Immediate Implant Placement, Immediate Load With Same-Day Fully Digital Fabrication of a Screw-Retained Provisional Implant Prosthesis
David A. Gelb, DDS; Michael Klein, DDS; and Michael Tuckman
This article describes the use of technology capable of converting a failed dentition to a full-arch screw-retained implant-supported provisional restoration in one day using a fully digital restorative protocol. With this expedited digital treatment, the transition to a restored dentition is completed without the need for any physical impressions. Predicated on facially driven virtual smile designs, sophisticated engineering designs, complex algorithms, artificial intelligence, and novel laboratory and clinical workflows, the protocol allows for streamlined, same-day digital delivery of an in-house 3D-printed provisional prosthesis after implant placement surgery.
Implant dentistry has predictably provided a stable foundation to support implant prostheses, restoring function and esthetics to both failing and edentulous dentitions. This success has been predicated on the well-documented research by Bränemark1-4 and numerous reports over the past several decades substantiating osseointegration as the ideal predictable basis to support tooth replacement and thereby restore esthetics and establish function.5-8
Since its inception, implant dentistry has evolved with many enhancements culminating in today's proven protocols of immediate implant surgery and immediate load.9-21 The prosthetic sequence has generally been consistent over the years. Transfer impressions have been used to capture implant location, and conventional prosthetic means have been used resulting in the fabrication of cement- or screw-retained implant-supported prostheses that satisfy the dentition esthetically, functionally, and phonetically. This is typically preceded by a healing period of 4 to 6 months for osseointegration, and then numerous prosthetic appointments are scheduled until delivery of the final prosthesis.
A Digital Process
A recently developed streamlined digital process, as demonstrated in the cases presented in this report, involves fabrication of an optimally esthetic and functional prosthesis that provides a precise and passive fit on multi-unit abutments screwed on the implants, establishing proper lip support and rejuvenating esthetic appearance. This protocol allows for same-day digital delivery of an in-house 3D-printed provisional prosthesis after implant placement surgery. In this manner the prosthetic sequence is significantly reduced, providing restoration of esthetics and function digitally in one day. The technology aims to optimize the accuracy of soft-tissue architecture and implant position capture while enabling the design and manufacture of the most ideal prosthesis for the selected dentition taking into consideration patient photographs and digital scanning of the dentition and soft tissue.
An intraoral scanner is used presurgically and at the time of surgery to scan soft tissues and existing dentition with next-generation proprietary scan gauges (Nexus iOS, nexusios.com). The scan gauges are placed on multi-unit abutments secured to the implants and scanned following a highly specific protocol to capture the exact position of the implants. From this information, using proprietary technology and protocols, an STL file of the optimal provisional prosthesis is produced, taking into consideration the many algorithms in an artificial intelligence (AI) memory bank to generate a patient-specific prosthetic file. This file is then transmitted to the local drive via a proprietary web portal and sent to the in-office 3D printer for fabrication of a screw-retained provisional implant prosthesis.
To summarize, a series of predetermined intraoral scans are taken at the time of surgery that provide geometric information incorporating hard tissue, soft tissue, and the proprietary, highly precise seven-sided scan gauges, which are screw-retained to the multi-unit abutments that are screwed onto the implants, capturing the exact position of the implants. This data serves as input for a digital impression. Computer algorithms then digitally calibrate the absolute abutment positions and ideal prosthetic design taking into account vertical dimension, correct bite relationships, and dentition. Subsequently, a 3D STL file is produced intended for in-house production of a provisional prosthesis that fits precisely on the multi-unit abutments attached to the implants.
The sequence concludes with the delivery of a screw-retained provisional implant prosthesis on the day of surgery. After integration is confirmed, the digital workflow is used to also efficiently fabricate the final restoration. This protocol provides digital delivery of an esthetic provisional screw-retained implant prosthesis on the day of implant surgery without the need for any physical impressions or prosthetic conversions.
The following case reports delineate the Nexus iOS treatment protocol and document the particular steps in this treatment sequence.
