An evaluation
of polishing
James W. Stoddard,
agents for composite
D.D.S.,* and Glen H. Johnson,
resins
D.D.S., M.S.**
University of Washington, School of Dentistry, Seattle, Wash. After the gross reduction and fine finishing of a composite resin restoration, selecting a system to create the smoothest polish is dilllcult because high magnification is necessary to compare the surface roughness. The surfaces of four anterior and posterior composite resins were compared using a Mylar strip, an unfilled resin as a glaze, polishing with three rubber polishers, and three different manufacturers’ series of disks. This study suggested that pairing a specific composite resin with a matching polishing system produced the smoothest surface. Because of the differences in the size, shape, number of filler particles, and the type of resin, one system was incapable of creating the smoothest surface for all composite resins. (J PROSTHET DENT 1991;65:491-5.)
Since the introduction
MATERIAL
of composite resins, numerhave been initiated to develop a finishing
ous studies’-l7
AND METHODS
An anterior and a posterior composite resin from four manufacturers were selected so that differences in base resin and type and size of filler particle were represented (Table I). The anterior and posterior pairs of composite resins evaluated were Bis-Fil M and Bis-Fil I (BISCO, Inc., Lombard, Ill.), Prisma-Fil and Ful-Fil (L. D. Caulk Division, Dentsply International, Inc., Milford, Del.), Silux and P-30 (3M Co., St. Paul, Minn.), and Heliosit and Heliomolar (Vivadent [U.S.A.] Inc., Buffalo, N.Y.). Polishing instruments were chosen from two groups: abrasive disks or mounted abrasive points. A surface treated with a Mylar strip was used as a control, but one series was coated with an enamel bonding agent after polishing. The instruments evaluated were: the Mylar control, CompoSite (Shofu Dental Corp., Menlo Park, Calif.), Quasite (Shofu Dental Corp.), and Vivadent points (Vivadent
and polishing procedure that would produce a smoothsurfaced restoration. Frequently, by the time a study was completed, the resin and/or the polishers had been replaced by newer, different materials. These events identified a need for continuous research. This study evaluated the effectiveness of various polishing instruments on eight different composite resins.
Presented at the International Association for Dental Research meeting, Montreal, Quebec, Canada. Supported by National Institutes of Health grant No. RR-05346 and by BISCO, Inc. *Assistant Professor, Department of Restorative Dentistry. **Associate Professor, Department of Restorative Dentistry. 10/l/26877
Table I. Composite classification Composite
Manufacturer
Particle
BiSCO, Inc. Lombard, Ill. L.D. Caulk Milford, Del. 3M Co. St. Paul, Minn. Vivadent (USA) Inc. Buffalo, N.Y.
Microfill
Bis-Fil I
size
Filler
type
Resin
Anterior
Bis-Fil M
Fine particle
Strontium glass Colloidal silica Barium glass
Urethane-modified Bis-GMA
Microfill
Zinc glass
Bis-GMA
Microfill
Colloidal silica
Urethane-dimethacrylate
BISCO, Inc.
Hybrid
Bis-GMA
Ful-Fil
L.D. Caulk
Fine particle
P-30 Heliomolar
3M Co. Vivadent (U.S.A.) Inc.
Fine particle Microfill
Strontium glass Colloidal silica Barium glass Colloidal silica Zinc glass Colloidal silica
Prisma-Fil Silux Heliosit
Bis-GMA
Posterior
THE JOURNAL
OF PROSTHETIC
DENTISTRY
Urethane-modified Bis-GMA Bis-GMA Urethane Bis-GMA mixture
491
STODDARD
RaW-0 Instrument
,O
0.25
0.50
Instrument
1.00
Prisma Bond Mylar
Prisma Bond Super Snap disks
Moore’s disks SofLex disks
Vivadent Polishers
Super Sanp disks
SofLex disks
Vivadent Polishers
ranked by roughness produced on anterior composite resins. Fig.
1. Instruments
0
0.25
0.50
0.75
CompoSiie
1
Composite
JOHNSON
Ra(w) 0.75
Mylar Moore’s disks
Quasite
AND
1.oo
1
Quasite
Fig. 2. Instruments ranked by roughness produced on posterior composite resins.
