Restorative Flashcards

1
Q

What are the causes of tooth surface loss?

A

Caries
Trauma
Developmental problems
Toothwear

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2
Q

What is the definition of tooth wear?

A

A normal physiological process that increases with increasing age

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3
Q

What is the definition of physiological tooth wear?

A

Normal wear associated with function

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4
Q

What is the estimated normal toothwear per year?

A

20-38 um

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5
Q

What is the definition of pathological tooth wear?

A

Occurs if the remaining tooth structure or pulpal health is compromised
The rate of tooth wear is excessive to the patients age
The patient may experience a masticatory or aesthetic deficit

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6
Q

What are the causes of tooth wear?

A

Attrition
Abrasion
Erosion
Abfraction

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7
Q

What is the definition of attrition?

A

The physiological wearing away of tooth structure as a result of tooth to tooth contact

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8
Q

Where are attritive lesions found?

A

On the occlusal and incisal contacting surfaces

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9
Q

What is the early appearance of attritive toothwear?

A

Polished facet on a cusp or slight flattening of an incisal edge

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10
Q

What does the progression of attritive toothwear lead to?

A

Reduction in cusp height
Flattening of occlusal inclined planes
Shortening of the clinical crown of the incisor and canine teeth

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11
Q

What habit is attrition associated with?

A

Bruxism

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12
Q

What is the definition of abrasion?

A

Then physical wear of tooth substance through abnormal mechanical process independent of occlusion.
Involves a foreign object or substance repeatedly contacting the tooth

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13
Q

What are the features of abrasion?

A

Site and pattern associated to the abrasive element
Labial/buccal, cervical on canine and premolar teeth
V shaped or rounded lesions

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14
Q

What is a common cause of abrasion?

A

Toothbrushing

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15
Q

What is the definition of erosion?

A

The loss of tooth surface by a chemical process that does not involve bacterial action

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16
Q

What are the features of early stage erosion?

A

Enamel surface affected
Loss of surface detail
Surfaces become flat and smooth
Bilateral, concave lesions without chalky appearance of bacterial acid decalcification

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17
Q

What are the features of later stage erosion?

A

Dentine becomes exposed
Preferential wear of dentine leads to ‘cupping’ of the molar surface and incisal edges of molars

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18
Q

What is the positioning and severity of erosive wear dependent on?

A

Source, frequency, and type of exposure to acid

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19
Q

What are the features of erosion?

A

Increased translucency of incisal edges (can appear dark)
Base of lesion not in contact with opposing teeth
Amalgam and composite restorations stand proud of the tooth
No tooth staining

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20
Q

What is the definition of abfraction?

A

The loss of hard tissue from eccentric occlusal forces leading to compressive and tensile stresses at the cervical fulcrum areas of the tooth

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21
Q

What are the two theories of abfraction?

A
  1. Abfraction is the basic cause of all non-carious cervical lesions
  2. Multifactorial aetiology; a combination of occlusal stress, abrasion and erosion
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22
Q

What are the causes of abfraction?

A

Caused by biomechanical loading forces that result in flexure and failure of enamel and dentine at a location away from loading

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23
Q

What is the impact of mechanical loading on enamel crystals (abfraction)?

A

Disruption of the ordered crystalline structure of the enamel and dentine by cyclic fatigue

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24
Q

What are the causes of cervical wear?

A

Multifactorial; tooth brushing

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25
Q

Where are cervical wear lesions usually?

A

Premolar and molars on the buccal surface (rarely lingually)

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26
Q

What is the most common type of tooth wear in older patients?

A

Physiological

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27
Q

What percentage of adults have wear in their anterior teeth (2009 Adult Dental Health Survey)?

A

77%

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28
Q

Which gender is toothwear more prevalent in? (2009 Adult Dental Health Survey)

A

Males: 70%
Females: 60%

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29
Q

What percentage of adults have severe tooth wear (2009 Adult Dental Health Survey)?

A

2%

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30
Q

What percentage of 5 year olds have tooth wear on their primary incisors? (2013 Children’s Dental Health Survey)

A

> 50%

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31
Q

How should tooth wear be assessed?

