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BDS4 > CDS Prosthodontics > Flashcards

CDS Prosthodontics Flashcards

1
Q

What are tooth analogues?

A

Dentures

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2
Q

Occlusion

A

The static relationship between the incising or masticating surfaces of the maxillary or mandibular teeth or tooth analogues

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3
Q

ICP

A

The complete intercuspation of the opposing teeth independent of condylar position/the best fit of the teeth regardless of the condylar position
A tooth position, so this can change throughout life depending on teeth lost and restorations placed

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4
Q

RCP

A

A condylar position, it is occlusion of the teeth occurring in the most retruded position, generally set for life unless sometime like a condylar fracture of the jaw joint occurs
You can usually guide a pt into this position

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5
Q

Index teeth

A

Contacting facets of teeth in ICP, often used to measure the quality of a natural occlusion, you need enough to have a stable occlusion

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6
Q

ICP compared with RCP

A

ICP - need sufficient index teeth and stable occlusion, may vary through life, depends on tooth relationships, sometimes more anterior than RCP (sometimes the same)
RCP - suitable for pts with insufficient index teeth or unstable occlusion, most reproducible position, is a condylar position

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7
Q

When would you register an occlusion in ICP?

A

If it is stable with sufficient index teeth

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8
Q

When would you register an occlusion in RCP?

A

If the occlusion is unstable and lacking sufficient index teeth

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9
Q

How to record an occlusal record

A

Bite reg paste - usually silicone paste
Wax wafer - modelling wax, tends to distort
Modified wax wafer - alminax, aluminium reinforced wax

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10
Q

When are record blocks required to record occlusion?

A

When there are insufficient index teeth

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11
Q

Types of record blocks

A

Wax
Wire strengthener
CoCr base
Shellac base - particularly useful for complete
Use wax built up to standard sizes in lab, then modify the block

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12
Q

How to modify record blocks?

A

Use either a bunsen burner or hot plate and a wax knife

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13
Q

What is used to register the occlusion between two record blocks?

A

Melted wax or bite reg paste

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14
Q

Modifying survey lines

A

Unfavourable survey lines can be improved for better clasping and improved retention by adding composite

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15
Q

Cendres and Metaux catalogue

A

Details the 100s of types of precision attachments

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16
Q

Where would a ball on post diaphragm precision attachment be used?

A

To add denture retention at a root treated retained root

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17
Q

Why is it important that good record keeping is done when using precision attachments?

A

There are hundreds of different types, sockets can become worn out or attachments can become loose in the acrylic
If these attachments need replaced it is important to know exactly which one was used in the past

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18
Q

If a tubelock and ball on post diaphragm are used in the same denture it is important that they share…

A

The same path of insertion

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19
Q

Two part denture

A

Two different paths of insertion
Can be useful when gross tissue loss

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20
Q

What can minute stain be used for when replacing lost soft tissues?

A

To recreate racial pigmentation

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21
Q

When are swing lock dentures usually used?

A

Kennedy class 1 bilateral free end saddles
Occasionally used in kennedy class 2 unilateral free end saddle

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22
Q

How do swing lock dentures work?

A

Engage bone and tissue undercuts for retention
Labial or buccal retaining bar, hinged at one end and locked with a latch at the other, with a reciprocal lingual plate

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23
Q

Solution for dentures for lingually tilted teeth

A

Buccal bar

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24
Q

Things that can help when making dentures for bruxists

A

Metal backing to teeth
Cobalt chrome reduces fracture
Metal-occlusal surfaces
Use of cross linked teeth as better wear resistance
Acrylic postdam increases retention

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25
Q

5 things to check at try in

A

Retention
Stability
Aesthetics
Extension
Occlusion

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26
Q

Common types of denture fractures

A

Midline
Tooth detaching from denture base
Loss of flange
Acrylic saddle detaching from Co/Cr baseplate
Clasp fracture - bend

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27
Q

Most common reason for denture fracture

A

Impact

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28
Q

Why do dentures fracture?

A

Impact
Acrylic in thin section
Work hardening of metal
Parafunction habits
Occlusion
Soft linings
Denture processing problems such as porosity
Bonding issues

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29
Q

Repair of a midline fracture of a complete denture

A

If fractured pieces can be located together, disinfect and send to the lab (no impression needed)
Cast poured, fractured area removed and new acrylic processed

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30
Q

Repair of a denture missing a piece such as an acrylic flange

A

Impression taken with fractured denture in the mouth, this is disinfected and sent to the lab, cast poured and new acrylic processed into the defect

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31
Q

Repair of denture tooth debonding from acrylic base

A

Self cure acrylic used chairside to reattach

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32
Q

What is retching?