Table II. Polishing instruments Product
Abrasive
CornpoSit points Quasite points Vivadent polishers
Aluminum oxide Aluminum oxide Silicon carbide Silicon carbide Aluminum oxide Aluminum oxide Aluminum oxide Silicium dioxide
DW DV Dry Wet DV Wet Wet Wet
PrismaBond
N/A
N/A
SofLex disks SuperSnapdisks Moore’s microfill compositepolishing kit
[U.S.A.] Inc.); SofLex (3M Co.), Moore (EC. Moore Co., Dearborn, Mich.), and SuperSnap (Shofu Dental Corp.) disks; and PrismaBond (L. D. Caulk Division, Dentsply International, Inc.) as a glaze after polishing (Table II). The specimens were prepared by placing the composite resin over retentive holes drilled in acrylic resin blocks (Plexiglass MC, Rohm and Haaa, Philadelphia, Pa.) covered with Mylar, and then compressed with another acrylic resin block using hand pressure. The block was then removed and each composite resin disk was light-cured for 40 seconds with an ESPE Elipar light (ESPE/Premier, Norristown, Pa.). This procedure produced five composite resin disks per block approximately 1.5 to 2 mm thick and 10 mm in diameter. Sixty-four blocks were prepared, resulting in a total of 320 specimens. The Mylar strips were removed and polishing was accomplished with the instruments in a hand-held Star Titan low-speed handpiece (Star Dental, Valley Forge, Pa.). Polishing instruments were applied for 30 seconds following the manufacturers’ instructions (Table II). Mylar strips and the polishing disks were used once and were then discarded, but the rubber points were reused ran492
Usage
Manufacturer
3M Co., St. Paul, Minn. Shofu Dental Corp. Menlo Park, Calif. E.C. Moore Co. Dearborn, Mich. Shofu Dental Corp. Shofu Dental Corp. Vivadent (USA) Inc. Buffalo, N.Y. L.D. Caulk Milford, Del.
domly. The sequence of the instruments followed manufacturers’ recommendations (Table III). After all specimens were polished, they were thoroughly rinsed with water and allowed to dry for 24 hours before measurement of the average surface roughness (Ra). Testing for each combination of composite resin and polishing instrument was accomplished with a Surfanalyzer 4000 instrument (Federal Products, Providence, R.I.). Three measurements were recorded for the five specimens on a block, the mean Ra was determined for each specimen, and an overall Ra was determined for the total sample. Data were analyzed using one- and two-factor analysis of variance. If differences were significant, the Student-Neuman-Kuels program for pair-wise comparison of means was computed using a 95% level of confidence. Scanning electron micrographs (SEMs) were made of selected specimens for detailed examination of surface topography. RESULTS The average Ra measurements for combinations of composite resins and polishing instruments are presented in Table IV. APRIL
lSB1
VOLUME
66
NUMBER
4
COMPOSITE
RESIN
POLISHING
AGENTS
Table
Ra (crm) Composite 0
0.2
0.4
0.6
0.6
III.
Polishing sequence
Instrument
Sequence
Mylar CompoSite Quasite SofLex SuperSnap Moore’s
None None CompoSite Medium-fine-superfine Coarse-medium-fine Adalox medium Waterproof fine-xx fine-microfine Finisher-polisher SofLex medium-fine-superfine
Vivadent PrismaBond
Fig. 3. Composite resins ranked by roughness for all finishing instruments.
Table
IV.