A 36-year-old male patient presented with a highly compromised maxillary dentition comprised of only teeth Nos. 4, 6, 7, 9, 10, 11, and 14 (Figure 1 and Figure 2). This poor condition was the result of only sporadic dental care with extractions and no teeth replacements. Soft tissues had normal contour, and bone profiles were generally sustained and favorable. The patient was excited about having the option to transform his compromised esthetics and function in one visit.
At the initial appointment a panoramic x-ray and periapical x-rays were taken. As part of the protocol, photographs of the patient's head to shoulders were taken, and scans of the teeth and soft tissue were captured with an intraoral scanner (TRIOS 4, 3Shape, 3shape.com). These images were then sent electronically to the implant designer and manufacturer (Osteon Medical, osteonmedical.com) via nexusios.com. Five days later, a virtual smile design (VSD) was provided for review and approval
At the following visit the patient was anesthetized with xylocaine with 1:100,000 epinephrine. Teeth Nos. 4, 6, and 11 were extracted, and immediate implants (Paltop Dynamic Conical, Keystone Dental Group, keystonedental.com) with multi-unit abutments were placed prosthetically correctly with favorable insertion torques in sites Nos. 6 and 11 (Figure 3). Scan gauges (Nexus iOS) were attached to the multi-unit abutments, and a scan was taken to capture the location of the implants with a reference to the remaining teeth with capture of the soft tissues.
Subsequently, teeth Nos. 7, 9, and 10 were carefully extracted with retention of tooth No. 14 to maintain vertical dimension of occlusion with opposing tooth No. 19. An immediate implant with a multi-unit abutment was placed in site No. 4, and additional implants with multi-unit abutments were placed in sites Nos. 8 and 13. All multi-unit abutments were torqued to 30 Ncm.
Scan gauges were then attached to the multi-unit abutments on the remaining implants so that all the implants were now in place with scan gauges (Figure 4). A scan was taken to capture all of the implants and surrounding soft tissue. The scanning protocol calls for scanning left to right, and then a separate scan right to left. These files were then sent electronically to nexusios.com.
The computer software (Osteon Medical) then calibrates based on a unique durable medical equipment (DME) file that is assigned with the scan gauge kit used for the left to right and right to left scan gauge data. The scan gauge data captured is used with proprietary AI software to establish exact multi-unit positioning. The facially driven VSD then gets incorporated with the surgical scan data provided by the surgeon. The multiplicity of algorithms is accessed until an ideal file is established that contains an optimally designed prosthesis that will precisely fit, via screw retention, on the multi-unit abutments to secure a full-arch screw-retained provisional prosthesis.
The implant company (Osteon Medical) then returned an STL design file electronically via email. The office staff sent this file to the practice's 3D printer (Pro 55S, SprintRay, sprintray.com), and the appropriate color nanoceramic resin (OnX, SprintRay) was used to print the prosthesis at 100 microns. Next, metal titanium (ti)-base cylinders, made specifically for the multi-unit abutments, were inserted into the prosthesis, which was then stained and glazed, and gingival color was applied to establish optimum esthetics (Figure 5).
The completed provisional prosthesis was then screwed onto the multi-unit abutments with titanium screws and torqued to 20 Ncm. Screw-access holes were filled, and no occlusal adjustment was necessary. The fit of the prosthesis was precise and stable, and the patient's phonetics were ideal. The patient was overwhelmed by the significant esthetic improvement with this set of teeth in place (Figure 6 through Figure 8).
Home care was reviewed with the patient, which included use of a toothbrush and water flosser. An antibiotic, amoxicillin 500 mg three times a day, as well as Motrin® 800 mg as needed, were prescribed. The patient was instructed to adhere to a soft diet and avoid hard food.
At 1-week postoperative, it was noted that the patient sustained very little postoperative pain, and home care and dietary suggestions were reviewed.
(Figure 8A through Figure 8I show integration confirmation at 6 months and a scan for a final prosthesis.)
