Clinical Stage 1 Flashcards
1
Q
What are the stages of making a complete denture (include lab and clinical stages)
A
- Primary impressions
- Cast models and create special tray (LAB)
- Secondary impressions
- Cast models and create record rims (LAB)
- Jaw registration
- Mount on articulator and set up teeth (LAB)
- Try in
- Process to finish (LAB)
- Fit
2
Q
What makes a good impression
A
An impression should record the entire functional denture bearing area to ensure maximum support, retention + stability for the denture during use
3
Q
What anatomy should an upper primary impression have
A
- Hamular notch
- Vibrating line
- Fovea palatinae
- Torus paltaltinus
- Mucogingival line
- Buccal sulcus
- Palatal gingival vestige
- Labial sulcus
- Buccal frenum
- Labia frenum
- Incisive papilla
- Palatal rugae
4
Q
What anatomy should an lower primary impression have
A
- Retromolar pad
- Lingual sulcus
- Lingual frenum
- Buccal frenum
- Labia frenum
- Labial sulcus
- Buccal shelf
- Buccal Sulcus
- Pear shaped pad
5
Q
What is the vibrating line
A
Junction between immovable and movable tissue of the soft palate
6
Q
How can we identify where the vibrating line is
A
Get the patient to say ahhhhh
7
Q
What is the fovea palatinae
A
The bilateral indentation near midline of the palate
8
Q
How is the fovea palatinae formed
A
Coalescence of several mucous gland ducts
9
Q
Where is the fovea palatinae found
A
Posterior to the hard/ soft palate junction (vibrating line)
10
Q
What is the torus palatines
A
Harmless bony growth/ exostosis located on hard palate
11
Q
What is the palatal gingival vestige
A
Raided fibrous ridge on the palatal surface of upper residual ridge
12
Q
What can the palatal gingival vestige be used to do
A
Distinguish palatal mucosa from vestibular/ buccal mucosa
Can be used as a guide in positioning maxillary teeth
13
Q
How should a denture sit
A
- Sit on firm tissue
- Accommodate for bony undercuts
- Upper should extend to the vibrating line for a post dam
14
Q
What criteria must a primary impression fulfil
A
- Must record tissues without distortion
- Must be completed with minimal discomfort to patient
- Covers max denture bearing area
- Free of significance
15
Q
What makes a ‘bad’ denture
A
- Significant voids
- Under extension
- Over extension
- Impression material not adhering to tray
- Not covering full dentine bearing area
- Knife edged areas
16
Q
What is impression compound made up of
A
- Resin
- Plasticiser
- Filler
17
Q
How is Impression compound used
A
- Softened in a water bath
2. Placed in patient mouth then back into water Bath to soften
18
Q
What are the advantages of impression compounds
A
- Non toxic
- Easy to use
- Can be re softened
- Muco displasive
- Corrects gross tray problems
19
Q
What are the disadvantages of using impression compound
A
- Poor surface detail
2. Poor dimensional stability
20
Q
What are the advantages of alginate
A
- Easy to use
- Well tolerated
- Elastic
- Viscosity can be altered
- Good surface detail
- Mucostatic
21
Q
What are the disadvantages of alginate
A
- Poor stability after setting
- Cannot be added to
- Increases risk of drying out, shrinkage and syneresis
- increased risk of swelling and imbibition
- Poor tear resistance
- Requires adhesive to stick to tray
- Unsupported alginate
22
Q
What is alginate made up of
A
Irreversible colloid
23
Q
What is impression compound made up of
A
- Resins (Paraffin wax, beeswax, shellac)
- Filler (Talc and chalk)
- Plasticiser (Stearic acid)
24
Q
What is silicone putty made up of
A
Polydimethyl siloxane + platinum catalyst
25
What are the advantages of silicone putty
1. Easy to mic
2. Relatively easy to use
3. Moderate surface detail
4. Well tolerated
5. Elastic
6. Supports its own weight
7. Muco compressive
26
What are the disadvantages of silicone putty
1. Expensive
2. Needs tray adhesive
3. Long setting time
4. Hydrophobic
27
What do we put in out lab prescription after taking the primary impression
1. Draw tray outline approximately 2 mm short of periphery on impression
2. Decide on need for spacing or close fitting design
3. Upper handle slightly labially proclined
4. Lower vertical handle and finger rests in premolar region
28
What do we add onto special trays to take secondary impressions
Stops
29
What are the purposes of stops
1. Allows for space for material to flow out
2. Prevents build up of hydrostatic pressure
3. To ensure we get an even layer of material
30
If we forget to prescribe for stops in our special tray what can we do
Use green stick to make stops
31
What are the step we take for an upper occlusion rim
1. Liner upper rim with shellac
2. correct lip support
3. Adjust incisal level by getting the patient to smile
4. Ensure occlusal rim is parallel with inter pupillary line
5. Ensure occlusal im is parallel with Ala tragal plane
32
What is the ideal nano labial angle
90-100 degrees
33
How can we alter the lip support
By adding or removing wax
34
How can we ensure the occlusal plane is parallel interpupillary line
1. Using fox's guide plane
| 2. Standing in front of patient and asking them to look at your nose
35
Which occlusal rim should we do first upper or lower
Upper
36
What are the step we take for an lower occlusion rim
1. Line with thin light cure acrylic
2. Measure RVD using willis gauge
3. With both the upper and lower rim adjust the height to the correct OVD
4. Mark on midline with score levels in premolar region
5. Cut v notches on lower and upper models
6. Place silicone adhesive on lower model
7. Guide patient into RCP and get then to occlude
8. Seal models with blu mousse
37
What should the patients RVD be
At rest teeth should be slightly apart
38
What should the free way space be
2-4mm
39
How is the free way space calculated
RVD - OVD = FWS
40
After adjusting the occlusal rims what do you do
Select shade, size and shape of teeth
41
What are the aims of the wax try in
1. To identify and correct any errors prior to finish
