- Email: [email protected]
Current adhesives for indirect bracket bonding
Current adhesives for indirect bracket bonding Elliott
Atlantic
Silverman,
D.D.S.,
and
Morton
City, N. J., and Norristown,
Cohen,
D.D.S.
Pa.
I
n a previous article,s direct bonding of both plastic and metal orthodontic attachments on teeth by the Nuva-Lite, Nuva-Seal system in conjunction with a commercial methyl methacrylate bonding agent was described. The article also illustrated a unique approach for the indirect positioning and bonding of orthodontic brackets on the teeth. A new adhesive has since been developed; it permits even better resulrts with either the direct or the indirect bracket-placement technique. It is not only the superior properties of this adhesive that enchance its success; its physical properties also render it ideal for use in orthodontics. The advantages of this new bonding agent and its method of application, both direct and indirect, are described in this article. Direct
bonding
A detailed explanation of the ultraviolet Nuva-Lite system with the bracketbond adhesive was described previously. Since there have been several changes in the technique, a review of the procedure seems appropriate. The teeth that are to be bonded are first polished with a nonfluoride prophylactic oil-free paste (Fig. 1, A). They are then dried thoroughly and etched for 60 seconds with the tooth conditioner contained in the sealant kit (Fig. 1, A). Water is sprayed over the treated teeth in order to wash away all of the tooth conditioner (Fig. 1? C). The patient must not be permitted to rinse the conditioner off, as this would contaminate the teeth with the mucin in the saliva. It is equally important not to wipe the conditioner away with a wet cotton roll. The teeth are dried again with an air syringe. Care must be taken so that the air in the system is devoid of water or oil droplets. A simple test for this is to blow the air on a mouth mirror. Any foreign substance in the air supply will be deposited on the mirror surface. There are many air-filtering systems that are inexpensive as well as efficient. After air drying, the teeth will appear chalky white (Fig. 1, D) . It is imperative that the teeth remain absolutely dry. 76
Volume Number
65 1
Current
adhesives for
indirect
Fig. 1. A, Teeth are first polished with rubber cup or brush. seconds. C, Water is sprayed to wash away tooth conditioner. drying. E, Nuva-Seal stroked on each tooth. F, Nuva-Lite 20 seconds.
bracket bonding
77
B, Each tooth is etched for 60 D, Teeth chalky-white after (ultraviolet) curing sealant for
The sealant liquid is painted on the surfaces of the teeth that are to be bracketed (Fig. 1, E). After applying a thin coating of sealant, it is important to add several thick droplets of the sealant at the areas where the bonding of the brackets is to occur. The ultraviolet light is then held 1 to 2 mm. from the tooth surface for 20 seconds in order to polymerize the sealant (Fig. 1, P). Excess unpolymerized sealant is allowed to remain on the teeth; it is not removed in this new technique. While strict dryness is maintained, a small portion of the Nuva-Tach adhesive is placed on the posterior surface of each bracket. The brackets are then placed carefully on the teeth in their correct positions. Firm pressure should be exerted on each bracket in order to force the adhesive through the small multiple retentive holes around the periphery of each bracket. This ensures
78
Silverman
Fig. 2. locking
Am. J. Orthocl. Jmuaw 1974
and Cohen
A, Direct placement through the holes.
of bracket onto teeth B, Dental floss to check
showing excess for “bridging.”
Nuva-Tach
adhesive
a mechanical lock between the bracket and the adhesive (Fig. 2, A). Since the adhesive does not set until it is exposed to the shielded ultraviolet rays, each bracket can be properly checked and repositioned in a leisurely manner. Former adhesive techniques required a “hurried” method of application when more than one bracket was involved. This was due to the rapid setting time of the adhesive. If mixtures were made thinner by utilizing a greater liquid-to-powder ratio, the brackets would slide or “float” over the enamel surfaces. The Nuva-Tach adhesive has a thicker consistency, but the most important property of the material is its sensitivity to ultraviolet light. The light, in effect, becomes a catalyst which locks the bracket to the tooth. If excessive adhesive material clogs the bracket channels or tie areas, it can easily be removed with an explorer before application of the light. If it is still present after the ultraviolet light has been applied, it can be removed with a scaler or prophylactic burs. Dental floss is then passed through all interproximal areas to remove any extra adhesive (Fig. 2, 33). Indirect
technique
Placement of unbanded brackets directly on the teeth has probably been the dream of all orthodontists. The results seen thus far with adhesives has finally given hope that this dream may be about to come true. A technique has been developed in which the brackets are first placed on a patient’s plaster casts prior to being transferred to the exact positions on his teeth.