A

Physiological mechanism
Involuntary contraction of the muscles of the soft palate or pharynx
Modified by higher centres in the medulla oblongata
Varies between pts

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33
Q

Two types of retching

A

Psychogenic
Somatic

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34
Q

What is psychogenic retching?

A

Retching may occur by sight, smell or sound of a dental surgery or thought of procedures like impressions

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35
Q

What is somatic retching?

A

Touching “trigger zones” commonly palatoglossal and palatopharyngeal folds, base of tongue, palate, uvula, posterior pharyngeal wall

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36
Q

Can a patient have both psychogenic and somatic retching?

A

Yes both can coexist, usually it is more one than the other

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37
Q

What can worsen retching during dental appointments?

A

Anxiety

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38
Q

When does retching become a problem? 4 examples

A

Impression taking
Jaw reg
Toleration of dentures
Denture retention, as the palate may be reduced

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39
Q

What is the main issue with palate reduction for retching patients?

A

Retention is compromised, leading to the denture falling down more, leading to more retching

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40
Q

Examples of passive relaxation tactics

A

Dim lighting, music, hiding dental instruments from pt sight

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41
Q

Examples of active relaxation tactics

A

Controlled rhythmic or relaxed abdominal breathing, distraction techniques

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42
Q

Important factors in the management of a retching patient

A

Identification of the problem
Identify trigger zones
Anxiety reduction
Patience and empathy
Sometimes additional treatments like CBT, acupressure or hypnosis

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43
Q

Examples of distraction for retching patients

A

Talking to the patient constantly about other things
Get patient to concentrate on lifting one leg or wiggling their toes
Get patient to press or tap their temple
Salt on tongue
As patient to close eyes or focus on one spot
Rinse mouth with very cold water just before

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44
Q

Examples of desensitisation techniques for retching patients

A

Repeated brushing or stroking anterior palate or tongue with finger/toothbrush
Swallowing with mouth open

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45
Q

Adjustments that can help impression taking in retching patients

A

Modify stock trays
Lower tray in upper arch
Modify special trays
Rapid setting impression materials

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46
Q

What might you use for a rapid setting impression material?

A

Dental composition or alginate mixed with warmer water

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47
Q

Denture design considerations for the retching patient

A

Is a denture really necessary - shortened dental arch
Horseshoe palate
Co/Cr less bulky than acrylic
Training plate
Short term use of essix retainer
Multiple postdams
Palate not too thick
Posterior cusps may need rounded so don’t stimulate dorsum of tongue
Consider no 2nd molars on denture

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48
Q

Most important factor in managing denture dissatisfaction

A

Managing expectations and explaining limitations BEFORE treatment

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49
Q

Most common problem with dentures that leaves patients dissatisfied

A

Issues with retention and stability

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50
Q

Are patients more often unhappy with upper or lower dentures?

A

Lower

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51
Q

Are patients more often dissatisfied with complete or partial dentures?

A

Partial (especially bilateral free end saddles)

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52
Q

Potential factors in denture dissatisfaction

A

Reduced self-esteem due to having to wear a denture and consequent negative impacts on socialisation
Aesthetic expectations unmet
Facial aesthetics changed due to tooth loss
Decreased chewing efficiency
Problems with denture stability and retention

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53
Q

Effective communication with pros patients

A

Listen to the pt
Know your subject
Avoid healthcare jargon
Be attentive
Answer questions
Respect confidentiality
Be empathetic

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54
Q

Risk assessment questions for how likely someone is to be satisfied with dentures

A

How long ago were your teeth removed?
How many dentures have you had since you lost your teeth?
How old is the last denture you had made?
Are you wearing the last denture you had made?

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55
Q

What to look out for when examining a patient for pros

A

Severely resorbed ridges
Flabby ridges
Tori
Prominent mentalis muscles, mylohyoid ridges, genial tubercles
High muscle attachments
Pain on ridge palpation

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56
Q

How to manage a patient with a compromised denture bearing area?

A

Effectively communicate that compromise is required and they will need to be realistic BEFORE treatment
Repeat key messages throughout treatment
Record what you say and the patient’s reply in the records

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57
Q

What is a dental implant?

