Abrasion of Class 1 restorative resins KNUD DREYER J0RGENSEN, PREBEN H0RSTED, OLE JANUM,JESPER KROGH AND JYTTE SCHULTZ Department of Technology, Royal Dental College, Copenhagen, and Department of Operative Dentistry, Royal Dental College, Aarhus, Denmark
Jorgensen, K, D,, Horsted, P,, Janum, O,, Krogh, J, Sc Schultz, J,: Abrasion of Class I restorativeresins, Scand,J,Dent, Res, 1979:87: HO-145. Abstract - Studies have been made on the abrasion by food of difFerent restorative resins in standard Class 1 cavities in mandibular first molars of schoolchildren. The abrasion was recorded by measuring the increasing height of the exposed cavity walls. It was found that Sevriton Simplified* was abraded more than Adaptic*, that no difference in abrasion between Adaptic and Adaptic without filler could be demonstrated, and that Adaptic was abraded more than an experimental composite containing 30% by weight Aerosil®, an ultra-fine SiOj filler with a grain sixe of the order of 25-50 nm. The results are in accord with the findings in an initial study by one of the present authors, in which the fillings were placed in denture porcelain teeth. It is stressed that the conclusions of the present work are pertinent only to the type of abrasion studied, i,e. chewing of food without the possibility of direct contact between the fillings involved and the coiTesponding antagonists. Keywords: dental materials; dentistry, operative; resins, K, Dreyer Jorgensen, Department of Technology, Royal Dental College, 160 Jagtvej, DK-2100. Copenhagen 0 , Denmark.
Accepted for publication 4 November 1978,
The present investigation is a continuation of an earlier quantitative study (2) o n the ocdusal abrasion by food of restorative resins. In this earlier study the fillings , J , ,,, J were placed m maxillary denture r / porcelain premolars and molars. In the present work all fillings were made in mandibular permanent first natural molars; the aim of the work was to study 1 , , L r j r j , r r , tne abrasion by tood ot diiterent resins, ' ' composite and non-composite, under ordinary physiologic conditions,
Materials and methods The following resinous restorative materials "'^''^^ "^'^ Adaptid* (Johtison & Johnson, New Jersey, U,S,A,), 2) Adaptic without filler, . •' ' . . '^ ^ . ., i,e, a non-composite resm of a similar composition as the resin in the Adaptic composite; the material was furnished by Johnson & Johnson, 3) Sevriton Simplified* (De Trey ^^"0
80 120 AS-75/G2
Discussion
Fig. 4. Abrasion of Adaptic versus AS-75/G2. Each point in the diagram is representative of one pair of fillings of a given patient.
It appears that the development of the composite type of restorative resins was based in part on the philosophy that such resins would show more resistance to the abrasion by different factors in the oral cavity than similar non-composite restoratives. This philosophy has been supported by comprehensive studies (mainly unpublished) in several research laboratories. Since, however, laboratory studies on abrasion frequently are inconclusive for the practical use of the materials involved, the possibility exists thai the abrasion resistance philosophy of the conventional type of composite dental resins is incorrect. The authors of the present work were unable to demonstrate a difference in abrasion by chewing of food between one well-known brand of composite resin (Johnson 8c Johnson's Adaptic) and a similar resin without filler. This finding is
supported by an earlier study (2) in which the composite brand Compocap® made by Ivoclar and a similar resin without filler were used. It should be noted, however, that the rate of abrasion in the present study was higher than in the earlier study in which the fillings were placed in porcelain teeth of full maxillary dentures. Other conclusions of the present investigation that Adaptic with a high degree of probability is abraded less than Sevriton Simplified but more than the micro-Hl! experimental composite AS75/G2, are also supported by the previous study mentioned above. The fact that AS73/G2 was abraded significantly less than Adaptic is possibly explainable by the observation by J0RGENSEN (2} that a distance between neighbor filler particles not exceeding approximately 0,1 fim will
ABRASION OF RESTORATIVE RESIN
prevent food abrasion of the resin component of the composite material. Assuming a uniform distribution of the liiier particles, larger distances berween neighbor filler particles are not liable to occur in the experimental composite in which the diameter of the individual particles is of the order of 25—50 nm. Several other clinical reports are available on the abrasion of resinous restoratives in occlusal cavities (1, 3—S). The abrasion in most of these papers is given in qualitative or relative terms; a comparison with the findings in the present work is therefore hardly possible. Only in the paper by RovLEJet at. (8) and by MEIER SC LUTZ (4) was a quantitative
145
may result in a different classification of the various restorative resins.