Volume Number
65
1
Current
adhesives
for
indirect
bracket bonding
79
Two sets of models are made for each patient-one for study purposes and the other for use in setting up the case. The prepared brackets are tacked onto the individual plaster teeth in both arches. Brackets are thus placed in their exact positions, since it is done at leisure and with precision. It is not always possible to accomplish this when brackets are bonded directly in the mouth. A plastic tray is formed over the plaster casts. The tray is then removed and the brackets remain embedded within the tray (Fig. 3, A). The teeth are prepared exactly the same as when the direct bonding technique is used. Each bracket in the tray is coated on its lingual surface with a small amount of adhesive. This step may be done carefully, since the material will not be activated to harden until the ultraviolet light is applied (Fig. 3, B) . The tray is then inserted into the mouth and the teeth enter the individual sockets in the plastic tray. Accurate seating of the brackets on their respective teeth is readily seen through the clear plastic used for the tray (Fig. 3, C) . The ultraviolet light is then held over each tooth in the plastic tray for 90 seconds (Fig. 3, D). When all of the adhesive has been activated by the light, the tray is removed. The securely bonded attachments remain in their exact positions (Fig. 3, E, P, and G). Careful examination of each bracket will show surprisingly little or no excess of adhesive around the bracket areas and channels. There also is little excess on the teeth; thus most “bridging” at the contact areas is eliminated. Plastic brackets can also be used. However, these should have one or two small retentive holes drilled through the plastic walls since the bonding involved is strictly mechanical. If any excess does occur, it also is removed with a prophylactic bur in a high-speed handpiece. Two types of toothcontacting area “bridges” can occur. If a sealant is the cause, it can easily be broken with dental floss or a piece of metal stripping. If the adhesive is at fault, it can be removed with a bur. Lingual attachments are placed in the same manner as labial brackets. The most important decision to make before preparing the teeth for the indirect technique is how many brackets can be placed at one time. An effective procedure is to place a mouth prop into position and determine how many teeth can safely be kept dry while the bonding surfaces are being prepared (Fig. 4, A). In certain patients, it is possible to do the entire arch; in others, only the six anterior teeth should be attempted. It is also possible to complete the twelve anterior teeth while inserting two trays simultaneously (Fig. 4, B). Another suggestion is to cut the tray into individual sections and do the posterior segments separately (Fig. 4, C, D, and E). The success seen so far in many of the patients treated seems to indicate that the day of the adhesive has finally arrived. Research may bring a light of greater intensity that will cut the time needed to polymerize both the sealant and the adhesive. Conclusions
Bandless treatment is now available to all who wish to utilize this technique. Tensile strength is exceptional, as proved daily when lingually positioned teeth are ligated into the arch wires without “popping” the brackets away from the
80
&Everman
and Cohen
Fig. 3. A, Clear tray formed on model. B, Brackets coated with adhesive. in mouth. D, Ultraviolet light held on each tooth for approximately 90 Tray being removed. G, Brackets in correct exact positions, including
Am.
J. Orthod.
January
19 7 4
C, Tray inserted seconds. E and F, left buccal tube.
YOlwm? Number
63 1
Current
adhesives for indirect
bracket bonding
Fig. 4. A, Mouth props in position. B and C, Maxillary six anterior teeth done ly with two lights. D, Sectional tray. E and F, Sectional trays in mouth.
simultaneous-
81
Am.
J. Orthod.
Januar~l974
Fig. 5. A and B, Lingual canine-to-canine in sectional tray. D, Adhesive coated. seconds on each tooth. G, Lingual bar
retainer E, Tray in position
bar on model. C, Lingual bar embedded inserted. F, Ultraviolet light held for 90 in mouth.
teeth. Torsion strength is readily apparent when maximum torquing forces on edgewise wires are confidently inserted into the brackets. The time involved in strapping up a complete case is halved with little or no discomfort to the patient and with less stress upon the orthodontist. Separation
Volume Number
65 1
Current
adhesives
for
indirect
bracket bonding
83
Fig.
Rg.
6.
leveling
Fig.
7.
A,
A
typical
wires
A through
edgewise
strap-up
using
all-metal
brackets.
6,
Full
strap-up
with
inserted.
