- Email: [email protected]
Retentive properties of a threaded split post with attachment sleeves cemented with various luting agents
Retentive properties of a threaded split post with sleeves cemented with various luting agents Brett I. Cohen, PhD,= Spyridon Condos, DDS,b Allan Barry Lee Musikant, DMDC Essential Dental Laboratories, S. Hackensack, N. J.
S. Deutsch,
DMD,C
attachment
and
This study determined the retention, in pounds, of Nos. 1 through 3 stainless steel attachment sleeves for the threaded split post system cemented with various cements. Post heads and matching sleeves were also sandblasted and compared with attachments not sandblasted. Four luting agents were selected, zinc oxyphosphate cement (ZOP), and three brands of composite resin cement (CRC). The experiment was divided into two parts; in part 1, samples were not treated, and in part 2, samples were sandblasted. Retentive values were recorded with a universal three-way analysis of variance was used to testing machine. A 2 x 3 x 4 factorial compute the effects sandblasting, sleeve and post type, and the luting agent. No statistical differences were recorded for sleeves not sandblasted, Nos. 1 and 2, regardless of the luting agent. The nonsandblasted No. 3 sleeve cemented with Panavia CRC had significantly greater retention than All-Bond CRC or ZOP. There were no statistical differences in retention of sandblasted sleeves for the No. 1 sleeve despite the type of luting agent. For sandblasted sleeves Nos. 2 and 3, ZOP and Panavia CRC recorded significantly greater retention than All-Bond CRC. However, there was no difference between sandblasting and not sandblasting for the No. 1 sleeve. Mean loads for Nos. 2 and 3 sleeves were substantially greater for sandblasted compared with attachments not sandblasted. (J PROSTHET DENT 1993;69:149-54.)
R
etention of an artificial crown to tooth structure or core material is critical for a successfulrestoration. A predictable, uncomplicated technique that provides retention of the crown to tooth structure will be welcomed.The Flexi-Cast crown/core system (Essential Dental Systems, S. Hackensack, N. J.) combinesa prefabricated post with a contiguous head and a precision attachment sleeve.The attachment sleeve is then incorporated in the finished artificial crown. The shaft portion of Flexi-Cast System is a prefabricated, highly retentive threaded split post, similar to the Flexi-Post dowel (Essential Dental Systems).1-5 The machined attachment sleevefor the Flexi-Cast system, constructed from stainlesssteel or titanium alloy, has circumferential groovesthat match circumferential grooves on the prefabricated post head. When the sleeve is cemented to the post head, the alignment of the sleeve grooves and the grooves in the post head results in outstanding retention of the sleeveto the post. The mean values reported for zinc oxyphosphate (ZOP) cementwithout sandblastingranged from a minimum of 125lb for the No. 1 size cast post to a maximum of 170.5lb for the No. 3 largest cast post.6 Malalignment of approximately 0.56
aVice-President of DentalResearch. bPrivatePractice,NewYork, NY; ClinicalInstructor, NewYork University Collegeof Dentistry. CCo-director of DentalResearch. CopyrightQ 1993by The Editorial Councilof THE JOURNAL OF PROSTHETIC DENTISTRY. 002%3913/93/$1.00 +.lO. FEBRUARY
1993
10/l/42662
Fig. 1. Vise grips of a universal testing machine for the sleevecemented with C & B Metabond CRC to the FlexiCast post head before testing.
mm, or 560 pm, for sleevescemented with ZOP cement without sandblastingto the correspondingcast post head did not causea lossof retention.7 Numerous commercial adhesive luting agents can be usedto cement metal to metal surfaces.Examples are C & B Metabond compositeresin cement (CRC) (Parke11Products, Inc., Farmingdale, N. Y.), All-Bond CRC (Bisco, Inc., Downers Grove, Ill.), and Panavia CRC (J. Morita, Tustin, Calif.). C & B Metabond CRC involves a I-MetalMMA-TBB 149
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Fig.
2. Retentive failure for a Flexi-Cast sleeveand post head cemented (with C&B Metabond CRC, after testing.
Fig.
Table I. Retention of nonsandblastedand sandblasted sleevescemented with zinc oxyphosphate cement
Table III. Retention of nonsandblastedand sandblastedsleevescemented with All-Bond CRC
Sandblasted sleeves and Flexi-Cast post heads, group 4
Non-sandblasted sleeves6 Flexi-Cast sleeve No.
