Fall Lecture: Pulp protection Therapy: Sealers, Liners, and Bases Flashcards
1
Q
Pulp protection therapy:
A
tx that maintains pulp tissue in healthy and functional state whenever pulp has been exposed by caries, trauma, or restorative procedures
2
Q
3 types of pulpal irritants:
A
microbial, mechanical, chemical
3
Q
Ex’s of microbial irritants:
A
dental caries, perio disease
4
Q
Ex’s of mechanical or physical irritants:
A
incorrectly ortho tx, drilling, periodontal curettage
5
Q
Degree of pulpal reaction depends upon:
A
friction and desiccation
6
Q
Frictional heat from tooth prep can lead to:
A
burn lesions, abscess
7
Q
Chemical irritants that can damage pulp:
A
filling materials, medicines to desensitize, dehyrate, or sterilize dentin
8
Q
Goal of pulp protection therapy:
A
thermal, mechanical, chemical and electrical protection, sealling of dentinal tubules
9
Q
Characteristics of ideal pulp protecting agent:
A
bio/chem compatible, non-permeable barrier on cut dentin, no effect on bulk or mech props of resto, no discoloration of tooth or resto material, sets fast enough for final resto to be completed quickly enough, low solubility in oral “builds”, ease of use during mixing and insertion
10
Q
This provides the best pulpal protection:
A
dentin
11
Q
Thickness of dentin to provide more than 90% of pulpal protection:
A
2mm +
12
Q
Thickness of dentin to provide 90% of pulpal protection:
A
1mm
13
Q
Thickness of dentin to provide 75% of pulpal protection:
A
0.5mm
14
Q
Greatest damage to pulp will result in remaining dentinal thickness (RDT) of:
A
0.25 to 0.3mm
15
Q
When to use sealers, liners, and bases:
A
moderate carious lesion
16
Q
When to use pulp capping, either direct or indirect:
A
deep carious lesion
17
Q
Cavity selares provide:
A
protective coating, leakage barrier
18
Q
2 types of sealers:
A
varnishes and adhesive sealers
19
Q
Varnish:
A
natural rosin or copal gum or synthetic resin, dissolved in organic solvent, acetone, chloroform, or ether
20
Q
Adhesive sealers provide:
A
sealing and bonding
21
Q
Solid component of varnish:
A
copal resin
22
Q
Solvent component of varnish:
A
ether, acetone, alcohol
23
Q
Indications for varnish:
A
Under amalgam: all walls and margins, prevents sensitivity and discoloration, zinc phosphate cement: pulpal flood, prevent acid penetration
24
Q
Contraindications of varnish:
A
under GIC: no thermal protection, prevents adhesion to tooth, under resin restos, residual monomer will dissolve varnish, water soluble
25
Adhesive sealers:
multi-substrate bonding, bonds resto to tooth
26
Ex's of adhesive sealers:
adhesive bonding agents, glass ionomers, resin luting cements
27
indications for use of adhesive sealers:
treat/prevent hypersensitivity, seal dentinal tubules, under all indirect restorations
28
Types of liners:
cement or resin
29
how thick are liners?
usually less than 0.5mm
30
Function of liners:
barrier to bacteria/ byproducts, therapeutic effect, such as antibacterial or pulpal anodyne (pain relieving) effect, fluoride release
31
Walls of prep to which liners are applied:
pulpal floor only
32
4 types of liners:
CaOH2, ZOE, glass ionomer Type 3, flowable composite
33
Base:
goes over liner (check)
34
2 types of calcium hydroxide cements::
self or light curing
35
Which has better mechanical props. light or self curing?
light, VLC dycal, polyphenolics
36
Advantages of CaOH2:
activates ATPse leading to dentin mineralization, stimulates reparative dentin *formation, biocompatible, pH of 12.5, neutralizes acidity/ bacterialcidal
37
Disadvantages to CaOH2
low stegnth, high solubility, dissolves rapidly
38
Function of glass ionome over the CaH2 liner:
support resto
39
Type I glass ionomer:
luting cement
40
Type II glass ionomer:
Restoration
41
Type III glass ionomer:
Liners and Bases
42
Type IV glass ionomer:
Fissure sealants
43
Type V glass ionomer:
ortho cements
44
Type VI glass ionomer:
Core builup
45
List the 6 types of glass ionomers:
luting, restos, liners and bases, fissure sealant, ortho cement, core buildup
46
Glass ionomer type used for pulp protection:
type 3, powder:aluminum silicate glass, liquid: polyalkenote acid, light cure resin
47
Best option for composite restos:
GIC
48
Advantages of GI Type III:
adhesive to tooth, anticariogenic, semi translucent, fluoride release
49
DisAdvantages of GI Type III:
water sorption causes leakage and discoloration, low wear or abrasion resistance
50
Composites with lower filler content:
flowable
51
Properties of flowable composite:
more fluid, less strength, less stiffness
52
What is a base?
replace missing dentin, used for bulk and/or for blocking out undercuts in preps for indirect restorations.