A

Recognise the problem
Grade its severity
Diagnose the likely cause
Monitor the progression; active or historic, are preventive measures working?

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32
Q

What are the features of C/O to be included in a tooth wear patient?

A

Aesthetic impairment
Functional difficulties (mastication, biting tongue or lips)
Pain

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33
Q

What are the features of C/O to be included in a tooth wear patient?

A

Aesthetic impairment
Functional difficulties (mastication, biting tongue or lips)
Pain

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34
Q

What are the features of a MH to be considered in a toothwear patient?

A

Medications with low pH
Medications that cause dry mouth
Eating disorders
Alcoholism
Heartburn
GORD
Hiatus hernia
Rumination
Pregnancy

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35
Q

What are the features of a DH that should be considered for a toothwear patient?

A

Dental attendance: poor attender/phobic not good candidate for complex tx plans
Precious experience/tx
Oral hygiene habits: toothbrushing

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36
Q

What are the features of a SH that should be considered for a toothwear patient?

A

Lifestyle stresses (bruxism)
Occupational details
Alcohol consumption
Dietary analysis
Habits
Sports

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37
Q

What are the features of an E/O exam for a toothwear patient?

A

TMJ; restriction of movement, clicking, crepitus
Hypertrophy of musculature
Restriction of mouth opening (<4cm)
Deviation during movement
Parotid hypertrophy
Overclosure
Lip line
Smile line

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38
Q

What features of occlusion should be checked in a toothwear patient?

A

Freeway space
Record OVD and resting face height
Is there dento-alveolar compensation
Record overbite and overset
Are there stable contacts in centric relation
What the tooth contacts are like in excursive movements

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39
Q

What features of an Intraoral exam should be done for toothwear patients?

A

Soft tissues- dryness, buccal keratosis, lingual scalloping
Oral hygiene
Perio assessment: BPE, pocket charting
Dental charting

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40
Q

What features of toothwear should you note in a wear examination?

A

Location: anterior/posterior/generalised
Severity: enamel only/into dentine/severe

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41
Q

What is a 0 on the Smith and Knight Toothwear Index?

A

No loss of enamel surface characteristics

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42
Q

What is a 1 on the Smith and Knight Toothwear Index?

A

Loss of surface enamel characteristics

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43
Q

What is a 2 on the Smith and Knight Toothwear Index?

A

Buccal, lingual and occlusal loss of enamel exposing dentine for less than one third of its surface
Incisal loss of enamel
Minimal dentine exposure

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44
Q

What is a 3 on the Smith and Knight Toothwear Index?

A

Buccal, lingual and occlusal loss of enamel, exposing dentine for more than one third of the surface
Incisal loss of enabler
Substantial dentine exposure

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45
Q

What is a 4 on the Smith and Knight Toothwear Index?

A

Buccal, lingual and occlusal complete loss of enamel, pulpal exposure or exposure of secondary dentine
Incisal pulp exposure or exposure of secondary dentine

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46
Q

What is a 0 on the Basic Erosive Wear Examination? (BEWE)

A

No erosive wear

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47
Q

What is a 0 on the Basic Erosive Wear Examination?

A

No erosive wear

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48
Q

What is a 1 on the Basic Erosive Wear Examination? (BEWE)

A

Initial loss of surface texture

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49
Q

What is a 2 on the Basic Erosive Wear Examination? (BEWE)

A

Distinct defect: hard tissue loss <50% of surface

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50
Q

What is a 3 on the Basic Erosive Wear Examination? (BEWE)

A

Hard tissue loss >50% of the surface area

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51
Q

How is the Basic Erosive Wear Examination (BEWE) risk level calculated?

A

Cumulative score of all sextants

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52
Q

Which arch is a Michigan splint for?

A

Upper arch

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53
Q

What is a Basic Erosive Wear Examination (BEWE) risk of none?

A

Cumulative score of <=2

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54
Q

What is a Basic Erosive Wear Examination (BEWE) risk of low?

A

Cumulative score 3-8

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55
Q

What is a Basic Erosive Wear Examination (BEWE) risk of medium?