A

An artificial tooth root that is surgically anchored into the jaw to hold a replacement tooth or teeth or a denture in place
The benefit of using implants is that they don’t rely on neighbouring teeth for support

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58
Q

Top to bottom

A

Abutment screw
Abutment
Implant

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59
Q

Top to bottom

A

Crown
Abutment
Titanium dental implant

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60
Q

Describe the interface that implant has with the body

A

No PDL
Direct communication between implant and bone, by osseointegration

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61
Q

Where should an implant sit if possible?

A

Crest of alveolar bone

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62
Q

Where does an implant abutment lie?

A

in the peri-implant mucosa, between the implant screw and crown

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63
Q

What is peri-implantitis?

A

Bone loss around implants

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64
Q

What is an implant abutment?

A

Component which screws into the implant, and has the crown attached to the top of it, with either cement or a screw

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65
Q

Why can implants be dangerous for bruxists?

A

No PDL and no proprioceptor fibres therefore the patient can not tell how hard they are biting/grinding

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65
Q

How are implant crowns joined to the implant?

A

An abutment is screwed into the implant and the crown is either cemented onto or screwed onto the abutment

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65
Q

What is the biggest difference between the function of implants and of natural teeth?

A

Implants have no PDL so there are no proprioceptor fibres

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66
Q

What is the significance of the number of joins/interfaces within an implant?

A

They are potential points of failure

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67
Q

Uses for implants

A

Single tooth
Multiple teeth
Securing a denture - implant overdenture
Eyes, ears, noses

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68
Q

Consideration when placing implants in the upper molar region

A

Maxillary sinus

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69
Q

Process of placing implants

A

Plan with radiographs
Raise flap
Place implant (with cover screw)
Suture
3 month wait
Uncover implant
Place abutment
Take imp, opposing arch imp and occlusal record
Choose shade
Place temp
Cement permanent when ready

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70
Q

What is a cover screw in implants?

A

Placed over the hollow part of the implant once it is placed and you are waiting to place the abutment, to prevent gingivae from growing in here

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71
Q

Advantages of screw retained implants

A

Simple to screw off if damaged eg chipped

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72
Q

Advantages of cement retained implants

A

Don’t have a screw hole through the restoration

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73
Q

Disadvantages of cement retained implants

A

Even with temporary cement, this can be very difficult to remove
Can get cement around the margins which can lead to inflammation and bone loss

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74
Q

Disadvantages of screw retained implants

A

Must be very careful with screw placement as screw hole would look bad if on labial aspect

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75
Q

Examples of implants for denture retention

A

Ball abutments
Locator abutments
Gold bar
CAD-CAM titanium bar
Magnetic retention

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76
Q

Advantage and disadvantage of gold bar implant

A

More resistance to rotation than locator or ball abutments
Difficult to clean under

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77
Q

Gold bar vs CAD-CAM titanium bar

A

Gold is more expensive
Titanium scanning and designing process time consuming
Gold has solder joints which could break
Both difficult to clean

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78
Q

Common post implant treatment complications

A

Peri-implant mucositis
Peri-implantitis
Loose/fractured components
Late implant failure

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79
Q

Role of GDP in implant patients

A

Oral health advice
Triage and diagnose (if possible) complications
Referral of the complication to an appropriately trained, indemnified and competent implant dentist
Manage taking account of SDCEP guidelines

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80
Q

What guidelines are there for GDPs managing implant patients?

A

SDCEP

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81
Q

3 points SDCEP guidance for maintenance of dental implants

A
  1. Ensure the patient is able to perform optimal plaque removal around the implant(s)
  2. Examine the peri-implant tissues for signs of inflammation and BOP and/or suppuration and remove supra-gingival and submucosal plaque and calculus and excess residual cement
  3. Perform radiographic examination only where clinically indicated
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82
Q

What is more difficult and why:
- Lower natural teeth opposing upper complete denture
- Upper natural teeth opposing lower complete denture

A

Upper natural teeth opposing lower complete denture
Lower dentures are poorly tolerated anyway
Presence of natural teeth mean that high force levels can be generated against opposing ridge, leading to trauma and instability
Lower ridge has less area to support and retain the denture, leading to worse trauma to this area and easier displacement

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83
Q

Why is it difficult to have natural teeth opposing a complete denture?

A

The presence of natural teeth means that high force levels can be generated against the edentulous ridge, leading to trauma and instability of the denture
An irregular occlusal plane opposing a complete denture can also be very problematic for stability

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84
Q

What is seen here?

