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Flashcards in Quiz 2 Review Deck (95)
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1
Q

what are some of the indications for an FPD?

A
  • medical contraindication to implants
  • grossly inadequate alveolar bone for implant placement
  • treatment following implant failure
  • patient time constraints and/or circumstances that preclude implant placement
  • patient that does not want an implant
2
Q

of partial coverage and full coverage bridges, which is more retentive?

A

full coverage

3
Q

what is an abutment tooth?

A

the tooth that supports the FPD

4
Q

what is the retainer part of an FPD?

A

the crown

5
Q

what is a pontic?

A

the missing tooth

6
Q

what is the connector on an FPD?

A

the joint between the teeth

7
Q

what is a splinted crown useful for?

A

teeth that are going to be abutments for an RPD, perio/mobility, or increased retention

8
Q

what are the disadvantages of splinted crowns?

A
  • flossing is compromised
  • if one fails, they both fail
  • retrievability is complicated
9
Q

label this

A
10
Q

T or F:

all of the same factors that influence resistance and retention for single units apply to fixed bridges

A

true

11
Q

retainers with increased ___ height are more retentive than retainers with decreased ___ height

A

axial wall, axial wall

12
Q

does increased abutment taper increase or decrease the resistance and retention of the retainers?

A

decreases

13
Q

why is abutment taper of increased out of necessity? what can this increased axial wall taper create?

A
  • to align abutments and allow a path of insertion
  • it can create extra stresses on pulpal tissues
14
Q

part of the pre-operative assessment for fixed bridges should always include the alignment of the proposed ___

A

abutment teeth

15
Q

what are 5 fixed bridge designs?

A
  • pier to pier (pier refers to the abutment)
  • pier to pier to pier
  • cantilever
  • keyway feature
  • combinations
16
Q

why should you avoid the pier to pier to pier fixed bridge design?

A

the terminal abutments will often loosen and the middle abutment becomes a fulcrum

17
Q

T or F:

a double abutment refers to two abutment teeth right next to each other, which is a better option than a pier to pier to pier design

A

true

18
Q

how many pontics can be used in a cantilever bridge?

A
  • one pontic only
  • this is not an absolute, but will keep you out of trouble
19
Q

with cantilever bridges, where should the pontic be? what is the exception?

A
  • the pontic should be mesial to the retainer
  • except maxillary central carrying a maxillary lateral
  • this is not an absolute, but will keep you out of trouble
20
Q

which two single abutments cannot be used with cantilever bridges?

A
  • mandibular incisor or maxillary lateral incisor
  • this is not an absolute, but will keep you out of trouble
21
Q

___ rests should be used when possible with cantilever bridges

A
  • cingulum/marginal ridge rests
  • this is not an absolute, but will keep you out of trouble
22
Q

based on clinical results of a 2-unit cantilevered resin-bonded fixed partial denture, they are found to be a durable prosthesis over the long term with high patient satisfaction. what is the consideration with the posterior prosthesis?

A

it has a higher failure rate, and improved design features should be considered (the janis bridge)

23
Q

list 11 factors to consider with bridges

A
  • parafunctional habits
  • periodontal health
  • plaque control/caries susceptibility
  • occlusion
  • root angulation
  • root form
  • root surface area
  • retrievability
  • crown/root ratio
  • length of span
  • endodontic health
24
Q

what are 6 occlusion considerations for bridges?

A
  • is the TMJ complex healthy?
  • are the condyles seated?
  • are occlusal forces controlled?
  • does the bridge involve the patient’s anterior guidance?
  • is an occlusal adjustment indicated?
  • should splint therapy be considered?
25
Q

what are parafunctional considerations for bridges?

A
  • accelerated occlusal wear?
  • tooth mobility?
  • temporomandibular pain?
  • tooth fracture?
  • are the same factors that contributed to the tooth loss unresolved?
26
Q

whata re root angulation considerations for bridges?

A
  • are the roots in line with occlusal forces?
  • if not, how much off angle is acceptable?
  • is orthodontic uprighting necessary?
  • us orthodontic uprighting possible?
27
Q

if root angulation is off, what is it sometimes necessary to do in preparation for a bridge?

A
  • recontour the proximal contacts of adjacent teeth
  • prepare abutment teeth off-axis
28
Q

if root angulation is off, pre-operative ___ therapy can significantly enhance long-term prognosis of prosthodontic therapy

A

orthodontic

29
Q

what are root form considerations for bridges?

A
  • conical and short vs irregular and long?
  • are there thin areas, especially concavities, that are especially prone to fracture?
30
Q

what is ante’s law? what year was it developed? what is the exception?

A
  • the total periodontal membrane area of the abutment teeth must equal or exceed that of the teeth to be replaced
    • in other words, the total root surface area of the teeth to be replaced should not be greater than the total root surface area of the abutment teeth
  • 1926
  • really long canines are the exception
31
Q

ante’s law is useful for determining ___ of fixed dental prostheses

A

prognosis

32
Q

with respect to percentage of root surface area per quadrant, the maxillary central and lateral incisors together make up about ___% of the total for the maxilla, and the mandibular central and lateral incisors together make up about ___% of the total for the mandible.