A 60-year-old female patient presented with many periodontally and restoratively hopeless teeth that severely compromised esthetics and function and were inadequate to retain a maxillary restoration. She declined to advance into a full maxillary denture or partial denture. Existing maxillary teeth included Nos. 2 and 4 through 14 (Figure 9 and Figure 10). The opposing dentition was stable. The patient was in good health with no allergies to medication.
At the initial visit a panoramic x-ray (Figure 11) and periapical x-rays were taken. The patient was photographed to capture her full face and shoulders, and a digital scan (TRIOS 4) of the maxillary dentition was obtained. This file was electronically sent to the implant company (Osteon Medical) to complete the VSD.
A week later the patient presented for surgery for extraction and replacement of her existing maxillary dentition with implants and a screw-retained provisional implant restoration. Teeth Nos. 2, 4, 6 through 11, 13, and 14 were carefully extracted with attention paid to retaining site dimensions. Immediate implants (Paltop Dynamic Conical) were inserted into sites Nos. 4, 6, 8, 11, and 13 with high insertion torques in excess of 40 Ncm. Subsequently, multi-unit abutments were placed on all the implants and torqued to 30 Ncm, and scan gauges (Nexus iOS) were placed on implant Nos. 8 and 11 (Figure 12 and Figure 13).
A maxillary intraoral scan was obtained with a digital scanner (TRIOS 4) capturing the two remaining teeth in sites Nos. 5 and 12 and the scan gauges on implant Nos. 8 and 11. Subsequently, teeth Nos. 5 and 12 were extracted. Scan gauges were placed on implant Nos. 4, 6, and 13. At this time, another intraoral scan was captured of all the scan gauges on the five implants with the surrounding soft tissues (Figure 14 and Figure 15).
These files were electronically sent to the implant company (Osteon Medical) for AI calibration of the scan gauges, and then these files were incorporated into a VSD to create the ideal set of teeth for this patient that would precisely screw down onto the implants to restore the maxillary dentition. Restoration would encompass esthetics, function, and phonetics.
Several hours later the dental team received the STL file, from which they would print the maxillary prosthesis on a 3D printer (Pro 55S) using appropriately colored nanoceramic resin (OnX). The prosthesis was stained and glazed, and metal cylinders were inserted into the undersurfaces of the screw-access holes, each of which was specifically located to fit on the multi-unit abutments (Figure 16 and Figure 17).
The prosthesis fit precisely on the multi-unit abutments, and multi-unit screws were used to secure the prosthesis in place at 20 Ncm (Figure 18 through Figure 20). The screw-access holes were filled, and the patient was instructed in dietary restrictions and adherence to a soft diet. Instructions for oral hygiene were given, and the patient was advised to use a water flosser daily. Analgesics included Motrin 800 mg, and for antibiotics, amoxicillin 500 mg three times a day was prescribed.
Postoperative x-rays documented the full seating of the prosthesis on the multi-unit abutments (Figure 21 and Figure 22). The patient returned at 1-week postoperative for a follow-up visit and to review home care. She remarked that the restoration was comfortable and that she was free of discomfort and extremely pleased with the makeover she received in one day.
(Figure 22A through Figure 22L show integration confirmation at 6 months, bone healing, and the final prosthesis.)
A 67-year-old female patient presented with a highly compromised maxillary and mandibular dentition, including teeth Nos. 2 through 15, 17, 21 through 24, and 27 through 30. Soft tissues were of normal contour and bone profiles were generally sustained and favorable. The patient was excited about the prospect of transforming both her maxillary and mandibular compromised esthetics and function in one visit. (Case 3 is depicted in Figure 23 through Figure 42.)
At the initial appointment a panoramic x-ray and periapical x-rays were taken. As part of the protocol (Nexus iOS), photographs of the patient from head to shoulders were taken and scans of the teeth and soft tissue were captured with an intraoral scanner (TRIOS 4). These images were then sent electronically to the implant manufacturer (Osteon Medical), and three days later a VSD was provided for review and approval.
