Obturation Flashcards
1
Q
Who introduced gutta percha as a filling material?
A
Bowman
2
Q
Who introduced silver points as a filling material and when?
A
Trebitsch 1929
3
Q
Who listed the ten properties of a good root canal cement?
A
Grossman 1958
4
Q
Who created what is now tubli-seal?
A
Grossman
5
Q
Who first introduced warm vertical condensation?
A
Schilder 1967
6
Q
Describe Schilder’s technique for vertical condensation
A
Master apical cone placed, “spreaders” remove all but the last 3-5 mm, the 2-4 mm plugs of heated gutta percha are condensed with pluggers that get incrementally larger in size.
7
Q
Who found that gutta percha is less compressible than water?
A
Schilder and Goodman
8
Q
Schilder and Goodman found that gutta percha is _______ not _________
A
compactable not compressible
9
Q
Who demonstrated dye penetration after condensation with all known techniques unless cementing agent was used? (ie gutta percha cannot seal by itself)
A
Schilder
10
Q
According to ______, the reduction in apparent volume during condensation is due to what?
A
Schilder, Consolidation and collapse of internal voids.
11
Q
color of gutta percha
A
yellowish brown
12
Q
What is gutta percha? Where does it come from?
A
a naturally occuring polymer of isoprene. The Taban tree
13
Q
Difference between gutta-percha and rubber?
A
They are isomers:
Rubber: CH2 groups are on same side (cis).
Gutta percha: CH2 groups are on opposite sides (trans)
14
Q
Three differences in properties of gutta percha and rubber?
Why?
A
Gutta percha is harder, more brittle, and less elastic (b/c it’s trans, so CH2 groups are on opposite sides, which makes the polymer more linear so it crystalizes more easily)
15
Q
Who found that gutta percha could exist in two different forms? Called them?
A
CH Bunn alpha and beta
16
Q
Which type of gutta percha has a lower melting point?
A
beta
17
Q
No difference in ______ properties of alpha and beta gutta percha, but there are ______ and ______ differences
A
mechanical,
thermal and volumetric
18
Q
Phase transitions of gutta percha as heated? Says who?
A
beta to alpha 42 to 49 degrees celcius
alpha to amorphous 53 to 59 degrees celcius
schilder
19
Q
Largest component of dental gutta-percha?
A
zinc oxide
20
Q
3 fold test for a good root canal cement?
A
offers some resistance to spatulation
doesn’t drop off the spatula in 12 to 15 seconds when held vertically
strings out for 2.5 cm before breaking
21
Q
who said no correlation between particle size and flow rate in root canal cements?
A
Goodman
22
Q
component of root canal cement that accelerates set? Retards set?
A
accelerates: bismuth subnitrate
retards: sodium borate
23
Q
Who introduced injectable gutta percha as an obturation technique (did in vitro)? When?
A
Yee 1977
24
Q
What obturation technique did Yee say in his 1977 study is a viable obturation method?
A
Injection technique
25
Who showed that leakage is the same for injectable v. warm vertical v. lateral condensation?
Yee 1977?
26
Who first introduced the carrier technique for obturation? when? what was the carrier?
Ben Johnson 1978 the master apical file with coronal flutes removed
27
What obturation technique did Ben Johnson introduce in 1978?
Carrier based.
28
Who said use at least 3.5 mm of cavit to prevent leakage of temporary restoration?
Webber 78
29
What is cavit?
A zinc oxide and polyvinyl preparation
30
Webber 78, recommendation for temporary restorations?
cavit should be at least 3.5 mm thick to prevent leakage
31
Who studied peripaical inflammation in monkeys treated with sargenti's paste?
Carl Newton 1980
32
Findings of Carl Newton's Sargenti paste study 1980?
Teeth with pulpitis had no periapical inflammation. Teeth with necrosis, or treated with sargenti's paste, did have periapical inflammation.
33
Ng 2008 said what four factors influence rct success?
absence of pretx periapical lesion, no voids, obturation to within 2 mm of apex, adequate coronal restoration
34
Who said from their meta analysis that the four factors that influence root canal success are absence of pretx periapical lesion, no voids, obturation to within 2 mm of apex, adequate coronal restoration
Ng 2008
35
Who said the maximum temp range of gutta percha during warm condensation is 80 degrees, and 40 to 42 in the apical region.
Goodman and Schilder 1981
36
Who said thermal penetration of gutta percha is limited to 4-6 mm into the material from point of entry, or 2-3 mm from point of deepest penetration?
