- Email: [email protected]
Direct method of registering periimplant soft tissue forms for implant-supported fixed dental prostheses
DENTAL TECHNIQUE
Direct method of registering periimplant soft tissue forms for implant-supported fixed dental prostheses Karl E. Hegyi, DDS The form and health of periABSTRACT implant and pontic site tissues This article describes a direct technique for communicating implant abutment and pontic intaglio are critical for the esthetic surface forms with the dental laboratory. The technique uses a matrix and a screw-retained custom success of implant-supported interim restoration. The matrix is used to transfer the interim restoration and periimplant tissue restorations. Key factors affforms from the patient’s mouth to an implant position-verified cast. After being connected to this ecting these qualities are the cast, a silicone soft tissue replicating material is injected into the matrix. The result is a definitive cast with accurate implant position and soft tissue forms. (J Prosthet Dent 2015;-:---) abutment emergence (the subgingival portion of the restorestoration abutment and the definitive cast is poured. ration between the implant platform and gingival Concerns with this technique include the accuracy of the margin) and pontic intaglio surface forms.1-4 For the most predictable outcome, these forms should be developed implant position in the cast (dependent upon temporary with a custom interim restoration before definitive cylinder to implant analog fit) and the need to immediately pour the definitive cast after making the impression restoration.1-4 Once perfected in the interim restoration, (in order to return the interim restoration to the patient).7 they must be accurately communicated with the laboraThe second technique uses an in situ registration of tory. The purpose of this article is to describe a the interim restoration and surrounding tissues. The straightforward yet accurate method for doing this. registration and interim restoration are separately Because of the circumferential arrangement of removed from the mouth and then transferred to a collagen fibers in supracrestal periimplant tissues, their form rapidly changes when an interim restoration is previously made cast of the integrated implants. Comremoved to make an impression.5 In addition, the pontic bined with a silicone gingival material, the cast is modified to replicate soft tissue detail and becomes the site tissue form may change.3 Therefore, simply removing definitive cast.8,9 the interim restoration and using a standard fixture level The described technique is similar to this second implant impression technique is not acceptable. direct type. However, it differs from the above referenced Direct and indirect methods have been used to methods in 2 important ways: the method and materials overcome this problem. Indirect techniques involve of in situ soft tissue registration, and the method of fabricating custom impression copings to maintain the soft tissue forms developed with the interim restoration transferring this registration for definitive cast fabrication. during the impression.6 Concerns with this technique The advantages of these differences are improved accuracy and increased detail of the periimplant tissue repliinclude the time and cost required to fabricate these cation on the definitive cast. custom copings. Before implementing the technique, 2 conventional Direct techniques use the refined interim restoration dental procedures are required. The first is a fixture level to record periimplant tissue forms. These techniques fall impression made any time after implant primary stability. into 3 major types. The first uses the interim restoration The second is a screw-retained custom interim restoraas the impression coping.1,7 After making the impression, tion. In the treatment illustrated in this article, this an implant laboratory analog is attached to the interim Private practice, Strongsville, Ohio.
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Figure 1. Interim cast used to fabricate interim restoration and verify implant analog positions.
Figure 2. Interim cast with silicone soft tissue replicating material removed, exposing verified implant analogs and silicone injection ports.
Figure 3. Silicone injection port access openings.
Figure 4. Matrix with screw access channel dowel pins in place.
