifting of remaining teeth lead to?

Answer 8

can alter overjet or overbite, want to minimise the overbite in these cases as much as possible

Question 9

How does being opposed by natural teeth affect the wear of denture teeth?

Answer 9

denture teeth wear much quicker when opposed by natural teeth compared to being opposed by another denture

Question 10

What trauma may be caused the maxillary denture bearing area opposed by natural mandibular teeth?

Answer 10

• soft tissue damage
  
  • ulceration and discomfort
• alveolar resorption and fibrous tissue replacement
  
  • ‘flabby ridge’ / fibrous ridge
  • ‘combination syndrome’

Question 11

Where does fibrous ridge most commonly occur?

Answer 11

anterior maxilla

Question 12

What is ‘combination syndrome’?

Answer 12

where there are lower natural anterior teeth occluding against an edentulous upper ridge, leading to resorption of the anterior part of the ridge, and can also lead to overgrowth of the tuberosities as well

(debate around this but generally accepted)

Question 13

What issues are caused by a fibrous ridge?

Answer 13

tissue displacement (under denture and during impression taking) and tipping of the denture

Question 14

How would an impression be taken of a fibrous ridge that is not too severe?

Answer 14

use a special tray with perforations anteriorly to record a mucostatic impression of the tissues

Question 15

What is a mucostatic impression?

Answer 15

the shape of the tissues when they are at rest
- therefore denture should fit best when at rest

Question 16

What is a mucocompressive impression?

Answer 16

impression of the tissues under load
- denture will fit better under loading e.g. when eating, when patient is relaxed the denture has a high likelihood of dropping

Question 17

How would you take an impression of a more severe fibrous ridge?

Answer 17

2 stage silicone impression using a special tray with a window anteriorly

Question 18

How is a 2 stage silicone impression taken of a fibrous ridge?

Answer 18

take an initial first stage impression in putty and then cut away any excess putty that has gone around the fibrous ridge area and then carefully inject the light bodied material around the fibrous ridge to give a recording of that area in a mucostatic situation and then that can be used to construct the denture

Question 19

How is trauma to the maxillary denture bearing area opposing natural teeth minimised?

Answer 19

• construct a denture that is fully extended over the denture bearing area
• ensure that the denture will cover all of the primary load bearing sites

Question 20

It is vitally important an impression is fully extended but not overextended.

What areas is it particularly important to take the correct extensions of?

Answer 20

• labial sulcus
• buccal sulcus
• labial fraenum
• buccal fraenum
• hamular notch
• post dam

Question 21

What are you looking for when looking at the extensions of an impression?

Answer 21

• nice rounded edges
• no air blows

Question 22

What is the benefit of overdenture abutments?

Answer 22

• help to support the denture
• maintain the alveolar bone in those areas

Question 23

What can the affect be if the patient has only lower anterior teeth opposed by a complete upper denture?

Answer 23

• when the patient occludes the stability of the denture can be severely affected
  
  • when they occlude the posterior seal of the upper denture is broken and the back tips down as there are no teeth opposing it

Question 24

What can a large overbite of an upper complete denture lead to?

Answer 24

instability and tipping

Question 25

How is incisal overbite of an upper complete denture managed?

Answer 25

• position of the denture teeth (can sometimes lead to compromising aesthetics)
• reduction of the incisal edges of the natural teeth (if the OVD can’t cope with the positioning of the anterior teeth to minimise the overbite, e.g. the lower anteriors are overerupted)

Question 26

What is the effect of an irregular occlusal plane of the natural teeth?

Answer 26

inability to provide balanced occlusion for the denture against natural teeth, which can lead to a lack of stability, discomfort and difficulties eating, denture feeling ‘loose’

Question 27

How can an irregular occlusal plane on the natural teeth be managed?

Answer 27

• no adjustment (and do as best as you can with denture)
• minimal localised occlusal grinding
• radical occlusal adjustment (may involve crowning etc)
• extraction of teeth
• overlay appliance (overdenture)

Question 28

When may overlay appliances/overdentures we useful?

Answer 28

when teeth are quite worn and there is enough FWS to put denture over the teeth

Question 29

What has more severe issues: complete upper denture with lower natural teeth, or complete lower denture with upper natural teeth?

Answer 29

complete lower denture with upper natural teeth

Question 30

What issues can be caused when there is a complete lower denture with upper natural teeth, and why?

Answer 30

potential significant trauma to lower ridge due to:
- excessive occlusal forces
- occlusal imbalance
- minimal denture base foundation area (pressure not spread over as large an area)
- may lead to accelerated resorption of lower ridge

Question 31

How can issues from a complete lower denture with upper natural teeth be managed?

Answer 31

• soft lining
• retain roots and provide overdenture
• implants

Question 32

If a soft lining is provided what do you need to ensure?

Answer 32

patient must be aware they need extra care for cleaning and maintainence and if it’s not well maintained the lining will deteriorate quicker and need to be replaced quicker, it will go hard if not maintained properly