Immediately loaded CAD-CAM manufactured fixed complete dentures using flapless implant placement procedures: a cohort study of consecutive patients

Post-thermocycling shear bond strength of a gingiva-colored indirect composite layering material to three implant framework materials

OBJECTIVE

To evaluate shear bond strength of a gingiva-colored indirect composite to three implant framework materials, before and after thermocycling, and verify the effect of surface pre-treatment for each framework.

MATERIALS AND METHODS

Commercially pure titanium (CP-Ti), American Dental Association (ADA) type 4 casting gold alloy (Type IV) and zirconia ceramics (Zirconia) were assessed. For each substrate, 96 disks were divided into six groups and primed with one of the following primers: Alloy Primer (ALP), Clearfil Photo Bond (CPB), Clearfil Photo Bond with Clearfil Porcelain Bond Activator (CPB+Activator), Estenia Opaque Primer (EOP), Metal Link (MLP) and V-Primer (VPR). The specimens were then bonded to a gingiva-colored indirect composite (Ceramage Concentrate GUM-D). Shear bond strengths were measured at 0 and 20 000 thermocycles and data were analyzed with the Steel-Dwass test and Mann-Whitney U-test.

RESULTS

Shear bond strengths were significantly lower after thermocycling, with the exception of Type IV specimens primed with CPB (p = 0.092) or MLP (p = 0.112). For CP-Ti and Zirconia specimens, priming with CPB or CPB+Activator produced significantly higher bond strengths at 0 and 20 000 thermocycles, as compared with the other groups. For Type IV specimens, priming with ALP or MLP produced higher bond strengths at 0 and 20 000 thermocycles.

CONCLUSIONS

Shear bond strength of a gingiva-colored indirect composite to CP-Ti, gold alloy and zirconia ceramics was generally lower after thermocycling. Application of a hydrophobic phosphate monomer and polymerization initiator was effective in maintaining bond strength of CP-Ti and zirconia ceramics. Combined use of a thione monomer and phosphoric monomer enhanced the durable bond strength of gold alloy.

Coverage of denture teeth with tin foil for radiographic guide fabrication

A novel technique using the patient's existing complete dentures as a radiographic guide for diagnosis and treatment planning in implant dentistry is presented. Tin foil is used to cover the denture teeth before the radiographic scan is performed. Advantages of the described technique include its cost-effectiveness, simplicity, efficiency, and lack of need to modify or duplicate the patient's existing dentures. A disadvantage of the technique is that it serves only as a radiographic guide.

Implant Restoration of Edentulous Jaws with 3D Software Planning, Guided Surgery, Immediate Loading, and CAD-CAM Full Arch Frameworks

Purpose. The aim of this study was to analyze the clinical and radiographic outcomes of 23 edentulous jaws treated with 3D software planning, guided surgery, and immediate loading and restored with CAD-CAM full arch frameworks. Materials and Methods. This work was designed as a prospective case series clinical study. Twenty patients have been consecutively rehabilitated with an immediately loaded implant supported fixed full prosthesis. A total of 120 fixtures supporting 23 bridges were placed. 117 out of 120 implants were immediately loaded. Outcome measures were implants survival, radiographic marginal bone levels and remodeling, soft tissue parameters, and complications. Results. 114 of 117 implants reached a 30 months follow-up, and no patients dropped out from the study. The cumulative survival rate was 97.7%; after 30 months, mean marginal bone level was 1.25 ± 0.31 mm, mean marginal bone remodeling value was 1.08 ± 0.34, mean PPD value was 2.84 ± 0.55 mm, and mean BOP value was 4% ± 2.8%. Only minor prosthetic complications were recorded. Conclusion. Within the limitations of this study, it can be concluded that computer-guided surgery and immediate loading seem to represent a viable option for the immediate rehabilitations of completely edentulous jaws with fixed implant supported restorations. This trial is registered with Clinicaltrials.gov NCT01866696.