A

Cumulative score 9-13

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56
Q

What is a Basic Erosive Wear Examination (BEWE) risk of high?

A

Cumulative score >14

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57
Q

What special tests can be carried out for toothwear patients?

A

Sensibility testing
Radiographs
Articulated study models
Intra-oral photographs
Salivary analysis
Diagnostic wax up
Dietary analysis

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58
Q

What are the features of generalised toothwear?

A

Wear with loss of OVD
Wear without loss of OVD, but with space available
Wear without loss of OVD, but with limited space

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59
Q

What are the immediate treatment options for toothwear patients with sensitivity?

A

Desensitising agents: fluorides, bonding agents, GIC coverage of exposed dentine

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60
Q

What are the immediate treatment options for toothwear patients with pain?

A

Pulp extirpation (if compromised pulpal health)
Smooth sharp edges (prevent trauma to cheeks and tongue)
Extraction (unrestorable)
TMJ pain

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61
Q

What are the initial treatment options for a toothwear patient?

A

Stabilise existing dentition
Deal with caries
Deal with Perio condition
Oro-mucosal
Preventive regime

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62
Q

What are the methods of baseline wear recording?

A

Wear indices: Smith and Knight, BEWE
Models
Photos

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63
Q

What can be done preventatively for abrasion patients?

A

Remove the foreign object or substance
Change toothpaste (less abrasive)
Alter tooth brushing habits
Change habits; nail biting, wire stripping, piercing/pen biting

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64
Q

What can be done preventatively for patient with cervical tooth brush abrasion?

A

RMGIC, GIC, composite or flowable restorations

RMGIC first choice (best survival), but aesthetically composite

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65
Q

What can be done preventatively for patient with cervical tooth brush abrasion?

A

RMGIC, GIC or composite restorations

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66
Q

What can be done preventively for patients with attrition?

A

Treat parafunction: cognitive behavioural therapy, hypnosis
Splinting

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67
Q

What are the advantages/disadvantages of hard/soft/michigan splints for attrition patients?

A

Hard splints: more robust, last longer
Soft splints: diagnostic device (shows wear facets as wears rapidly)
Michigan splint: hard splint; provides an ideal occlusion with even centric stops, has a canine rise which provides disclusion in eccentric mandibular movements

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68
Q

What can be done preventatively for erosion patients?

A

Fluorides
Desensitising agents (symptomatic relief)
Dietary management
Habit changes
Treat medical causes

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69
Q

What are the habit changes that can be implemented for erosion patients?

A

Stop swirling drinks in mouth
Drink with straws
Stop rumination (regurgitation of food)
Healthy eating - increased acidic fruit
Vegan diet - increased acidic dressings
Avoid sports drinks/gels

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70
Q

What can be done preventatively for abfraction patients?

A

Consider occlusal equilibrium
Fill cavities with low modulus restorative materials; RMGIC/flowable

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71
Q

What are the features of passive management?

A

Prevention and monitoring (around 6 months)

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72
Q

What are the features of active management of toothwear?

A

Simple restorative intervention

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73
Q

What are the goals of the of the active management of toothwear?

A

Preservation of remaining tooth structure
Pragmatic improvement in aesthetics
Functioning occlusion
Stability

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74
Q

What are the considerations to be made in the treatment planning for the active management of maxillary anterior toothwear?

A

The pattern of anterior maxillary tooth wear
Interocclusal space
Space required for the restorations being planned
Quality and quantity of remaining tooth tissue
The aesthetics demands of the patient

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75
Q

How is maxillary anterior toothwear categorised?

A

Toothwear limited to the palatal surfaces only
Toothwear involving the palatal and incisal edges with reduced clinical crown height
Toothwear limited to labial surfaces

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76
Q

In Maxillary Anterior tooth wear what may cause cases where there is adequate inter incisal space?

A

Teeth that wear rapidly and there is no time for alveolar compensation
Where there is an anterior open bite
Where there is an increased overjet

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77
Q

What would be the initial treatment aim for patients with maxillary anterior tooth wear?