1 2 3
Mean
(lb)
125.8 137.1 170.5
SD 71.9 43.1 58.9
Mean
(lb)
109.7 247.0 260.6
Flexi-Cast sleeve No. 1 2 3
Mean 108.2 136.1 209.1
(lb)
1 SD
SD 34.9 99.0 130.0
1 2 3
37.7 37.0 73.5
Sandblasted sleeves and Flexi-Cast post heads, group 6 Mean 105.1 169.3 220.6
(lb)
SD 22.9 23.6 52.1
chemistry with the 4-Meta systemthat is purported to be hydrophilic and strong bonding for metal to metal surfaces or interfaces.8,g The All-Bond CRC system involves a primer A with NTG-GMA in acetoneand a primer B with BPMA in acetoneincluding an unfilled resin adhesivecontaining a hydrophilic monomer(HEMA).1°-12 Strong metal bondshave alsobeenreported for the All-Bond system.l’*l2 The Panavia CRC system incorporates a cumenehydroperoxide (CHP) initiation system,with monomerspolymerized without oxygen (anaerobic), resulting in strong bonding of metal to metal surfacesand interfaces.s This study determined the retentive values of Nos. 1
150
Non-sandblasted sleeves, group Flexi-Cast sleeve No.
Table II. Retention of nonsandblastedand sandblasted sleevescemented with C & B Metabond CRC Non-sandblasted sleeves, group
3. Enlargement of the cemented sleeve and post head after failure.
Mean
(lb)
157.7 180.4 157.6
2
Sandblasted sleeves and Flexi-Cast post heads, group 6
SD 58.9 39.3 31.8
Mean
(lb)
SD
114.5 128.9 159.6
27.7 37.3 45.5
through 3 stainless steel attachment sleeves that were sandblasted or not sandblastedand cemented with four luting agents.
MATERIAL
AND
METHODS
This experiment was divided in two parts, with seven groups. Part 1 included the retention of cementedattachment sleevesthat were not sandblastedand part 2 examined the retention of sandblastedattachment sleevesand cast post heads. In part 1 of the experiment, a total 90 (30 each for sizes No. 1,2, and 3) attachment sleeves(not sandblasted)were cemented to their corresponding post headswith C & B Metabond CRC (group l), All-Bond CRC (group 2), and Panavia CRC (group 3). All cementation procedures followed the manufacturer’s instructions. In part 2, a total of 120 (40 each for sizesNo. 1, 2, and 3) attachment sleevesand castpost headsweresandblasted and cementedto their correspondingpost headswith zinc oxyphosphate cement (ZOP) (Flecks zinc cement, Mizzy Inc., Cherry Hill, N. J.) (group 4), C & B Metabond CRC (group 5), All-Bond CRC (group 6), and Panavia CRC (group 7). All luting agentsand correspondingcementation proceduresfollowed the manufacturers’ instructions.
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PROPERTIES
WITH
VARIOUS
BONDING
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Pounds 300
250
No. 1
No. 2
No.3
S, No. 1
S, No.2
S, No.3
S = Sandblasted Fig.
4. Retention of Flexi-Cast sleevescemented with ZOP.
Sandblasting for the attachment sleeve and cast post heads was performed with a sandblasting box (Handler Mfg. Co., Inc., Westfield, N. J.) connected to a 1 hp compressor (Speedaire, Dayton, Chicago, Ill.). A 240 mesh aluminum oxide abrasive powder (Ney-Brasive, J. M. Ney Co., Bloomfield, Conn.) was selected and Flexi-Cast post heads and matching sleeves were sandblasted until a roughened surface was evident. Sandblasting was performed for an averageof 2 to 3 minutesto create the desired surface. All cemented attachment sleeves(parts 1 and 2) set for at least 1 hour, and the specimenswere then immersedin 100% humidity for 1 week before tensile testing. Sleeves were subjected to a tensile force (Figs. 1 through 3) on a universal testina machine (Comten Industries, St. Petersburg, Fla.) until failure with a crossheadspeed of 0.25 inches per minute (0.635 cm/minute). This resulted in retentive failure for each attachment sleeve, measured in pounds, and failure was confirmed when the cemented sleevewas removed from the Flexi-Cast post head.