Goodman and Schilder 1981
37
What did Goodman and Schilder 1981 say about how much heat penetrates during WVC?
4-6 mm from point of entry into gutta percha, or 2-3 mm from point of deepest penetration
38
According to Goodman and Schilder 1981, what is the maximum temperature in the body of the canal during WVC? In the apical region?
80 degrees celcius; 40-42 degrees celcius
39
Allison 1981
master cone adaptation?
Master cone adaptation as assessed by radiographic criteria did not affect the quality of the apical seal when cones were fitted to within 1 mm of the preparation, and had tugback
40
Who said as long as the master cone is fitted to within 1 mm of the preparation and has tug back, it will be adequately sealed at the apex?
Allison 1981
41
Swanson and Madison 1987
| if temp is lost?
According to an in vitro study, If a temporary is lost, there will be coronal micro leakage into the obturation material within three days of exposure to saliva.
42
Who said, according to an in vitro study, If a temporary is lost, there will be coronal micro leakage into the obturation material within three days of exposure to saliva. (and it's no greater after 8 weeks)
Swanson and Madison 1987
43
Who found that AH26 sealer demonstrated significantly more coronal micro leakage than either Sealapex or Roth's sealers? (In vitro)
Madison and Swanson 1987
44
Who found that in vivo, there is no significant difference in micro leakage among sealers exposed to the oral environment for one week?
Madison 1988
45
Results of Madison's two (87,88) studies on leakage and sealers?
In artificial saliva, AH26 demonstrated more leakage. In monkeys, no difference in leakage among sealers exposed to the oral environment for one week.
46
Who said IRM leaks after thermal cycling, and Cavit is not good for complex restorations. Recommends TERM?
Anderson and Pashley 1989
47
Anderson and Pashley 1989
temporary restoration?
IRM leaks after thermal cycling, and Cavit is not good for complex restorations . TERM is best, but even it leaks after several weeks.
48
According to Anderson and Pashley, why is Cavit not good for complex restorations?
(high thermal expansion and no walls to confine it leads to cracking) also low compressive strength contributes to deterioration.
49
Bobotis, Anderson, Pashley 1989
temporary restorations?
In standard endodontic preparations, all temporary materials demonstrate similar leakage, except polycarboxylate cement, and IRM (after thermal cycling)
50
Who said In standard endodontic preparations, all temporary materials demonstrate similar leakage, except polycarboxylate cement, and IRM (after thermal cycling)
Bobotis, Anderson, Pashley 1989
51
Who questioned the validity of all our in vitro leakage studies, advocating that more research should be done on leakage study methodology, plus we don't even know if leakage causes PA inflammation?
Wu and Wesselink 1993
52
Wu and Wesselink 1993
leakage studies?
questioned the validity of all our in vitro leakage studies, advocating that more research should be done on leakage study methodology, plus we don't even really know if leakage causes PA inflammation?
53
According to Wu and Wesselink, problems with leakage studies?
leakage studies provide semi-quantitative data, choice of tracers might not correspond to molecules we're worried about, pH could make a difference, there might be entrapped air. We don't have in vivo studies to confirm in vitro studies--the quantitative relationship b/n leakage of bacterial products out of RCT and periodical inflammation should be determined.
54
Who said treatment with EDTA significantly reduces extent of residual calcium hydroxide?
Margelos 1997
55
Who found that calcium hydroxide interacts with eugenol, inhibiting Zinc Oxide eugenol chelate formation (which leads to residual eugenol in set product, and brittle granular sealer)
Margelos 1997
56
Margelos 1997
What removes calcium hydroxide best?
Who said treatment with EDTA significantly reduces extent of residual calcium hydroxide?
57
Margelos 1997
why is it important to remove CaOH?
found that calcium hydroxide interacts with eugenol, inhibiting Zinc Oxide eugenol chelate formation (which leads to residual eugenol in set product, and brittle granular sealer)
58
Lee 1998
Showed that condensation with system B should not damage supporting periradicular tissue. (less than 10 degree celcius rise in external root surface temp)
59
who Showed that condensation with system B should not damage supporting periradicular tissue. (less than 10 degree celcius rise in external root surface temp)
Lee 1998
60
Who showed that the poor thermal conductivity of dentin (1.36 x 10-3 cal/sq cm degrees Celcius) will help dissipate heat and prevent its passing through to the periodontal attachment apparatus?