Average surface roughness (Ra) in microns
Composite
Bis-Fil M Prisma-Fil Silux HeIiosit Bis-Fil I Ful-Fil P-30 Heliomolar
Mylar
0.2 0.2 0.2 0.2 0.3 0.3 0.1 0.2
Composite
1.0 1.0 1.0 1.1 0.9 0.9 1.2 0.8
Quasite
SofLex
1.0 0.8 0.9 1.0 0.9 0.9 1.3 0.7
Instruments were ranked by roughness on anterior composite resins by means of a bar graph (Fig. 1). The results revealed three distinct groupings of roughness without overlapping. Mylar, PrismaBond, Moore disks, and SuperSnap disks make up the first group, while the second group consisted of Vivadent Polishers and SofLex disks. The final group contained Composite and Quasite rubber points. The results for the posterior composite resins (Fig. 2) were not distinct, with only two separate groups. The Composite and Quasite points formed one group, while the remaining five instruments were distributed into overlapping groups. The composite resins were ranked by average roughness (Ra) for all polishing instruments except PrismaBond, which was considered a post-polish treatment and not a polishing instrument. Analysis revealed only two groupings, with P-30 resin in one and the remaining seven composite resins in the other (Fig. 3). The Ra for the anterior composite resins was 0.5 km and for the posterior composite resins it was 0.6 pm 0, = 0.045). Figs. 4 through 7 are selected SEM photographs of one manufacturer’s composite resin. A Mylar-produced surface and a surface resulting from application of PrismaBond material are also exhibited. THE
JOURNAL
OF PROSTHETIC
DENTISTRY
0.4 0.4 0.3 0.8 0.4 0.6 0.8 0.2
SuperSnap
0.2 0.4 0.2 0.4 0.2 1.0 0.7 0.1
Moore
0.3 0.2 0.2 0.2 0.2 0.3 0.5 0.4
Vivadent
0.5 0.4 0.6 0.2 0.7 0.5 1.2 0.3
PrismaBond
0.2 0.3 0.3 0.2 0.1 0.1 0.2 0.2
DISCUSSION The surface roughness created by the rubber points was expected to be greater than that created by the other polishing instruments,17 but this was only evident for the CompoSite and Quasite points. They recorded near identical values and a roughness that was approximately double for the disks. However, the Vivadent rubber points were grouped with the disks, and for specific composite resins, created a smoother surface than certain types of disks. Because the specimens polished with Composite points were similar in roughness to the Composite-Quasite sequence with a difference no greater than 0.1 Km, it is suggested that either point is indicated, rather than a sequence. Also, both points created nearly identical roughness on seven of the eight composite resins, but this differed slightly from the results of a previous investigation.13 The roughness for the three types of disks was comparable, and the Moore disks created a surface similar to that of a Mylar or PrismaBond application. For the anterior composite resins, the SuperSnap and Moore disks created a smoother surface than the SofLex, while the mean roughness for the posteriors was almost the same. These. results differed only slightly from those of an earlier investigation by Hassan et al. l6 Although the roughness for the three types of disks exhibited no substantial differences, 493
STODDARD
Fig. 4. SEM photograph of Bis-Fil I composite resin and a Mylar-produced surface. (Original magnification x200.)
AND
JOHNSON
Fig. 6. SEM photograph of Bis-Fil I composite resin and a PrismaBond-produced surface. (Original magnification X500.)
Fig. 5. SEM photograph of Bis-Fil I composite resin and a Mylar-produced surface. (Original magnification x500.)
there were other considerations in selecting a disk for polishing. There are problems with creating discoloration on the surface of the composite resin from contact with the head of the mandrel using SofLex and Moore disks.lp l7 There is also limited standardization among disks concerning designations such as coarse, medium, fine, etc. Pratten and Johnson17 demonstrated that the SofLex coarse disk created a surface roughness twice that of the SuperSnap coarse disk on the same composite resin. However, the Ra for the SofLex medium disk was nearly equal to that of the SuperSnap coarse disk.
494
Fig. 7. SEM photograph of Bis-Fil M composite resin and a PrismaBond-produced surface. (Original magnification X500.)
One unexpected result related to the surface roughness concerned the use of a Mylar strip, because it has been accepted that Mylar strips created the smoothest surface and polishing should be directed toward mimicking that standard.5t l5 Nevertheless, PrismaBond material applied over the polished surface of posterior composite resin resulted in a surface equal to that of a Mylar strip. For the anterior composite resins, the roughnesses created by My-
APRIL
1991
VOLUME
65
NUMBER
4
COMPOSITE
RESIN POLISHING
AGENTS
lar, Moore disks, PrismaBond, and SuperSnap disks were placed in the same group. The SEM photos (Figs. 4 through 6) revealed that large voids were created under the Mylar on the posterior composite resin surface that could he corrected by the application of the PrismBond material. Fig. 7 illustrates an anterior composite resin with the uneven layer of PrismaBond material that was common to all the anteriors. Uneven adherence of a glaze coat over highly polished composite resin surfaces was previously reported by Calatrava et a1.3 Although slight differences were discovered between certain pairs of anterior and posterior composite resins, only P-30 exhibited a statistically significant difference (Fig. 3). Bis-Fil M and Bis-Fil I, and Prisma-Fil and Ful-Fil resins recorded minimal differences in roughness. Silux and P-30 resins displayed the greatest variance within the pairs, but Heliosit and Heliomolar resins revealed the most interesting variation in roughness, because four instruments produced the smoothest surface on the posterior resin.