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1999
Table IV. Retention of nonsandblastedand sandblasted sleevescemented with Panavia CRC Non-aaadblasted sleavaa, Group Flexi-Ca8t sleeve No. 1 2 3
STATISTICAL
Mean 136.0 163.2 261.9
(lb)
3 SD 27.0 29.6 64.2
Sandbhsted &eves and Flexl-Cast post Beads, group 7 lean 141.1 195.2 270.0 ----
(lb)
SD
-
24.5 48.4 63.0
METHODS
A 2 X 3 x 4 factorial three-way analysis of variance (ANOVA) was selected to compute the effects of sandblasting, sleeve and post type, and luting agent.13The result was considered statistically significant if p < 0.05.
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Pounds
250
T
200
150
100
50
-I
0 No.1
No.2
No.3
S = Sandblasted Fig.
5. Retention
of Flexi-Cast
I
-t
S, No.1
sleeves cemented
S,No.2
with
S, No.3
C & B Metabond
CRC.
Pounds
No. 1
No.2
No.3
S, No. 1
S,No.2
S, No.3
S = Sandblasted
Fig.
152
6. Retention
of Flexi-Cast
sleeves cemented
with All-Bond
CRC.
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RETENTIVE
PROPERTIES
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BONDING
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Pounds
250
200
150
100
50
0 No.
1
No. 2
No. 3
S, No.1
S, No.2
S, No.3
S = Sandblasted Fig.
7. Retention
of Flexi-Cast
RESULTS Retentive failure was recorded when the cemented sleeve was separated from the cast post head. Tables I-IV summarize sleeves not-sandblasted compared with sandblasted sleeves. Retention improved as the sleeve and the cast post head increased in sizes from No. 1 to No. 3 for all groups. ANOVA revealed that all two-way interactions were significant: (1) interaction of sandblast and sleeve and post number (p < 0.0126); (2) interaction of sandblast and cement (p < 0.0002); and (3) interaction of sleeve and post number and cement (p < 0.0014). There were no statistical differences in retention of sleeves not sandblasted for the Nos. 1 and 2 sleeves despite the type of cement. For the No. 3 nonsandblasted sleeve, Panavia CRC bonding was significantly greater than for All-Bond CRC and ZOP. The data suggested that C & B Metabond CRC retention was greater than that of AllBond CRC, whereas Panavia CRC retention was greater than that of Metabond CRC, but these results were barely statistically significant. For the cements All-Bond CRC and ZOP, there was no difference between the sleeves not sandblasted. For both C
FEBRUARY
1993
sleeves cemented
with Panavia
CRC.
& B Metabond CRC and Panavia CRC, No. 1 and No. 2 sleeves not sandblasted were similar, but each recorded significantly lower mean loads than the No. 3 nonsandblasted sleeve. For the sandblasted sleeve, no statistical difference in retention was observed for No. 1 sleeve despite the luting agent. For sleeve No. 2, ZOP and Panavia CRC had significantly greater retention than All-Bond CRC, with ZOP’s greater than that of C & B Metabond CRC. The data suggested that Panavia CRC retention was greater than that of C & B Metabond CRC, but the result was not statistically significant. The mean loads for ZOP and Panavia CRC for the No. 3 sleeve were significantly greater than for AllBond CRC, with ZOP superior to C (YEB Metabond CRC. The data implied that C & B Metabond CRC retention was greater than that of All-Bond CRC, but this result was also not statistically significant. Within cement groups, no difference was apparent for Nos. 1, 2, and 3 sandblasted sleeves using All-Bond CRC. For C & B Metabond CRC, the No. 3 sandblasted sleeve recorded greater retention than the No. I sandblasted sleeve. The data suggested that the No 2 sandblasted sleeve also had greater retention than that of the No. 1
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sandblasted sleeve, but this result was not statistically significant. For Panavia CRC, Nos. 2 and 3 sandblasted sleeves exhibited greater mean loads than the No. 1 sandblasted sleeves. For ZOP, Nos. 2 and 3 sandblasted sleeves had greater mean loads than the No. 1 sandblasted sleeves. There was no difference recorded for the No. 1 sleeve, sandblasted or not sandblasted. The mean load for Nos. 2 and 3 sleeves was statistically greater for sandblasting, but the significance was borderline. Only ZOP had mean loads for the sandblasted sleeves that were significantly greater than for the attachments not sandblasted. For the three remaining cements of All-Bond CRC, C & B Metabond CRC, and Panavia CRC, there were no significant differences between sandblasting and the type of cement.