involved a custom, open tray impression (Triad TruTray Custom Tray Material; Dentsply Intl, 3.5 and 4.0 mm Open Tray Impression Copings; Thommen Medical, Panasil Initial Contact Light; Kettenbach) and a 1-piece splinted screw-retained interim restoration (3.5 and 4.0 mm Temporary Abutments; Thommen Medical, PMMA Acrylic; Huge Dental Material Co Ltd). The interim restoration was fabricated indirectly on a cast (CAD Rock; Nobilium Co, GI-MASK; Coltène/Whaledent) made from this open tray impression. The interim restoration was seated and abutment customization began 4 weeks after implant placement. In addition to these procedures, the proposed technique requires that the cast be verified to represent the definitive position and timing of the dental implants (the splinted interim restoration may be used for this purpose); accurately represent the form of all remaining teeth and restorations in that arch; and have a removable silicone soft tissue replicating material (GI-MASK; Coltène/Whaledent) represent the periimplant and pontic site soft tissue forms (Fig. 1). If these 3 requirements are met, the only difference between this cast and that required to fabricate the definitive restoration involves periimplant and pontic site soft tissue forms. Therefore, once such a cast is made (hereafter referred to as the
interim cast), it need only be modified to represent these definitive soft tissue forms for it to serve as the definitive cast. The proposed technique involves this process of modification. Although the technique is illustrated in a treatment involving 3 partial fixed dental prostheses, it may also be applied to single or multiple individual implant restorations.
THE JOURNAL OF PROSTHETIC DENTISTRY
TECHNIQUE Once implant integration is complete and the interim restoration and soft tissue forms are determined, make an accurate irreversible hydrocolloid impression (Jeltrate; Dentsply Caulk) and cast (Coe Cal; GC America) (Abrahamsen TC, “Accurate diagnostic casts from the sophisticated alginate impression-through the eyes of the master,” DVD, American Academy of Restorative Dentistry, 1999) of the involved arch. The location of the interim restoration screw access channels should be visible on this cast. 1. Fabricate a clear flexible matrix (Thermo-Forming Material Clear-Mouthguard 15000 ; Henry Schein Inc) over this cast. Remove the silicone soft tissue replicating material from the interim cast (Fig. 2). Hegyi
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2015
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Figure 5. Matrix with encased interim implant restoration (and interim first molar crown) in polyvinyl siloxane soft tissue impression.
Figure 6. Matrix connected to interim cast after silicone injection.
Figure 7. Former interim cast after new silicone injection. This is now definitive cast.
Figure 8. Definitive restorations immediately after seating.
Trim the vestibular extension of the matrix to that of the removed silicone. If necessary, relieve soft tissue areas of the interim cast or trim the matrix so that the matrix can be completely seated without interference. Referencing the cast from step 1, drill holes through the matrix (H-219s Port Bur; Brassler USA) to allow access to the screw access channels. 2. Drill an injection port (H-219s Port Bur; Brassler USA) mesial and distal to each implant on the interim cast. These ports should communicate between a portion of the cast not covered by the matrix and the area previously occupied by the silicone soft tissue replicating material (Figs. 2, 3). 3. At the soft tissue registration appointment, clean the interim restoration screw-access channels to allow the screwdriver to engage the abutment screws. Place the matrix in the mouth and verify that the screwdriver can still engage the abutment screws through the matrix. If necessary, enlarge the holes in the matrix. 4. Remove the matrix and place appropriate diameter dowel pins (Project 70 Stainless Type 303; Carpenter Technology Corp) to obturate the abutment screw-access channels (1.5 mm for Thommen 3.5 Hegyi
mm and 1.8 mm for Thommen 4.0 provisional abutments). The dowel pins should be long enough to extend approximately 4 to 5 mm beyond the access channel openings. Confirm that with the dowel pins in place the matrix can still be fully seated over the interim restoration without interference (Fig. 4). (If interarch space permits, laboratory fabrication screws may be used in place of the abutment screws and dowel pins in this and subsequent steps.) 5. With dowel pins in the access channels, inject impression material (Coe Syringe; GC America Inc, Panasil Initial Contact Light; Kettenbach) around the soft tissue surrounding the interim restoration, and seat the matrix. It is important that the matrix, impression material, and interim restoration not separate during the following step. If necessary, a small amount of adhesive (Universal VPS Adhesive; GC America) may be applied to the interim restoration and matrix. Once the impression material is set, remove the dowel pins, loosen the abutment screws, and remove the matrix (along with the encased interim restoration and soft tissue impression) (Fig. 5). THE JOURNAL OF PROSTHETIC DENTISTRY
