Esthetic Arch Bar in Orthognathic Surgery
have shown better clinical performance. This hypothesis is supported by the study of Hdrsted-Bindslevet a19who found that so-called miniwed composite resins performed significantlybetter with regard to marginal fractures and marginal discoloration than microfilled composite resins when the tillingswere placed in nonundercut cervical erosion lesions and retained with dentin and enamel bonding agents. The new adhesive material tested is a clinically promising agent that seems to mediate an adequate bond to enamel and even to dentin. To substantiate the validity of the in uiuo/in uitro method used, further research involvinga larger number of teeth and different adhesive restorative systems is in progress.
3. BrSnnstr6rn M. Composite resin restorations: biological considerations with special reference to dentin and pulp. In: Vanherle G, Smith DC, eds. Posterior composite resin dental restorative materials. Netherlands: Peter Szulc 1985, 7-8. 4. Torstenson B, NordenvalJ KJ, B r h s t r 6 m M. Pulpal reaction and microorganisms under C l e m composite resin in deep cavities with acid etched dentin. Swed Dent J 1982; 56-176. 5. Triadan H. When is microleakage a real clinical problem? Operat Dent 1987; 12:153-157. 6. Kubo S. Finger WJ, Mtiller M, Podszun W. Principles and mechanisms of bonding with dentin adhesive materials. J Esthet Dent 1991; 2:62-69. 7. S6derholmKJM. Correlationofinvivo andinvitro performance of adhesive restorative materials: a report of the ASC MD 156 Task Group on Test Methods for the Adhesion of Restorative Materials. Dent Mater 1991; 7:74-83. 8. Rueggeberg FA. Substrate for adhesion testing to tooth structure-review of the literature. Dent Mater 1991; 7: 2-10. 9. HBrsted-BindslevP, Knudsen J. Baelum V. Dentin adhesive materials for restoration of cervical erosions. Two and three year clinical observations. Am J Dent 1988: 1:195199.
REFERENCES 1. Torstenson B. Oden A. Effects of bonding agent types and incremental techniques on ' . . i g contraction gaps around resin composites. Dent Mater 1989; 5:21&223. 2. Finger WJ. Dentin bonding agents. Relevance of in vitro investigations. Am J Dent 1988; 1:184-188.
Esthetic Arch Bar for Maxillomandibular Fixation in Orthognathic Surgery Fun-Chee Loh, B.D.S., MB.S., MSc., F.A.M.S.," Kenneth K.K. Lew, B.D.S., M.D.S., FA.M.S.,t and Chee-Hwee Sim
Arch bars are well-known dental appliances for the management of fractures and orthognathic surgery. Traditionally both the commercially available, prefabricated arch bars as well as the custom-made arch bars are made of metal so as to provide good rigidity. Each of these types of arch bars has its own advantages as well as drawbacks. This article looks at a type of custom-made arch bar that is easy to construct and use. At the same time, it provides good rigidity, fit, and esthetics.
T
cause these metallic arch bars provide a precise fit onto the dentition, they are useful for localizing segments of the dental arches. Because the majorityof patients seeking orthognathic surgery for dentofacial deformities are adults who are well aware of esthetics, we have developed an arch bar that is made of self-curing clear acrylic resin that provides good rigidity, precise fit, and at the same time is esthetically acceptable.
for maintaMng the dental he use of arch arches in the management offractures and for maxfflomandibular fixationin orthognathic surgery is a wellestablished practice. Prefabricated arch bars are easily obtainable commercially and, unlike the custom-made arch bars, do not require any laboratory procedure. Custom-made arch bars suffer from the d u d disadvantages of requiring rather sophisticated laboratory support and of esthetic unacceptability. Nevertheless, be-
35
JOURNAL.OF ESTHETIC DENTISTRY VOLUME 4, SUPPLEMENT 1992
Figure 1. Half-round3.5mmdentalwaxadaptedtothedentd arch. Cleats for maxillomandibularfuration added at the appropriate locations.
Figure 3. Cross-sectional view of the tooth and arch bar showing the funnel-shaped passage throughwhich the tie wire passes.
TECHNIQUE A strip of dental wax 3.5 mm wide and 2 mm thick is adapted to the cenical third of the labial surfaces of the teeth. The wax may be warmed to achieve closer adaptation. More wax is added along the middle part of the strip of wax to achieve a half-round cross-sectional profile. Cleats for maxillomandibular fmation are added at the appropriate locations (Fig. 1). The wax is then smoothed so that the final splint does not require too much trimming. Separating medium is then applied to the plaster cast, which is then invested in plaster of Paris. The investing plaster covers
the wax but leaves the top margin uncovered (Fig. 2).The wax is then completely and carefully boiled out. Self-cureacrylic is then used by means of a salt and pepper technique to fill the space left by the boiled-out Wax. The cast is then put into a Hydroflask pressure pot for curing. After curing for 15 minutes, the investing plaster of Paris is removed and the splint is lightly polished to a smooth finish. Using a small round bur, holes are made a t points corresponding to the interproximal spaces of the dentition. On the side of the arch bar that adapts to the dentition, a larger round bur is used to widen the holes. This in effect creates a funnel, which helps to channel the tie wire through the holes easily while the arch bar is being tied to the teeth (Fig.3).