References 1. EAMES. W. B., S T S A I N J . D., WEITMAN, R. T.
& WILLIAMS, A. K.: Clinical comparison of composite, amalgam, and silicate restorations./. Am. Dent. Assoc. 1974: 89: 1111-1117 2. J0RGENSE.M, K. D. & AsMtsssEN, E.: Occlusal abrasion of a composite restorative resin with ultra-fine filler - an initial study. Quintessence Int. 1978: 8, No. 6: 73-78 3. LEINFELDER, K. F., SLUDER, T. B., SOCKWELL, C. L., STRICKLA.ND, W . D . & WALL. J. T.:
Clinical evaluation of composite, resins as anterior and posterior restorative materials. J. Prosthet. Dent. 1975:33:407-416
method used which permitted a recording 4. MEIER, C, & LLTZ. F. : Verschleissmessungen ol the abrasion in micrometer per time in vivo an okklusalen Komposit- und Amalgamfulltmgen. Dtich. Zahnaerztl. Z. unit. Since, however, the method of 1978:33:617-622 recording the abrasion in the latter two papers deviates significantly firom that in 5. NucKLES, D. B. Sc FINGAR.W, W.: Six-month and one-year clinical evaluation of a the present work, a detailed statistical composite resin for Class II restorations. / . compariso.n of the results is hardly Am. Dent, .iisoc. 1975:91: 1017-1022 justified; the findings in the two papers, 6. OSBORNE, J. W,, GALE, E. N . SC FERGUSON, G. W.: One-year and two-year clinical on the other hand, do not suggest a disevaluation of a composite resin vs. amalgam. agreement with those reported above. J. Proithet. Dent. 1973:30: 795-800 It should be stressed that the results of 7. PHILLIPS. R. W., AVERY, D . R., MEHRA, R., SWARTZ, M. L, SCMCCU.ME.R.,].: Observations the present work are pertinent only to the on a composite resin for Class 11 restorations: type of abrasion studied, namely chewing Three-year report./, Prosthet. Dent. 1973: 30: ol food without the possibility of direct 891-897 contact between the fillings involved and 8. RouLET, J. F,, METTLER. P. & FRIEDRICH. U, : the corresponding antagonists. Studies on Die Abrasion von Amalgam und Komposits the effect of other oral abrasion factors im Seitenzahnbereich. Dtsch. Zahnaerztl. Z. 1978:33:206-209
Jorgensen, K, D,, Horsted, P,, Janum, O,, Krogh, J, Sc Schultz, J,: Abrasion of Class I restorativeresins, Scand,J,Dent, Res, 1979:87: HO-145. Abstract - Studies have been made on the abrasion by food of difFerent restorative resins in standard Class 1 cavities in mandibular first molars of schoolchildren. The abrasion was recorded by measuring the increasing height of the exposed cavity walls. It was found that Sevriton Simplified* was abraded more than Adaptic*, that no difference in abrasion between Adaptic and Adaptic without filler could be demonstrated, and that Adaptic was abraded more than an experimental composite containing 30% by weight Aerosil®, an ultra-fine SiOj filler with a grain sixe of the order of 25-50 nm. The results are in accord with the findings in an initial study by one of the present authors, in which the fillings were placed in denture porcelain teeth. It is stressed that the conclusions of the present work are pertinent only to the type of abrasion studied, i,e. chewing of food without the possibility of direct contact between the fillings involved and the coiTesponding antagonists. Keywords: dental materials; dentistry, operative; resins, K, Dreyer Jorgensen, Department of Technology, Royal Dental College, 160 Jagtvej, DK-2100. Copenhagen 0 , Denmark.
Accepted for publication 4 November 1978,
The present investigation is a continuation of an earlier quantitative study (2) o n the ocdusal abrasion by food of restorative resins. In this earlier study the fillings , J , ,,, J were placed m maxillary denture r / porcelain premolars and molars. In the present work all fillings were made in mandibular permanent first natural molars; the aim of the work was to study 1 , , L r j r j , r r , tne abrasion by tood ot diiterent resins, ' ' composite and non-composite, under ordinary physiologic conditions,
Materials and methods The following resinous restorative materials "'^''^^ "^'^ Adaptid* (Johtison & Johnson, New Jersey, U,S,A,), 2) Adaptic without filler, . •' ' . . '^ ^ . ., i,e, a non-composite resm of a similar composition as the resin in the Adaptic composite; the material was furnished by Johnson & Johnson, 3) Sevriton Simplified* (De Trey ^^"0
80 120 AS-75/G2
Discussion
Fig. 4. Abrasion of Adaptic versus AS-75/G2. Each point in the diagram is representative of one pair of fillings of a given patient.