A

Evidence of trauma to anterior maxillary ridge

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85
Q

Retention vs stability

A

Retention is the denture staying in place in a static position
Stability is the denture staying in place while functional

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86
Q

What are the consequences of trauma to an edentulous ridge denture bearing area opposing natural teeth?

A

Mucous membrane damage - ulceration or discomfort/pain, if this continues for a long time, a fibrous or flabby ridge can form due to alveolar resorption and fibrous tissue replacement

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87
Q

What is the issue with a flabby ridge?

A

Very poor for retention and support
Tissue displaceability leads to tipping of the prosthesis

88
Q

What is combination syndrome and when does it tend to occur?

A
  • Bone loss from 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
    When only lower anterior teeth are present
89
Q

How to reduce trauma to maxillary complete denture bearing area when it opposes natural teeth?

A

Maximise coverage of the denture bearing area by the prosthesis (as much hard palate coverage as possible)
Ensure prosthesis covers the primary load bearing sites

90
Q

What is the effect of retaining a couple of roots to use for overdenture abutments in a complete opposing natural teeth?

A

Gives an element of tooth borne support and optimises the loading of the denture bearing area, as well as reducing ridge resorption

91
Q

Options for improving stability in a complete opposing natural teeth

A

Optimum border seal - done by having good impressions including border moulding
Effective post dam - on vibrating line if pt can tolerate without retching

92
Q

What is the effect of a patient with only anterior teeth in the lower, refusing to wear a lower denture?

A

All the force from the lower is applied to the upper denture anteriorly, causing a significant amount of tilting, tending to break the border seal, causing the denture to drop

93
Q

How to manage an increased OB in a patient with complete upper dentures and lower natural teeth?

A

Reduce the incisal edges of the lower natural teeth but this can be problematic if sensitive OR sit the upper denture teeth higher up, this can improve stability and function but may be detrimental to aesthetics

94
Q

When do most issues with irregular natural occlusal plane opposing complete dentures occur?

A

In eccentric movements e.g. lateral

95
Q

Management options for an irregular occlusal plane opposing a complete denture (5)

A
  • Make no adjustments and accept
  • Minimal localised occlusal grinding
  • Radical occlusal adjustment
  • Extraction of teeth
  • Overlay appliances (rare)
    (good communication is required to gain consent for adjustments to the opposing arch)
96
Q

What can help with the discomfort caused by lower denture opposing upper natural teeth?

A

Soft linings

97
Q

How often can you expect a soft lining to need replaced?

A

18 months

98
Q

Considerations for uncomfortable lower denture opposing upper natural teeth

A

Soft linings
Implant overdenture such as ball abutments

99
Q

Examples of medical history that would make pt unsuitable for implants

A

Bisphosphonates
Radiotherapy
Unable to tolerate complex treatment

100
Q

Common denture fractures

A

Midline
Tooth detaching from base
Loss of flange (often when dropped)
Acrylic saddle detaching from CoCr baseplate
Clasp fracture/bend (often when dropped)

101
Q

Why do dentures fracture?

A

Impact - most common
Thin sections of acrylic - especially in palate
Work hardening of metal over time
Parafunctional habits
Occlusion - deep OB
Soft linings - take up space, thinner acrylic
Denture processing problems like porosity
Bonding issues such as between tooth and base or between acrylic and Co/Cr

102
Q

Examples of simple denture repair

A

Midline fracture of complete

103
Q

How to do a midline repair

A

If fractured pieces can be located together, disinfect and send to lab (no impression needed) cast poured, fractured area removed and new acrylic processed - straightforward
If a piece missing this is more difficult
Impression taken with fractured denture in the mouth, disinfected, denture and impression sent to lab, cast poured and new acrylic processed into the defect

104
Q

Management of acrylic tooth debonded from denture

A

If pt has the tooth - self cure acrylic can be used to reattach
If tooth is lost - tricky as needs to be matched shade and mould to the rest of the denture, and needs to be cut down to fit existing acrylic
Sometimes requires lab assistance

105
Q

What should you do if the same tooth keeps debonding from a denture?

A

Investigate why
May be problem with the bond or the occlusion
Denture may need redesigned

106
Q

Repairs for Co/Cr dentures

A

Can be difficult because the bond between acrylic and CoCr is not very good
Often the bits that break off are in the more vulnerable, weaker saddles
Sometimes necessary to add retentive tags by adjusting the chrome, soldering on tags or occasionally using materials like 4-META or silicoat CoCr to retain the acrylic

107
Q

What can be used for temporary repairs?