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6. Spray the tissue side of the matrix with a release agent (Lang Silicone Spray; Lang Dental Mfg Co) and connect the matrix (containing the encased interim restoration and soft tissue impression) to the interim cast. Tighten the abutment screws of the interim restoration enough to ensure that the interim restoration is completely seated into the implant analogs. 7. Sequentially inject silicone soft tissue replicating material (GI-MASK; Coltène/Whaledent) into each port until excess material extrudes through the next port (Fig. 6). 8. Upon setting of the silicone soft tissue replicating material, loosen the interim abutment screws and remove the matrix. An accurate registration of the interim abutments, periimplant, and pontic site tissue forms are now represented on the interim cast. At this point, the interim cast becomes the definitive cast (Fig. 7). Definitive restorations can now be fabricated on this cast (Fig. 8). DISCUSSION Although a rigid matrix may also be used with this technique, the 4 mm thick mouthguard material was chosen because it provides accurate results and is easier to use. The matrix, polyvinyl siloxane impression, and interim restoration are not separated when removed from the mouth. This avoids 2 possible problems of previous direct methods. The first is error from incomplete or inaccurate reinsertion of the matrix over the interim restoration at the time of soft tissue silicone application. The second is tearing or distortion of the soft tissue registration when removing it from the mouth, especially when deep undercuts exist around the interim restoration. The flexible matrix allows potential distortion of some areas of the soft tissue registration. However, the accuracy of the critical portions immediately adjacent to the interim restoration is maintained by the rigidity of the encased interim restoration.
THE JOURNAL OF PROSTHETIC DENTISTRY
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Issue
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CONCLUSIONS Although all 3 techniques described in this article can produce clinically acceptable outcomes, the proposed one offers the advantages of being more straightforward, efficient, and accurate. Reduced time and ease are the result of eliminating the need for custom impression coping fabrication. In addition, much of the proposed technique is completed in the laboratory before the patient’s soft tissue registration appointment. With the proposed technique, implant position and timing accuracy are ensured by their verification on the interim cast before definitive soft tissue registration. The accuracy of the abutment and pontic soft tissue forms are ensured by their direct registration on this cast. REFERENCES 1. Chee WW, Donovan T. Use of provisional restorations to enhance soft-tissue contours for implant restorations. Compend Contin Educ Dent 1998;19:481-9. 2. Santosa RE. Provisional restoration options in implant dentistry. Aust Dent J 2007;52:234-42. 3. Vasconcellos DK, Maziero Volpato CA, Zani IM, Bottino MA. Impression technique for ovate pontics. J Prosthet Dent 2010;105:59-61. 4. Azer SS. A simplified technique for creating a customized gingival emergence profile for implant-supported crowns. J Prosthodont 2010;19:497-501. 5. Ruggeri A, Franchi M, Marini N, Trisi P, Piatelli A. Supracrestal circular collagen fiber network around osseointegrated nonsubmerged titanium implants. Clin Oral Implants Res 1992;3:169-75. 6. Ntounis A, Petropoulou A. A technique for managing and accurate registration of periimplant soft tissues. J Prosthet Dent 2010;104:276-9. 7. Attard N, Barzilay I. A modified impression technique for accurate registration of peri-implant soft tissues. J Can Dent Assoc 2003;69:80-3. 8. Lin WS, Harris BT, Morton D. Use of implant-supported interim restorations to transfer periimplant soft tissue profiles to a milled polyurethane definitive cast. J Prosthet Dent 2013;109:333-7. 9. Man Y, Qu Y, Dam HG, Gong P. An alternative technique for the accurate transfer of periimplant soft tissue contour. J Prosthet Dent 2013;109:135-7. Corresponding author: Dr Karl E. Hegyi 18730 Northrup Lane Strongsville, OH 44149 Email: [email protected] Acknowledgments The author thanks Dr Michael Morgan for his precise implant placement; Michael Nichols, CDT, and Zsolt Tromler, CDT, of Ceramic Design Technologies for their tremendous laboratory support; and Dr Peter Dawson for his guidance and direction. Copyright © 2015 by the Editorial Council for The Journal of Prosthetic Dentistry.