| 2. Allow patient to assess appearance of dentures so any appropriate modifications can be performed
42
How is a wax try in placed to assess for errors
1. On articulator
| 2. In mouth
43
What do we check for on an articulator
1. Balanced occlusion
| 2. Balanced articulation
44
What do we check for when assessing balanced occlusion
All teeth meet evenly
45
When carrying out your wax try in the mouth what must we do between trials
Immerse the wax try in in cold water regularly
46
Which denture do we assess first the upper or lower
Upper
47
What do we look at when assessing a wax try in upper or lower individually
1. Retention
2. Stability
3. Extension of base
4. Relationship to neutral zone
48
How do we assess assess wax try ins relationship to the neutral zone
Check curve of Wilson and ridge position
49
What do we look at when assessing a wax try of an upper and lower denture together
1. Appearance
2. Occlusion
3. Free way space
50
What can happen if the base of the wax try in is over extended
Denture will displace
51
What can happen if the base of the wax try in is under extended
Poor retention for upper dentures
52
How can we correct an over extended wax try in base
Correct by decreasing 0ver extended flange
53
How can we correct an under extended wax try in base
Correct by taking a wash impression however this isn't idea and it would be better to back t secondary impression stage
54
Where should the flanges extend to on a wax try in
Extend beyond the full depth of the sulcus
55
What does accurate and correct flange extension ensure
Creates seal which will increase retention
| Makes movement of air and saliva slower decreasing displacement
56
What can happen if the flange width is too wide
Can decrease stability and traumatise soft tissues
| Air and saliva will move over the denture faster increasing risk of displacement
57
What is a too wide flange caused by
Excess green stick
58
How do we assess the lip support of a patient at the wax try in stage
Look at patient from all angles
| Ask patient for there opinion
59
What should the Naso labial angle be
90-110
60
How much of the incisors should be seen at rest
2-3mm
61
What happens to the level of the incisor seen at rest as age increases
Lip becomes less elastic so patient may show less teeth
62
What must we ensure the smile line and midline are parallel to
Alar tarsal line
63
How do we correct an unfavourable incisal level
Need to go back to wax rim phase
64
What are specific thing you look at when assessing a lower try in
Discomfort from the renal attachments, tori and mental nerves
65
What is the neural zone
The area where balanced forces from surrounding muscle (eg Tongue and cheeks) prevents the denture from unseating in function
66
Where should the tongue sit at rest when the denture is placed in
Tongue should lie just behind lower anterior teeth
67
How do we measure RVD
Get patient to place lower denture only
ask patient to relax
Use willis gauge
68
What do we check in regards to occlusion web both wax try ins are placed in the mouth
1. Check initial contacts in RCP
| 2. Check lateral and protrusive movements (but make sure patietn uses light movement)
69
Talk through the method of occlusal assessment for wax try ins
1. Visual
2. Patients perception
3. Articulating paper (be careful as teeth readily displaced int ax
70
What must we do if there is a problem with occlusion at the wax try in stage
Go back to wax rim stage
71
assess OVD How do we a
1. Insert the lower denture and measure RVD
2. Insert upper denture and measure OVD
3. Assess free way space at this point
72
What should you do if your free way space is inaccurate
1, Remove teeth and re record occlusion
OR
2, Go back to wax try in stage
73
Other than occlusion and aesthetics what else should we check when both wax try in are in the mouth
speech
74
How do we assess the patients speech with was try in
Ask patient to count from 60-70
If patients teeth drop then there's a problem with retention
If patients teeth click then there's a problem with the free way space
75
What does it suggest if the patietn struggles with saying the letter s
OVD is excessive or absent
76
What is an average free way space value
2-4mm
77
what can excessive free way space cause
1. Increased load on denture bearing tissues
2. Soreness of mucosa
3. Increased load on TMJ
4. Teeth clock together while speaking
5. Teeth constantly in contact
78
what can a lack of free way space cause
1. Over-closure to get teeth to meet
2. Difficulty eating
3. No teeth show
79
When a patient is assessing their appearance at the wax try in stage what should you remind them of
That this is the last chance for them to change their mind before the denture is finished
80
What must you make clear on the lab prescription If you wax try ins are successful
write clearly you wish for these wax try ins to be processed
81
What must we ensure we achieve by the end of the denture giving appointment
New denture should be as comfortable as possible:
1. No pain experienced by patients during insertion removal or occlusal contact
2. Teeth meet evenly
3. Dentures are retentive with good extension
82
In regards to patient understanding what should we check they know before leaving with their new dentures
1. How to control the dentures
2. Benefits and limitations of dentures
3. Denture hygiene
83
What do we check for on the denture surface before giving it to patietn
1. Sharp edges
2. Acrylic pearls
3. Undercuts
84
What do we check for upon insertion of new dentures
1. Fit and occlusion
2. Occlusion
3. Assess OVD
4. Free way sauce
5. Appearance
85
What can be some common causes of pain from a denture
1. Undercut flange which will traumatise mucosa
| 2. Acrylic spicules, nodules or sharp surfaces
86
How can we assess occlusion with dentures in situ
1. Tactile visual assessment
2. Feedback from patient
3. Articulating papaer (last resort)
87
when should we recall a patietn who we have given a new denture to
1 week