DISCUSSION The essential features of this type of arch bar are as follows: cross-sectionally the arch bar is half-round and has awidth of3.5 mm. thus providingwidercontactwith tooth surfaces and minimizing rotation of the jaw fragments. Since it is made of acrylic and is therefore slightly flexible, undercuts at the interproximal areas need not
Figure 2. Plaster cast invested in plaster of Paris leaving the top part of the wax pattern uncovered.
'Consultant. Department of Oral and Maxillofacial Surgery: t Senior Lecturer In Orthodontics. Department of Preventive Dentistry: and *Dental Technologist;National University of Singapore, Faculty of Dentistry, Singapore Address reprint requests to Dr. F.C. Loh. Department of Oral and Maxillofacial Surgery. Faculty of Dentistry, National University of Singapore. National University Hospital, Lower Kent Ridge Road. Singapore 051 1 0 1992 Decker Perlodicals Inc.
Figure 4. Esthetic arch bar in a patient.
36
Effect of Dentinal Adhesives on Marginal Adaptation
be eliminated for the arch bar to be fitted. This provides closer adaptation of the arch bar to the dentition and hence avoids tooth movement. Unlike other arch bars that require the tie wire to go above and then below the arch bar in order to secure the arch bar to the dentition, the arch bar described here makes use of tie wires that go through the arch bar. This makes the tying procedure easy, and it introduces no torque to the dentition since the wires are not tied obliquely. The "funneling" of the holes through which the tie wires pass also makes it easy to thread the wire from the lingual side to the buccal side of the arch bar. The use of clear acrylic in the construction of this arch bar renders it esthetically more acceptable (Fig.4). In patients who are treated with lingual orthodontics3in preparation for orthognathic surgery, the use of esthetic arch bar complements the "invisible" braces. In the minority of orthognathic surgery patients who do not require presurgical orthodontics, the use of esthetic arch bars reduces the unsightliness of the metallic arch bars during the period of maxillomandibular furation and arch stabilization prior to postsurgical orthodontics.
CONCLUSION A newly designed arch bar has been described that is esthetically acceptable. Furthermore, the new arch bar provides ease in application for patients who require an arch bar for maxillomandibular furation.
REFERENCES 1.
Rowe NL. Williams JLL. Maxillofacial injuries. Edinburgh: Churchill Livingstone, 1985. 2. Fujita K. New orthodontic treatment with lingual mushroom archwire appliance. Am J Orthod 1979;76:657-675. 3. Kelly VM. Lingual orthodontics. J Clin Orthod 1982; 16:461-476. 4. Creekmore T. Lingual orthodontics - its renaissance. Am J Orthod Dentofac Orthop 1989; 96:12&137. 5. Moody C,Alexander RG, G o m a n J C , et al. Lingual orthodontics : a status report. J Clin Orthod 1982;16:255-262.
Effect of Dentinal Adhesives on Marginal Adaptation and Cavity Sealing with Resin Restorations In Vitro Shisei Kubo, D.D.S., Ph.D.,* Werner J . Finger, D.M.D., Ph.D.J Michael Miiller, Dr. rer. nut.) Wolfgang Podszun, Dr. rer. nat.?and Hans F. Walter, Dr. rer. nat.§
In a companion article in this issue and a previous article in this journal, two experimental enamel dentin adhesive systems were evaluated and compared with four commercially available resin bonding agents by SEM investigation of the tooth adhesive interfaces and by determination of bond strengths to enamel and dentin under various conditions. In continuation of these screening investigations, the present article describes the results of cavity tests for assessment of marginal adaptation by measurement of gap dimensions, and of cavity sealing by rating of microleakage, when standardized dentin cavities were treated with the adhesive restorative systems. Both tests resulted in the same ranking of the six materials. Gluma, C l e d Photo Bond, and two experimental compounds showed very narrow gaps and moderate microleakage. In contrast, prisma Universal Bond 2 (the material has been replaced in the market by prisma Universal Bond 3)and Scotchbond 2 showed significantlywider marginal gaps and more pronounced microleakage. Final discrimination between the efficacy of adhesive restorative materials by any of the currently used in uftro tests is disputable and prediction of long-term clinical performance by laboratory test data remains questionable.