At the next visit the patient was anesthetized with xylocaine with 1:100,000 epinephrine. Teeth Nos. 22, 27, and 28 were retained and all other mandibular teeth were extracted. Immediate implants (Paltop Dynamic Conical) were placed in prosthetically correct positions and multi-unit abutments were torqued to 30 Ncm. This was followed by insertion of screw-retained scan gauges (Nexus iOS) in positions Nos. 18, 24, and 30.
In the maxillary arch, teeth Nos. 3, 7, 10, and 15 were retained and all other maxillary teeth were extracted. Immediate implants (Paltop Dynamic Conical) were placed prosthetically correctly with favorable insertion torques. Multi-unit abutments were placed on the implants and scan gauges were secured to these multi-unit abutments in sites Nos. 6, 8, and 11. An intraoral scan following the protocol captured the location of the implants with a reference to the remaining teeth and soft tissues. These files were then sent electronically to nexusios.com.
At the completion of surgery for the mandibular arch, teeth Nos. 17, 21 through 24, and 27 through 30 had been carefully extracted. Immediate implants with multi-unit abutments were placed in sites Nos. 21, 24, 28, and 30, and an additional implant with a multi-unit abutment was placed in site No. 18. All multi-unit abutments were torqued to 30 Ncm. In the maxillary arch, at the completion of surgery, teeth Nos. 2 through 15 had been carefully extracted. Immediate implants with multi-unit abutments were placed in sites Nos. 4, 6, 8, 11, and 13, and all multi-unit abutments were torqued to 30 Ncm.
The computer software (Osteon Medical) then calibrated the precise implant position based on a unique DME file that was assigned with the scan gauge kit (Nexus iOS) used for this procedure. The scan gauge data captured was used with proprietary AI software to establish exact multi-unit abutment positioning. The VSD designed presurgically was then incorporated with the surgical scan data provided by the surgeon. The multiplicity of algorithms was accessed until an optimum file was established that contained the prosthesis design for this dentition that would precisely fit, via screw retention, on the multi-unit abutments to secure a full-arch screw-retained provisional prosthesis.
This file was then electronically returned to the dental team via the nexusios.com portal. The office staff then sent the STL design file to the practice's 3D printer software (SprintRay), and the appropriate color nanoceramic resin was used to print the prosthesis at 100 microns. Once this was accomplished, the prosthesis was stained and glazed and gingival color was applied to establish optimum esthetics.
The completed prosthesis was then screwed directly onto the multi-unit abutments with Rosen screws with no ti-bases and torqued to 20 Ncm. Screw-access holes were filled, and no occlusal adjustment was necessary. The fit of the prosthesis was precise and stable and the phonetics of the patient was ideal. The patient was overwhelmed by the significant esthetic improvement with this set of teeth in place.
Home care was reviewed and included use of a toothbrush and water flosser. For an antibiotic, amoxicillin 500 mg three times a day was prescribed, along with Motrin 800 mg as needed as an analgesic. The patient was instructed to adhere to a soft diet and avoid hard food.
At the 1-week postoperative visit, it was noted that the patient sustained very little postoperative pain, and home care and dietary suggestions were reviewed.
A 71-year-old female patient presented with a maxillary complete denture and a failing mandibular dentition. The patient wore an ill-fitting mandibular acrylic removeable partial denture to supplement her periodontally compromised mandibular teeth. She expressed a desire to improve the esthetics and function of her teeth and to replace her removeable partial denture with a fixed prosthesis. (Case 4 is depicted in Figure 43 through Figure 52.)
An initial appointment included a complete oral examination as well as a panoramic x-ray, CBCT scan, and intraoral surface scans of her maxilla and mandible. A comprehensive treatment plan included extraction of her mandibular teeth with immediate implant placement and insertion of a mandibular full-arch immediate fixed provisional restoration followed by a final mandibular full-arch fixed zirconia restoration.
The treatment began by addressing the patient's immediate concern, which was her mandibular situation. Her mandibular teeth were extracted, and immediate implants were placed and immediately provisionalized using a screw-retained PMMA provisional, which sat on multi-unit abutments.
