A technique for fabricating single screw-retained implant-supported interim crowns in conjunction with implant surgery M. Eric McRory, DDSa and David R. Cagna, DMD, MSb University of Tennessee Health Science Center College of Dentistry, Memphis, Tenn This article presents an intraoral technique for fabricating single screw-retained implant-supported interim crowns immediately after surgical implant placement in extraction sites. The technique may be used with any implant system that provides a provisional abutment or an open-tray impression coping that can be modified for use as a provisional abutment. (J Prosthet Dent 2014;111:455-459) One approach to the replacement of a single missing tooth involves surgical implant placement followed by the fixation of a transmucosal healing abutment and appropriate soft tissue closure.1 Several months later, upon osseous integration and soft tissue maturation, the restoring dentist can initiate procedures to fabricate a definitive restoration, designing emergence contours to properly support adjacent soft tissues. This traditional approach presents a specific challenge for both the restorative dentist and the laboratory technician, because when the periimplant soft tissues heal around a stock healing abutment after surgical implant placement, a cylindrical transmucosal passageway is created rather than the more natural emergence profile required to facilitate optimal restorative esthetics.2,3 Achieving a biologically and esthetically appropriate soft tissue emergence all too frequently relies on the dental technician’s best estimation in the laboratory. If the technician contours the emergence profile excessively, healthy periimplant tissue may prevent complete restoration placement, and the soft tissue may need to be recontoured surgically. If the technician
undercontours the coronal emergence, or incorrectly estimates the optimal gingival architecture, the definitive restoration may have poor esthetics. For these reasons, fabricating an optimally contoured interim crown at the time of implant placement should be considered.4-9 This article describes a clinical technique that permits periimplant soft tissues to heal against an optimally developed interim crown surface. This technique facilitates desirable and predictable soft tissue maturation, eliminating problems associated with the more traditional approach.
TECHNIQUE 1. Complete a diagnostic examination, paying particular attention to bone quality and volume at the intended implant site. Make a periapical radiograph of the surgical site by placing a 5.0-mm metal calibration ball (RadioMark; Salvin Dental Specialties Inc) in the image. Alternately, obtain a cone beam computed tomography image. Verify that adequate bone is available for the planned implant procedure. 2. Obtain preoperative mounted diagnostic casts. If the anatomic
form of the tooth to be extracted requires modification, perform appropriate waxing procedures. Evaluate the occlusion with an articulator. Reduce the functional contacts of the planned implant restoration in maximum intercuspation and all eccentric positions. Duplicate the cast in dental stone (Vel-Mix Die Stone; Kerr Corp). 3. Fabricate an interim restoration matrix and a surgical template. For each, pressure-form a 1.5-mm thermal plastic sheet (Copyplast; Scheu-Dental) over the cast. Trim the interim restoration matrix to include 1 or 2 teeth on either side of the planned restoration, extending approximately 2.0 mm beyond the free gingival margins. Trim the surgical template in the same manner, but include an opening through the lingual surface of the planned restoration that is large enough to accommodate the implant surgical drills (Fig. 1). Disinfect the matrix and template in 0.12% chlorhexidine gluconate (Peridex; 3M ESPE/Omni Healthcare). 4. Initiate the surgical phase by extracting the tooth atraumatically with a standard surgical protocol. Care must be taken to preserve the delicate facial plate of bone and to avoid trauma to the interproximal gingival tissue.
Presented at the American Academy of Restorative Dentistry 81st Annual Meeting, Chicago, Ill, February 2011. a
Private practice, Bellingham, Wash. Associate Dean of Postgraduate Affairs, Director of Advanced Prosthodontics Program, Department of Prosthodontics, University of Tennessee Health Science Center College of Dentistry, Memphis, Tenn.
b
McRory and Cagna
456
Volume 111 Issue 6
1 Duplicate cast of diagnostic waxing. Surgical template in place trimmed to accommodate surgical drills. Red dot indicates desired screw-access location in interim crown.