Types of Implant Surgical Guides in Dentistry: A Review

Various techniques have been proposed for the fabrication of surgical guide templates in implant dentistry. The objective of this paper is to review the associated literature and recent advancements in this field, based on design concept. An electronic and hand search of the literature revealed 3 categories, namely, nonlimiting, partially limiting, and completely limiting design. Most clinicians still adopt the partially limiting design due to its cost-effectiveness and credibility. Moreover, clinicians use cross-sectional imaging during the preimplant assessment of surgical sites.

A new surgical template with a handpiece positioner for use during flapless placement of four dental implants to retain a mandibular overdenture

This article describes the fabrication of a new and inexpensive surgical template from a radiographic template for flapless placement of dental implants to retain a mandibular overdenture. A radiographic template with radiopaque metal plate markers is constructed and used as a guide for achieving three-dimensional evaluation of bone using computed tomography (CT). The potential position and angulation of the implants are measured relative to the metal plates using the CT data. The radiographic template is converted into a surgical template by attaching rigid metal rods that guide the handpiece precisely during subsequent drilling procedures.

Standard of disocclusion in complete dentures supported by implants without free distal ends: analysis by the finite elements method

OBJECTIVE

The occlusal patterns are key requirements for the clinical success of oral rehabilitation supported by implants. This study compared the stresses generated by the disocclusion in the canine guide occlusion (CGO) and bilateral balanced occlusion (BBO) on the implants and metallic infrastructure of a complete Brånemark protocol-type denture modified with the inclusion of one posterior short implant on each side.

MATERIAL AND METHODS

A three-dimensional model simulated a mandible with seven titanium implants as pillars, five of them installed between the mental foramen and the two posterior implants, located at the midpoint of the occlusal surface of the first molar. A load of 15 N with an angle of 45° was applied to a tooth or distributed across three teeth to simulate the CGO or BBO, respectively. The commercial program ABAQUS® was used for the model development, before and after the processing of the data. The results were based on a linear static analysis and were used to compare the magnitude of the equivalent stress for each of the simulations.

RESULTS

The results showed that the disocclusion in CGO generated higher stresses concentrated on the working side in the region of the short implant. In BBO, the stresses were less intense and more evenly distributed on the prosthesis. The maximum stress found in the simulation of the disocclusion in CGO was two times higher than that found in the simulation of the BBO. The point of maximum stress was located in the neck of the short implant on the working side.

CONCLUSIONS

Under the conditions of this study, it was concluded that the BBO pattern was more suitable than CGO for the lower complete denture supported by implants without free distal ends.

Optimization of cone beam CT exposure for pre-surgical evaluation of the implant site

OBJECTIVES

The aim of this study was to investigate the possibility of reducing patient X-ray dose in the course of implant site evaluation.

METHODS

Retrospective practice-based study using a Morita F170 Accuitomo cone beam CT (CBCT) scanner with variable exposure parameters and operating a small cylindrical field of view of 4 cm diameter and 4 cm height. 6 experienced dental surgeons scored the image quality of dental scans on a 5-point scale for adequacy in providing the required information in 2 categories: bone height from alveolar crest to the relevant anatomical structure and bone width.

RESULTS

Lower-dose protocols only marginally affected the preference of the reviewers of the resulting images.

CONCLUSIONS

There is potential to reduce patient dose very significantly in CBCT examinations for implant site evaluation.

A single appointment protocol to create a partially edentulous CAD/CAM guided surgical template: a clinical report

The traditional technique for creating a CAD/CAM surgical template with a NobelGuide protocol is to fabricate a radiographic template that depicts the planned tooth position first. Multiple appointments are needed for the fabrication of the radiographic template with Cone Beam Computed Tomography (CBCT) before the surgical procedure can start. An alternative technique is described for fabricating a radiographic template at the initial examination appointment and capturing the necessary DICOM data to plan and fabricate a CAD/CAM surgical template in a 1-appointment protocol, thereby saving the patient and clinician time and reducing the need for multiple appointments.