A
  • maxilla: 19% (central = 10, lateral = 9)
  • mandible: 17% (central = 8, lateral = 9)
33
Q

which tooth overall has the greatest PERCENT root surface area?

A

mandibular first molar

34
Q

which tooth overall has the greatest root surface area?

A

maxillary first molar

35
Q

with respect to crown/root ratio, the ___ of roots accelerates the negative impact of crestal bone loss

A

conical shape

36
Q

the deflection of a fixed dental prosthesis is proportional to the ___

A
  • cube of the length of its span
  • so, D = F x S3
    • D = deflection
    • F = force
    • S = span
37
Q

what is the deflection of a bridge with 1 pontic, 2 pontics, and 3 pontics?

A
  • D = F x S3
  • assume F = 1
  • 1 pontic: D = 1 x 13 = 1
  • 2 pontics: D = 1 x 23 = 8
  • 3 pontics: D = 1 x 33 = 27
38
Q

T or F:
a double abutment at the terminal end of a FPD is considered a pier abutment

A
  • false, it is not considered a pier abutment
  • for it to be considered a pier abutment, there must be a pontic separating the two retainers
39
Q

a double abutment is an acceptable method of increasing ___ support for a FPD

A

periodontal

40
Q

every tooth that is included in a fixed bridge increases the vulnerability of ___

A
  • every other tooth that is part of the same bridge
  • what affects one, now affects them all
41
Q

T or F:

when designing FPDs, retrievability is not an important consideration

A

false, it’s definitely important

42
Q

a ___ is an artifical tooth replacing a missing natural tooth that is designed to restore function and appearance

A

pontic

43
Q

what are 5 pontic types?

A
  • sanitary/hygienic
  • saddle/ridge-lap
  • conical/bullet
  • modified ridge-lap
  • ovate/socketed
44
Q

what type of pontic is this?

A

sanitary/hygienic

45
Q

what type of pontic is this?

A

saddle ridge-lap

46
Q

what type of pontic is this?

A

conical

47
Q

what type of pontic is this?

A

modified ridge-lap

48
Q

what type of pontic is this?

A

ovate

49
Q

what is the minimum clearance for a sanitary/hygienic pontic?

A

2mm

50
Q

in the modified ridge lap, the area that contacts tissues resembles what letter?

A

T

51
Q

put the following pontic designs in descending order of strength

A

strength is based on cross-sectional diameter of the metal substructure

52
Q

which of the following is the correct design?

A
53
Q

how can pontics be adjusted to create the illusion of being smaller or larger?

A
  • line angles can be adjusted
  • this can be applied to any prosthesis, retainer, crown, or pontic
54
Q

positioning the ___ can help to create a width illusion

A
  • buccal occluso-gingival height of contour
  • this applies to any prosthesis, retainer, crown, or pontic
55
Q

what are 4 types of connectors?

A
  • cast metal connector
  • soldered connector
  • ceramic connector
  • nonrigid connector (keyway or mortise and tenon)
56
Q

put the following connectors in order of decreasing strength: soldered metal, all ceramic (zirconia, lithium disilicate, cast metal)

A

cast metal > soldered metal > all ceramic

57
Q

T or F:

connectors with larger dimensions have less strength than smaller connectors

A

false

58
Q

how do you calculate the area of a circular connector?

A

πr2

59
Q

how do you calculate the area of a elliptical connector?

A
  • abπ
    • a = radius of long side
    • b = radius of short side
60
Q

between a connector with a longer BL width versus a longer occluso-gingival width, which will best resist occlusal loading?

A

the one with a longer occluso-gingival width

61
Q

what are the minimum recommended cross-sectional dimensions for 3-unit posterior connectors for cast metal, solder, and ceramic (zirconia vs lithium disilicate)?

A
  • cast metal = 6mm2
  • solder = 9mm2
  • zirconia = 9mm2
  • lithium disilicate = 16mm2 (this is too big for more applications)
62
Q

where is the connector position?

A
63
Q

what are 3 nonrigid connector designs?

A
  • keyway
  • mortise and tenon
  • male and female
64
Q

what are 6 most common reasons for bridge failures?

A
  • fractured porcelain
  • recurrent caries
  • loosened single retainer
  • fracture abutment
  • connector failure
  • excessive gap formation between pontic(s) and the edentulous ridge, especially in the anterior region
65
Q

what are 2 important things to advise your FPD patients?