SUMMARY This study suggested that surface roughness can be determined by both the characteristics of the polishing instrument and by the properties of the composite resinnamely, filler type, par&al size, amount of filler, and type of resin. The results verified that different surface roughnesses can be created using identical instruments on different composite resins. The Vivadent polisher produced the smoothest surface of the rubber points, while Moore’s disks created a surface similar to that of both Mylar and a resin glaze of PrismaBond material.
REFERENCES
2. Batter JG, Caputo AA. The surface of composite resin finished with instruments and matrixes. J PR~SI-HET DENT 1983;50:351-7. 3. Calatrava L, Dennison J, Charbeneau G. Clinical evaluation of two
glazing agents for composite resin: a preliminary report. J Oper Dent 1976;1:82-90. 4. Christensen RP, Christensen GJ. Comparison of instruments and commercial pastes used for finishing and polishing composite resin. Gen Dent 1981;29:40-5. 5. Dennison JB, Fan PL, Powers JM. Surface roughness of microfilled composites. J Am Dent Assoc 1981;102:859-62. 6. Ferreira MR, and De Wet FA. Effect of finishing agents on new restorative resins: a SEM study [Abstract]. J Dent Res 1982;61:605. I. Louka AN, Stillwater JC. Effectiveness of different finishing systems on composite resin surfaces [Abstract]. J Dent Res 1982;61:302. 8. Lambrechts P, Vanherle G. Observation and comparison of polished composite surface with the aid of SEM and profilometer. Part 1. J Oral Rehabil 1982;9:169-82. 9. Lambrechts P, Vanherle G. Observation and comparison of polished composite surface with the aid of SEM and profilometer. Part II. J Oral Rehabil 1982;9:203-16. 10. Kanter J, Koski RE. An evaluation of new methods for polishing composite restorative resins. Quintessence Int 1980;8:91-5. 11. Kanter J, Koski RE, Bogdan MS. How to achieve the best surface polish on composite resins. Can Dent Assoc J 1983;5:40-5. 12. Pearson GJ, Messing JJ. The abrasivity of finishing agents used on composite filling material. J Dent 1979;7:105-10. 13. Quiroz L, Lents DL. The effect of polishing procedures on light-cured composite restorations. Compend Cont Educ Dent 1985;6:437-42. 14. Reinhardt JW, et al. Determining smoothness of polished microfilled composite resins. J PROSTHET DENT 1983;49:485-90. 15. Lutz F, Setco J, Phillips R. New finishing instruments for composite resins. J Am Dent Assoc 1983;107:575-80. 16. Hassan K, Dhuru V, Brantley W. Comparison of the efficiency of two composite finishing systems-a laboratory study [Abstract]. J Dent Res 1987;66:211. 17. Pratten D, Johnson G. An evaluation of finishing instruments for an anterior and a posterior composite resin. J PROSTHET DENT 1988;60: 154-8.
Reprintrequeststot DR. JAMB W. STODDARD SCHOOL OF DENTISTRY, SM-56 UNIVERSITY OF WASHINGTON SEATTLE, WA 98195
1. St&y C, Kopel H. Smoothness of composite restorations polished by various abrasives: a comparison by scanning electron microscopy. J Oper Dent 1979;4:140-8.
Availability
of JOURNALback issues, 1986-1989
Back issuesof THEJOURNAL OFPROSTHETIC DENTISTRYare available for purchase from the publisher, Mosby-Year Book, Inc., at a cost of $6.50 per issue. (Foreign postage is not included.) The following quantity discounts are available: 25% off on quantities of 12 to 23, and one third off on quantities of 24 or more. Please write to Mosby-Year Book, Inc., Subscription Services, 11830 Westline Industrial Drive, St. Louis, MO 63146-3318, or call (314)453-4351 for information on availability of particular issues for that period from 1978 to 1989. If unavailable from the publisher, photocopies of complete issues are available from University Microforms International, 300 N. Zeeb Rd., Ann Arbor, MI 48106, (313)761-4700.