A

Create space for traditional restorations

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78
Q

What are the treatment options for making space anteriorly?

A

Increase OVD
Occlusal reorganisation from ICP to RCP
Surgical crown lengthening
Elective RCT and post crowns
Conventional orthodontics

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79
Q

How can you increase the OVD in patients with anterior tooth loss?

A

Multiple posterior extra coronal restorations

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80
Q

What are the disadvantages of increasing the OVD in patients with anterior tooth surface loss?

A

Complex
Destructive
Expensive

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81
Q

What are the disadvantages of occlusal reorganisation from ICP to RCP in patients with anterior tooth surface loss?

A

Complicated
Destructive
Specialised treatment

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82
Q

What are the disadvantages of surgical crown lengthening in patients with anterior tooth surface loss?

A

Doesn’t really create more space

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83
Q

What are the disadvantages of elective RCT and post crowns in patients with anterior tooth surface loss?

A

Very destructive

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84
Q

What are the disadvantages of conventional orthodontics in patients with anterior tooth surface loss?

A

Lengthy treatment

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85
Q

What is surgical crown lengthening?

A

Exposure of more of the crown for retention of final restoration
Repositioning of the gingivae apically with removal of the bone
May cause sensitivity and need occlusal reduction

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86
Q

What is the DAHL technique?

A

Method of gaining space in cases of localised toothwear
Originally a removable CoCr anterior bite plane (now composite)
Covering palatal surfaces and allowing occlusion on raised cingulum
Results in posterior disclusion and increase in OVD of 2-3mm
Occlusal contacts only on incisor/canine teeth

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87
Q

What are the effects of the DAHl technique?

A

3-6months later
Gained space between incisor teeth
Interiors intrude
Posteriors erupt

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88
Q

What are the advantages of doing the DAHL technique with composite?

A

Better aesthetics
Better compliance
Easier to adjust
Immediate, definitive treatment

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89
Q

What are the features of the DAHL techniques success?

A

Faster effect in younger patients
Variable degree of effect
If no movement in 6 months; will not work
Success rate >90%

90
Q

What patients are not suitable for the DAHL technique?

A

Active periodontal disease
TMJ problems
Post orthodontics
Bisphosphonates
Dental implants
Conventional bridges

91
Q

What is the ideal patient for the DAHL technique?

A

Localised anterior tooth wear

92
Q

What is the ideal patient for the DAHL technique?

A

Localised anterior tooth wear

93
Q

What type of tooth loss should a splint not be provided for?

A

Erosion

94
Q

What is the definition of a bridge?

A

A fixed prosthesis that replaces lost or missing teeth

95
Q

What are the two main objectives of patient assessment for bridgework?

A

Determine the patient’s requirements and expectations
Determine the patients suitability for bridgework

96
Q

Why are periodical radiographs essential in bridgework?

A

Assess:
Alveolar bone levels
Width and completeness of periodontal membrane space
Root form and length
Extent and adequacy of coronal restorations
Pre-existing endodontic treatment

97
Q

What are three special investigations for bridgework?

A

Sensitivity testing
Periodical radiographs
Study casts

98
Q

What are the three objectives of a bridgework treatment plan?

A

Control and prevention of further disease
Satisfy patient expectations and requirements
Take account of long term maintenance

99
Q

What are the two main types of bridge?

A

Conventional
Adhesive

100
Q

Which type of bridge is more conservative?

A

Adhesive

101
Q

What are the three design types of bridges?

A

Fixed-fixed
Direct (rigid) cantilever
Fixed-movable

102
Q

Describe fixed-fixed design:

A

Retainers at each end of the edentulous span connected rigidly by the pontic

103
Q

Describe direct (rigid) cantilever design:

A

Pontic retained by a single retainer at one end of the span only

104
Q

Describe fixed-movable design:

A

Retainers at each end of the span joined by a moveable connector

105
Q

What should happen in the first appointment for a bridgework patient?

A

History and clinical examination
Upper and lower alginate impressions
Facebow transfer
Interocclusal record (if needed)
Periapiclas of abutment teeth
Complete laboratory prescription

106
Q

What is the laboratory prescription for the first bridgework appointment?