After 6 months of healing (the patient delayed her final restorative treatment), the mandibular final restorative procedure was begun. The Nexus iOS protocol and workflow was followed. The first appointment for the final restoration workflow consisted of a series of intraoral scans and full-face photography. The scans included the patient's maxillary denture, the mandibular temporary restoration that was seated in the patient's mouth, and the patient's bite.
The patient's mandibular temporary restoration was then removed from her mouth. A scan was taken of the mandibular multi-unit abutments and the surrounding soft tissue. Only the fixed soft tissue needed to be recorded, as only fixed tissue is repeatable. This type of intraoral scan is also known as the emergence profile scan.
Three implant scan bodies designed to replicate the multi-unit abutment position in the temporary were affixed to the fixed provisional restoration in the multi-unit positions with multi-unit screws. The positions were chosen to create a wide anterior-to-posterior spread. The provisional restoration with the implant scan bodies was then scanned 360 degrees.
The scan gauges were then placed onto the mandibular multi-units in the patient's mouth and retained with multi-unit screws. The choice of scan gauge height and lengths was per the Nexus iOS protocol. Two intraoral scan gauge scans were taken. The first was done in a right to left pass over the scan gauges, with care exercised to move forward in an arc so as not to go back over already-scanned segments. A second independent scan was done in a left to right arc, again with care taken not to scan any segment twice in the same scan. This completed the series of intraoral scans required to produce the restoration.
A full-face photograph was taken with the patient's upper and lower prostheses in place. This completed all the data required for the final prosthesis design.
This series of intraoral scans with the full-face photograph was uploaded to the Nexus iOS portal with all questions regarding the case requirements answered. The provisional prosthesis had been carefully designed and the request in the prescription was to duplicate the provisional design. The patient had been wearing this provisional for several months, so phonetics, esthetics, function, and occlusion had been well tested. This completed the prescription phase of the case, including sending the required data.
Four days later, the clinician received an email from Osteon Medical requesting approval of the prosthesis design. Upon opening the email, a tool showing the proposed 3D design of the prosthesis was activated. All aspects of the prosthesis design were analyzed in three dimensions. Upon review of the design proposal and confirmation of the duplication of the provisional prosthesis design, approval was given to move forward with the final prosthesis fabrication.
Two weeks after design approval was given, the dental office received the final prosthesis. Included in the packaging were the final prosthesis, new multi-unit screws, oral hygiene aids appropriate for patient use with this type of prosthesis, and a warranty card.
When the patient presented for insertion of the final prosthesis the provisional prosthesis was removed, and the final prosthesis was inserted onto the multi-unit abutments. One multi-unit screw was placed with hand tightening in the most distal position on the patient's left side. Periapical radiographs were taken paralleling the multi-unit abutment to the final prosthesis joint to confirm complete passive seating of the restoration. After confirming that the restoration sat passively and completely on the multi-unit abutments, the remainder of the multi-unit screws were inserted, and all were torqued to 20 Ncm using a torque driver. The occlusion was then evaluated; this included checking centric contact points as well as for lateral excursive and protrusive guidance.
The patient was then shown her new smile, and she approved of the comfort and esthetics of the restoration. Screw-access holes were filled with Teflon tape and covered with a flowable composite resin, completing the insertion visit. The final prosthesis fulfilled the needs for passive fit, favorable esthetics, occlusion, and phonetics.
There continues to be a substantial North American population in need of full-arch dental implant-supported rehabilitation for both edentulous and partially edentulous dentitions.22-23 Techniques used to treat these patients begin at the diagnostic stage, continue through the surgical stage, and are finalized in the definitive prosthetic restoration.
There are multiple approaches to the surgical phase. The surgical approach used will influence the progression sequence of the case and the trauma sustained by the patient. Flapless immediate implant surgery was the protocol used in the cases documented here.
In this immediate implant surgical protocol, remaining teeth are extracted as atraumatically as possible preserving bone and soft-tissue landmarks. This approach is key to site preservation.8,11,19 Implant placement resulting in high insertion torques of 35 Ncm to 50 Ncm and in some sites 70 Ncm is accomplished by judicious site preparation and titration of insertion torque of the implants until high insertion torques are achieved.19 In some sites, milling of the bone is done to ensure accurate and full seating of multi-unit abutments. In all sites, the implants are placed in the best available bone and are prosthetically correct to the existing opposing or planned opposing dentition.