A

Self cure acrylic or cyanoacrylate glue (super glue)

108
Q

Example of common strengthener in the upper arch

A

Wire or glass fibre mesh embedded in the acrylic

109
Q

Example of common strenghthener in the lower arch

A

Stainless steel wire

110
Q

How do strengtheners work?

A

On the principle of having something ductile within something brittle

111
Q

Denture additions

A

Where something is added to an existing denture
Usually a tooth, or sometimes a clasp

112
Q

Types of additions

A

Immediate addition
Post immediate addition
Additional retention

113
Q

Immediate addition

A

Where a tooth is lost after denture construction and the tooth is added on the day of tooth extraction

114
Q

How to do an immediate addition

A

Take an impression with the denture in place and send this off to the lab
They will add the tooth onto this denture and you would extract the natural tooth before immediately refitting the denture

115
Q

Post immediate addition

A

Done where an immediate addition is not appropriate
Sometimes a tooth needs to come out immediately without a plan for it to be added to the denture having been made

116
Q

How to do a post immediate addition

A

Let the socket heal for 2 to 3 weeks following extraction, then take an impression with the denture in place and have the tooth added on to the denture

117
Q

What is usually used for an additional clasp and why?

A

Clasps are added when denture retention is inadequate
Wrought stainless steel used mostly because it is too difficult and complicated to add a CoCr clasp

118
Q

How to do a clasp addition

A

Take an impression with the denture in place, send this to the lab and cast will be made, then clasps will be made and added to the denture

119
Q

Clinical issues with denture additions

A

Additions usually require an impression with the denture to be added to in the mouth during the impression
Adding to CoCr dentures is more difficult than adding to acrylic
Sometimes you cannot add to a CoCr for example a lower incisor when a lingual bar connector is being used

120
Q

What materials are used to facilitate additions to CoCrs?

A

4-META or silicoat CoCr

121
Q

Advantage and disadvantage of flexible nylon based dentures

A

Get in and around undercuts well
Adding to or repairing is virtually impossible - due to weak bonding between tooth and nylon, these are generally short term - must build this in to consent process

122
Q

Do the properties of heat cure or self cure acrylic tend to be better?

A

Heat

123
Q

How does acrylic come from the supplier?

A

As a powder and a liquid

124
Q

What are the components in the powder for acrylic?

A

Polymer - PMMA beads
Initiator - benzoyl peroxide 0.5%
Pigments - salts of Cd/Fe or organic dyes

125
Q

What is the polymer in acrylic?

A

PMMA

126
Q

What is the initiator in acrylic?

A

Benzoyl peroxide 0.5%

127
Q

What is the liquid used to mix acrylic?

A

Monomer - MMA
Cross linking agent - ethyleneglycoldimethacrylate 10%
Inhibitor - hydroquinone
Activator (only in self cure) - N, N’-dimethyl-p-toluidine (1%)

128
Q

Why is it important to use the correct powder to liquid ratio when mixing acrylic?

A

Because of the amount of shrinkage
P:L 2.5:1 reduced shrinkage by 5-6%

129
Q

Stages of set of acrylic

A

Sandy
Stringy
Dough
Rubbery
Hard

130
Q

What kind of reaction is the set of acrylic?

A

Free radical addition polymerisation

131
Q

Important safety concern of setting acrylic in the mouth during additions

A

It is an exothermic reaction - might need to cool down with 3in1

132
Q

Why is it important to know the feeling of the stages of set of acrylic?

A

In case you are using self cure in the mouth, you must take it out when rubber to avoid a hard set with acrylic stuck in undercuts

133
Q

What temperature should be used for heat cure acrylic?

A

Over 65 degrees C to decompose the benzoyl peroxide but not more than 100.3 degrees because this is the BP of the monomer

134
Q

Advantages of acrylic

A

Cheap
Easy to add to, reline or repair
Technically easier to make than CoCr
Aesthetic

135
Q

Disadvantages of acrylic

A

Low impact resistance
Poor resistance to fracture fatigue unless very thick
Poor impact strength
Can feel bulky in the mouth
Water absorption and candida growth
Residual monomer irritant
Denture whitening due to alterations in microstructure
Risk to technicians

136
Q

Denture reline

A

Layer added when the fitting surface has changed shape slightly

137
Q

Denture rebase

A

Fully remaking the base of the denture

138
Q

Types of denture reline

A

Temporary
Soft
Permanent

139
Q

Where are denture relines done?