Accuracy and complications of computer-designed selective laser sintering surgical guides for flapless dental implant placement and immediate definitive prosthesis installation

BACKGROUND

Computer-aided dental implant placement seems to be useful for placing implants by using a flapless approach. However, evidence supporting such applications is scarce. The aim of this study is to evaluate the accuracy of and complications that arise from the use of selective laser sintering surgical guides for flapless dental implant placement and immediate definitive prosthesis installation.

METHODS

Sixty implants and 12 prostheses were installed in 12 patients (four males and eight females; age range: 41 to 71 years). Lateral (coronal and apical) and angular deviations between virtually planned and placed implants were measured. The patients were followed up for 30 months, and surgical and prosthetic complications were documented.

RESULTS

The mean ± SD angular, coronal, and apical deviations were 6.53° ± 4.31°, 1.35 ± 0.65 mm, and 1.79 ± 1.01 mm, respectively. Coronal and apical deviations of <2 mm were observed in 82.67% and 58.33% of the implants, respectively. The total complication rate was 34.41%; this rate pertained to complications such as pulling of the soft tissue from the lingual surface during drilling, insertion of an implant that was wider than planned, implant instability, prolonged pain, midline deviation of the prosthesis, and prosthesis fracture. The cumulative survival rates for implants and prostheses were 98.33% and 91.66%, respectively.

CONCLUSIONS

The mean lateral deviation was <1.8 mm, and the mean angular deviation was 6.53°. However, 41.67% of the implants had apical deviation >2 mm. The complication rate was 34.4%. Hence, computer-aided dental implant surgery still requires improvement and should be considered as in the developmental stage.

Immediate loading of the maxilla with prefabricated interim prosthesis using interactive planning software, and CAD/CAM rehabilitation with definitive zirconia prosthesis: 2-year clinical follow-up

Immediate loading in implant dentistry has provided several advantages for both patients and clinicians. Recent advances in computer-aided design/computer-aided manufacturing (CAD/CAM) technology, medical imaging and rapid prototyping have added to the armamentarium of implant dentistry in terms of efficiency, accuracy and predictability. Rapid prototyping and CAD/CAM technology are used to fabricate stereolithographic surgical templates for flapless implant placement. In addition to that, this technology is also used for the fabrication of zirconia frameworks. The zirconia-based implant restorations are gaining popularity in implant prosthodontics combining esthetic properties with strength and biocompatibility. The purpose of this article is to illustrate the steps for implant rehabilitation of the edentulous maxilla with zirconia prosthesis and report the 2-year clinical follow-up of novel technological advances in surgical placement, provisionalization and fabrication of a definitive restoration.

CLINICAL SIGNIFICANCE

A comprehensive approach to full mouth implant rehabilitation using cutting edge technology is illustrated in a simplified manner.

A technique for indirect fabrication of a complete-arch, implant-supported, fixed provisional restoration from a radiographic template

This article describes an alternative technique for the fabrication of a complete-arch, implant-supported, cement-retained, fixed provisional restoration. The definitive cast is fabricated from the surgical guide and the provisional restoration is fabricated indirectly from the radiographic guide. This technique is an easy and time-saving procedure to fabricate an interim prosthesis for immediate or delayed loading of implants.

Accuracy assessment of computer-assisted flapless implant placement in partial edentulism

AIM

To assess the accuracy of implants placed flapless by a stereolithographic template in partially edentulous patients.

MATERIAL AND METHODS

Eight patients, requiring two to four implants (maxilla or mandible), were consecutively recruited. Radiographical data were obtained by means of a cone beam or a multi-slice CT scan and imported in a software program. Implants (n=21) were planned in a virtual environment, leading to the manufacture of one stereolithographic template per patient to guide the implant placement in a one-stage flapless procedure. A postoperative cone beam CT was performed to calculate the difference between virtual implant (n=21) positions in the preoperative planning and postoperative situation.