THE JOURNAL
OF PROSTHETIC
DENTISTRY
495
of polishing
James W. Stoddard,
agents for composite
D.D.S.,* and Glen H. Johnson,
resins
D.D.S., M.S.**
University of Washington, School of Dentistry, Seattle, Wash. After the gross reduction and fine finishing of a composite resin restoration, selecting a system to create the smoothest polish is dilllcult because high magnification is necessary to compare the surface roughness. The surfaces of four anterior and posterior composite resins were compared using a Mylar strip, an unfilled resin as a glaze, polishing with three rubber polishers, and three different manufacturers’ series of disks. This study suggested that pairing a specific composite resin with a matching polishing system produced the smoothest surface. Because of the differences in the size, shape, number of filler particles, and the type of resin, one system was incapable of creating the smoothest surface for all composite resins. (J PROSTHET DENT 1991;65:491-5.)
Since the introduction
MATERIAL
of composite resins, numerhave been initiated to develop a finishing
ous studies’-l7
AND METHODS
An anterior and a posterior composite resin from four manufacturers were selected so that differences in base resin and type and size of filler particle were represented (Table I). The anterior and posterior pairs of composite resins evaluated were Bis-Fil M and Bis-Fil I (BISCO, Inc., Lombard, Ill.), Prisma-Fil and Ful-Fil (L. D. Caulk Division, Dentsply International, Inc., Milford, Del.), Silux and P-30 (3M Co., St. Paul, Minn.), and Heliosit and Heliomolar (Vivadent [U.S.A.] Inc., Buffalo, N.Y.). Polishing instruments were chosen from two groups: abrasive disks or mounted abrasive points. A surface treated with a Mylar strip was used as a control, but one series was coated with an enamel bonding agent after polishing. The instruments evaluated were: the Mylar control, CompoSite (Shofu Dental Corp., Menlo Park, Calif.), Quasite (Shofu Dental Corp.), and Vivadent points (Vivadent
and polishing procedure that would produce a smoothsurfaced restoration. Frequently, by the time a study was completed, the resin and/or the polishers had been replaced by newer, different materials. These events identified a need for continuous research. This study evaluated the effectiveness of various polishing instruments on eight different composite resins.
Presented at the International Association for Dental Research meeting, Montreal, Quebec, Canada. Supported by National Institutes of Health grant No. RR-05346 and by BISCO, Inc. *Assistant Professor, Department of Restorative Dentistry. **Associate Professor, Department of Restorative Dentistry. 10/l/26877
Table I. Composite classification Composite
Manufacturer
Particle
BiSCO, Inc. Lombard, Ill. L.D. Caulk Milford, Del. 3M Co. St. Paul, Minn. Vivadent (USA) Inc. Buffalo, N.Y.
Microfill
Bis-Fil I
size
Filler
type
Resin
Anterior
Bis-Fil M
Fine particle
Strontium glass Colloidal silica Barium glass
Urethane-modified Bis-GMA
Microfill
Zinc glass
Bis-GMA
Microfill
Colloidal silica
Urethane-dimethacrylate
BISCO, Inc.
Hybrid
Bis-GMA
Ful-Fil
L.D. Caulk
Fine particle
P-30 Heliomolar
3M Co. Vivadent (U.S.A.) Inc.
Fine particle Microfill
Strontium glass Colloidal silica Barium glass Colloidal silica Zinc glass Colloidal silica
Prisma-Fil Silux Heliosit
Bis-GMA
Posterior
THE JOURNAL
OF PROSTHETIC
DENTISTRY
Urethane-modified Bis-GMA Bis-GMA Urethane Bis-GMA mixture
491
STODDARD
RaW-0 Instrument
,O
0.25
0.50
Instrument
1.00
Prisma Bond Mylar
Prisma Bond Super Snap disks
Moore’s disks SofLex disks
Vivadent Polishers
Super Sanp disks
SofLex disks
Vivadent Polishers
ranked by roughness produced on anterior composite resins. Fig.