DISCUSSION Retentive failure was recorded when the cemented sleeve was dislodged from its corresponding post head. The retention was more than 100 lb in this study regardless of the cement and the sandblasting of the attachments (Figs. 4 through 7). There was no statistical difference between samples without sandblasting despite cements used with the smaller sizes, Nos. 1 and 2, Flexi-Cast post and sleeves. However, when the No. 3 sleeve was tested, Panavia CRC had substantially more retention than All-Bond CRC and ZOP. The elevated retention reported for Panavia CRC was probably because of the greater cohesive strength for the cement compared with All-Bond CRC. All-Bond CRC consistently recorded the lowest values and there was no difference in retention with All-Bond CRC for the Nos. 1, 2, and 3 sleeves. This indicated that the cohesive strength for All-Bond CRC was low between metal interfaces. Sandblasted No. 1 sleeves did not result in a statistical difference with different luting agents. However, when Nos. 2 and 3 sleeves were tested, Panavia CRC and ZOP both had statistically more retention than All-Bond CRC. The greater retention observed for Panavia CRC and ZOP can be attributed to the superior cohesive strength for these cements compared with All-Bond CRC. All-Bond CRC and C & B Metabond CRC consistently recorded the least retention and Panavia CRC and ZOP the greatest. There was no difference in retention for Nos. 1, 2, and 3 sandblasted sleeves with All-Bond CRC. Differences between sandblasting and not sandblasting were recorded only for Nos. 2 and 3 Flexi-Cast sleeves and post head combinations. These two sizes benefited by the sandblasting.
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CONCLUSIONS Two hundred forty Flexi-Cast post heads with their corresponding Flexi-Cast sleeves were cemented with four different luting agents: ZOP, Panavia CRC, All-Bond CRC and C & B Metabond CRC. Half of the samples were also sandblasted. 1. Panavia CRC and ZOP recorded the greatest retention and All-Bond CRC and C & B Metabond CRC exhibited the least. 2. Sandblasting significantly improved the retention for Flexi-Cast sleeves Nos. 2 and 3, compared with sleeve No. 1.
3. The retention for all sizes of Flexi-Cast sleeves and cements exceeded 100 lb for all groups in this study.
Contributing
author
Kongren Jiang, MS, Essential Dental Laboratories Research Engineer and Chemist. REFERENCES
5. 6. I. 8. 9.
10.
11.
12. 13.
Deutech AS, Musikant BL, CavaIlari J, Bemardi S. Retentive properties of a new post and core system. J PROSTHET DENT 1985,53:12-4. Millstein PL, Yu H, Hsu CS, Nathanson D: Effects of cementing on retention of a prefabricated screw post. J PROSTHET DENT 1987;67:171-4. Brown JD, Mitchem JC. Retentive properties of dowel post systems. Oper Dent 1987;12:15-9. Saunders RD, Lorey RE, Powers JM, Sloan KM. Comparison of five post-cement systems for tensile retentive capacity [Abstract]. J Dent Res 1988;67:304. Cohen BI, Mu&ant BL, Deutsch AS. Comparisonof the retentive properties of four post systems. J PROSTHET DENT 1992;68:264-8. Deutsch AS, Cohen BI, Musikant BL. Retentive properties of attachment sleeves for a new cast-post system. J PROSTHET DENT 1992;67:34-6. Cohen BI, Deutsch AS, Musikant BL. Retentive properties of misaligned post attachment sleeves. J PROSTHET DENT 1992;67:191-3. Barzilay I, Vassilas A. Panvia and 4-Meta bond to amalagam and NiCr alloy [Abstract]. J Dent Res 1996;69:363. Imbery TA, Burgess JO, Naylor WP. Tensile strength of resin cements with various alloy surface treatments [Abstracts]. J Dent Res 1991;70:390. DeSchepper EJ, Cailleteau JG, Roeder L, Powers JM. In vitro tensile bond strengths of amalgam to treated dentin. J Esthet Dent 1991;3:11720. Roeder LB, DeSchepper EJ, Powers JM. In vitro bond strength of repaired amalgam with adhesive bonding systems. J Esthet Dent 1991$126-S. Suh BI. All-bond fourth generation dentin bonding system. J Esthet Dent 1991;3:139-47. Zar JH. Biostatisticai analysis. Englewood CIiis, NJ: Prentice-Hall, 1974;151-4.