RESULTS

A mean angular deviation of 2.7 degrees (range 0.4-8, SD 1.9), with a mean deviation at the apex of 1.0 mm (range 0.2-3.0, SD 0.7), was observed. If one patient, a dropout because of non-conformity with the protocol, was excluded, the angular deviation was reduced to 2.2 degrees (range 0.6-3.9, SD 1.1), and the apical deviation to 0.9 mm (range 0.2-1.8).

CONCLUSION

Based on this limited patient population, a flapless implant installation appears to be a useful procedure even when based on accurate and reliable 3D CT-based image data and a dedicated implant planning software.

Accuracy evaluation of computed tomography-derived stereolithographic surgical guides in zygomatic implant placement in human cadavers

Presurgical planning is essential to achieve esthetic and functional implants. For implant planning and placement, the association of computer-aided design (CAD) and computer-aided manufacturing (CAM) techniques furnishes some advantages regarding tridimensional determination of the patient's anatomy and fabrication of both anatomic models and surgical guides. The goal of this clinical study was to determine the angular deviations between planned and placed zygomatic implants using stereolithographic surgical guides in human cadavers. A total of 16 zygomatic implants were placed, 4 in each cadaver, with the use of stereolithographic (SLA) surgical guides generated by computed tomography (CT). A new CT scan was made after implant insertion. The angle between the long axis of the planned and actual implants was calculated. The mean angular deviation of the long axis between the planned and placed implants was 8.06 ± 6.40 (mean ± SD) for the anterior-posterior view, and 11.20 ± 9.75 (mean ± SD) for the caudal-cranial view. Use of the zygomatic implant, in the context of this protocol, should probably be reevaluated because some large deviations were noted. An implant insertion guiding system is needed because this last step is carried out manually. It is recommended that the sinus slot technique should be used together with the CT-based drilling guide to enhance final results. Further research to enhance the precision of zygomatic implant placement should be undertaken.

Accuracy of virtually planned and template guided implant surgery on edentate patients

PURPOSE

Scientific evidence regarding the accuracy of implants placed into patients by the aid of a surgical template is limited. The objective of the present study was to verify if any variation exists between virtually planned implants' position using a computer, compared with the subsequently clinically placed implants with the aid of a surgical template in the mandible and the maxilla.

MATERIAL AND METHODS

A total number of 25 edentate jaws were treated with the aid of a surgical template. In total, 139 implants were inserted. Fifty implants were inserted in the mandible and 89 in the maxilla. A voxel-based registration method was used to match two separate cone-beam computed tomography scans of the patients. The implant positions were calculated and compared between the planned implants and the implants' clinical position after more than 1 year after surgery. The results included the linear differences in distance at the level of the hex, the apex, and the depth. The angular differences were presented in degrees.

RESULTS

Statistical results indicated some factors with significant deviations. The greatest errors were found when comparing between patients moving during the computed tomography scans and those that did not move. The results showed significant divergence at the level of the hex and apex of the implants.

CONCLUSION

The hypothesis was rejected, as the statistical results indicated that there were significant differences between virtually planned implants' position and the final position of implants placed clinically.

Accuracy and complications using computer-designed stereolithographic surgical guides for oral rehabilitation by means of dental implants: a review of the literature

BACKGROUND

In the last decade several stereolithographic guided surgery systems were introduced to the market. In this context, scientific information regarding accuracy of implant placement and surgical and prosthodontical complications is highly relevant as it provides evidence to implement this surgical technique in a clinical setting.

PURPOSE

To review data on accuracy and surgical and prosthodontical complications using stereolithographical surgical guides for implant rehabilitation.

MATERIAL AND METHODS

PubMed database was searched using the following keywords: "three dimensional imaging,""image based surgery,""flapless guided surgery,""customized drill guides,""computer assisted surgery,""surgical template," and "stereolithography." Only papers in English were selected. Additional references found through reading of selected papers completed the list.