2 Space between buccal alveolus and implant is filled with bone graft material covered with resorbable cellulose sponge material.
3 Extraoral adjustment of provisional abutment to accommodate planned interim crown contours. Debride the extraction socket and promote bleeding of the alveolar bone. 5. Place the surgical template. After the implant system’s recommended
osteotomy sequence, create a pilot hole with a sharp-pointed pilot drill (Power Point Surgical Drill; Salvin Dental Specialties Inc). Use the template to guide
The Journal of Prosthetic Dentistry
the osteotomy trajectory. Placing the long axis of the implant lingual to the planned incisal edge will permit an ideal retention screw access opening to optimize the esthetics of both the interim and definitive restorations. 6. Further enlarge the osteotomy by using the system-specific surgical protocol with the target vertical position implant being 3 to 4 mm apical to the anticipated cementoenamel junction of the restoration. Use surgical template contours and adjacent cementoenamel junctions as landmarks. Place the implant into the prepared site. Use a hand-driven torque wrench to place the implant to its final depth to prevent stripping of the delicate bony threads. If a minimum of 35 Ncm of force is not achieved at the final implant insertion, the placement of a fixed interim crown should be abandoned.10,11 An alternate interim restorative approach should be used that minimizes implant loading. 7. Evaluate the space remaining between the implant and the walls of the extraction socket. If a gap of 2 mm or more exists, particulate bone grafting material (Bio-Oss; Osteohealth) may be used to support osseous healing.12-15 Coverage with a narrow strip of resorbable cellulose sponge material (Gelfoam; Pfizer) may also be considered (Fig. 2). Allow smaller gaps to fill naturally. 8. Initiate the interim restoration fabrication by attaching a provisional abutment (Temporary AbutmentEngaging, Titanium; Nobel Biocare USA) onto the implant. With a sterile pen (Tissue-Mark Surgical Pen; Salvin Dental Specialties Inc), mark the abutment 1.5 to 2.0 mm apical to the anticipated incisal edge of the crown using adjacent teeth as landmarks. Place a second mark to identify the lingual surface. 9. Remove the provisional abutment. With a high-speed bur (H31.31.010; Brasseler USA) and water irrigation, section the abutment to the levels dictated by the planned restoration (Fig. 3). DO NOT adjust the abutment while it is attached to the implant. Replace the abutment and
McRory and Cagna
June 2014
457
4 Thin veneer of conventional light-polymerized composite resin placed on facial surface of interim crown matrix.
5 Screw access channel covered by thin layer of composite resin (indicated by dark halo in cingulum area) that is easily removed.
6 Interim crown before trimming, shaping, and polishing. trial-fit the matrix. Continue to remove and adjust the abutment contours until the matrix seats completely with 0.5 to 1.0 mm of clearance between the matrix and abutment.
McRory and Cagna
10. Remove the abutment, clean it, and dry it thoroughly. Apply a thin layer of opaque composite resin (Kerr Kolor þ Plus Kit; Kerr Corp) to mask all external metal surfaces. Replace the
abutment and fill the screw access channel with cotton pellets. 11. Create the facial veneer of the planned interim crown. With a plastic instrument, apply a 0.5- to 1.0-mm layer of composite resin (Filtek Supreme Ultra; 3M ESPE) into the interim matrix covering only the facial and incisal surfaces of the planned interim restoration (Fig. 4). Extend the composite resin material slightly past the proximal-facial line angles. Do not extend it onto the lingual surface. Place the matrix. Light-polymerize the composite resin through the matrix. 12. Carefully remove the matrix, ensuring that the polymerized facial veneer remains in the matrix. Fill the space remaining in the matrix to complete the contours of the interim restoration with chemically activated composite resin (Luxatemp; DMG America). Quickly clean and dry the opaqued abutment and replace the matrix. After complete resin polymerization, remove the matrix. Identify the location of the screw access channel (dark shadowing at the cingulum). With a high-speed bur, cut through the thin layer of resin covering the screw access channel (Fig. 5). 13. Retrieve the cotton from the screw access channel, remove the retaining screw, and recover the interim restoration (Fig. 6). A flame-shaped finishing bur (H246.31.009 7901 FG Flame; Brasseler USA) may be required to free the restoration from adjacent undercuts. With an acrylic bur (UC079EF-060; Axis Dental), adjust the general shape of the restoration. Complete or correct the subgingival contours with light-activated composite resin (Filtek Supreme Ultra; 3M ESPE) to blend the cervical emergence profile harmoniously from the metal collar of the abutment to the coronal contours created by the matrix (Fig. 7). Finish the restoration and polish with a waterslurry of fine pumice followed by acrylic resin polishing compound (Universal Polishing Paste; Ivoclar Vivadent) on a rag wheel in a dental lathe. Disinfect the interim crown in chlorhexidine gluconate 0.12% oral rinse (Peridex; 3M ESPE/Omni Healthcare).