Reprint
requests
to:
DR. BRETT I. COHEN 89 LEUNING ST. S. HACKENSACK, NJ 07606
VOLUME
69
NUMBER
2
S. Deutsch,
DMD,C
attachment
and
This study determined the retention, in pounds, of Nos. 1 through 3 stainless steel attachment sleeves for the threaded split post system cemented with various cements. Post heads and matching sleeves were also sandblasted and compared with attachments not sandblasted. Four luting agents were selected, zinc oxyphosphate cement (ZOP), and three brands of composite resin cement (CRC). The experiment was divided into two parts; in part 1, samples were not treated, and in part 2, samples were sandblasted. Retentive values were recorded with a universal three-way analysis of variance was used to testing machine. A 2 x 3 x 4 factorial compute the effects sandblasting, sleeve and post type, and the luting agent. No statistical differences were recorded for sleeves not sandblasted, Nos. 1 and 2, regardless of the luting agent. The nonsandblasted No. 3 sleeve cemented with Panavia CRC had significantly greater retention than All-Bond CRC or ZOP. There were no statistical differences in retention of sandblasted sleeves for the No. 1 sleeve despite the type of luting agent. For sandblasted sleeves Nos. 2 and 3, ZOP and Panavia CRC recorded significantly greater retention than All-Bond CRC. However, there was no difference between sandblasting and not sandblasting for the No. 1 sleeve. Mean loads for Nos. 2 and 3 sleeves were substantially greater for sandblasted compared with attachments not sandblasted. (J PROSTHET DENT 1993;69:149-54.)
R
etention of an artificial crown to tooth structure or core material is critical for a successfulrestoration. A predictable, uncomplicated technique that provides retention of the crown to tooth structure will be welcomed.The Flexi-Cast crown/core system (Essential Dental Systems, S. Hackensack, N. J.) combinesa prefabricated post with a contiguous head and a precision attachment sleeve.The attachment sleeve is then incorporated in the finished artificial crown. The shaft portion of Flexi-Cast System is a prefabricated, highly retentive threaded split post, similar to the Flexi-Post dowel (Essential Dental Systems).1-5 The machined attachment sleevefor the Flexi-Cast system, constructed from stainlesssteel or titanium alloy, has circumferential groovesthat match circumferential grooves on the prefabricated post head. When the sleeve is cemented to the post head, the alignment of the sleeve grooves and the grooves in the post head results in outstanding retention of the sleeveto the post. The mean values reported for zinc oxyphosphate (ZOP) cementwithout sandblastingranged from a minimum of 125lb for the No. 1 size cast post to a maximum of 170.5lb for the No. 3 largest cast post.6 Malalignment of approximately 0.56
aVice-President of DentalResearch. bPrivatePractice,NewYork, NY; ClinicalInstructor, NewYork University Collegeof Dentistry. CCo-director of DentalResearch. CopyrightQ 1993by The Editorial Councilof THE JOURNAL OF PROSTHETIC DENTISTRY. 002%3913/93/$1.00 +.lO. FEBRUARY
1993
10/l/42662
Fig. 1. Vise grips of a universal testing machine for the sleevecemented with C & B Metabond CRC to the FlexiCast post head before testing.
mm, or 560 pm, for sleevescemented with ZOP cement without sandblastingto the correspondingcast post head did not causea lossof retention.7 Numerous commercial adhesive luting agents can be usedto cement metal to metal surfaces.Examples are C & B Metabond compositeresin cement (CRC) (Parke11Products, Inc., Farmingdale, N. Y.), All-Bond CRC (Bisco, Inc., Downers Grove, Ill.), and Panavia CRC (J. Morita, Tustin, Calif.). C & B Metabond CRC involves a I-MetalMMA-TBB 149
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OF PROSTHETIC
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DENTISTRY
ET AL
Fig.
2. Retentive failure for a Flexi-Cast sleeveand post head cemented (with C&B Metabond CRC, after testing.
Fig.
Table I. Retention of nonsandblastedand sandblasted sleevescemented with zinc oxyphosphate cement
Table III. Retention of nonsandblastedand sandblastedsleevescemented with All-Bond CRC
Sandblasted sleeves and Flexi-Cast post heads, group 4
Non-sandblasted sleeves6 Flexi-Cast sleeve No.
