Complete Dentures Opposed by Natural Teeth

Question 1

easier option

Answer 1

complete upper denture opposed by lower natural teeth (rather than vice versa)

Presence of the natural teeth mean that high force levels can be developed against the upper maxillary edentulous ridge (can see evidence of trauma to upper anterior maxillary ridge)

Question 2

natural teeth against a denture leads to

2

Answer 2

trauma

instablity of denture
* additional forces and uneveness of natural teeth
* unable to get balanced occlusion
* loss of stability in functional movements (different from retention - denture staying in place in static situation)

Question 3

trauma which can occur to maxillary denture bearing area

2

Answer 3

abuse of soft tissues (mucous membrane damage, ulceration and discomfort under denture0

alveolar resorption and fibrous tissue replacement (due to prolonged abuse of soft tissues) - fibrous/flabby ridge

Question 4

fibrous/flabby ridge

Answer 4

tissue displacability
tipping of prosthesis

Question 5

‘combination syndrome’

5

Answer 5

Bone loss from the anterior part of the maxillary ridge,
Hypertrophy of the tuberosities
Papillary hyperplasia in the hard palate
Extrusion of the mandibular anterior teeth
Bone loss under the denture base

Kelly 1972

Question 6

how to reduce trauma to the maxillary denture bearing area

2

Answer 6

maximise coverage of denture bearing area by prosthesis

ensure prosthesis covers the primary load bearing sites

avoid being short in post dam area - less protection of alveolar ridge

Question 7

method to optimise load of denture beading area

Answer 7

Use of overdenture abutments
* Element of tooth borne support to complete upper denture and reduced ridge resorption in long term basis

Question 8

3 ways to ensure stablitiy of maxillary denture

key

Answer 8

Optimum border seal
* Decent primary and master imps and border moulding

Effective post dam
* Vibrating line between hard and soft palate
* 2nd post dam anterior – if cannot tolerate more posterior one

Effect of absence of the posterior teeth
* Managing partial lower harder – cannot cope, don’t wear
* Effect of absence of posterior teeth means more force against upper anterior teeth, break border seal and denture drops down
* Pt embarrassed in social situation as denture drops down

Question 9

maxillary denture opposed by a bounded mandibular saddle

Answer 9

ensure even occlsual plane, so increase stability of opposing maxillary denture

Question 10

maxillary denture opposed by mandibular free end saddle

Answer 10

stops tiliting on maxillary denture if provide a lower denture for saddle

hard for pt to cope with - may give up and thus decrease stabilty of maxillary denture

kennedy class 1

Question 11

incisor overbite

maxillary denture, lower natural

Answer 11

Mandible move forward and then displace/dislodge upper denture and reduce its stability

Natural and normal when natural opposing natural or fine in C/C but not C opposing natural

Question 12

2 options for managing incisor overbite

maxillary denture, natural lower

Answer 12

Reduction of the incisal edges of the natural teeth
* Make them shorter
* Not always possible - sensitivity

Siting of the denture teeth (higher up, so less seen on smiling)
* Improve function and stability
* But aesthetic compromised – show less teeth, and maxillary anterior key for appearance
* Compromise – what is best for individual pt`

Question 13

effect of an irregular occlusal plane on stability of maxillary denture

Answer 13

e.g Tx periodontal pt, drifting of teeth, Upper canine teeth hang down and incisors are higher

Trauma to ridge – undulating

Likely unstable upper denture when mandible in function

Question 14

assess what to ensure stability of maxillary denture

Answer 14

articulation in eccentric movements of mandible

points of contact can cause opposing denture to distabilise

aim for even bilateral contact in centric occlusion, regardless of unevenness in occlusal plane in maxillary denture opposed by natural mandibular teeth
* avoid concentrated force on one tooth as denture will lose stability

in C/C aim for even bilateral contacts (centric occlusion)

Question 15

how to manage irregular occlusal plane in natural teeth

5

Answer 15

• No adjustments
• Minimal localised occlusal grinding
• Radical occlusal adjustment
• Extraction of teeth
• Overlay appliances

need consent - can be hard to explain to pt need to alter natural teeth

Question 16

problems in complete lower denture opposed by natural upper teeth

Answer 16

much more severe
* stability already hard
* support area reduced due to tongue

significant trauma to lower ridge

Question 17

soft linings lower denture

Answer 17

can help - aid discomfort

become hard with time - need replaced approx 18months

Question 18

impressions for flabby ridge

Answer 18

Flabby ridge - displaced and so denture will move

Primary imp as usual in alginate
* Indicate where flabby ridge and draw on where it is
Request a tray with a window over the ridge

Usually close fit tray

Then master in 2 parts - ZOE or silicone material
* Cut out window material, reinsert and inject light body silicone to window

Mucostatic impression of flabby ridge
* Load applied to other areas of arch and avoid load on flabby ridge

in normal alginate impression compression of soft tissue occurs