RESULTS

In total 31 papers were selected. Ten reported deviations between the preoperative implant planning and the postoperative implant locations. One in vitro study reported a mean apical deviation of 1.0 mm, three ex vivo studies a mean apical deviation ranging between 0.6 and 1.2 mm. In six in vivo studies an apical deviation between 0.95 and 4.5 mm was found. Six papers reported on complications mounting to 42% of the cases when stereolithographic guided surgery was combined with immediate loading.

CONCLUSION

Substantial deviations in three-dimensional directions are found between virtual planning and actually obtained implant position. This finding and additionally reported postsurgical complications leads to the conclusion that care should be taken whenever applying this technique on a routine basis.

Radiographic and surgical guide fabrication for implant-retained mandibular overdenture

A simple technique is presented to make a multipurpose duplicate of the patient's complete denture to plan and fabricate a mandibular implant-retained overdenture. This duplicate serves 3 different functions. It can be used as a radiographic guide, surgical template, and custom tray adapted to the patient's occlusion. Advantages of the technique described are twofold: it is cost effective and makes use of equipment and materials commonly found in dental practices. The use of a single guide allows the clinician to refer to the recorded prosthetic data at each step of implant treatment.

Flapless implant surgery in the edentulous jaw based on three fixed intraoral reference points and image-guided surgical templates: accuracy in human cadavers

OBJECTIVES

In edentulous patients, accurate and stable positioning of a surgical template is impeded by the mobile mucosal tissue. The objective was to evaluate the accuracy of flapless computer-assisted template-guided surgery in an edentulous human cadaver specimen using three fixed oral reference points (FRP) for fixation of the registration mouthpiece and the consecutive surgical template.

MATERIAL AND METHODS

Oral implants were planned on the computed tomography (CT) of an edentulous human cadaver specimen. Surgical templates have been fabricated using a multipurpose navigation system. Both the registration mouthpiece and consecutive surgical template were supported via three FRP. Study implants were inserted through the guide sleeves and the accuracy was evaluated on a post-surgical CT of the cadaver jaws fused with the pre-surgical planning CT. A Matlab script enabled comparison of the planned surgical path with the study implants.

RESULTS

In five maxillary and three mandibular edentulous human cadaver specimens, a total of 51 implants (35 implants in the maxilla and 16 implants in the mandible) have been placed. The mean+/-standard deviation total error (Euclidean distance)/lateral error (normal deviation) were 1.1+/-0.6/0.7+/-0.5 mm at the implant base and 1.2+/-0.7/0.9+/-0.7 mm at the implant tip. The mean angular error was 2.8+/-2.2 degrees.

CONCLUSIONS

Flapless surgery based on FRP-supported image-guided surgical templates may provide similar accuracy as reported for tooth-supported surgical templates or surgical navigation.

Computer-assisted surgery in the edentulous jaw based on 3 fixed intraoral reference points

PURPOSE

In computer-assisted implantation surgery, the transfer of prosthodontic-guided planning to the operative site is usually based on a registration template. The precise repositioning of the registration template is crucial for high accuracy and is compromised in edentulous jaws. The purpose was to determine the in vitro registration and targeting accuracy for surgical navigation in the edentulous jaw based on 3 fixed intraoral reference points.

MATERIALS AND METHODS

Edentulous maxilla and mandible cadaver specimens were provided with 3 fixed reference-point screws. A resin template with matrices for the fixed reference-point screws was produced and connected to a Vogele-Bale-Hohner registration mouthpiece and external registration frame with a snap-lock system. Surgical implants were planned on computed tomographic data and the corresponding dental stone casts were drilled under guidance of an optical navigation system. For evaluation of the registration accuracy, fiducial registration error was recorded and application accuracy was evaluated by fusion of postsurgical computed tomographic scans of the drilled dental stone casts with the presurgical planning computed tomogram.