1 2 3
Mean
(lb)
125.8 137.1 170.5
SD 71.9 43.1 58.9
Mean
(lb)
109.7 247.0 260.6
Flexi-Cast sleeve No. 1 2 3
Mean 108.2 136.1 209.1
(lb)
1 SD
SD 34.9 99.0 130.0
1 2 3
37.7 37.0 73.5
Sandblasted sleeves and Flexi-Cast post heads, group 6 Mean 105.1 169.3 220.6
(lb)
SD 22.9 23.6 52.1
chemistry with the 4-Meta systemthat is purported to be hydrophilic and strong bonding for metal to metal surfaces or interfaces.8,g The All-Bond CRC system involves a primer A with NTG-GMA in acetoneand a primer B with BPMA in acetoneincluding an unfilled resin adhesivecontaining a hydrophilic monomer(HEMA).1°-12 Strong metal bondshave alsobeenreported for the All-Bond system.l’*l2 The Panavia CRC system incorporates a cumenehydroperoxide (CHP) initiation system,with monomerspolymerized without oxygen (anaerobic), resulting in strong bonding of metal to metal surfacesand interfaces.s This study determined the retentive values of Nos. 1
150
Non-sandblasted sleeves, group Flexi-Cast sleeve No.
Table II. Retention of nonsandblastedand sandblasted sleevescemented with C & B Metabond CRC Non-sandblasted sleeves, group
3. Enlargement of the cemented sleeve and post head after failure.
Mean
(lb)
157.7 180.4 157.6
2
Sandblasted sleeves and Flexi-Cast post heads, group 6
SD 58.9 39.3 31.8
Mean
(lb)
SD
114.5 128.9 159.6
27.7 37.3 45.5
through 3 stainless steel attachment sleeves that were sandblasted or not sandblastedand cemented with four luting agents.
MATERIAL
AND
METHODS
This experiment was divided in two parts, with seven groups. Part 1 included the retention of cementedattachment sleevesthat were not sandblastedand part 2 examined the retention of sandblastedattachment sleevesand cast post heads. In part 1 of the experiment, a total 90 (30 each for sizes No. 1,2, and 3) attachment sleeves(not sandblasted)were cemented to their corresponding post headswith C & B Metabond CRC (group l), All-Bond CRC (group 2), and Panavia CRC (group 3). All cementation procedures followed the manufacturer’s instructions. In part 2, a total of 120 (40 each for sizesNo. 1, 2, and 3) attachment sleevesand castpost headsweresandblasted and cementedto their correspondingpost headswith zinc oxyphosphate cement (ZOP) (Flecks zinc cement, Mizzy Inc., Cherry Hill, N. J.) (group 4), C & B Metabond CRC (group 5), All-Bond CRC (group 6), and Panavia CRC (group 7). All luting agentsand correspondingcementation proceduresfollowed the manufacturers’ instructions.
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RETENTIVE
PROPERTIES
WITH
VARIOUS
BONDING
THE
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DENTISTRY
Pounds 300
250
No. 1
No. 2
No.3
S, No. 1
S, No.2
S, No.3
S = Sandblasted Fig.
4. Retention of Flexi-Cast sleevescemented with ZOP.
Sandblasting for the attachment sleeve and cast post heads was performed with a sandblasting box (Handler Mfg. Co., Inc., Westfield, N. J.) connected to a 1 hp compressor (Speedaire, Dayton, Chicago, Ill.). A 240 mesh aluminum oxide abrasive powder (Ney-Brasive, J. M. Ney Co., Bloomfield, Conn.) was selected and Flexi-Cast post heads and matching sleeves were sandblasted until a roughened surface was evident. Sandblasting was performed for an averageof 2 to 3 minutesto create the desired surface. All cemented attachment sleeves(parts 1 and 2) set for at least 1 hour, and the specimenswere then immersedin 100% humidity for 1 week before tensile testing. Sleeves were subjected to a tensile force (Figs. 1 through 3) on a universal testina machine (Comten Industries, St. Petersburg, Fla.) until failure with a crossheadspeed of 0.25 inches per minute (0.635 cm/minute). This resulted in retentive failure for each attachment sleeve, measured in pounds, and failure was confirmed when the cemented sleevewas removed from the Flexi-Cast post head.