Hegyi
Direct method of registering periimplant soft tissue forms for implant-supported fixed dental prostheses Karl E. Hegyi, DDS The form and health of periABSTRACT implant and pontic site tissues This article describes a direct technique for communicating implant abutment and pontic intaglio are critical for the esthetic surface forms with the dental laboratory. The technique uses a matrix and a screw-retained custom success of implant-supported interim restoration. The matrix is used to transfer the interim restoration and periimplant tissue restorations. Key factors affforms from the patient’s mouth to an implant position-verified cast. After being connected to this ecting these qualities are the cast, a silicone soft tissue replicating material is injected into the matrix. The result is a definitive cast with accurate implant position and soft tissue forms. (J Prosthet Dent 2015;-:---) abutment emergence (the subgingival portion of the restorestoration abutment and the definitive cast is poured. ration between the implant platform and gingival Concerns with this technique include the accuracy of the margin) and pontic intaglio surface forms.1-4 For the most predictable outcome, these forms should be developed implant position in the cast (dependent upon temporary with a custom interim restoration before definitive cylinder to implant analog fit) and the need to immediately pour the definitive cast after making the impression restoration.1-4 Once perfected in the interim restoration, (in order to return the interim restoration to the patient).7 they must be accurately communicated with the laboraThe second technique uses an in situ registration of tory. The purpose of this article is to describe a the interim restoration and surrounding tissues. The straightforward yet accurate method for doing this. registration and interim restoration are separately Because of the circumferential arrangement of removed from the mouth and then transferred to a collagen fibers in supracrestal periimplant tissues, their form rapidly changes when an interim restoration is previously made cast of the integrated implants. Comremoved to make an impression.5 In addition, the pontic bined with a silicone gingival material, the cast is modified to replicate soft tissue detail and becomes the site tissue form may change.3 Therefore, simply removing definitive cast.8,9 the interim restoration and using a standard fixture level The described technique is similar to this second implant impression technique is not acceptable. direct type. However, it differs from the above referenced Direct and indirect methods have been used to methods in 2 important ways: the method and materials overcome this problem. Indirect techniques involve of in situ soft tissue registration, and the method of fabricating custom impression copings to maintain the soft tissue forms developed with the interim restoration transferring this registration for definitive cast fabrication. during the impression.6 Concerns with this technique The advantages of these differences are improved accuracy and increased detail of the periimplant tissue repliinclude the time and cost required to fabricate these cation on the definitive cast. custom copings. Before implementing the technique, 2 conventional Direct techniques use the refined interim restoration dental procedures are required. The first is a fixture level to record periimplant tissue forms. These techniques fall impression made any time after implant primary stability. into 3 major types. The first uses the interim restoration The second is a screw-retained custom interim restoraas the impression coping.1,7 After making the impression, tion. In the treatment illustrated in this article, this an implant laboratory analog is attached to the interim Private practice, Strongsville, Ohio.
THE JOURNAL OF PROSTHETIC DENTISTRY
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Figure 1. Interim cast used to fabricate interim restoration and verify implant analog positions.
Figure 2. Interim cast with silicone soft tissue replicating material removed, exposing verified implant analogs and silicone injection ports.
Figure 3. Silicone injection port access openings.
Figure 4. Matrix with screw access channel dowel pins in place.