458
Volume 111 Issue 6
7 Completed interim crown with proper emergence profile and finely polished surface.
8 Periapical radiograph indicating complete seating of interim crown.
14. Place the interim crown and hand-tighten the retention screw. Make a periapical radiograph to ensure complete seating (Fig. 8). Evaluate the proximal contacts with floss and relieve tight contacts with a rubber wheel (Burlew Wheel; J.F. Jelenko and Co). Use disclosing paste (Pressure Indicator Paste; Mizzy Inc) to identify and relieve subgingival interferences with a rubber wheel (Burlew Wheel; J.F. Jelenko and Co). Temporary blanching (10 to 15 minutes) of the gingival tissue adjacent to the newly seated interim crown is expected as the tissue slowly adapts to the restoration contours. Condense presterilized plumber’s polytetrafluoroethylene tape (A1441 PTFE Seal Tape; AmPro)16 over the abutment screw and fill the screw access channel with provisional filling material (Cavit; 3M ESPE). 15. To facilitate implant stability during osseointegration, carefully manage the interim restoration occlusion. Eliminate all maximum intercuspation contacts and eliminate or reduce eccentric contacts, if possible. Instruct the patient to avoid masticatory loading of the interim restoration during the integration period. 16. Recall the patient 1 week after surgery (Fig. 9). Remove the interim restoration and evaluate the health of the periimplant soft tissue. Replace the interim restoration and retighten the retaining screw to the manufacturer’s recommended force. Condense presterilized plumber’s tape over the abutment screw and fill the screw access channel with a composite resin (Filtek Supreme Ultra; 3M ESPE). Reinforce oral care and mastication instructions. Schedule future recall appointments.
SUMMARY
9 Interim crown 1 week after surgical implant placement.
The Journal of Prosthetic Dentistry
This technique illustrates a method for fabricating a single implantsupported interim crown in conjunction with surgical implant placement in an extraction site. Providing an interim crown in the manner described helps preserve and support the delicate
McRory and Cagna
June 2014 periimplant soft tissues and helps avoid many of the complications associated with a removable single-tooth interim prosthesis. A fixed interim crown helps promote biologically and esthetically appropriate soft tissue emergence for the definitive prosthesis. However, this technique is not appropriate for every patient; specific criteria for implant placement and implant stability are imperative for success with this technique.
REFERENCES 1. Misch CE. Anterior single-tooth replacement: surgical consideration. In: Contemporary implant dentistry. 3rd ed. St Louis: Mosby; 2008. p. 739-68. 2. Papazian S, Morgano SM. A laboratory procedure to facilitate development of an emergence profile with a custom implant abutment. J Prosthet Dent 1998; 79:232-4. 3. Shor A, Schuler R, Goto Y. Indirect implantsupported fixed provisional restoration in the esthetic zone: fabrication technique and treatment workflow. J Esthet Restor Dent 2008;20:82-95. 4. Spear FM, Mathews DM, Kokich VG. Interdisciplinary management of single-tooth implants. Semin Orthod 1997;3:45-72.