FEBRUARY
1999
Table IV. Retention of nonsandblastedand sandblasted sleevescemented with Panavia CRC Non-aaadblasted sleavaa, Group Flexi-Ca8t sleeve No. 1 2 3
STATISTICAL
Mean 136.0 163.2 261.9
(lb)
3 SD 27.0 29.6 64.2
Sandbhsted &eves and Flexl-Cast post Beads, group 7 lean 141.1 195.2 270.0 ----
(lb)
SD
-
24.5 48.4 63.0
METHODS
A 2 X 3 x 4 factorial three-way analysis of variance (ANOVA) was selected to compute the effects of sandblasting, sleeve and post type, and luting agent.13The result was considered statistically significant if p < 0.05.
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Pounds
250
T
200
150
100
50
-I
0 No.1
No.2
No.3
S = Sandblasted Fig.
5. Retention
of Flexi-Cast
I
-t
S, No.1
sleeves cemented
S,No.2
with
S, No.3
C & B Metabond
CRC.
Pounds
No. 1
No.2
No.3
S, No. 1
S,No.2
S, No.3
S = Sandblasted
Fig.
152
6. Retention
of Flexi-Cast
sleeves cemented
with All-Bond
CRC.
VOLUME
69
NUMBER
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RETENTIVE
PROPERTIES
WITH
VARIOUS
BONDING
THE
JOURNAL
OF PROS-I‘AFTIC‘
DENTISTRI
Pounds
250
200
150
100
50
0 No.
1
No. 2
No. 3
S, No.1
S, No.2
S, No.3
S = Sandblasted Fig.
7. Retention
of Flexi-Cast
RESULTS Retentive failure was recorded when the cemented sleeve was separated from the cast post head. Tables I-IV summarize sleeves not-sandblasted compared with sandblasted sleeves. Retention improved as the sleeve and the cast post head increased in sizes from No. 1 to No. 3 for all groups. ANOVA revealed that all two-way interactions were significant: (1) interaction of sandblast and sleeve and post number (p < 0.0126); (2) interaction of sandblast and cement (p < 0.0002); and (3) interaction of sleeve and post number and cement (p < 0.0014). There were no statistical differences in retention of sleeves not sandblasted for the Nos. 1 and 2 sleeves despite the type of cement. For the No. 3 nonsandblasted sleeve, Panavia CRC bonding was significantly greater than for All-Bond CRC and ZOP. The data suggested that C & B Metabond CRC retention was greater than that of AllBond CRC, whereas Panavia CRC retention was greater than that of Metabond CRC, but these results were barely statistically significant. For the cements All-Bond CRC and ZOP, there was no difference between the sleeves not sandblasted. For both C
FEBRUARY
1993
sleeves cemented
with Panavia
CRC.
& B Metabond CRC and Panavia CRC, No. 1 and No. 2 sleeves not sandblasted were similar, but each recorded significantly lower mean loads than the No. 3 nonsandblasted sleeve. For the sandblasted sleeve, no statistical difference in retention was observed for No. 1 sleeve despite the luting agent. For sleeve No. 2, ZOP and Panavia CRC had significantly greater retention than All-Bond CRC, with ZOP’s greater than that of C & B Metabond CRC. The data suggested that Panavia CRC retention was greater than that of C & B Metabond CRC, but the result was not statistically significant. The mean loads for ZOP and Panavia CRC for the No. 3 sleeve were significantly greater than for AllBond CRC, with ZOP superior to C (YEB Metabond CRC. The data implied that C & B Metabond CRC retention was greater than that of All-Bond CRC, but this result was also not statistically significant. Within cement groups, no difference was apparent for Nos. 1, 2, and 3 sandblasted sleeves using All-Bond CRC. For C & B Metabond CRC, the No. 3 sandblasted sleeve recorded greater retention than the No. I sandblasted sleeve. The data suggested that the No 2 sandblasted sleeve also had greater retention than that of the No. 1
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sandblasted sleeve, but this result was not statistically significant. For Panavia CRC, Nos. 2 and 3 sandblasted sleeves exhibited greater mean loads than the No. 1 sandblasted sleeves. For ZOP, Nos. 2 and 3 sandblasted sleeves had greater mean loads than the No. 1 sandblasted sleeves. There was no difference recorded for the No. 1 sleeve, sandblasted or not sandblasted. The mean load for Nos. 2 and 3 sleeves was statistically greater for sandblasting, but the significance was borderline. Only ZOP had mean loads for the sandblasted sleeves that were significantly greater than for the attachments not sandblasted. For the three remaining cements of All-Bond CRC, C & B Metabond CRC, and Panavia CRC, there were no significant differences between sandblasting and the type of cement.