Craig and Peyton 1961
61
Who quantified the critical temperature that causes irreversible bone damage as 10 degrees Celcius on the root surface?
Eriksson and Albrektsson 1983, 1984
62
Eriksson and Albrektsson 1983, 1984
WVC?
quantified the critical temperature that causes irreversible bone damage as 10 degrees Celcius on the root surface
63
Wu and Wesselink 2000
sealer distribution
3 mm from the apex, there is equal sealer distribution b/n lateral and WV condensation. 6 mm from apex, there is more sealer distribution for lateral than vertical condensation. At 3 and 6, there was significantly more sealer with no condensation(single cone).
64
Who said: 3 mm from the apex, there is equal sealer distribution b/n lateral and WV condensation. 6 mm from apex, there is more sealer distribution for lateral than vertical condensation. At 3 and 6, there was significantly more sealer with no condensation(single cone).
Wu and Wesselink 2000
65
Who said more sealer does not always result in a better sealer coverage?
Wu and Wesselink 2000
66
Who said there is no cross reactivity between gutta percha and latex, but there is some cross reactivity with the substitute gutta balata and latex?
Costa 2001
67
Costa 2001
Gutta percha?
Use of gutta percha in individuals sensitive to latex represents a minimal risk.
68
Who showed that in monkeys, if there was no bacteria, healing occurred regardless of quality of obturation?
Moller 2006
69
Moller 2006
bacteria
In monkeys, if there was no bacteria, healing occurred regardless of quality of obturation.
70
Moller 2006
non healing
In monkeys: 28% of teeth with no bacteria after cleaning and shaping didn't heal
70% of teeth with bacteria after cleaning and shaping didn't heal
71
who said the criteria of clean dentinal filings and/or enlargement beyond first file to bind at WL were unreliable determinants of whether canal was effectively cleaned?
Walton 76
72
Walton 76
determinants of whether a canal is effectively cleaned?
the criteria of clean dentinal filings and/or enlargement beyond first file to bind at WL are unreliable determinants of whether canal was effectively cleaned
73
Who reported that good postendodontic restorations resulted in significantly more successful cases when compared to good endodontics (80 v. 75.7%)?
Ray and Trope 1995
74
Ray and Trope 1995
importance of good post endo restoration
Good postendodontic restoration = more successful cases compared to good endodontics (80 v. 75.7%)
75
Aquilino and Caplan 2002
post endo restoration
The prognosis for endodontically treated posterior teeth restored with crowns is enhanced sixfold.
76
Who showed The prognosis for endodontically treated posterior teeth restored with crowns is enhanced sixfold.
Aquilino and Caplan 2002
77
Who showed that coronal leakage was not a significant factor in root canal failure?
Ricucci and Bergenholtz 2000, 2003
78
Who said an adequate radiographic appearance of obturation may not correlate with an adequate seal?
Ebert 96
79
Who developed the first root canal filling material? When?
Hill 1847
80
When were gutta percha points first manufactured?
1887 by S.S. White Company
81
Who showed that 94% of cases that yielded a negative culture prior to obturation healed completely, while only 68% of cases that yielded a positive culture healed completely?
Sjogren 1997
82
Sjogren 1997
evidence for two visits better than one?
showed that 94% of cases that yielded a negative culture prior to obturation healed completely, while only 68% of cases that yielded a positive culture healed completely
83
Peters, Wesselink 2002
evidence that one visit is ok?
Complete radiographic healing occurred in 81% of one visit cases, and 71% of two visit cases.
84
Penesis 2008
evidence that one visit is ok?
NSD in success at 12 mos. in 63 patients (one visit v. two visits)
85
Molander 2007
evidence that one visit is ok?
NSD in healing between one and two visit tis, however negative cultures at obturation = 80% success, positive cultures = 44% success
86
Weiger 2000
evidence that one visit is ok?
Two visits with calcium hydroxide did not produce a significant difference in periodical healing compared to one visit
87
Katebahzedeh and Trope 2000
evidence that two visits is better than one?
Calcium hydroxide treated teeth had fewer failed cases ( 15.8% v. 41.2%) and more improved cases (47.4% v. 23.5%)
88
Holland 2001
evidence that two visits is better than one
2 visits showed better healing periodical healing than one, and the 14 day calcium hydroxide group is better than 7 days
89
Who says 14 days of CaOH2 interappointment is better than 7?