McRory and Cagna
459 5. Chee WW, Donovan T. Use of provisional restorations to enhance soft-tissue contours for implant restorations. Compend Contin Educ Dent 1998;19:481-9. 6. Mathews DP. Soft tissue management around implants in the esthetic zone. Int J Periodont Rest Dent 2000;20:141-9. 7. Kan JYK, Rungcharassaeng K, Lozada J. Immediate placement and provisionalization of maxillary anterior single implants: 1-year prospective study. Int J Oral Maxillofac Implants 2003;18:31-9. 8. DeRouck T, Collys K, Wyn I, Cosyn J. Instant provisionalization of immediate single-tooth implants is essential to optimize esthetic treatment outcome. Clin Oral Implants Res 2009;20:566-70. 9. Su H, Gonzales-Martin O, Weisgold A, Lee E. Considerations of implant abutment and crown contour: critical contour and subcritical contour. Int J Periodontics Restorative Dent 2010;30:335-43. 10. Ottoni JMP, Oliveira ZFL, Mansini R, Cabral AM. Correlation between placement torque and survival of single-tooth implants. Int J Oral Maxillofac Implants 2005;20:769-76. 11. Wang H-L, Orimaner Z, Palti A, Perel ML, Trisi P, Sammartino G. Consensus conference on immediate loading: the single tooth and partial edentulous areas. Implant Dent 2006;15:324-33. 12. Covani U, Cornelini R, Barone A. Buccolingual bone remodeling around implants placed into immediate extraction sockets: a case series. J Periodontol 2003; 74:268-73.
13. Botticelli D, Berglundh T, Lindhe J. Hardtissue alterations following immediate implant placement in extraction sites. J Clin Periodontol 2004;31:820-8. 14. Chen ST, Darby IB, Adams GG, Reynolds EC. A prospective clinical study of bone augmentation techniques at immediate implants. Clin Oral Implants Res 2005;16: 176-84. 15. Chen ST, Darby IB, Reynolds EC. A prospective clinical study of non-submerged immediate implants: clinical outcomes and esthetic results. Clin Oral Implants Res 2007;18:552-62. 16. Moráguez OD, Belser UC. The use of polytetrafluoroethylene tape for the management of screw access channels in implant-supported prostheses. J Prosthet Dent 2010;103: 189-91. Corresponding author: Dr David R. Cagna University of Tennessee Health Science Center College of Dentistry Department of Prosthodontics 875 Union Ave Memphis, TN 38163 E-mail: [email protected] Copyright ª 2014 by the Editorial Council for The Journal of Prosthetic Dentistry.
undercontours the coronal emergence, or incorrectly estimates the optimal gingival architecture, the definitive restoration may have poor esthetics. For these reasons, fabricating an optimally contoured interim crown at the time of implant placement should be considered.4-9 This article describes a clinical technique that permits periimplant soft tissues to heal against an optimally developed interim crown surface. This technique facilitates desirable and predictable soft tissue maturation, eliminating problems associated with the more traditional approach.
TECHNIQUE 1. Complete a diagnostic examination, paying particular attention to bone quality and volume at the intended implant site. Make a periapical radiograph of the surgical site by placing a 5.0-mm metal calibration ball (RadioMark; Salvin Dental Specialties Inc) in the image. Alternately, obtain a cone beam computed tomography image. Verify that adequate bone is available for the planned implant procedure. 2. Obtain preoperative mounted diagnostic casts. If the anatomic
form of the tooth to be extracted requires modification, perform appropriate waxing procedures. Evaluate the occlusion with an articulator. Reduce the functional contacts of the planned implant restoration in maximum intercuspation and all eccentric positions. Duplicate the cast in dental stone (Vel-Mix Die Stone; Kerr Corp). 3. Fabricate an interim restoration matrix and a surgical template. For each, pressure-form a 1.5-mm thermal plastic sheet (Copyplast; Scheu-Dental) over the cast. Trim the interim restoration matrix to include 1 or 2 teeth on either side of the planned restoration, extending approximately 2.0 mm beyond the free gingival margins. Trim the surgical template in the same manner, but include an opening through the lingual surface of the planned restoration that is large enough to accommodate the implant surgical drills (Fig. 1). Disinfect the matrix and template in 0.12% chlorhexidine gluconate (Peridex; 3M ESPE/Omni Healthcare). 4. Initiate the surgical phase by extracting the tooth atraumatically with a standard surgical protocol. Care must be taken to preserve the delicate facial plate of bone and to avoid trauma to the interproximal gingival tissue.