53
Usual thickness for base:
0.5 to 1mm
54
Classifications of bass:
high and low strength
55
High strength bases:
zinc phosphate, zinc polycarboxilate, glass ionomer (type III), reinforced ZOE
56
Low strength bases:
CaOH2, ZOE
57
Functions of a base:
chem insulator, thermal insulator at 0.75mm thickness, mechanical support to resto, distributes stress to underlying dentin
58
oldest luting cement:
zinc phosphate
59
Gold (?) standard to which newer cements are compared:
zinc phosphate
60
Advantages to zinc phosphate:
good mechanical props, thermail insulation
61
Disadvantages to zinc phosphate
does not adhere to tooth structure, exothermic reaction at initial setting that can damage pulp, opaque, not esthetic, dissolves in OC, acidic in nature
62
Composition of powder portion of reinforced ZOE:
zinc oxide and natural or synthetic resin
63
Composition of liquid portion of reinforced ZOE:
eugenol, acetic acid, thymol
64
Props of ZOE:
stronger than regular zinc oxide cements, less pulpal irritation, anodyne effect on pul[
65
When to remove sound tooth structure to provide space for base,
never
66
Benefits of maintaining sound dentin:
better support and pulpal protection
67
Uses of bases for indirect restos:
build up and block out materials for cementing indirect restos
68
What to be aware of when using base under amalgam or resin restos:
minimize extent of base
69
How much liner to use:
minimum thickness to achieve desired result
70
Pulp protection therapy to use when there is more than 2mm dentin thickness for amalgam resto:
varnish
71
Pulp protection therapy to use when there is more than 2mm dentin thickness for composite resto:
dentin bonding agent
72
Pulp protection therapy to use when there is more than 2mm dentin thickness for glass ionomer resto:
none
73
Pulp protection therapy to use when there is more than 2mm dentin thickness for cast gold resto:
none
74
Pulp protection therapy to use when there is 0.5mm-2mm dentin thickness for amalgam resto:
base
75
Pulp protection therapy to use when there is 0.5mm-2mm dentin thickness for composite resto:
dentin bonding agent
76
Pulp protection therapy to use when there is 0.5mm-2mm dentin thickness for glass ionomer resto:
none
77
Pulp protection therapy to use when there is 0.5mm-2mm dentin thickness for cast gold resto:
base
78
Pulp protection therapy to use when there is less than 0.5mm dentin thickness for amalgam resto:
CaOH2 and GIC
79
Pulp protection therapy to use when there is less than 0.5mm dentin thickness for composite resto:
CaOH2 and GIC
80
Pulp protection therapy to use when there is less than 0.5mm dentin thickness for glass ionomer resto:
CaOH2
81
Pulp protection therapy to use when there is less than 0.5mm dentin thickness for cast gold resto:
CaOH2 + base
82
TF? both direct and indirect pulp capping use the same 3 layers: CaOH2, GI, and resto material.
T
83
indirect pulp capping;
not DIRECTLY touching pulp
84
direct pulp capping:
direct contact with inner pulp
85
Pulp capping can be done if:
vital pulp, no spontaneous pain, hot/cold pulp testing pain does not linger after stimulus removal, PA with no evidince of periradicualr lesion, bacteria excluded from a site by the resto
86
2 major factors affect pulpal response to irritants:
rate of caries attack, pulp vitalty
87
This type of lesion forms more reactionary/ tertiary dentin:
small or slowly progressing
88
This type of lesion leads to inflammation or necroses;
rapidly progressing
89
Which forms more reactionary dentin and why, young or old?