In conventional prosthetic procedures, upon completion of the surgery, multiple visits are typically required over many months, during which time the patient may be in a removeable prosthesis.24 Immediate implant provisionalization in full-arch restorations has been well documented to be highly successful with good clinical outcomes and is patient preferred.25,26 Conventional prosthetic workflows may require analog impressions at the time of surgery with the pouring of stone models. The immediate provisional restoration may need direct relining of a conversion prosthesis intraorally immediately following implant surgery.27 These procedures require considerable expertise to achieve precise fit and proper occlusion and demand significant patient chairside time and intraoral manipulation.28 This approach can be challenging for both the clinician and patient after a tedious surgical procedure.29
A simple expeditious digital workflow as described here allows accurate digital recording of implant position and delivery of the provisional restoration in a timely manner on the day of surgery with minimal involvement intraorally. Accurate digital capture of implant position for full-arch implant-supported restorations had previously been reported to be less than precise.30,31 This protocol provides a predictable means for fabrication of the provisional restoration on the day of implant surgery and shortens treatment time and chairside challenges for both the clinician and patient.
The benefit of the digital workflow is even more pronounced in the fabrication of the final restoration. Commonly required steps for conventional fabrication and delivery of a final restoration include accurately recording the implant position, opposing arch, vertical dimension, and centric occlusal record. The model (analog or virtual) must be accurate to a level that can predictably produce a passively seated restoration. To assure accuracy and passive fit, a verification step and verification jig are frequently utilized. The clinician then must transfer the esthetic, phonetic, and restorative requirements for the final prosthesis to the laboratory. This is usually followed by final prosthesis fabrication and clinical insertion. Conventional techniques today require five to six patient appointments to produce an accurate, passively fitting prosthesis.32-34
The solution for prosthetic rehabilitation of the full-arch implant patient discussed here addresses the complexity of full-arch restoration by using a simple repeatable digital workflow. As few as two appointments may be needed to restore a full arch of implants with a fixed implant-supported restoration. If a prosthesis design try-in is required, it can be done by downloading and 3D printing the STL file of the designed final prosthesis. A three-appointment protocol is then required to incorporate the try-in of the printed prosthesis design. Phonetics, esthetics, and occlusion can be evaluated, and if there are any adjustments made, a simple scan of the modified try-in prosthesis is recorded and uploaded to the manufacturer portal. An immediate provisional as well as a try-in prosthesis can be implemented in the same day with 3D printing technology.
This protocol overcomes the difficulties of producing accurate passive restorations through novel AI-empowered geometric scan abutment designs, optimization of manufacturing tolerances to eliminate errors in the rendering of virtual implant position, implant position optimization software algorithms, and AI analysis and design software for prosthesis design. The final prosthesis has a milled titanium bar to support the veneering material, which may be monolithic zirconia, monolithic zirconia layered with porcelain, or a milled bar veneered with acrylic. The restoration design, including the titanium milled bar and veneering material, may be as small as 6 mm in height from the soft tissue to the incisal edge.35
Having the ability to fabricate a full-arch prosthesis with a vertical thickness requirement reduced to 6 mm36 may eliminate the need for bone reduction for the purpose of structural integrity of the final prosthesis and, thus, eliminate the trauma of ridge reduction surgery. Occasionally, bone reduction may still be necessary to move the transition zone out of the smile line. However, if bone reduction is not necessary for restoration strength, the number of esthetic-zone transition issues is significantly reduced. Many cases that would have needed pink aprons to manage excessive tooth length and esthetic transition zones can now be managed with a crown-and-bridge style prosthesis with esthetic dimensioned teeth emerging from the patient's natural soft tissue. The prosthesis design that allows this minimal restoration thickness and good restoration strength is accomplished through a unique software design program that incorporates AI that applies structural mechanical engineering principles to dental restoration design.