A

Please provide duplicate study casts in dental stone mounted on the articulator in ICP

107
Q

What should happen in the second appointment for bridgework?

A

Treatment options explained to patient
Consent obtained
Special tests if needed
May request a vacuum formed splint to provide an immediate provisional bridge following abutment preparation

108
Q

What should you do in the third bridgework appointment?

A

Take a pre-preparation putty index (for protemp)
Provide anaesthesia
Prepar bridge
Take post-preparation impression
Record the occlusion
Cement provisional or vacuum formed splint

109
Q

What should the lab card for bridgework post tooth preparation say?

A

Pour impressions
Explain the bridge design and material

110
Q

What should you do in the fourth bridgework appointment?

A

Try in and fit
Check bridge seats fully and doesn’t rock
Check marginal integrity
Check and adjust occlusal contacts
Ask patient to confirm approval of aesthetics and comfort prior to cementation
Cement (usually RMGIC) and removed excess
Provide cleaning instructions and post op instructions to patient

111
Q

What features should you look at in a bridgework review?

A

Marginal adaption
Occlusal function
Tissue response/effectiveness of oral hygiene measures

112
Q

What is the definition of a Pontic?

A

Artificial replacement of the missing tooth or teeth
May be made of porcelain, acrylic or metal

113
Q

What is the definition of a Retainer?

A

The restoration to which the Pontic is involved
Intra or extra coronal

114
Q

What is the definition of a Connector?

A

The device that fixes the Pontic to the retained
May be a soldered joint, cast structure, dovetail or stress breaker

115
Q

What is the definition of an Abutment?

A

Tooth or teeth that supports and holds the retainers.

116
Q

What is the definition of a Saddle? (bridgework)

A

The area between abutment teeth

117
Q

What is the occlusal reduction for porcelain and metal crowns?

A

2.5mm

118
Q

What is the occlusal reduction for a metal crown?

A

1.5mm

119
Q

What is the axial reduction for a metallic crown?

A

1.5mm buccal shoulder
5-7 degree taper

120
Q

What is the occlusal reduction for a ceramic crown?

A

2.5mm

121
Q

What is the axial reduction for a ceramic crown?

A

1.5-2mm buccal shoulder or chamfer

122
Q

What are the four features of a metal ceramic crown prep?

A

Lingual chamfer
Buccal shoulder
Functional cusp bevel
Occlusal reduction

123
Q

What are the features for a ceramic crown preparation?

A

Occlusal reduction
Chamfer margins
Axial reduction
Round line angles

124
Q

What are the 7 stages of crown preparation?

A

Occlusal reduction
Separation
Buccal reduction
Palatal or lingual reduction
Chamfer finish
Occlusion check
Polish

125
Q

What method can be used to get extra retention in a crown prep?

A

Grooves or slots prepared into the tooth

126
Q

What is the effect of longer crown prep walls?

A

Longer walls interfere with tipping displacement

127
Q

How can the retention of a crown be improved?

A

By limiting the number of paths of insertion

128
Q

What are the options of finish lines for crown preparation margins?

A

Knife edge
Bevel
Bevelled shoulder
Chamfer
Shoulder

129
Q

What are the important factors of crown prep to maintain periodontal health?

A

Margins: smooth and exposed to cleansing action, must be placed where dentist can finish them and patient can clean them

130
Q

What is the preparation for a metal crown?

A

0.5mm axial
0.5mm non functional cusp
0.5mm chamfer
1.5mm occlusal functional cusp

131
Q

What is the preparation for porcelain crowns?

A

1mm axial
1mm non functional cusp
1mm shoulder
1.5mm occlusal functional cusp

132
Q

What is the preparation for a metal ceramic crown?

A

1.3mm axial
1.3mm non functional cusp
1.8mm functional cusp
0.5mm chamfer (metal)
1.3mm shoulder (porcelain)

133
Q

What is the preparation for a ceramic crown?