DISCUSSION Retentive failure was recorded when the cemented sleeve was dislodged from its corresponding post head. The retention was more than 100 lb in this study regardless of the cement and the sandblasting of the attachments (Figs. 4 through 7). There was no statistical difference between samples without sandblasting despite cements used with the smaller sizes, Nos. 1 and 2, Flexi-Cast post and sleeves. However, when the No. 3 sleeve was tested, Panavia CRC had substantially more retention than All-Bond CRC and ZOP. The elevated retention reported for Panavia CRC was probably because of the greater cohesive strength for the cement compared with All-Bond CRC. All-Bond CRC consistently recorded the lowest values and there was no difference in retention with All-Bond CRC for the Nos. 1, 2, and 3 sleeves. This indicated that the cohesive strength for All-Bond CRC was low between metal interfaces. Sandblasted No. 1 sleeves did not result in a statistical difference with different luting agents. However, when Nos. 2 and 3 sleeves were tested, Panavia CRC and ZOP both had statistically more retention than All-Bond CRC. The greater retention observed for Panavia CRC and ZOP can be attributed to the superior cohesive strength for these cements compared with All-Bond CRC. All-Bond CRC and C & B Metabond CRC consistently recorded the least retention and Panavia CRC and ZOP the greatest. There was no difference in retention for Nos. 1, 2, and 3 sandblasted sleeves with All-Bond CRC. Differences between sandblasting and not sandblasting were recorded only for Nos. 2 and 3 Flexi-Cast sleeves and post head combinations. These two sizes benefited by the sandblasting.
154
COHEN
DENTISTRY
ET AL
CONCLUSIONS Two hundred forty Flexi-Cast post heads with their corresponding Flexi-Cast sleeves were cemented with four different luting agents: ZOP, Panavia CRC, All-Bond CRC and C & B Metabond CRC. Half of the samples were also sandblasted. 1. Panavia CRC and ZOP recorded the greatest retention and All-Bond CRC and C & B Metabond CRC exhibited the least. 2. Sandblasting significantly improved the retention for Flexi-Cast sleeves Nos. 2 and 3, compared with sleeve No. 1.
3. The retention for all sizes of Flexi-Cast sleeves and cements exceeded 100 lb for all groups in this study.
Contributing
author
Kongren Jiang, MS, Essential Dental Laboratories Research Engineer and Chemist. REFERENCES
5. 6. I. 8. 9.
10.
11.
12. 13.
Deutech AS, Musikant BL, CavaIlari J, Bemardi S. Retentive properties of a new post and core system. J PROSTHET DENT 1985,53:12-4. Millstein PL, Yu H, Hsu CS, Nathanson D: Effects of cementing on retention of a prefabricated screw post. J PROSTHET DENT 1987;67:171-4. Brown JD, Mitchem JC. Retentive properties of dowel post systems. Oper Dent 1987;12:15-9. Saunders RD, Lorey RE, Powers JM, Sloan KM. Comparison of five post-cement systems for tensile retentive capacity [Abstract]. J Dent Res 1988;67:304. Cohen BI, Mu&ant BL, Deutsch AS. Comparisonof the retentive properties of four post systems. J PROSTHET DENT 1992;68:264-8. Deutsch AS, Cohen BI, Musikant BL. Retentive properties of attachment sleeves for a new cast-post system. J PROSTHET DENT 1992;67:34-6. Cohen BI, Deutsch AS, Musikant BL. Retentive properties of misaligned post attachment sleeves. J PROSTHET DENT 1992;67:191-3. Barzilay I, Vassilas A. Panvia and 4-Meta bond to amalagam and NiCr alloy [Abstract]. J Dent Res 1996;69:363. Imbery TA, Burgess JO, Naylor WP. Tensile strength of resin cements with various alloy surface treatments [Abstracts]. J Dent Res 1991;70:390. DeSchepper EJ, Cailleteau JG, Roeder L, Powers JM. In vitro tensile bond strengths of amalgam to treated dentin. J Esthet Dent 1991;3:11720. Roeder LB, DeSchepper EJ, Powers JM. In vitro bond strength of repaired amalgam with adhesive bonding systems. J Esthet Dent 1991$126-S. Suh BI. All-bond fourth generation dentin bonding system. J Esthet Dent 1991;3:139-47. Zar JH. Biostatisticai analysis. Englewood CIiis, NJ: Prentice-Hall, 1974;151-4.
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