Presented at the American Academy of Restorative Dentistry 81st Annual Meeting, Chicago, Ill, February 2011. a
Private practice, Bellingham, Wash. Associate Dean of Postgraduate Affairs, Director of Advanced Prosthodontics Program, Department of Prosthodontics, University of Tennessee Health Science Center College of Dentistry, Memphis, Tenn.
b
McRory and Cagna
456
Volume 111 Issue 6
1 Duplicate cast of diagnostic waxing. Surgical template in place trimmed to accommodate surgical drills. Red dot indicates desired screw-access location in interim crown.
2 Space between buccal alveolus and implant is filled with bone graft material covered with resorbable cellulose sponge material.
3 Extraoral adjustment of provisional abutment to accommodate planned interim crown contours. Debride the extraction socket and promote bleeding of the alveolar bone. 5. Place the surgical template. After the implant system’s recommended
osteotomy sequence, create a pilot hole with a sharp-pointed pilot drill (Power Point Surgical Drill; Salvin Dental Specialties Inc). Use the template to guide
The Journal of Prosthetic Dentistry
the osteotomy trajectory. Placing the long axis of the implant lingual to the planned incisal edge will permit an ideal retention screw access opening to optimize the esthetics of both the interim and definitive restorations. 6. Further enlarge the osteotomy by using the system-specific surgical protocol with the target vertical position implant being 3 to 4 mm apical to the anticipated cementoenamel junction of the restoration. Use surgical template contours and adjacent cementoenamel junctions as landmarks. Place the implant into the prepared site. Use a hand-driven torque wrench to place the implant to its final depth to prevent stripping of the delicate bony threads. If a minimum of 35 Ncm of force is not achieved at the final implant insertion, the placement of a fixed interim crown should be abandoned.10,11 An alternate interim restorative approach should be used that minimizes implant loading. 7. Evaluate the space remaining between the implant and the walls of the extraction socket. If a gap of 2 mm or more exists, particulate bone grafting material (Bio-Oss; Osteohealth) may be used to support osseous healing.12-15 Coverage with a narrow strip of resorbable cellulose sponge material (Gelfoam; Pfizer) may also be considered (Fig. 2). Allow smaller gaps to fill naturally. 8. Initiate the interim restoration fabrication by attaching a provisional abutment (Temporary AbutmentEngaging, Titanium; Nobel Biocare USA) onto the implant. With a sterile pen (Tissue-Mark Surgical Pen; Salvin Dental Specialties Inc), mark the abutment 1.5 to 2.0 mm apical to the anticipated incisal edge of the crown using adjacent teeth as landmarks. Place a second mark to identify the lingual surface. 9. Remove the provisional abutment. With a high-speed bur (H31.31.010; Brasseler USA) and water irrigation, section the abutment to the levels dictated by the planned restoration (Fig. 3). DO NOT adjust the abutment while it is attached to the implant. Replace the abutment and
McRory and Cagna
June 2014
457
4 Thin veneer of conventional light-polymerized composite resin placed on facial surface of interim crown matrix.
5 Screw access channel covered by thin layer of composite resin (indicated by dark halo in cingulum area) that is easily removed.