A

1.5mm axial
1.5mm non functional cusp
1-1.5mm chamfer
2mm functional cusp

134
Q

What aspects of consent should be discussed to a crown patient?

A

Invasiveness of procedure
Possible complications
Costs involved
Likely longevity and success rate
Time involved
Alternative options

135
Q

What are the clinical stages of an indirect restoration?

A

Preparation
Temporisation
Impressions and occlusal records
Cementation

136
Q

What are the functions of provisional restorations?

A

Restore aesthetics and function
Prevent sensitivity and micro leakage of bacteria
Coronal seal of endo treatment
Preserve or improve function
Prevent drifting or tilting of prepared teeth
Maintain gingival health and contour
Isolation for RCT
Matrix for core build up

137
Q

What are the options for preformed provisional crowns?

A

Polycarbonate (silica)
Clear plastic
Metal

138
Q

What is the treatment option for anterior teeth with intact marginal ridges?

A

Composite restoration

139
Q

What is the treatment option for anterior teeth with intact marginal ridges and a discoloured crown?

A

Bleaching or Veneer

140
Q

What is the treatment option for anterior teeth with marginal ridges that are destroyed?

A

Core build-up with crown
Post crown

141
Q

What is the aim of a post/core?

A

Gains intraradicular support for a definitive restoration

142
Q

What does a core do?

A

Provides retention for a crown

143
Q

What does a post do?

A

The post retains the core

144
Q

When is a post unnecessary in incisors and canines?

A

If there is sufficient coronal dentine

145
Q

Why should a post be avoided in mandibular incisors?

A

Thin/tapering narrow mesiodistal roots

146
Q

Where should a post be placed in a premolar?

A

In the widest root cana
They have small pulp chambers and tapering roots

147
Q

What type of canals should you avoid placing a post in?

A

Curved

148
Q

How much root filling should be below a post?

A

4-5mm apically

149
Q

What is the specification for the width of a post?

A

No more than 1/3 root width at narrowest point
1mm circumferential dentine

150
Q

What is the minimum amount of post that should be in the root?

A

At least half

151
Q

What is the minimum ratio of post length: crown length

A

1:1

152
Q

What are the ideal dimensions of a ferrule?

A

At least 1.5mm height and width of remaining coronal dentine

153
Q

What is a ferrule?

A

Dentine collar

154
Q

What does a ferrule do?

A

Prevents tooth fracture

155
Q

What are the three ideal features of a post?

A

Parallel sided
Non-threaded
Cement-retained

156
Q

Why should a post be non-threaded?

A

Smooth surface incorporates less stress to remaining tooth than threaded

156
Q

Why should a post be parallel sided?

A

Avoids wedging
More retentive than tapered

157
Q

Why should a post be cement retained?

A

Less retentive than threaded posts but cement acts as a buffer between masticatory forces and post/tooth

158
Q

Which metals can be used as a post?

A

Cast gold
Stainless steel
Brass
Titanium

159
Q

What are the benefits/downsides of metals as posts?

A

Poor aesthetics
Root fracture
Corrosion
Nickel sensitivity
Radiopaque on radiograph

160
Q

Which ceramics can be used as a post?

A

Alumina
Zirconia

161
Q

What are the benefits/downsides of ceramics as a post?

A

High flexural strength
High fracture toughness
Favourable aesthetics
Difficult retrievability
Root fracture

162
Q

What fibres can be used as a post?

A

Glass
Quartz
Carbon

163
Q

What are the benefits/downsides of fibres as a post?

A

Flexible
Similar to dentine
Aesthetic
Retrievable
Bond to dentine (DBA)
Radiolucent on radiograph

164
Q

What are the options for a core material?

A

Composite
Amalgam
Glass Ionomer

165
Q

What are the benefits/downsides of composite as a core material?

A

Good aesthetics
Bonds to tooth
Technique sensitive
Moisture control needed
Fibre posts used

166
Q

What are the benefits/downsides of amalgam as a core material?

A

Poor aesthetics
Needs retention
24hr set

167
Q

What are the benefits/downsides of glass ionomer as a core material?

A

Absorbs water and swells

168
Q

How are posts removed?