A

Can be chairside or in the lab

140
Q

Where are denture rebases done?

A

Usually in lab

141
Q

Example of when you would do a temporary reline

A

Ill fitting denture causing trauma to the ridge
Put a layer on the fitting surface to make it more comfortable to allow inflammation to subside, before making a new denture
(if you make a new denture when inflammation is still there it will not fit well)
Could also be used for post immediate dentures or after implant surgery

142
Q

Example of when you would use a soft reline

A

Parafunctional habits such as bruxists
Atrophic ridges
Cancer/cleft patients

143
Q

Why do soft linings not last very long?

A

Plasticiser leaches and it deteriorates over time, harbouring, harbouring microorganisms and potentially leading to increase in candidal infections

144
Q

Materials used for soft linings

A

Heat cured acrylics
Self cured acrylics
Heat cured silicones
Self cured silicones

145
Q

What material is usually used for a permanent reline?

A

Hard acrylic

146
Q

Uses for permanent relines

A

Correcting errors following inadequate master impressions
Immediate/post-immediate dentures
Prolongs lifespan of older dentures

147
Q

What is seen here and what would be the considerations in provision of dentures?

A

High buccal frenum (at the level of the alveolar process)
This would break the seal and displace the lower denture every time the patient moves their cheek

148
Q

How can milled crowns be used in combination with denture design?

A

They can be made to include rest seats, or sometimes palatal or lingual guide planes, and buccal undercuts suitable for CoCr clasps
Master imp is taken with crown in place, but it is not cemented until denture delivery

149
Q

What size of undercut is required for a CoCr clasp?

A

0.25mm

150
Q

Most common precision attachment types?

A

Studs and tubelocks

151
Q

Difficulties with precision attachments

A

Oral hygiene
Technical difficulties
Repairs and replacements - important to record exactly what precision attachment is used in the notes

152
Q

What is this?

A

Stud type precision attachment

153
Q

What is this?

A

Tubelock type precision attachment

154
Q

When would you use Duralay for provision of a crown?

A

When the patient has an existing partial denture

155
Q

Example of simplification of denture design

A

Anterior bridge to avoid single tooth saddle

156
Q

How to avoid dentures

A

Bridges, implants, acceptance of spaces

157
Q

Why might temporary dentures be used in toothwear cases?

A

To increase OVD and get patient used to wearing them, before providing crowns/build ups and then definitive dentures

158
Q

3 mechanisms by which dentures cause oral mucosal lesions

A

Acute or chronic reactions to microbial denture plaque
A reaction to constituents in denture base materials
Mechanical denture injury

159
Q

Examples of pathological changes caused by dentures

A

Ulcers
Denture stomatitis
Angular chelitis
Denture irritation hyperplasia
Flabby ridges
MRONJ/osteoradionecrosis
Allergic reactions

160
Q

How do dentures usually cause ulcers?

A

Mostly related to denture trauma
Could be new denture, or old one becoming ill fitting over time
Overextension
Sharp edges

161
Q

Common sites for denture trauma induced ulceration

A

Lingual frenum
Mylohyoid ridge
Undercuts

162
Q

How to manage denture trauma induced ulceration

A

IDENTIFY - pressure indicating paste, articulating paper
EASE - occlusal adjustment, trim and polish base
REVIEW to check that ulcer is gone

163
Q

Appearance of denture stomatitis

A

Red
Oedema and erythema

164
Q

Most common microbial cause of denture stomatitis

A

Candida albicans
Often associated with poor denture hygiene

165
Q

Management of denture stomatitis

A

Denture hygiene advice (take denture out at night, clean with soft brush, steep denture) possible use of chlorhexidine mouthwash, use of nystatin or other appropriate antifungal, consider new denture
Consider underlying issues eg diabetes, folate, B12, ferritin

166
Q

What other condition often coexists with angular chelitis?

A

Denture stomatitis

167
Q

Features of denture/patient often associated with angular chelitis

A

Overclosure eg loss of OVD/excessive FWS
Old worn dentures (often replace)

168
Q

Microorganisms associated with denture stomatitis

A

Candida albicans
Staph. aureus
Beta-haemolytic streps (eg. streptococcus pyogenes)

169
Q

Miconazole important drug interaction

A

Miconazole inhibits the metabolism of the coumarin anticoagulants, resulting in increased anticoagulant effects. The interaction between miconazole and coumarin anticoagulants is a well established serious drug interaction

170
Q

When is denture irritation hyperplasia most likely to be seen?