Holland, DeSouza, Murata 2001
90
Bystrom, Sundqvist 1981
why use calcium hydroxide?
Bacteria in instrumented, unfilled canals can multiply and reach pretreatment numbers in 2-4 days.
91
Who said Bacteria in instrumented, unfilled canals can multiply and reach pretreatment numbers in 2-4 days.
Bystrom, Sundqvist 1981
92
Who showed that the main molecules present in MTA are calcium and phosphorous ions. In addition, MTA has a pH of 10.2 initially, which rises to 12.5 three hours after mixing
Torbinejad, Pitt-Ford 1995
93
Torbinejad, Pitt-Ford 1995
| Showed two things about ____
MTA:
The main molecules present are calcium and phosphorous ions. Initial pH is 10.2, rises to 12.5 three hours after mixing.
94
who created the system B pluggers (tips)? What did he use them for?
Buchanan. Continuous wave obturation. (as in continuous wave of heat.)
95
who showed in an in-vitro study that exposure of coronal gp to bacterial contamination can lead to migration of bacteria to the apex in a matter of days.
Swanson, Madison 1987
96
Who said that bacterial byproducts and endotoxins can penetrate to the apex in an even shorter time than bacteria
Alves 1998
97
Alves 1998
| bacterial penetration
bacterial byproducts and endotoxins can penetrate to the apex in an even shorter time than bacteria
98
Who demonstrated that in vitro there is less bacterial penetration of endodontically treated teeth that are coronally sealed with a dentin bonding agent?
Wolanek 2001
99
Wolanek 2001
demonstrated that in vitro there is less bacterial penetration of endodontically treated teeth that are coronally sealed with a dentin bonding agent
100
study to support using a dentin bonding agent to seal the canals?
Wolanek 2001
101
who showed that use of a eugenol based sealer does not affect the ability of a dentin bonding agent to seal the canals?
Wolanek 2001
102
Who showed that 3 mm of gutta-percha provides an unreliable apical seal, therefore 4-5 mm is recommended be retained during post space preparation?
Abramovitz 2001
103
Abramovitz 2001
3 mm of gutta-percha provides an unreliable apical seal, therefore 4-5 mm is recommended be retained during post space preparation
104
Varela 2003
| cementing in posts?
Concerns about negative effects of sodium hypochlorite irrigants on resin adhesion to dentin are unfounded
105
Who said Concerns about negative effects of sodium hypochlorite irrigants on resin adhesion to dentin are unfounded
Varela 2003
106
Who said that resin adhesion to dentin on the pulpal floor is generally not as strong or reliable as to coronal dentin?
Kijsamanmith 2002
107
Kijsamanmith 2002
resin adhesion to dentin on the pulpal floor is generally not as strong or reliable as to coronal dentin?
108
Who said that, due to morphological differences in radicular dentin (reduction of dentinal tubule density and altered collagen expression), adhesion is more problematic in apical dentin compared with coronal dentin?
Mjor 2001
109
Mjor 2001
due to morphological differences in radicular dentin (reduction of dentinal tubule density and altered collagen expression), adhesion is more problematic in apical dentin compared with coronal dentin
110
Collins and Kulild 2006
warm vertical is better than cold lateral at defect replication
111
Who said that warm vertical is better than cold lateral at defect replication?
Collins and Kulild 2006
112
Who showed that Roth sealer shows greater antimicrobial activity than calcium hydroxide sealers?
Mickel and Wright 1999
113
Mickel and Wright 1999 sealer?
Roth sealer shows greater antimicrobial activity than calcium hydroxide sealers.
114
Who said that lack of post-treatment disease is related to an obturation 0-2 mm from apex?
Wu and Wesselink 2012
115
Wu and Wesselink 2012 how long to obturate?
Lack of post-treatment disease is related to obturation 0-2 mm from the apex.
116
Who presented a case of nerve paresthesia caused by sealer in the IAN, and did a literature review that surgical removal of sealer from IAN helps prevent permanent damage?
Gonzalez-Martin 2010
117
Brown 1994 (sealer)
Sealer (Roth or glass ionomer) significantly improves the apical leakage of laterally condensed gutta percha (in vitro)
118
Who showed that sealer (Roth or glass ionomer) significantly improves the apical leakage of laterally condensed gutta percha (in vitro).
Brown 1994
119
Who said that best result is to obturate at the apical constriction (0.5 to 2 mm short of the radiographic apex)?
Ricucci 1998