A

Ultrasonic
Eggler device
Sliding hammer
Trephan: Masseran
Moskito forceps (screw-retained)
Anthrogyr (safe relax)

169
Q

What are the reasons for post failure?

A

60% restorative problems
32% periodontal problems
8% endo problems

170
Q

What are intrinsic causes of tooth discolouration?

A

Tetracylines
Pulp necrosis
Internal bleeding
Amalgam
Fluorosis

171
Q

What are the extrinsic causes of tooth discolouration?

A

Smoking
Coffee and tannins
CHX
Iron
Enamel defects

172
Q

What are the stages of crowns?

A

Preparation
Temporisation
Impressions and Occlusal Records
Cementation

173
Q

What is class 2 div 1 incisor relationship?

A

The upper incisors are proclined (increased overjet)
The lower incisors occlude posterior to the upper incisors

173
Q

What is class 1 incisor relationship?

A

The lower incisors occlude or lie immediately below the cingulum plateau of the upper incisors

174
Q
A
175
Q

What are the aims of occlusal reduction?

A

Retain some morphology but reduce cusps and marginal ridges

176
Q

Which burs should be used of occlusal reduction?

A

Diamond tapered fissure bur
Rugby ball bur

177
Q

What bur should be used for separation in crown prep?

A

Long tapered diamond bur

178
Q

What are the two planes used in buccal reduction?

A

1- using a diamond tapered shoulder bur
2- Same bur but follows the incline of the cusp

179
Q

What is the function of a core?

A

Gains intraradicular support for a coronal restoration

180
Q

What are the two types of post?

A

Preformed
Custom made

181
Q

What materials can be used as posts?

A

Cast metal (type IV gold/Au)
Steel
Zirconia
Carbon/glass fibre

182
Q

What are the features associated with length of a post?

A

More than or equal to crow height- 2/3 root length
4-5mm root filling left apically
Reaches alveolar crest

183
Q

What are the features associated with width of post?

A

No more than 1/3 of root width at narrowest point
1mm remaining circumferential dentine

184
Q

What are the features associated with width of post?

A

No more than 1/3 of root width at narrowest point
1mm remaining circumferential dentine

185
Q

What is the effect of occlusal trauma on a healthy periodontium?

A

Area of intermittent pressure and tension
Widening of pdl
Hypermobility
In absence of plaque, gingival margin remains intact

186
Q

What is the response of a healthy periodontium to occlusal trauma?

A

Pdl width increases until forces are adequately dissipated (increase in mobility)
Pdl width then stabilises and returns to normal if demand/forces reduce
If forces cannot be adequately dissipated, pdl continues to widen until tooth is lost (pathological failure of adaption)

187
Q

What is the effect of occlusal trauma on healthy but reduced periodontium?

A

Previous LoA and bone resorption
Tooth effectively on fulcrum

188
Q

What is the effect of occlusal trauma on a diseased periodontium?

A

Zone of co-destruction (physiological and pathological)
Occlusal forces cause PDL widening at base of pocket and may cause clinical attachment loss (pathological) or excessive bone loss (combination of pressure and pathology)

189
Q

What are the causes of mobility?

A

PDL width
PDL height
Inflammation
Shape/number/length of roots

190
Q

When is mobility unacceptable?

A

Progressively increasing
Symptomatic
Associated with deep pockets

191
Q

What is the treatment of mobility?

A

Treat perio/inflammation
Correct occlusal relations (selective grinding)
Splinting

192
Q

Why is splinting a treatment of last resort for mobility patients?

A

Causes OH difficulties
Does not influence rate of disease progression

193
Q

What are the reasons for teeth migration?

A

Unfavourable occlusal forces
Unfavourable soft tissue profiles

194
Q

What is the treatment of migration?

A

Accept and stabilise
Correct occlusal relations
Orthodontics
Treat perio

195
Q

When can anterior wear be restored definitively with confidence?

A

Relatively minimal and limited to palatal surfaces of teeth

196
Q

What are the conta indications in regard to restoring anterior wear?