RESULTS

In 9 maxillas and 5 mandibles, 14 registrations and 104 stone cast drillings were performed. The mean fiducial registration error was 0.49 +/- 0.14 mm (0.37 to 0.9 mm). The mean total error at the tip of the borehole was 0.88 +/- 0.65 mm (0.0 to 4.24 mm). The mean lateral errors were 0.51 +/- 0.49 mm (0.0 to 2.80 mm) at the base and 0.46 +/- 0.34 mm (0.0 to 1.5 mm) at the tip of the borehole, respectively. The mean angular error was 0.83 +/- 0.60 degrees (0.0 to 2.5 degrees ).

CONCLUSION

Three fixed intraoral reference points successfully support a registration mouthpiece and provide in vitro registration and targeting accuracy that is comparable to tooth-supported registration templates or bone marker registration.

Computer-Assisted Surgery in the Lower Jaw: Double Surgical Guide for Immediately Loaded Implants in Postextractive Sites—Technical Notes and a Case Report

Computer-assisted surgery is based on computerized tomography (CT) scan technology to plan the placement of dental implants and a computer-aided design/computer-aided manufacturing (CAD-CAM) technology to create a custom surgical template. It provides guidance for insertion implants after analysis of existing alveolar bone and planning of implant position, which can be immediately loaded, therefore achieving esthetic and functional results in a surgical stage. The absence of guidelines to treat dentulous areas is often due to a lack of computer-assisted surgery. The authors have attempted to use this surgical methodology to replace residual teeth with an immediate implantoprosthetic restoration. The aim of this case report is to show the possibility of treating a dentulous patient by applying a computer-assisted surgical protocol associated with the use of a double surgical template: one before extraction and a second one after extraction of selected teeth.

The management of an edentulous maxilla using a CAD/CAM-guided immediately loaded provisional implant prosthesis with screw-retained and cement-retained abutments: a clinical report

Functional rehabilitation of edentulous jaws using a CAD/CAM-guided implant protocol is commonly recommended as a definitive treatment modality. A patient with an edentulous maxilla received 7 endosseous implants using a CAD/CAM surgical template. A provisional maxillary acrylic resin fixed complete denture was connected immediately after implant placement using a combination of screw-retained and cement-retained abutments.

Mandibular fractures associated with endosteal implants

PURPOSE

The purpose of this study is to report four cases of mandibular fractures associated with endosteal implants and to discuss prevention and treatment of these types of fractures.

DISCUSSION

To evaluate whether the patient's anatomy allows insertion of implants, radiological exams that demonstrate the height and the labial-lingual width are needed. To reduce the potential fracture problem, the mandible can be restrengthened with bone grafting techniques. The treatment of a fracture in an atrophic mandible is always a challenge because of the diminished central blood supply, the depressed vitality of the bone, and the dependence on the periosteal blood supply. The basic principles in fracture treatment are reduction and immobilization of the fractured site for restoration of form and function.

CONCLUSIONS

If implants are placed in severe atrophic mandible, iatrogenic fracture of the mandible may occur during or after implant surgery because implant placement weakens the already-compromised mandible. A few millimeters of cortical bone should remain on both the labial and the lingual sites after the hole for insertion of an implant has been drilled. A 3-D surgical planning should be recommended at least in severe atrophic mandibles in order to prevent a severe reduction of bone tissue.

A prospective study on the accuracy of mucosally supported stereolithographic surgical guides in fully edentulous maxillae

BACKGROUND

Flapless implant placement using guided surgery is widespread, although clinical publications on the precision are lacking.

PURPOSE

The purpose of this study was to evaluate the accuracy of mucosal-supported stereolithographic guides in the edentulous maxillae.

MATERIALS AND METHODS

Seventy-eight OsseoSpeed™ implants (Astra Tech AB, Mölndal, Sweden) of 3.5 to 5 mm width and 8 to 15 mm length were installed consecutively in 13 patients. Implants were functionally loaded on the day of surgery, and implant location was assessed with a computed tomography scan. Mimics 9.0 software (Materialise N.V., Leuven, Belgium) was used to fuse the images of the virtually planned and actually placed implants, and the locations, axes, and interimplant distances were compared.