A
  • everything we do has a life expectancy
  • even under the best of circumstances, there will be food traps with either a bridge or an implant
66
Q

many studies demonstrate that shortened dental arches comprising the ___ and ___ regions can meet the requirements of a functional dentition. consequently, when priorities have to be set, restorative therapy should be aimed at preserving these parts of the dental arch

A

anterior and premolar

67
Q

for chewing purposes, the minimum shortening of dental arches should include a pair of ___ in addition to intact ___

A

a pair of occluding molars in addition to intact premolar region

68
Q

oral function is adequate in shortened dental arches comprising of intact ___ and ___ regions

A

anterior and premolar regions

69
Q

T or F:
studies have shown that shortened dental arches often provoke signs and symptoms associated with temporomandibular disorders

A
  • false
  • no evidence was found that SDAs provoked signs and symptoms associated with temporomandibular disorders
  • however, complete absence of posterior support unilaterally or bilaterally appeared to increase the risk for developing signs and symptoms associated temporomandibular disorders
70
Q

extreme SDAs, comprising 0-2 pairs of occluding premolars, had significantly more ___, ___, and ___ compared to intermediate categories of SDAs

A
  • interdental spacing
  • occlusal contact
  • vertical overlap
  • *occlusal wear and tooth mobility were also highest in extreme SDAs
71
Q

satisfactory chewing ability is perceived as long as the dental arch comprises an intact ___ region and ___ occluding pairs of teeth posteriorly

A
  • anterior
  • 3-5
72
Q

SDAs comprising 3-4 occluding pairs of premolars posteriorly did not significantly differ from complete dental arches with regard to ___, ___, ___, and ___

A
  • interdental spacing
  • occlusal tooth wear
  • vertical overbite
  • tooth mobility
73
Q

the risk to occlusal instability seemed to occur in extreme SDAs comprising ___ occluding pairs of teeth whereas no such evidence was found for intermediate categories of SDAs

A

0-2

74
Q

as long as ___ support is present bilaterally, signs and symptoms of temporomandibular disorders are unlikely to manifest themselves. increased risk was only found when ___

A
  • premolar
  • increased risk was only found when all posterior support was unilaterally or bilaterally absent
75
Q

how many occluding units denotes a severely compromised SDA? what about adequate SDA? functional SDA?

A
  • 0-2 OU is severely compromised and likely to continue deteriorating
  • 3-4 OU is often adequate
  • 5+ OU, though not ideal, is often very functional
76
Q

what are 6 contraindications to shortened dental arches?

A
  • marked dento-alveolar malrelationship - severe angle class II or III relationship
  • parafunction - intensive bruxism
  • pre-existing TMD
  • advanced pathological tooth wear
  • advanced periodontal disease - marked reduction in alveolar bone support
  • patient under age 40
77
Q

the survival of 3-unit tooth supported fixed dental prostheses and implant supported single crowns over 15 years was not statistically different when replacing ___ teeth, but implant supported single crowns survived significantly better when replacing ___ teeth

A

posterior, anterior

78
Q

T or F:

removable, fixed, fixed-removable, and implant-supported prostheses all produced significant improvement in oral health related quality of life

A

true

79
Q

among patients treated with removable, fixed, fixed-removable, and implant-supported prostheses, the least amount of improvement was observed in patients with ___

A

removable dental prostheses

80
Q

among patients treated with removable, fixed, fixed-removable, and implant-supported prostheses, oral health related quality of life was comparable between which two?

A

FPDs and implant-supported fixed prostheses

81
Q

among patients treated with removable, fixed, fixed-removable, and implant-supported prostheses, the same treatment can have different impacts on the oral health related quality of life of partially edentulous individuals depending on their ___ and ___

A

age and kennedy classification

82
Q

what are the ideal reduction measurements for an anterior bridge preparation?

A
  • facial depth at margin = 1.2-1.7mm
    • use two-plane facial reduction
  • lingual depth at margin = 0.5-1.0mm
  • incisal reduction = 2.0-2.5mm
    • incisal edge should be perpendicular to the long axis of the tooth
  • lingual concavity depth = 1.0-1.5mm
  • softened line and point angles
83
Q

how much clearance do you want between opposing teeth when prepping a tooth for a bridge?

A

1.0-1.5mm

84
Q

T or F:
when taking a bite registration, you only want to inject the impression material over the prepared teeth

A

true

85
Q

once trimmed, the bite registration should not contact what?

A
  • soft tissue
  • occluding surfaces of teeth not diretly involved with the preparations
86
Q

when curing a temporary bridge, what order should you cure it?

A
  • pontic area first, then move to retainer teeth
  • after removing the temporary, cure the intaglio surface
87
Q

T or F:
triad material bonds to composite resin foundation materials

A

true

88
Q

proper embrasure form of temporary bridges enhances what 3 things?

A

esthetics, cleansability, and gingival health

89
Q

custom tray material should extend ___mm onto soft tissue when possible

A

5-10mm

90
Q

the custom tray handle should attach at ___ degrees at the incisal edge

A

45-60 degrees

91
Q

when curing the custom tray in the triad machine, it should initially cure for ___ minutes, then the tray should be removed from the model/wax, then cured again for ___ minutes per side

A
  • 1 minute
  • 4 minutes per side
92
Q

what are the 4 advantages of custom trays for fixed prosthodontics?

A
  • comfortable for patient
  • stiff and unbendable
  • less impression material
  • consistent accuracy
93
Q

what are the indications for a custom tray?

A
  • 3+ units
  • bridges
  • removable partial dentures
  • implants
94
Q

what are the advantages of rigid stock trays?

A
  • less time intensive
  • variety of sizes
  • customizable
95
Q

what are the disadvantages of rigid stock trays?

A
  • requires more impression material
  • requires more time chairside if not made, pre-clinically, from patient’s cast