A

Old ill fitting dentures
It is a hyperplastic response to chronic trauma

171
Q

Management of denture irritation hyperplasia

A

Major ease of denture - tissue conditioner like coe comfort
Review and repeat if required
Once tissue has shrunk back make new denture
(if tissue won’t shrink back, refer for surgery)

172
Q

Cause of flabby ridge

A

Excessive force leads to trauma from denture, causes bone resorption leading to fibrous replacement resorption

173
Q

Most common flabby ridge

A

Anterior maxillary ridge when only lower anterior natural teeth remain (combination syndrome)

174
Q

Solution for flabby ridge

A

New denture covering whole denture bearing area with good peripheral seal AND opposing arch denture giving posterior support
Occasionally you will need special impression techniques as it can be difficult to get a good impression of a flabby ridge

175
Q

Why is an ill fitting denture in patient on anti-resorptive medication a huge issue?

A

MRONJ

176
Q

Why is important that patients who have had head or neck radiotherapy have well fitting dentures?

A

Risk of ORN on trauma

177
Q

How to manage denture wearing anti-resorptive or head and neck radiotherapy patients?

A

Review regularly for oral health checks
Prevent MRONJ/ORN by well fitting dentures
Refer promptly to Max Fax if ORN or MRONJ

178
Q

Why is allergic reaction to denture base material hard to diagnose?

A

Often redness of denture bearing area with similar appearance to denture stomatitis
Differentiated because allergic reaction can appear on lips and cheeks also

179
Q

Why is self cure acrylic more likely to cause irritation?

A

Higher proportion of monomer

180
Q

Why is effective communication with the lab important?

A

It is in the GDC standards that you must work effectively with your colleagues and contribute to good teamwork AND communicate clearly and effectively with other team members and colleagues in the interests of patients

181
Q

GDC Dental technician scope of practice

A

Dental technicians are registered dental professionals who make dental devices to a prescription from a dentist or clinical dental technician
They also repair dentures direct to members of the public

182
Q

What does the GDC say about delegating?

A

You can delegate the responsibility for a task but not the accountability. This means that, although you can ask someone to carry out a task for you, you could still be held accountable if something goes wrong.
You should only delegate or refer to another member of the team if you are confident that they have been trained and are both competent and indemnified to do what you are asking.

183
Q

Key features of a lab prescription

A

Pt identifier such as name and DOB
Date
Your name
Date of next appt
What you are making e.g. F/F -/P, lower soft splint
Note clearly if an immediate denture as well as which teeth are to be extracted
At each stage indicate disinfection

184
Q

Special tray lab prescription

A

Material to be used - commonly acrylic, specify if different
Spacer - usually 3mm, exception for close fitting tray in complete dentures for use with ZOE or light/medium bodied silicone
Tray handle and/or finger rests - intra-oral/standard/large handle
Special instructions e.g. horsehoe tray

185
Q

Record block lab prescription

A

Do you need upper and/or lower
Base e.g. wax, wire strengthener, CoCr, shellac, etc

186
Q

When might you not need record blocks?

A

If you have enough index teeth to hold the cast together

187
Q

Partial denture design for the pros lab

A

Prescribe for primary cast to be surveyed and articulated
Indicate design clearly on card and on primary cast
Indicate material of base e.g. CoCr or acrylic and materials for other elements e.g. clasps

188
Q

Try in lab prescription

A

Shade
Mould
Cusped/cuspless teeth
Setting
Individual requirements eg. 1mm diastema or no 7s

189
Q

Finish lab prescription

A

Postdams - where (indicate on cast) and how many?
Relief areas - tori, bony exostoses, overdenture abutments
Soft lining?
Type of acrylic - high impact, heat cured
Special requirements e.g. gum contouring

190
Q

What is MHRA?

A

Medicines and healthcare products regulations authority - pros labs must be registered with them

191
Q

What must be offered to patient with their denture?

A

Statement of manufacture
Lab produces this, clinician is responsible for offering it
Note down in records, keep a copy

192
Q

Acrylic vs CoCr for perio patients

A

CoCr less periodontally destructive (by keeping the CoCr away from as many gingival margins as poss) but difficult to add to
Acrylic more periodontally destructive but easy to add to

193
Q

What must be considered when designing a partial denture for a perio patient?

