CASE REPORT

Minimally Invasive Implant Surgery and Immediate Loading:Surgical and Prosthetic Techniques

Harold S. Baumgarten*† and Badr Othman‡

Introduction: Computerized tomography (CT)–guided implant surgery has been used to perform minimally invasiveimplant placement. In many cases, the procedure may be performed along with immediate restoration. Inaccuracies relatedto the CT scan itself and the surgical technique often result in implant positions which are slightly different from those thatwere planned. If immediate restoration and/or loading is desired, a prosthetic technique must be used that can easilyaccount for this discrepancy.

Case Presentation: A 43-year-old male patient with a completely edentulous maxilla andmandible presented to thePeriodontics Clinic at the University of Pennsylvania. Implants were placed in both the maxilla and mandible using a mini-mally invasive CT-guided approach. The dentures that were fabricated for him were converted into fixed hybrid restorationsat the time of surgery using two different techniques that took into account any discrepancy between the surgical plan andthe actual placement.

Conclusions:With meticulous planning and appropriate prosthetic technique, CT-guided surgery can be usedto perform minimally invasive implant surgery and immediate restoration of edentulous jaws. This approach can pro-vide lower morbidity along with a more accurate, fast, and convenient result for the patient. Clin Adv Periodontics2013;3:89-94.

Key Words: Dental implants; immediate dental implant loading.

BackgroundThe patient, a 43-year-old male, became edentulous at anearly age. He voiced his anxiety regarding dental visits,

and after discussions with the treatment team, it becameobvious that a minimally invasive surgical approach wouldbe preferable. In addition, any technique that would mini-mize postoperative visits, such as denture adjustments andrelines, would also be beneficial. This led the team to selectimmediate restoration and loading.

The accuracy of computerized tomography (CT)–guidedsurgery has been covered extensively in the dental litera-ture.1 Although CT-guided surgery is more accurate thantraditional approaches,2 there are errors in the techniqueitself that are difficult to avoid. One source of error is theCT itself; there is a discrepancy between the actual size of

* Department of Periodontics, University of Pennsylvania, Philadelphia, PA.

† Private practice, Amsterdam Dental Group, Philadelphia, PA.

‡ Resident in Periodontics and Periodontal Prosthesis, Department ofPeriodontics, University of Pennsylvania.

Submitted August 6, 2012; accepted for publication October 30, 2012

doi: 10.1902/cap.2013.120084

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the jaw and its size in the scan.3 There may also be a dis-crepancy between the implant location in the plan andthe placement related to the surgical technique.4 Thismakes fabricating a screw-retained provisional restora-tion based on the implant location in the surgical plan5

challenging.

The majority of the authors’ past experience with imme-diate loading of edentulous jaws involves placement of anadequate number of implants and abutments and incorpo-rating screw-retained temporary cylinders into a patient’sexisting satisfactory denture at the time of surgery. Themost time-consuming part of the technique involves locat-ing the abutment positions inside the denture and drillingholes to accommodate the temporary cylinders. This caseillustrates two different methods for fabricating models

FIGURE 1 Patient’s edentulous maxilla.

FIGURE 2 Patient’s edentulous mandible.

FIGURE 3 New dentures fabricated to determine tooth position, smilingesthetics, occlusion, phonetics, and lip support.

FIGURE 4 Dentures duplicated as scanning appliances with radiopaquemarkers.

FIGURE 5 Three-dimensional images showing maxillary and mandibularsurgical plans.

FIGURE 6 Maxillary surgical guide with analogs on analog mounts.

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of the planned implant positions prior to surgery. This fa-cilitates modification of the patient’s dentures prior to sur-gery, greatly reducing the time it takes to complete the fixedprovisional restoration at the time of surgery.6

Clinical PresentationThe patient, a fully edentulous 43-year-old male, presentedto the Graduate Periodontics Clinic at the University ofPennsylvania School of Dental Medicine in September2008, in excellent health desiring fixed prosthetic recon-struction (Figs. 1 and 2). The patient gave written informedconsent for treatment and to be profiled. The treatmentdocumented in this article was performed in June 2012.

Case ManagementTo adequately plan the treatment for this patient, new den-tures (Fig. 3) were fabricated. In this manner, tooth position,smiling esthetics, and proper implant position could be

determined. The now satisfactory dentures were duplicatedinclearorthodontic resin incorporating radiopaqueglassbeads(Fig. 4). The duplicate dentureswereworn by the patient duringthe exposure of the CTscan. A dual scan approach6 was used.

The DICOM (Digital Imaging and Communications inMedicine) files from the CT scan were imported into

FIGURE 7 Completed maxillary master cast.

FIGURE 8 Mandibular stereolithographic model with implant analogsretained by set screws.

FIGURE 9 Mounted master casts.

FIGURE 10 Maxillary denture on master cast prepared for conversion intofixed hybrid prosthesis. Note preprepared holes for luting of temporarycylinders at time of implant placement.

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implant-planning software. Virtual implants and fixationscrews were placed in the plan (Fig. 5), and the surgicalguides were ordered.

To illustrate the different techniques that may be used tofabricate a master cast, the maxilla and mandible weremanaged differently. A master cast for the maxilla wasfabricated by mating implant analogs with analog mountsand inserting them into the surgical guide (Fig. 6). A stonecast was then poured in the dental laboratory (Fig. 7).A master cast for the mandible was fabricated using a

stereolithographic technique. The model incorporatessites for implant analogs as well as set screws for fixingthe analogs to themodel (Fig. 8). Thismethod avoids a sep-arate laboratory procedure to procure a master cast. Themaster casts were articulated using the clear duplicatedentures (Fig. 9).