Young, more blood supply
90
3 defense reactions of pulp:
tubular sclerosis, tertiary reparative (osteo) dentin formation, pulp inflammation
91
When will reactionary dentin form after pulpal insult?
mild injury, primary odontoblasts survive
92
Appearance of reactionary dentin:
tubular pattern, resembles primary dentin
93
Tubular sclerosis:
process in which minerals deposited witiin the dentinal tubules, reducing the permeability to bacteria and toxic products
94
When is 3' dentin formed:
response to various irritants, ie trauma or caries
95
Where is 3' dentin formed?
dentin/pulp interface, area directly beneath stimulus
96
How does 3' dentin provide extra protection to pulp?
by increasing the distance bw them and injurious stimuli
97
Direct pulp capping:
small pulpal exposure, sound surrounding dentin, dressed with appropriate biocompatible radiopaque base in contact w exposed pulp tissue prior to placing a final reso
98
Goals of direct pulp capping:
pulp vitality and function, normal response to electrical and thermal stimuli, formation of 2'/reparative dentin (check), no prolonged post-op pain or swelling, no pathological changes
99
indications of direct pulp capping:
easily controlled/light bleeding that can be stopped by cotton pellet, traumatic exposure in a dry, clean field, reported to dentist w/in 24h, small pin point exposure surrounded by sound dentin during mech prep of cavity
100
Contraindications for direct pulp capping:
systemic disease (diabetes, cancer), primary teeth w root resorption, pre-op tooth sensitivity, large pulp exposure, Rg changes, uncontrolled bleeding, non restorable tooth or restorable with low prognosis, tooth mobility, swelling and fistula
101
Direct capping px:
lidocaine, isolate, remove decay, pinpoint exposure then, control bleeding with saline, chlorhexidine, or HOO2, gently fry, CaOH2 directly on exposed pulp, GIC liner, restore w composite or amalgam, 6wk follow up
102
Inner "affected" dentin:
few bacteria, remineralizable, intermittently demineralized, vital, sensitive, can be left unexcavated (basis of indirect pulp capping)
103
Outer "infected" dentin:
bacterial invasion, unmineralizable, dead, wo sensation, highly demineralized, superficial layer, deteriorated collagen fibers, should be excavated
104
Goals of indirect pulp capping:
resto mat should seal involved dentin from OC, vitality of tooth preserved, no post-op pain and swelling, no 3' o reparative dentin should be evident on RG after 6 to 12 wks, no evidence of internal resorption
105
Indications of indirect pulp capping:
minimal pulpal inflammation, complete removal of caries would lead to pulp exposure, mild pain assoc with eating, no spontaneous, extreme pain, no mobility, no PA radiolucency
106
Contraindications of indirect pulp capping:
pulpal or PA pathology, soft, leathery dentin covering all area of cavity, pain lingering after removal of stimulus, mobility, discoloration
107
Clinical px for indirect pulp capping:
lidocaine, isolation, cavity outline with high speed, remove superficial debris and most soft necrotic dentin (infected) w slow speed and round bur, caries dye, leave hard, leathery dentin, rinse with saline, gently air dry, CaOH2 cement on deepest position of prep, liner covered with GIC and final resto done (amal or comp), 6wk rg follow-up to check for reparative dentin formation
108
Multi-visit indirect pulp capping px:
after CaOH2 liner and cement, interim resto, after 6wk RG exam for reparative dentin formation, lidocaine, isolation, re-enter remove remaining caries, place final resto
109
6 pulp capping materials:
ZOE, CaOH2, MTA (mineral trioxide aggregate), glass ionomer, resin modified glass ionomer, adhesive systems
110
Props of ZOE cements:
germicidal, palliative, tight initial seal, arrest caries process
111
Affect of CaOH2 on bacteria:
initially bactericidal then static
112
Does CaOH2 stimulate reparative dentin?
yes
113
CaOH2, high or low toxicity?
low
114
Effect of CaOH2 on internal resorption:
stops it
115
Contraindications fr CaO2:
does not bond to tooth, degrades acid etching, not enough mech strength to withstand condensation pressure under amal resto, dissolves in oral "builds" (fluids?)
116
Indications for mineral trioxide aggregate:
adheres to tooth, stimulates reparative dentin better and faster than CaOH2, biocompatible, low cytotoxicity, better marginal seal, good mech strength, antibacterial
117
Contraindications for MTA:
gray color, 2 to 4 hr setting time, expensive, high solubility
118
Benefits of GIC:
better bacterial seal, fluoride release chem bond to tooth and resin cement
119
Props of adhesive systems:
complete marginal seal, prevents bacterial invasion, allows pulp repair