37
have shown better clinical performance. This hypothesis is supported by the study of Hdrsted-Bindslevet a19who found that so-called miniwed composite resins performed significantlybetter with regard to marginal fractures and marginal discoloration than microfilled composite resins when the tillingswere placed in nonundercut cervical erosion lesions and retained with dentin and enamel bonding agents. The new adhesive material tested is a clinically promising agent that seems to mediate an adequate bond to enamel and even to dentin. To substantiate the validity of the in uiuo/in uitro method used, further research involvinga larger number of teeth and different adhesive restorative systems is in progress.
3. BrSnnstr6rn M. Composite resin restorations: biological considerations with special reference to dentin and pulp. In: Vanherle G, Smith DC, eds. Posterior composite resin dental restorative materials. Netherlands: Peter Szulc 1985, 7-8. 4. Torstenson B, NordenvalJ KJ, B r h s t r 6 m M. Pulpal reaction and microorganisms under C l e m composite resin in deep cavities with acid etched dentin. Swed Dent J 1982; 56-176. 5. Triadan H. When is microleakage a real clinical problem? Operat Dent 1987; 12:153-157. 6. Kubo S. Finger WJ, Mtiller M, Podszun W. Principles and mechanisms of bonding with dentin adhesive materials. J Esthet Dent 1991; 2:62-69. 7. S6derholmKJM. Correlationofinvivo andinvitro performance of adhesive restorative materials: a report of the ASC MD 156 Task Group on Test Methods for the Adhesion of Restorative Materials. Dent Mater 1991; 7:74-83. 8. Rueggeberg FA. Substrate for adhesion testing to tooth structure-review of the literature. Dent Mater 1991; 7: 2-10. 9. HBrsted-BindslevP, Knudsen J. Baelum V. Dentin adhesive materials for restoration of cervical erosions. Two and three year clinical observations. Am J Dent 1988: 1:195199.
REFERENCES 1. Torstenson B. Oden A. Effects of bonding agent types and incremental techniques on ' . . i g contraction gaps around resin composites. Dent Mater 1989; 5:21&223. 2. Finger WJ. Dentin bonding agents. Relevance of in vitro investigations. Am J Dent 1988; 1:184-188.
Esthetic Arch Bar for Maxillomandibular Fixation in Orthognathic Surgery Fun-Chee Loh, B.D.S., MB.S., MSc., F.A.M.S.," Kenneth K.K. Lew, B.D.S., M.D.S., FA.M.S.,t and Chee-Hwee Sim
Arch bars are well-known dental appliances for the management of fractures and orthognathic surgery. Traditionally both the commercially available, prefabricated arch bars as well as the custom-made arch bars are made of metal so as to provide good rigidity. Each of these types of arch bars has its own advantages as well as drawbacks. This article looks at a type of custom-made arch bar that is easy to construct and use. At the same time, it provides good rigidity, fit, and esthetics.
T
cause these metallic arch bars provide a precise fit onto the dentition, they are useful for localizing segments of the dental arches. Because the majorityof patients seeking orthognathic surgery for dentofacial deformities are adults who are well aware of esthetics, we have developed an arch bar that is made of self-curing clear acrylic resin that provides good rigidity, precise fit, and at the same time is esthetically acceptable.
for maintaMng the dental he use of arch arches in the management offractures and for maxfflomandibular fixationin orthognathic surgery is a wellestablished practice. Prefabricated arch bars are easily obtainable commercially and, unlike the custom-made arch bars, do not require any laboratory procedure. Custom-made arch bars suffer from the d u d disadvantages of requiring rather sophisticated laboratory support and of esthetic unacceptability. Nevertheless, be-
35
JOURNAL.OF ESTHETIC DENTISTRY VOLUME 4, SUPPLEMENT 1992
Figure 1. Half-round3.5mmdentalwaxadaptedtothedentd arch. Cleats for maxillomandibularfuration added at the appropriate locations.
Figure 3. Cross-sectional view of the tooth and arch bar showing the funnel-shaped passage throughwhich the tie wire passes.
TECHNIQUE A strip of dental wax 3.5 mm wide and 2 mm thick is adapted to the cenical third of the labial surfaces of the teeth. The wax may be warmed to achieve closer adaptation. More wax is added along the middle part of the strip of wax to achieve a half-round cross-sectional profile. Cleats for maxillomandibular fmation are added at the appropriate locations (Fig. 1). The wax is then smoothed so that the final splint does not require too much trimming. Separating medium is then applied to the plaster cast, which is then invested in plaster of Paris. The investing plaster covers
the wax but leaves the top margin uncovered (Fig. 2).The wax is then completely and carefully boiled out. Self-cureacrylic is then used by means of a salt and pepper technique to fill the space left by the boiled-out Wax. The cast is then put into a Hydroflask pressure pot for curing. After curing for 15 minutes, the investing plaster of Paris is removed and the splint is lightly polished to a smooth finish. Using a small round bur, holes are made a t points corresponding to the interproximal spaces of the dentition. On the side of the arch bar that adapts to the dentition, a larger round bur is used to widen the holes. This in effect creates a funnel, which helps to channel the tie wire through the holes easily while the arch bar is being tied to the teeth (Fig.3).