Prior to surgery, the patient’s dentures were withheldand brought to the laboratory where sites were preparedfor the temporary cylinders (Figs. 10 and 11).

Treatment was performed in two sessions. The maxillawas treated during the first session and the mandible duringthe second. In each session, the patient was anesthetizedwith 2%xylocainewith 1:100,000 epinephrine. Before fix-ing the guide, a guided tissue punch was used to excisea plug of soft tissue at each implant site (Video 1). Minimalzones of keratinized tissue would be addressed in the man-dible after implant integration, if necessary. The guideswere fixed using 13-mm-long bone screws (Video 2).

A series of guided drills and bone taps were used to pre-pare the osteotomies (Video 3). The implants were thenplaced through the surgical guide using guided implantmounts (Video 4).

FIGURE 11 Mandibular denture on master cast prepared for conversioninto fixed hybrid prosthesis. Note preprepared holes for luting of temporarycylinders at time of implant placement and the prepunched rubber dam.

FIGURE 12 Rubber dam retained by mandibular temporary cylinders.

FIGURE 13 Completed maxillary and mandibular provisional prostheses.

FIGURE 14 Completed maxillary and mandibular provisional prostheses.

FIGURE 15 Pretreatment and post-treatment panoramic radiographs.

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The implant mounts and surgical guide were removed.Low-profile conical abutments were placed and torquedto 20 Ncm. Temporary cylinders were fixed to the abut-ments with gold prosthetic screws. A rubber dam wasplaced such that each temporary cylinder protrudedthrough it, thus isolating the surgical site from the restor-ative material (Fig. 12). The previously prepared denturewas placed in the mouth and luted to the temporary cylin-ders with denture repair acrylic (Video 5). After the repairacrylic had polymerized, the occlusion was refined and theprosthesis was unscrewed and finished in the laboratory(Fig. 13). The completed provisional restorations wereplaced intraorally and retained with gold prostheticscrews. The screw access holes were sealed with temporaryrestorativematerial (Fig. 14). The patient was instructed toeat a soft diet and was prescribed an antimicrobial rinse,antibiotic, and analgesic. Healing proceeded unevent-fully (Fig. 15).

Clinical OutcomesA fully edentulous patient received complete maxillaryand mandibular fixed provisional restorations retained byimplants that were placed using a minimally invasive sur-gical technique. Advanced preparation allows treatmenttime and trauma to be minimized, thereby reducing mor-bidity for the patient.

DiscussionMany clinicians feel that CT-guided surgery is accurateenough for the fabrication of a completed screw-re-tained prosthesis for placement at the time of surgery,5

but other investigators point to the relative inaccuracyof this approach.1 The use of a prosthetic technique thatrelates the abutments to the prosthesis at the time of sur-gery negates any possible inaccuracy related to the scanor surgical technique and results in a passively fittingrestoration. n

Summary

Why is this case new information? j It illustrates how treatment time and patient morbidity can beminimized with advanced surgical and prosthetic techniques.

What are the keys to successfulmanagement of this case?

j Understanding that CT-guided surgery is not precise enough tocompletely fabricate a restoration for placement at the time ofsurgery.

What are the primary limitations tosuccess in this case?

j One limitation is the relative inaccuracy of CT guidance.

AcknowledgmentsDr. Baumgarten has received financial support for researchand consulting and advisor fees from Biomet 3i (PalmBeach Gardens, Florida). Dr. Othman reports no conflictsof interest related to this case report.

CORRESPONDENCE:Dr. Harold S. Baumgarten, 100 S. Broad St., Suite 2000, Philadelphia, PA19110. E-mail: hbaumgarten@4dentistry.com.

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References1. Vercruyssen M, Jacobs R, Van Assche N, van Steenberghe D. The use of

CT scan based planning for oral rehabilitation by means of implantsand its transfer to the surgical field: A critical review on accuracy. J OralRehabil 2008;35:454-474.

2. Sarment DP, Sukovic P, Clinthorne N. Accuracy of implant placementwith a stereolithographic surgical guide. Int J Oral Maxillofac Implants2003;18:571-577.

3. LoubeleM, VanAsscheN, Carpentier K, et al. Comparative localized linear ac-curacy of small-field cone-beamCTandmultislice CT for alveolar bonemeasure-ments.Oral SurgOralMedOral PatholOral Radiol Endod 2008;105:512-518.

4. Van Assche N, van Steenberghe D, Guerrero ME, et al. Accuracy ofimplant placement based on pre-surgical planning of three-di-mensional cone-beam images: A pilot study. J Clin Periodontol2007;34:816-821.

5. Marchack CB. An immediately loaded CAD/CAM-guided definitiveprosthesis: A clinical report. J Prosthet Dent 2005;93:8-12.

6. Rosenfeld AL, Mandelaris GA, Tardieu PB. Prosthetically directedimplant placement using computer software to ensure precise place-ment and predictable prosthetic outcomes. Part 3: Stereolithographicdrilling guides that do not require bone exposure and the immediatedelivery of teeth. Int J Periodontics Restorative Dent 2006;26:493-499.

indicates key references.

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