F, Sequence
of
indirect
technique
on
maxillary
arch.
of the teeth is now a thing of the past, and even mandibular canine-to-canine lingual bar retainers can be placed with bonding procedures (Fig. 5, A to a). This article deals primarily with a new indirect system of placing multiple brackets and molar buccal tubes directly upon the individual teeth in both
84
Silverman
and Cohen
Am. J. Orthod. Jamuarz~ 1974
arches (Figs. 6 am3 7). Also described is a new adhesive which has definitely proved successful for lingual attachments as well as the conventional brackets used on labial and buccal surfaces of the teeth. The indirect technique enables the orthodontist to eliminate the laborious and time-consuming procedures of band fitting and cementation. It makes possible a marked increase in patient loads without sacrificing personal and professional ideals, should the government enact a National Health Program. As the times change, so must the orthodontists REFERENCES
1. Newman, G. V.: Epoxy adhesive for orthodontic attachments: Progress report, AM. J. OKTHOD. 50: 901-912,1965. 2. Newman, G. V., Snyder, W. H., and Silson, C. E.: Acrylic adhesives for bonding attachments to tooth surfaces, Angle Orthod. 38: 12-18, 1968. 3. Newman, G. V.: Adhesive and orthodontic plastic attachments, AM. J. ORTHOD. 56: 575-579, 1969. 4. R,etief, D. H., Dryer, C. J., and Gavion, G.: The direct bonding of orthodontic attachments by means of an epoxy resin adhesive, A&I. J. ORTHOD. 58: 21-40, 1970. New direct bonding system for plastic 5. Miura, IF’., Nakagawa, K., and Masuhara, E.: brackets, A&L J. ORTHOD. 59: 350-361, 1971. 6. Buonocore, M. G.: Adhesive sealing of pits and fissures for caries prevention with the use of ultraviolet light, J. Am. Dent. Assoc. 80: 324, 1970. 7. Buonocore, M. G.: Caries prevention in pits and fissures sealed with an adhesive resin A two-year study of a single adhesive application, J. polymerized by ultraviolet light: Am. Dent. Assoc. 82: 1090-1093, 1971. 8. Silverman, E., Cohen, M., Gianelli, Anthony, and Dietz, Victor S.: A universal direct bonding system for both metal and plastic brackets, Ahl. J. ORTHOD. 62: 236-244, 1972.
Atlantic
Silverman,
D.D.S.,
and
Morton
City, N. J., and Norristown,
Cohen,
D.D.S.
Pa.
I
n a previous article,s direct bonding of both plastic and metal orthodontic attachments on teeth by the Nuva-Lite, Nuva-Seal system in conjunction with a commercial methyl methacrylate bonding agent was described. The article also illustrated a unique approach for the indirect positioning and bonding of orthodontic brackets on the teeth. A new adhesive has since been developed; it permits even better resulrts with either the direct or the indirect bracket-placement technique. It is not only the superior properties of this adhesive that enchance its success; its physical properties also render it ideal for use in orthodontics. The advantages of this new bonding agent and its method of application, both direct and indirect, are described in this article. Direct
bonding
A detailed explanation of the ultraviolet Nuva-Lite system with the bracketbond adhesive was described previously. Since there have been several changes in the technique, a review of the procedure seems appropriate. The teeth that are to be bonded are first polished with a nonfluoride prophylactic oil-free paste (Fig. 1, A). They are then dried thoroughly and etched for 60 seconds with the tooth conditioner contained in the sealant kit (Fig. 1, A). Water is sprayed over the treated teeth in order to wash away all of the tooth conditioner (Fig. 1? C). The patient must not be permitted to rinse the conditioner off, as this would contaminate the teeth with the mucin in the saliva. It is equally important not to wipe the conditioner away with a wet cotton roll. The teeth are dried again with an air syringe. Care must be taken so that the air in the system is devoid of water or oil droplets. A simple test for this is to blow the air on a mouth mirror. Any foreign substance in the air supply will be deposited on the mirror surface. There are many air-filtering systems that are inexpensive as well as efficient. After air drying, the teeth will appear chalky white (Fig. 1, D) . It is imperative that the teeth remain absolutely dry. 76
Volume Number
65 1
Current
adhesives for
indirect
Fig. 1. A, Teeth are first polished with rubber cup or brush. seconds. C, Water is sprayed to wash away tooth conditioner. drying. E, Nuva-Seal stroked on each tooth. F, Nuva-Lite 20 seconds.