1. Instruments
0
0.25
0.50
0.75
CompoSiie
1
Composite
JOHNSON
Ra(w) 0.75
Mylar Moore’s disks
Quasite
AND
1.oo
1
Quasite
Fig. 2. Instruments ranked by roughness produced on posterior composite resins.
Table II. Polishing instruments Product
Abrasive
CornpoSit points Quasite points Vivadent polishers
Aluminum oxide Aluminum oxide Silicon carbide Silicon carbide Aluminum oxide Aluminum oxide Aluminum oxide Silicium dioxide
DW DV Dry Wet DV Wet Wet Wet
PrismaBond
N/A
N/A
SofLex disks SuperSnapdisks Moore’s microfill compositepolishing kit
[U.S.A.] Inc.); SofLex (3M Co.), Moore (EC. Moore Co., Dearborn, Mich.), and SuperSnap (Shofu Dental Corp.) disks; and PrismaBond (L. D. Caulk Division, Dentsply International, Inc.) as a glaze after polishing (Table II). The specimens were prepared by placing the composite resin over retentive holes drilled in acrylic resin blocks (Plexiglass MC, Rohm and Haaa, Philadelphia, Pa.) covered with Mylar, and then compressed with another acrylic resin block using hand pressure. The block was then removed and each composite resin disk was light-cured for 40 seconds with an ESPE Elipar light (ESPE/Premier, Norristown, Pa.). This procedure produced five composite resin disks per block approximately 1.5 to 2 mm thick and 10 mm in diameter. Sixty-four blocks were prepared, resulting in a total of 320 specimens. The Mylar strips were removed and polishing was accomplished with the instruments in a hand-held Star Titan low-speed handpiece (Star Dental, Valley Forge, Pa.). Polishing instruments were applied for 30 seconds following the manufacturers’ instructions (Table II). Mylar strips and the polishing disks were used once and were then discarded, but the rubber points were reused ran492
Usage
Manufacturer
3M Co., St. Paul, Minn. Shofu Dental Corp. Menlo Park, Calif. E.C. Moore Co. Dearborn, Mich. Shofu Dental Corp. Shofu Dental Corp. Vivadent (USA) Inc. Buffalo, N.Y. L.D. Caulk Milford, Del.
domly. The sequence of the instruments followed manufacturers’ recommendations (Table III). After all specimens were polished, they were thoroughly rinsed with water and allowed to dry for 24 hours before measurement of the average surface roughness (Ra). Testing for each combination of composite resin and polishing instrument was accomplished with a Surfanalyzer 4000 instrument (Federal Products, Providence, R.I.). Three measurements were recorded for the five specimens on a block, the mean Ra was determined for each specimen, and an overall Ra was determined for the total sample. Data were analyzed using one- and two-factor analysis of variance. If differences were significant, the Student-Neuman-Kuels program for pair-wise comparison of means was computed using a 95% level of confidence. Scanning electron micrographs (SEMs) were made of selected specimens for detailed examination of surface topography. RESULTS The average Ra measurements for combinations of composite resins and polishing instruments are presented in Table IV. APRIL
lSB1
VOLUME
66
NUMBER
4
COMPOSITE
RESIN
POLISHING
AGENTS
Table
Ra (crm) Composite 0
0.2
0.4
0.6
0.6
III.
Polishing sequence
Instrument
Sequence
Mylar CompoSite Quasite SofLex SuperSnap Moore’s
None None CompoSite Medium-fine-superfine Coarse-medium-fine Adalox medium Waterproof fine-xx fine-microfine Finisher-polisher SofLex medium-fine-superfine
Vivadent PrismaBond
Fig. 3. Composite resins ranked by roughness for all finishing instruments.
Table
IV.