A

Short roots
Reduced periodontal support due to Perio

197
Q

What feature of teeth affected by tooth wear has a positive influence on retention?

A

Enamel ring of confidence

198
Q

Which arch should be modified in order to increase the OVD?

A

Upper

199
Q

What is the treatment option of localised posterior tooth wear?

A

Filled directly with composite (no change in occlusion)

200
Q

How can composite build up focus on reestablishing canine guidance?

A

Adding composite resin to the palatal of upper canines to increase the canine rise and disclude the posteriors during lateral and protrusion excursions

201
Q

What are the stages of carrying out a composite buildup using a clear vacuum-formed matrix/stent?

A

Alginate impression
Diagnostic wax-up
Impression poured into stone
Vacuum formed clear matrix formed on this
Cut to size and used as mould for build up

202
Q

What factors are associated with the success of composite build up with a clear vacuum formed stent?

A

Good patient satisfaction
Posterior occlusion normally re-achieved
Seldom TMJ problems
No detrimental effect on pulpal health
No worsening of periodontal condition

203
Q

What factors affect the longevity of compite build ups carried out using a vacuum-formed stent?

A

Viable medium term option
Requires repair and maintainance (must inform pts)
Maxillary restorations last better than mandibular (increased bonding area)

204
Q

What information should you give patients about composite buildups?

A

Front teeth will receive tooth coloured fillings to cover the exposed and worn tooth surface (prev further toothwear)

No local anaesthetic used as there is no/minimal drilling to teeth

Possibility of improvement in tooth appearance

Bite may feel strange for a few days- difficulty chewing, only front teeth touch initially, then back teeth will touch again in a few months

Bite should feel normal after a week or so

May cause tenderness and/or lisping

Crowns/bridges/partial dentures will likely need replaces

205
Q

What information should you give patients about the longevity of composite build-ups?

A

Good longevity but chance of them debonding and falling off (can be replaced)

Requires maintainance; occlusal polishing, repair of chipping

206
Q

What three categories can generalised toothwear be divided into?

A

Excessive wear with loss of OVD
Excessive wear without loss of OVD but with available space
Excessive wear without loss of OVD and with no space available

207
Q

What can be used to assess a toothwear patients tolerance of an increased OVD?

A

Splint

208
Q

How should the OVD increase be split over maxillary and mandibular arches?

A

Half and half

209
Q

What type of generalised tooth wear should a specialist opinion be of benefit when treatment planning?

A

Excessive toothwear without loss of OVD with no space available

210
Q

What are the treatment options for excessive toothwear without loss of OVD with no space available?

A

Attempt to increase OVD by use of splints +/- dentures if lack of posterior support
Crown lengthening surgery
Elective endodontic
Orthodontics
Over dentures

211
Q

What are the down sides of crown lengthening surgery?

A

May result in black triangles
Unfavourable crown to root ration
Post op sense
Crown prep will be further down the root

212
Q

What are the downsides of overdentures in a toothwear patient?

A

Bulky
Difficulty keeping teeth and gingiva healthy

213
Q

What is the benefit of overdentures in tooth wear patients?

A

Preserve tooth substance and bone

214
Q

What are the features of risk management in toothwear?

A

Should be noted; whether stable or progressing
Advice should be given and recorded in patient notes aswell as patient compliance
Topical surface treatments should be recorded

215
Q

What are the features of consent for toothwear patients?

A

Patient must understand the proposed treatment inc passive prevention
Patient must understand their part in the treatment and how their co-operation is integral to a favourable outcome
The patient must understand the consequences of not following the advice given

216
Q

What are the features of consent for toothwear patients?

A

Patient must understand the proposed treatment inc passive prevention
Patient must understand their part in the treatment and how their co-operation is integral to a favourable outcome
The patient must understand the consequences of not following the advice given

217
Q

What are the indications for veneers?

A

Aesthetics
Peg-shaped laterals
Reduce or close diastemas
Hypoplasia or hypomineralisation
Erosion or abrasion
Fluorosis
Discolouration

218
Q

How long should you splint an avulsion/extrusion?

A

2 weeks