6 Interim crown before trimming, shaping, and polishing. trial-fit the matrix. Continue to remove and adjust the abutment contours until the matrix seats completely with 0.5 to 1.0 mm of clearance between the matrix and abutment.
McRory and Cagna
10. Remove the abutment, clean it, and dry it thoroughly. Apply a thin layer of opaque composite resin (Kerr Kolor þ Plus Kit; Kerr Corp) to mask all external metal surfaces. Replace the
abutment and fill the screw access channel with cotton pellets. 11. Create the facial veneer of the planned interim crown. With a plastic instrument, apply a 0.5- to 1.0-mm layer of composite resin (Filtek Supreme Ultra; 3M ESPE) into the interim matrix covering only the facial and incisal surfaces of the planned interim restoration (Fig. 4). Extend the composite resin material slightly past the proximal-facial line angles. Do not extend it onto the lingual surface. Place the matrix. Light-polymerize the composite resin through the matrix. 12. Carefully remove the matrix, ensuring that the polymerized facial veneer remains in the matrix. Fill the space remaining in the matrix to complete the contours of the interim restoration with chemically activated composite resin (Luxatemp; DMG America). Quickly clean and dry the opaqued abutment and replace the matrix. After complete resin polymerization, remove the matrix. Identify the location of the screw access channel (dark shadowing at the cingulum). With a high-speed bur, cut through the thin layer of resin covering the screw access channel (Fig. 5). 13. Retrieve the cotton from the screw access channel, remove the retaining screw, and recover the interim restoration (Fig. 6). A flame-shaped finishing bur (H246.31.009 7901 FG Flame; Brasseler USA) may be required to free the restoration from adjacent undercuts. With an acrylic bur (UC079EF-060; Axis Dental), adjust the general shape of the restoration. Complete or correct the subgingival contours with light-activated composite resin (Filtek Supreme Ultra; 3M ESPE) to blend the cervical emergence profile harmoniously from the metal collar of the abutment to the coronal contours created by the matrix (Fig. 7). Finish the restoration and polish with a waterslurry of fine pumice followed by acrylic resin polishing compound (Universal Polishing Paste; Ivoclar Vivadent) on a rag wheel in a dental lathe. Disinfect the interim crown in chlorhexidine gluconate 0.12% oral rinse (Peridex; 3M ESPE/Omni Healthcare).
458
Volume 111 Issue 6
7 Completed interim crown with proper emergence profile and finely polished surface.
8 Periapical radiograph indicating complete seating of interim crown.
14. Place the interim crown and hand-tighten the retention screw. Make a periapical radiograph to ensure complete seating (Fig. 8). Evaluate the proximal contacts with floss and relieve tight contacts with a rubber wheel (Burlew Wheel; J.F. Jelenko and Co). Use disclosing paste (Pressure Indicator Paste; Mizzy Inc) to identify and relieve subgingival interferences with a rubber wheel (Burlew Wheel; J.F. Jelenko and Co). Temporary blanching (10 to 15 minutes) of the gingival tissue adjacent to the newly seated interim crown is expected as the tissue slowly adapts to the restoration contours. Condense presterilized plumber’s polytetrafluoroethylene tape (A1441 PTFE Seal Tape; AmPro)16 over the abutment screw and fill the screw access channel with provisional filling material (Cavit; 3M ESPE). 15. To facilitate implant stability during osseointegration, carefully manage the interim restoration occlusion. Eliminate all maximum intercuspation contacts and eliminate or reduce eccentric contacts, if possible. Instruct the patient to avoid masticatory loading of the interim restoration during the integration period. 16. Recall the patient 1 week after surgery (Fig. 9). Remove the interim restoration and evaluate the health of the periimplant soft tissue. Replace the interim restoration and retighten the retaining screw to the manufacturer’s recommended force. Condense presterilized plumber’s tape over the abutment screw and fill the screw access channel with a composite resin (Filtek Supreme Ultra; 3M ESPE). Reinforce oral care and mastication instructions. Schedule future recall appointments.