Average surface roughness (Ra) in microns
Composite
Bis-Fil M Prisma-Fil Silux HeIiosit Bis-Fil I Ful-Fil P-30 Heliomolar
Mylar
0.2 0.2 0.2 0.2 0.3 0.3 0.1 0.2
Composite
1.0 1.0 1.0 1.1 0.9 0.9 1.2 0.8
Quasite
SofLex
1.0 0.8 0.9 1.0 0.9 0.9 1.3 0.7
Instruments were ranked by roughness on anterior composite resins by means of a bar graph (Fig. 1). The results revealed three distinct groupings of roughness without overlapping. Mylar, PrismaBond, Moore disks, and SuperSnap disks make up the first group, while the second group consisted of Vivadent Polishers and SofLex disks. The final group contained Composite and Quasite rubber points. The results for the posterior composite resins (Fig. 2) were not distinct, with only two separate groups. The Composite and Quasite points formed one group, while the remaining five instruments were distributed into overlapping groups. The composite resins were ranked by average roughness (Ra) for all polishing instruments except PrismaBond, which was considered a post-polish treatment and not a polishing instrument. Analysis revealed only two groupings, with P-30 resin in one and the remaining seven composite resins in the other (Fig. 3). The Ra for the anterior composite resins was 0.5 km and for the posterior composite resins it was 0.6 pm 0, = 0.045). Figs. 4 through 7 are selected SEM photographs of one manufacturer’s composite resin. A Mylar-produced surface and a surface resulting from application of PrismaBond material are also exhibited. THE
JOURNAL
OF PROSTHETIC
DENTISTRY
0.4 0.4 0.3 0.8 0.4 0.6 0.8 0.2
SuperSnap
0.2 0.4 0.2 0.4 0.2 1.0 0.7 0.1
Moore
0.3 0.2 0.2 0.2 0.2 0.3 0.5 0.4
Vivadent
0.5 0.4 0.6 0.2 0.7 0.5 1.2 0.3
PrismaBond
0.2 0.3 0.3 0.2 0.1 0.1 0.2 0.2
DISCUSSION The surface roughness created by the rubber points was expected to be greater than that created by the other polishing instruments,17 but this was only evident for the CompoSite and Quasite points. They recorded near identical values and a roughness that was approximately double for the disks. However, the Vivadent rubber points were grouped with the disks, and for specific composite resins, created a smoother surface than certain types of disks. Because the specimens polished with Composite points were similar in roughness to the Composite-Quasite sequence with a difference no greater than 0.1 Km, it is suggested that either point is indicated, rather than a sequence. Also, both points created nearly identical roughness on seven of the eight composite resins, but this differed slightly from the results of a previous investigation.13 The roughness for the three types of disks was comparable, and the Moore disks created a surface similar to that of a Mylar or PrismaBond application. For the anterior composite resins, the SuperSnap and Moore disks created a smoother surface than the SofLex, while the mean roughness for the posteriors was almost the same. These. results differed only slightly from those of an earlier investigation by Hassan et al. l6 Although the roughness for the three types of disks exhibited no substantial differences, 493
STODDARD
Fig. 4. SEM photograph of Bis-Fil I composite resin and a Mylar-produced surface. (Original magnification x200.)
AND
JOHNSON
Fig. 6. SEM photograph of Bis-Fil I composite resin and a PrismaBond-produced surface. (Original magnification X500.)
Fig. 5. SEM photograph of Bis-Fil I composite resin and a Mylar-produced surface. (Original magnification x500.)
there were other considerations in selecting a disk for polishing. There are problems with creating discoloration on the surface of the composite resin from contact with the head of the mandrel using SofLex and Moore disks.lp l7 There is also limited standardization among disks concerning designations such as coarse, medium, fine, etc. Pratten and Johnson17 demonstrated that the SofLex coarse disk created a surface roughness twice that of the SuperSnap coarse disk on the same composite resin. However, the Ra for the SofLex medium disk was nearly equal to that of the SuperSnap coarse disk.
494
Fig. 7. SEM photograph of Bis-Fil M composite resin and a PrismaBond-produced surface. (Original magnification X500.)