involved a custom, open tray impression (Triad TruTray Custom Tray Material; Dentsply Intl, 3.5 and 4.0 mm Open Tray Impression Copings; Thommen Medical, Panasil Initial Contact Light; Kettenbach) and a 1-piece splinted screw-retained interim restoration (3.5 and 4.0 mm Temporary Abutments; Thommen Medical, PMMA Acrylic; Huge Dental Material Co Ltd). The interim restoration was fabricated indirectly on a cast (CAD Rock; Nobilium Co, GI-MASK; Coltène/Whaledent) made from this open tray impression. The interim restoration was seated and abutment customization began 4 weeks after implant placement. In addition to these procedures, the proposed technique requires that the cast be verified to represent the definitive position and timing of the dental implants (the splinted interim restoration may be used for this purpose); accurately represent the form of all remaining teeth and restorations in that arch; and have a removable silicone soft tissue replicating material (GI-MASK; Coltène/Whaledent) represent the periimplant and pontic site soft tissue forms (Fig. 1). If these 3 requirements are met, the only difference between this cast and that required to fabricate the definitive restoration involves periimplant and pontic site soft tissue forms. Therefore, once such a cast is made (hereafter referred to as the
interim cast), it need only be modified to represent these definitive soft tissue forms for it to serve as the definitive cast. The proposed technique involves this process of modification. Although the technique is illustrated in a treatment involving 3 partial fixed dental prostheses, it may also be applied to single or multiple individual implant restorations.
THE JOURNAL OF PROSTHETIC DENTISTRY
TECHNIQUE Once implant integration is complete and the interim restoration and soft tissue forms are determined, make an accurate irreversible hydrocolloid impression (Jeltrate; Dentsply Caulk) and cast (Coe Cal; GC America) (Abrahamsen TC, “Accurate diagnostic casts from the sophisticated alginate impression-through the eyes of the master,” DVD, American Academy of Restorative Dentistry, 1999) of the involved arch. The location of the interim restoration screw access channels should be visible on this cast. 1. Fabricate a clear flexible matrix (Thermo-Forming Material Clear-Mouthguard 15000 ; Henry Schein Inc) over this cast. Remove the silicone soft tissue replicating material from the interim cast (Fig. 2). Hegyi
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2015
3
Figure 5. Matrix with encased interim implant restoration (and interim first molar crown) in polyvinyl siloxane soft tissue impression.
Figure 6. Matrix connected to interim cast after silicone injection.
Figure 7. Former interim cast after new silicone injection. This is now definitive cast.
Figure 8. Definitive restorations immediately after seating.
Trim the vestibular extension of the matrix to that of the removed silicone. If necessary, relieve soft tissue areas of the interim cast or trim the matrix so that the matrix can be completely seated without interference. Referencing the cast from step 1, drill holes through the matrix (H-219s Port Bur; Brassler USA) to allow access to the screw access channels. 2. Drill an injection port (H-219s Port Bur; Brassler USA) mesial and distal to each implant on the interim cast. These ports should communicate between a portion of the cast not covered by the matrix and the area previously occupied by the silicone soft tissue replicating material (Figs. 2, 3). 3. At the soft tissue registration appointment, clean the interim restoration screw-access channels to allow the screwdriver to engage the abutment screws. Place the matrix in the mouth and verify that the screwdriver can still engage the abutment screws through the matrix. If necessary, enlarge the holes in the matrix. 4. Remove the matrix and place appropriate diameter dowel pins (Project 70 Stainless Type 303; Carpenter Technology Corp) to obturate the abutment screw-access channels (1.5 mm for Thommen 3.5 Hegyi
mm and 1.8 mm for Thommen 4.0 provisional abutments). The dowel pins should be long enough to extend approximately 4 to 5 mm beyond the access channel openings. Confirm that with the dowel pins in place the matrix can still be fully seated over the interim restoration without interference (Fig. 4). (If interarch space permits, laboratory fabrication screws may be used in place of the abutment screws and dowel pins in this and subsequent steps.) 5. With dowel pins in the access channels, inject impression material (Coe Syringe; GC America Inc, Panasil Initial Contact Light; Kettenbach) around the soft tissue surrounding the interim restoration, and seat the matrix. It is important that the matrix, impression material, and interim restoration not separate during the following step. If necessary, a small amount of adhesive (Universal VPS Adhesive; GC America) may be applied to the interim restoration and matrix. Once the impression material is set, remove the dowel pins, loosen the abutment screws, and remove the matrix (along with the encased interim restoration and soft tissue impression) (Fig. 5). THE JOURNAL OF PROSTHETIC DENTISTRY