SUMMARY
9 Interim crown 1 week after surgical implant placement.
The Journal of Prosthetic Dentistry
This technique illustrates a method for fabricating a single implantsupported interim crown in conjunction with surgical implant placement in an extraction site. Providing an interim crown in the manner described helps preserve and support the delicate
McRory and Cagna
June 2014 periimplant soft tissues and helps avoid many of the complications associated with a removable single-tooth interim prosthesis. A fixed interim crown helps promote biologically and esthetically appropriate soft tissue emergence for the definitive prosthesis. However, this technique is not appropriate for every patient; specific criteria for implant placement and implant stability are imperative for success with this technique.
REFERENCES 1. Misch CE. Anterior single-tooth replacement: surgical consideration. In: Contemporary implant dentistry. 3rd ed. St Louis: Mosby; 2008. p. 739-68. 2. Papazian S, Morgano SM. A laboratory procedure to facilitate development of an emergence profile with a custom implant abutment. J Prosthet Dent 1998; 79:232-4. 3. Shor A, Schuler R, Goto Y. Indirect implantsupported fixed provisional restoration in the esthetic zone: fabrication technique and treatment workflow. J Esthet Restor Dent 2008;20:82-95. 4. Spear FM, Mathews DM, Kokich VG. Interdisciplinary management of single-tooth implants. Semin Orthod 1997;3:45-72.
McRory and Cagna
459 5. Chee WW, Donovan T. Use of provisional restorations to enhance soft-tissue contours for implant restorations. Compend Contin Educ Dent 1998;19:481-9. 6. Mathews DP. Soft tissue management around implants in the esthetic zone. Int J Periodont Rest Dent 2000;20:141-9. 7. Kan JYK, Rungcharassaeng K, Lozada J. Immediate placement and provisionalization of maxillary anterior single implants: 1-year prospective study. Int J Oral Maxillofac Implants 2003;18:31-9. 8. DeRouck T, Collys K, Wyn I, Cosyn J. Instant provisionalization of immediate single-tooth implants is essential to optimize esthetic treatment outcome. Clin Oral Implants Res 2009;20:566-70. 9. Su H, Gonzales-Martin O, Weisgold A, Lee E. Considerations of implant abutment and crown contour: critical contour and subcritical contour. Int J Periodontics Restorative Dent 2010;30:335-43. 10. Ottoni JMP, Oliveira ZFL, Mansini R, Cabral AM. Correlation between placement torque and survival of single-tooth implants. Int J Oral Maxillofac Implants 2005;20:769-76. 11. Wang H-L, Orimaner Z, Palti A, Perel ML, Trisi P, Sammartino G. Consensus conference on immediate loading: the single tooth and partial edentulous areas. Implant Dent 2006;15:324-33. 12. Covani U, Cornelini R, Barone A. Buccolingual bone remodeling around implants placed into immediate extraction sockets: a case series. J Periodontol 2003; 74:268-73.
13. Botticelli D, Berglundh T, Lindhe J. Hardtissue alterations following immediate implant placement in extraction sites. J Clin Periodontol 2004;31:820-8. 14. Chen ST, Darby IB, Adams GG, Reynolds EC. A prospective clinical study of bone augmentation techniques at immediate implants. Clin Oral Implants Res 2005;16: 176-84. 15. Chen ST, Darby IB, Reynolds EC. A prospective clinical study of non-submerged immediate implants: clinical outcomes and esthetic results. Clin Oral Implants Res 2007;18:552-62. 16. Moráguez OD, Belser UC. The use of polytetrafluoroethylene tape for the management of screw access channels in implant-supported prostheses. J Prosthet Dent 2010;103: 189-91. Corresponding author: Dr David R. Cagna University of Tennessee Health Science Center College of Dentistry Department of Prosthodontics 875 Union Ave Memphis, TN 38163 E-mail: [email protected] Copyright ª 2014 by the Editorial Council for The Journal of Prosthetic Dentistry.