bracket bonding
77
B, Each tooth is etched for 60 D, Teeth chalky-white after (ultraviolet) curing sealant for
The sealant liquid is painted on the surfaces of the teeth that are to be bracketed (Fig. 1, E). After applying a thin coating of sealant, it is important to add several thick droplets of the sealant at the areas where the bonding of the brackets is to occur. The ultraviolet light is then held 1 to 2 mm. from the tooth surface for 20 seconds in order to polymerize the sealant (Fig. 1, P). Excess unpolymerized sealant is allowed to remain on the teeth; it is not removed in this new technique. While strict dryness is maintained, a small portion of the Nuva-Tach adhesive is placed on the posterior surface of each bracket. The brackets are then placed carefully on the teeth in their correct positions. Firm pressure should be exerted on each bracket in order to force the adhesive through the small multiple retentive holes around the periphery of each bracket. This ensures
78
Silverman
Fig. 2. locking
Am. J. Orthocl. Jmuaw 1974
and Cohen
A, Direct placement through the holes.
of bracket onto teeth B, Dental floss to check
showing excess for “bridging.”
Nuva-Tach
adhesive
a mechanical lock between the bracket and the adhesive (Fig. 2, A). Since the adhesive does not set until it is exposed to the shielded ultraviolet rays, each bracket can be properly checked and repositioned in a leisurely manner. Former adhesive techniques required a “hurried” method of application when more than one bracket was involved. This was due to the rapid setting time of the adhesive. If mixtures were made thinner by utilizing a greater liquid-to-powder ratio, the brackets would slide or “float” over the enamel surfaces. The Nuva-Tach adhesive has a thicker consistency, but the most important property of the material is its sensitivity to ultraviolet light. The light, in effect, becomes a catalyst which locks the bracket to the tooth. If excessive adhesive material clogs the bracket channels or tie areas, it can easily be removed with an explorer before application of the light. If it is still present after the ultraviolet light has been applied, it can be removed with a scaler or prophylactic burs. Dental floss is then passed through all interproximal areas to remove any extra adhesive (Fig. 2, 33). Indirect
technique
Placement of unbanded brackets directly on the teeth has probably been the dream of all orthodontists. The results seen thus far with adhesives has finally given hope that this dream may be about to come true. A technique has been developed in which the brackets are first placed on a patient’s plaster casts prior to being transferred to the exact positions on his teeth.
Volume Number
65
1
Current
adhesives
for
indirect
bracket bonding
79
Two sets of models are made for each patient-one for study purposes and the other for use in setting up the case. The prepared brackets are tacked onto the individual plaster teeth in both arches. Brackets are thus placed in their exact positions, since it is done at leisure and with precision. It is not always possible to accomplish this when brackets are bonded directly in the mouth. A plastic tray is formed over the plaster casts. The tray is then removed and the brackets remain embedded within the tray (Fig. 3, A). The teeth are prepared exactly the same as when the direct bonding technique is used. Each bracket in the tray is coated on its lingual surface with a small amount of adhesive. This step may be done carefully, since the material will not be activated to harden until the ultraviolet light is applied (Fig. 3, B) . The tray is then inserted into the mouth and the teeth enter the individual sockets in the plastic tray. Accurate seating of the brackets on their respective teeth is readily seen through the clear plastic used for the tray (Fig. 3, C) . The ultraviolet light is then held over each tooth in the plastic tray for 90 seconds (Fig. 3, D). When all of the adhesive has been activated by the light, the tray is removed. The securely bonded attachments remain in their exact positions (Fig. 3, E, P, and G). Careful examination of each bracket will show surprisingly little or no excess of adhesive around the bracket areas and channels. There also is little excess on the teeth; thus most “bridging” at the contact areas is eliminated. Plastic brackets can also be used. However, these should have one or two small retentive holes drilled through the plastic walls since the bonding involved is strictly mechanical. If any excess does occur, it also is removed with a prophylactic bur in a high-speed handpiece. Two types of toothcontacting area “bridges” can occur. If a sealant is the cause, it can easily be broken with dental floss or a piece of metal stripping. If the adhesive is at fault, it can be removed with a bur. Lingual attachments are placed in the same manner as labial brackets. The most important decision to make before preparing the teeth for the indirect technique is how many brackets can be placed at one time. An effective procedure is to place a mouth prop into position and determine how many teeth can safely be kept dry while the bonding surfaces are being prepared (Fig. 4, A). In certain patients, it is possible to do the entire arch; in others, only the six anterior teeth should be attempted. It is also possible to complete the twelve anterior teeth while inserting two trays simultaneously (Fig. 4, B). Another suggestion is to cut the tray into individual sections and do the posterior segments separately (Fig. 4, C, D, and E). The success seen so far in many of the patients treated seems to indicate that the day of the adhesive has finally arrived. Research may bring a light of greater intensity that will cut the time needed to polymerize both the sealant and the adhesive. Conclusions
Bandless treatment is now available to all who wish to utilize this technique. Tensile strength is exceptional, as proved daily when lingually positioned teeth are ligated into the arch wires without “popping” the brackets away from the
80
&Everman
and Cohen
Fig. 3. A, Clear tray formed on model. B, Brackets coated with adhesive. in mouth. D, Ultraviolet light held on each tooth for approximately 90 Tray being removed. G, Brackets in correct exact positions, including
Am.