One unexpected result related to the surface roughness concerned the use of a Mylar strip, because it has been accepted that Mylar strips created the smoothest surface and polishing should be directed toward mimicking that standard.5t l5 Nevertheless, PrismaBond material applied over the polished surface of posterior composite resin resulted in a surface equal to that of a Mylar strip. For the anterior composite resins, the roughnesses created by My-
APRIL
1991
VOLUME
65
NUMBER
4
COMPOSITE
RESIN POLISHING
AGENTS
lar, Moore disks, PrismaBond, and SuperSnap disks were placed in the same group. The SEM photos (Figs. 4 through 6) revealed that large voids were created under the Mylar on the posterior composite resin surface that could he corrected by the application of the PrismBond material. Fig. 7 illustrates an anterior composite resin with the uneven layer of PrismaBond material that was common to all the anteriors. Uneven adherence of a glaze coat over highly polished composite resin surfaces was previously reported by Calatrava et a1.3 Although slight differences were discovered between certain pairs of anterior and posterior composite resins, only P-30 exhibited a statistically significant difference (Fig. 3). Bis-Fil M and Bis-Fil I, and Prisma-Fil and Ful-Fil resins recorded minimal differences in roughness. Silux and P-30 resins displayed the greatest variance within the pairs, but Heliosit and Heliomolar resins revealed the most interesting variation in roughness, because four instruments produced the smoothest surface on the posterior resin.
SUMMARY This study suggested that surface roughness can be determined by both the characteristics of the polishing instrument and by the properties of the composite resinnamely, filler type, par&al size, amount of filler, and type of resin. The results verified that different surface roughnesses can be created using identical instruments on different composite resins. The Vivadent polisher produced the smoothest surface of the rubber points, while Moore’s disks created a surface similar to that of both Mylar and a resin glaze of PrismaBond material.
REFERENCES
2. Batter JG, Caputo AA. The surface of composite resin finished with instruments and matrixes. J PR~SI-HET DENT 1983;50:351-7. 3. Calatrava L, Dennison J, Charbeneau G. Clinical evaluation of two
glazing agents for composite resin: a preliminary report. J Oper Dent 1976;1:82-90. 4. Christensen RP, Christensen GJ. Comparison of instruments and commercial pastes used for finishing and polishing composite resin. Gen Dent 1981;29:40-5. 5. Dennison JB, Fan PL, Powers JM. Surface roughness of microfilled composites. J Am Dent Assoc 1981;102:859-62. 6. Ferreira MR, and De Wet FA. Effect of finishing agents on new restorative resins: a SEM study [Abstract]. J Dent Res 1982;61:605. I. Louka AN, Stillwater JC. Effectiveness of different finishing systems on composite resin surfaces [Abstract]. J Dent Res 1982;61:302. 8. Lambrechts P, Vanherle G. Observation and comparison of polished composite surface with the aid of SEM and profilometer. Part 1. J Oral Rehabil 1982;9:169-82. 9. Lambrechts P, Vanherle G. Observation and comparison of polished composite surface with the aid of SEM and profilometer. Part II. J Oral Rehabil 1982;9:203-16. 10. Kanter J, Koski RE. An evaluation of new methods for polishing composite restorative resins. Quintessence Int 1980;8:91-5. 11. Kanter J, Koski RE, Bogdan MS. How to achieve the best surface polish on composite resins. Can Dent Assoc J 1983;5:40-5. 12. Pearson GJ, Messing JJ. The abrasivity of finishing agents used on composite filling material. J Dent 1979;7:105-10. 13. Quiroz L, Lents DL. The effect of polishing procedures on light-cured composite restorations. Compend Cont Educ Dent 1985;6:437-42. 14. Reinhardt JW, et al. Determining smoothness of polished microfilled composite resins. J PROSTHET DENT 1983;49:485-90. 15. Lutz F, Setco J, Phillips R. New finishing instruments for composite resins. J Am Dent Assoc 1983;107:575-80. 16. Hassan K, Dhuru V, Brantley W. Comparison of the efficiency of two composite finishing systems-a laboratory study [Abstract]. J Dent Res 1987;66:211. 17. Pratten D, Johnson G. An evaluation of finishing instruments for an anterior and a posterior composite resin. J PROSTHET DENT 1988;60: 154-8.
Reprintrequeststot DR. JAMB W. STODDARD SCHOOL OF DENTISTRY, SM-56 UNIVERSITY OF WASHINGTON SEATTLE, WA 98195
1. St&y C, Kopel H. Smoothness of composite restorations polished by various abrasives: a comparison by scanning electron microscopy. J Oper Dent 1979;4:140-8.
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