With this protocol, the restorations seat on multi-unit abutments and are available for most commonly used multi-unit systems. The restoration interface to the multi-unit abutment is through the titanium bar milled directly to the multi-unit abutment interface. No ti-bases are used, so potential errors from cementing a ti-base improperly, or the ti-base becoming uncemented, are eliminated.
Implant capture accuracy is predictably accomplished in this fully digital workflow. Previously, the digital capture of implant position for full-arch implant-supported restorations had reported limitations in accuracy.30,31 Many variables affect the production of an accurate virtual model, including the type of intraoral scanner used, geometric design of the scan body, scan body material, whether the scan body is one-piece or two-piece, position of the scan bodies, manufacturing tolerances of the scan bodies, scanning strategy, and operator experience.36-46 The full-arch solution described here uses a complete digital workflow that addresses accuracy issues of intraoral scanner type, scanning strategies, manufacturing tolerances of intraoral scan bodies, effect of implant and scan body position, scan body material, novel scan body design, and clinician experience. The manufacturer has demonstrated an average implant-to-implant linear discrepancy of sub-10 microns, which meets the requirement for a passively seating restoration.34,47-49 As a total solution, the recording of centric relation, vertical dimension, and transfer of prosthesis design parameter is accomplished within the scanning protocol. The use of AI algorithms, innovative design, careful clinical workflow strategies, and rigorous manufacturing procedures supports both the full-arch immediate implant provisionalization procedures as well as the final restorative solution.
The simple workflow uses basic intraoral scans for the fabrication of the immediate full-arch implant-supported provisional restoration thereby eliminating the steps of intraoral manipulation required for immediate provisional restoration fabrication during implant surgery. The efficiency of this solution continues with the production of a highly accurate, predictable final restoration in two to three appointments.
A digital workflow was presented using proprietary, highly accurate scan bodies, an innovative clinical protocol, and proprietary AI software resulting in the delivery of a passively fitting screw-retained 3D-printed provisional prosthesis on the day of implant surgery. This is followed by a proprietary restorative protocol resulting in efficient fabrication and insertion of the final prosthesis. These sequences represent a new standard of care in implant dentistry.
The authors acknowledge Donald Boyd and Dr. Michael Klein for their educational leadership in the launch of the Nexus iOS protocol; Melker Nilsson for selecting the author (DAG) in the initial launch of this discipline; Dr. Jonathan J. Gelb for his initiative and participation in the integration of this protocol into the author's (DAG) office; Christian Villarroel for equipment procurement; Terry Spaulding, Alexis Pantaleo, Donald Boyd, Dana Tatta, Vince Lancenese, and Tim Steinglass for their assistance in delivery of surgical and prosthetic care; Drs. Jeffrey Burns, Scott Merkelson, and Peter Sawka for their collaboration in Cases 1 through 3. Surgery and prosthetics were provided by Dr. David A. Gelb in Cases 1 through 3 and Dr. Michael Klein in Case 4.
David A. Gelb, DDS, is a lecturer and consultant for Keystone Dental Group; Michael Klein, DDS, is Chief Technology Officer, Keystone Dental Group; Michael Tuckman is Founder and President, Osteon Medical.
ABOUT THE AUTHORS
David A. Gelb, DDS
Diplomate, American Academy of Periodontology; Fellow, Academy of Osseointegration; Fellow, American College of Dentists; Fellow, International College of Dentists; Fellow, Pierre Fauchard Academy; Private Practice, West Hartford, Connecticut
Michael Klein, DDS
Chief Technology Officer, Keystone Dental Group, Burlington, Massachusetts; Former Clinical Associate Professor, Department of Periodontology and Implant Dentistry, New York University College of Dentistry, New York, New York;Diplomate, American Board of Oral Implantology/Implant Dentistry; Diplomate, International Congress of Oral Implantology; Fellow, Academy of Osseointegration; Private Practice, Cedarhurst, New York
Founder, President, Osteon Medical, Melbourne, Australia
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