J. Orthod.
January
19 7 4
C, Tray inserted seconds. E and F, left buccal tube.
YOlwm? Number
63 1
Current
adhesives for indirect
bracket bonding
Fig. 4. A, Mouth props in position. B and C, Maxillary six anterior teeth done ly with two lights. D, Sectional tray. E and F, Sectional trays in mouth.
simultaneous-
81
Am.
J. Orthod.
Januar~l974
Fig. 5. A and B, Lingual canine-to-canine in sectional tray. D, Adhesive coated. seconds on each tooth. G, Lingual bar
retainer E, Tray in position
bar on model. C, Lingual bar embedded inserted. F, Ultraviolet light held for 90 in mouth.
teeth. Torsion strength is readily apparent when maximum torquing forces on edgewise wires are confidently inserted into the brackets. The time involved in strapping up a complete case is halved with little or no discomfort to the patient and with less stress upon the orthodontist. Separation
Volume Number
65 1
Current
adhesives
for
indirect
bracket bonding
83
Fig.
Rg.
6.
leveling
Fig.
7.
A,
A
typical
wires
A through
edgewise
strap-up
using
all-metal
brackets.
6,
Full
strap-up
with
inserted.
F, Sequence
of
indirect
technique
on
maxillary
arch.
of the teeth is now a thing of the past, and even mandibular canine-to-canine lingual bar retainers can be placed with bonding procedures (Fig. 5, A to a). This article deals primarily with a new indirect system of placing multiple brackets and molar buccal tubes directly upon the individual teeth in both
84
Silverman
and Cohen
Am. J. Orthod. Jamuarz~ 1974
arches (Figs. 6 am3 7). Also described is a new adhesive which has definitely proved successful for lingual attachments as well as the conventional brackets used on labial and buccal surfaces of the teeth. The indirect technique enables the orthodontist to eliminate the laborious and time-consuming procedures of band fitting and cementation. It makes possible a marked increase in patient loads without sacrificing personal and professional ideals, should the government enact a National Health Program. As the times change, so must the orthodontists REFERENCES
1. Newman, G. V.: Epoxy adhesive for orthodontic attachments: Progress report, AM. J. OKTHOD. 50: 901-912,1965. 2. Newman, G. V., Snyder, W. H., and Silson, C. E.: Acrylic adhesives for bonding attachments to tooth surfaces, Angle Orthod. 38: 12-18, 1968. 3. Newman, G. V.: Adhesive and orthodontic plastic attachments, AM. J. ORTHOD. 56: 575-579, 1969. 4. R,etief, D. H., Dryer, C. J., and Gavion, G.: The direct bonding of orthodontic attachments by means of an epoxy resin adhesive, A&I. J. ORTHOD. 58: 21-40, 1970. New direct bonding system for plastic 5. Miura, IF’., Nakagawa, K., and Masuhara, E.: brackets, A&L J. ORTHOD. 59: 350-361, 1971. 6. Buonocore, M. G.: Adhesive sealing of pits and fissures for caries prevention with the use of ultraviolet light, J. Am. Dent. Assoc. 80: 324, 1970. 7. Buonocore, M. G.: Caries prevention in pits and fissures sealed with an adhesive resin A two-year study of a single adhesive application, J. polymerized by ultraviolet light: Am. Dent. Assoc. 82: 1090-1093, 1971. 8. Silverman, E., Cohen, M., Gianelli, Anthony, and Dietz, Victor S.: A universal direct bonding system for both metal and plastic brackets, Ahl. J. ORTHOD. 62: 236-244, 1972.