It appears that the development of the composite type of restorative resins was based in part on the philosophy that such resins would show more resistance to the abrasion by different factors in the oral cavity than similar non-composite restoratives. This philosophy has been supported by comprehensive studies (mainly unpublished) in several research laboratories. Since, however, laboratory studies on abrasion frequently are inconclusive for the practical use of the materials involved, the possibility exists thai the abrasion resistance philosophy of the conventional type of composite dental resins is incorrect. The authors of the present work were unable to demonstrate a difference in abrasion by chewing of food between one well-known brand of composite resin (Johnson 8c Johnson's Adaptic) and a similar resin without filler. This finding is
supported by an earlier study (2) in which the composite brand Compocap® made by Ivoclar and a similar resin without filler were used. It should be noted, however, that the rate of abrasion in the present study was higher than in the earlier study in which the fillings were placed in porcelain teeth of full maxillary dentures. Other conclusions of the present investigation that Adaptic with a high degree of probability is abraded less than Sevriton Simplified but more than the micro-Hl! experimental composite AS75/G2, are also supported by the previous study mentioned above. The fact that AS73/G2 was abraded significantly less than Adaptic is possibly explainable by the observation by J0RGENSEN (2} that a distance between neighbor filler particles not exceeding approximately 0,1 fim will
ABRASION OF RESTORATIVE RESIN
prevent food abrasion of the resin component of the composite material. Assuming a uniform distribution of the liiier particles, larger distances berween neighbor filler particles are not liable to occur in the experimental composite in which the diameter of the individual particles is of the order of 25—50 nm. Several other clinical reports are available on the abrasion of resinous restoratives in occlusal cavities (1, 3—S). The abrasion in most of these papers is given in qualitative or relative terms; a comparison with the findings in the present work is therefore hardly possible. Only in the paper by RovLEJet at. (8) and by MEIER SC LUTZ (4) was a quantitative
145
may result in a different classification of the various restorative resins.
References 1. EAMES. W. B., S T S A I N J . D., WEITMAN, R. T.
& WILLIAMS, A. K.: Clinical comparison of composite, amalgam, and silicate restorations./. Am. Dent. Assoc. 1974: 89: 1111-1117 2. J0RGENSE.M, K. D. & AsMtsssEN, E.: Occlusal abrasion of a composite restorative resin with ultra-fine filler - an initial study. Quintessence Int. 1978: 8, No. 6: 73-78 3. LEINFELDER, K. F., SLUDER, T. B., SOCKWELL, C. L., STRICKLA.ND, W . D . & WALL. J. T.:
Clinical evaluation of composite, resins as anterior and posterior restorative materials. J. Prosthet. Dent. 1975:33:407-416
method used which permitted a recording 4. MEIER, C, & LLTZ. F. : Verschleissmessungen ol the abrasion in micrometer per time in vivo an okklusalen Komposit- und Amalgamfulltmgen. Dtich. Zahnaerztl. Z. unit. Since, however, the method of 1978:33:617-622 recording the abrasion in the latter two papers deviates significantly firom that in 5. NucKLES, D. B. Sc FINGAR.W, W.: Six-month and one-year clinical evaluation of a the present work, a detailed statistical composite resin for Class II restorations. / . compariso.n of the results is hardly Am. Dent, .iisoc. 1975:91: 1017-1022 justified; the findings in the two papers, 6. OSBORNE, J. W,, GALE, E. N . SC FERGUSON, G. W.: One-year and two-year clinical on the other hand, do not suggest a disevaluation of a composite resin vs. amalgam. agreement with those reported above. J. Proithet. Dent. 1973:30: 795-800 It should be stressed that the results of 7. PHILLIPS. R. W., AVERY, D . R., MEHRA, R., SWARTZ, M. L, SCMCCU.ME.R.,].: Observations the present work are pertinent only to the on a composite resin for Class 11 restorations: type of abrasion studied, namely chewing Three-year report./, Prosthet. Dent. 1973: 30: ol food without the possibility of direct 891-897 contact between the fillings involved and 8. RouLET, J. F,, METTLER. P. & FRIEDRICH. U, : the corresponding antagonists. Studies on Die Abrasion von Amalgam und Komposits the effect of other oral abrasion factors im Seitenzahnbereich. Dtsch. Zahnaerztl. Z. 1978:33:206-209