DISCUSSION The essential features of this type of arch bar are as follows: cross-sectionally the arch bar is half-round and has awidth of3.5 mm. thus providingwidercontactwith tooth surfaces and minimizing rotation of the jaw fragments. Since it is made of acrylic and is therefore slightly flexible, undercuts at the interproximal areas need not
Figure 2. Plaster cast invested in plaster of Paris leaving the top part of the wax pattern uncovered.
'Consultant. Department of Oral and Maxillofacial Surgery: t Senior Lecturer In Orthodontics. Department of Preventive Dentistry: and *Dental Technologist;National University of Singapore, Faculty of Dentistry, Singapore Address reprint requests to Dr. F.C. Loh. Department of Oral and Maxillofacial Surgery. Faculty of Dentistry, National University of Singapore. National University Hospital, Lower Kent Ridge Road. Singapore 051 1 0 1992 Decker Perlodicals Inc.
Figure 4. Esthetic arch bar in a patient.
36
Effect of Dentinal Adhesives on Marginal Adaptation
be eliminated for the arch bar to be fitted. This provides closer adaptation of the arch bar to the dentition and hence avoids tooth movement. Unlike other arch bars that require the tie wire to go above and then below the arch bar in order to secure the arch bar to the dentition, the arch bar described here makes use of tie wires that go through the arch bar. This makes the tying procedure easy, and it introduces no torque to the dentition since the wires are not tied obliquely. The "funneling" of the holes through which the tie wires pass also makes it easy to thread the wire from the lingual side to the buccal side of the arch bar. The use of clear acrylic in the construction of this arch bar renders it esthetically more acceptable (Fig.4). In patients who are treated with lingual orthodontics3in preparation for orthognathic surgery, the use of esthetic arch bar complements the "invisible" braces. In the minority of orthognathic surgery patients who do not require presurgical orthodontics, the use of esthetic arch bars reduces the unsightliness of the metallic arch bars during the period of maxillomandibular furation and arch stabilization prior to postsurgical orthodontics.
CONCLUSION A newly designed arch bar has been described that is esthetically acceptable. Furthermore, the new arch bar provides ease in application for patients who require an arch bar for maxillomandibular furation.
REFERENCES 1.
Rowe NL. Williams JLL. Maxillofacial injuries. Edinburgh: Churchill Livingstone, 1985. 2. Fujita K. New orthodontic treatment with lingual mushroom archwire appliance. Am J Orthod 1979;76:657-675. 3. Kelly VM. Lingual orthodontics. J Clin Orthod 1982; 16:461-476. 4. Creekmore T. Lingual orthodontics - its renaissance. Am J Orthod Dentofac Orthop 1989; 96:12&137. 5. Moody C,Alexander RG, G o m a n J C , et al. Lingual orthodontics : a status report. J Clin Orthod 1982;16:255-262.
Effect of Dentinal Adhesives on Marginal Adaptation and Cavity Sealing with Resin Restorations In Vitro Shisei Kubo, D.D.S., Ph.D.,* Werner J . Finger, D.M.D., Ph.D.J Michael Miiller, Dr. rer. nut.) Wolfgang Podszun, Dr. rer. nat.?and Hans F. Walter, Dr. rer. nat.§
In a companion article in this issue and a previous article in this journal, two experimental enamel dentin adhesive systems were evaluated and compared with four commercially available resin bonding agents by SEM investigation of the tooth adhesive interfaces and by determination of bond strengths to enamel and dentin under various conditions. In continuation of these screening investigations, the present article describes the results of cavity tests for assessment of marginal adaptation by measurement of gap dimensions, and of cavity sealing by rating of microleakage, when standardized dentin cavities were treated with the adhesive restorative systems. Both tests resulted in the same ranking of the six materials. Gluma, C l e d Photo Bond, and two experimental compounds showed very narrow gaps and moderate microleakage. In contrast, prisma Universal Bond 2 (the material has been replaced in the market by prisma Universal Bond 3)and Scotchbond 2 showed significantlywider marginal gaps and more pronounced microleakage. Final discrimination between the efficacy of adhesive restorative materials by any of the currently used in uftro tests is disputable and prediction of long-term clinical performance by laboratory test data remains questionable.
37