A

Cross as few gingival margins as possible
Reduce tissue coverage where possible

194
Q

Why is important to keep key teeth in perio patients and which teeth are these likely to be?

A

For appropriate support and retention for partial dentures
Particularly useful teeth are often canines/premolars and lone standing molars

195
Q

What is seen here?

A

Solution for a very periodontally compromised lone standing molar
Tunnel crown prep as there has been bone loss down to the furcation
This crown is also designed with a mesial rest seat and a buccal undercut with future denture retention in mind

196
Q

Which are most often the last teeth to be lost?

A

Lower anteriors

197
Q

What are the pros/cons of a perio patient wearing a lower denture when the lower anteriors remain?

A

Denture may increase plaque build up around the remaining teeth and perhaps hasten their deterioration BUT it is important that the patient gets denture wearing experience
Coping with a complete lower is difficult and pts should prepare for this if possible
Also may help with flabby ridge caused by edentulous maxilla opposing lower anteriors

198
Q

Difficulties of prosthetic techniques on mobile teeth

A

Impressions - may need to use wax in undercuts
Tooth position - periodontally involved teeth may have drifted significantly, if extracting where will you position them on the denture?
Loss of bone and soft tissue
Path of insertion
CoCr precision fit - teeth may be distorted during impressions
Must INFORM TECHNICIAN OF MOBILE TEETH

199
Q

Pros and cons of perio pt wearing a denture

A

Providing no prosthesis is often less damaging periodontally, which can prolong the life of the natural teeth BUT lack of posterior support increases tooth mobility of remaining teeth and the patient will have a lack of denture wearing experience

200
Q

Dry mouth and dentures

A

Many patients take anti depressants or a polypharmacy, leading to dry mouth
Saliva is important in denture retention, and denture wearing in dry mouth can give pain and discomfort due to lack of lubrication
Candica/angular chelitis etc are associated with xerostomia

201
Q

Anaemia and dentures

A

Associated with denture stomatitis, angular chelitis, pain and discomfort

202
Q

Tremors and dentures

A

Parkinson’s/CVA/Huntingdon’s chorea
Sudden involuntary movements make stages of construction eg. jaw reg difficult
Better to give simpler treatment plans

203
Q

Anti-resorptive drugs and dentures

A

Ill fitting denture can contribute to MRONJ
Patients on these drugs often have retained teeth or roots that you wouldn’t normally have kept, because extractions have been avoided. This can make denture design and construction quite difficult.
Always refer to SDCEP guidance for patients on these drugs.

204
Q

Frailty NICE definition

A

a state of increased vulnerability to poor resolution of homeostasis after a stressor event

205
Q

Legislation for those who lack capacity

A

Adults with incapacity (Scotland) Act (2000)

206
Q

Examples of questions you could ask to deduce whether a patient has capacity

A

How old are you?
What is your DoB?
What is this place?
What year is it?

207
Q

What certificate can dentists (with the appropriate training) fill out for adults with incapacity?

A

Section 47 certificate

208
Q

Vulnerable adult

A

unable to safeguard their own wellbeing, property, rights or other interests and are at risk of harm, and because they are affected by disability, mental disorder, illness or physical or mental infirmity, are more vulnerable to being harmed than adults who are not so affected.

209
Q

Harm

A

Physical, psychological, financial, sexual, neglect and acts of omission

210
Q

Legislation for vulnerable adults

A

Adult support and protection (Scotland) Act 2007

211
Q

Is a partial acrylic or partial CoCr usually a better intermediate denture to transition the pt into becoming edentulous?

A

Partial acrylic because it is easier to add teeth on

212
Q

Lower CoCr connector for periodontal health considerations

A

Lingual plate - easier to add to
Lingual bar - less gingival margin coverage

213
Q

How do antidepressants cause xerostomia?

A
214
Q

What is NICE

A

National Institute for Health and Care excellence

215
Q

What is ECOG used for?

A

It describes a patient’s level of functioning in terms of their ability to care for themself

216
Q

4 most common types of dementia

A

Alzheimer’s disease
Vascular dementia (20%)
Dementia with Lewy bodies (15%)
Fronto temporal dementia (5%)

217
Q

Dementia

A

Dementia is not a disease in itself
The term dementia is used to describe a collection of symptoms cause by disorders affecting the brain
There are more than 100 different disorders causing dementia

218
Q
A

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