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6. Spray the tissue side of the matrix with a release agent (Lang Silicone Spray; Lang Dental Mfg Co) and connect the matrix (containing the encased interim restoration and soft tissue impression) to the interim cast. Tighten the abutment screws of the interim restoration enough to ensure that the interim restoration is completely seated into the implant analogs. 7. Sequentially inject silicone soft tissue replicating material (GI-MASK; Coltène/Whaledent) into each port until excess material extrudes through the next port (Fig. 6). 8. Upon setting of the silicone soft tissue replicating material, loosen the interim abutment screws and remove the matrix. An accurate registration of the interim abutments, periimplant, and pontic site tissue forms are now represented on the interim cast. At this point, the interim cast becomes the definitive cast (Fig. 7). Definitive restorations can now be fabricated on this cast (Fig. 8). DISCUSSION Although a rigid matrix may also be used with this technique, the 4 mm thick mouthguard material was chosen because it provides accurate results and is easier to use. The matrix, polyvinyl siloxane impression, and interim restoration are not separated when removed from the mouth. This avoids 2 possible problems of previous direct methods. The first is error from incomplete or inaccurate reinsertion of the matrix over the interim restoration at the time of soft tissue silicone application. The second is tearing or distortion of the soft tissue registration when removing it from the mouth, especially when deep undercuts exist around the interim restoration. The flexible matrix allows potential distortion of some areas of the soft tissue registration. However, the accuracy of the critical portions immediately adjacent to the interim restoration is maintained by the rigidity of the encased interim restoration.
THE JOURNAL OF PROSTHETIC DENTISTRY
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Issue
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CONCLUSIONS Although all 3 techniques described in this article can produce clinically acceptable outcomes, the proposed one offers the advantages of being more straightforward, efficient, and accurate. Reduced time and ease are the result of eliminating the need for custom impression coping fabrication. In addition, much of the proposed technique is completed in the laboratory before the patient’s soft tissue registration appointment. With the proposed technique, implant position and timing accuracy are ensured by their verification on the interim cast before definitive soft tissue registration. The accuracy of the abutment and pontic soft tissue forms are ensured by their direct registration on this cast. REFERENCES 1. Chee WW, Donovan T. Use of provisional restorations to enhance soft-tissue contours for implant restorations. Compend Contin Educ Dent 1998;19:481-9. 2. Santosa RE. Provisional restoration options in implant dentistry. Aust Dent J 2007;52:234-42. 3. Vasconcellos DK, Maziero Volpato CA, Zani IM, Bottino MA. Impression technique for ovate pontics. J Prosthet Dent 2010;105:59-61. 4. Azer SS. A simplified technique for creating a customized gingival emergence profile for implant-supported crowns. J Prosthodont 2010;19:497-501. 5. Ruggeri A, Franchi M, Marini N, Trisi P, Piatelli A. Supracrestal circular collagen fiber network around osseointegrated nonsubmerged titanium implants. Clin Oral Implants Res 1992;3:169-75. 6. Ntounis A, Petropoulou A. A technique for managing and accurate registration of periimplant soft tissues. J Prosthet Dent 2010;104:276-9. 7. Attard N, Barzilay I. A modified impression technique for accurate registration of peri-implant soft tissues. J Can Dent Assoc 2003;69:80-3. 8. Lin WS, Harris BT, Morton D. Use of implant-supported interim restorations to transfer periimplant soft tissue profiles to a milled polyurethane definitive cast. J Prosthet Dent 2013;109:333-7. 9. Man Y, Qu Y, Dam HG, Gong P. An alternative technique for the accurate transfer of periimplant soft tissue contour. J Prosthet Dent 2013;109:135-7. Corresponding author: Dr Karl E. Hegyi 18730 Northrup Lane Strongsville, OH 44149 Email: [email protected] Acknowledgments The author thanks Dr Michael Morgan for his precise implant placement; Michael Nichols, CDT, and Zsolt Tromler, CDT, of Ceramic Design Technologies for their tremendous laboratory support; and Dr Peter Dawson for his guidance and direction. Copyright © 2015 by the Editorial Council for The Journal of Prosthetic Dentistry.
Hegyi