RESULTS

One implant was lost shortly after insertion because of abscess formation caused by remnants of impression material. Seventy-seven implant locations were analyzed. The deviation at the entrance point ranged between 0.29 mm and 2.45 mm (SD: 0.44 mm), with a mean of 0.91 mm. Average angle deviation was 2.60° (range 0.16-8.86°; SD: 1.61°). At the apical point, the deviation ranged between 0.32 mm and 3.01 mm, with a mean of 1.13 mm (SD: 0.52 mm). The mean deviation of the coronal and apical interimplant distance was respectively 0.18 mm (range 0.07-0.32 mm; SD: 0.15) and 0.33 mm (range 0.12-0.69 mm; SD: 0.28). These deviations are lower than the global coronal and apical deviations.

CONCLUSION

The present study is the first to investigate the accuracy of stereolithographic, full, mucosally supported surgical guides in the treatment of fully edentulous maxillae. Clinicians should be warned that angular and linear deviations are to be expected. Short implants show significantly lower apical deviations compared with longer ones. Reasons for implant deviations are multifactorial; however, it is unlikely that the production process of the guide has a major impact on the total accuracy of a mucosal-supported stereolithographic guide.

A systematic review on the accuracy and the clinical outcome of computer-guided template-based implant dentistry

INTRODUCTION

The aim of this systematic review was to analyze the dental literature regarding accuracy and clinical application in computer-guided template-based implant dentistry.

MATERIALS AND METHODS

An electronic literature search complemented by manual searching was performed to gather data on accuracy and surgical, biological and prosthetic complications in connection with computer-guided implant treatment. For the assessment of accuracy meta-regression analysis was performed. Complication rates are descriptively summarized.

RESULTS

From 3120 titles after the literature search, eight articles met the inclusion criteria regarding accuracy and 10 regarding the clinical performance. Meta-regression analysis revealed a mean deviation at the entry point of 1.07 mm (95% CI: 0.76-1.22 mm) and at the apex of 1.63 mm (95% CI: 1.26-2 mm). No significant differences between the studies were found regarding method of template production or template support and stabilization. Early surgical complications occurred in 9.1%, early prosthetic complications in 18.8% and late prosthetic complications in 12% of the cases. Implant survival rates of 91-100% after an observation time of 12-60 months are reported in six clinical studies with 537 implants mainly restored immediately after flapless implantation procedures.

CONCLUSION

Computer-guided template-based implant placement showed high implant survival rates ranging from 91% to 100%. However, a considerable number of technique-related perioperative complications were observed. Preclinical and clinical studies indicated a reasonable mean accuracy with relatively high maximum deviations. Future research should be directed to increase the number of clinical studies with longer observation periods and to improve the systems in terms of perioperative handling, accuracy and prosthetic complications.

Computer-aided design/computer-aided manufacturing applications using CT and cone beam CT scanning technology

CT and cone-beam CT technology provides clinicians with new methods to view patient anatomy exceeding conventional two-dimensional radiology. Interactive software applications allow for improved interpretation of the CT scan data. Proper use of this new technology must be based on a solid foundation of fundamental surgical and prosthodontic protocols. Advances in software and associated hardware have empowered clinicians with the necessary tools to harness the technology, while remaining true to conventional standards. The enhanced capability of innovative software applications that allow clinicians to interpret and maneuver through various three-dimensional images has far-reaching implications when interactive treatment planning software is combined with computer-aided design and manufacturing. Using all available virtual tools, true restoratively driven implant dentistry can be accomplished, ultimately benefiting patients.

Treatment outcome of immediately loaded implants installed in edentulous jaws following computer-assisted virtual treatment planning and flapless surgery

OBJECTIVES

The objective was to evaluate the outcome of immediately loaded implants installed in edentulous jaws following computer-assisted virtual treatment planning combined with flapless surgery.

MATERIAL AND METHODS

Twenty-nine edentulous patients (9 females, 20 males, mean age of 71.5 years) were treated using the Nobel Guide protocol for surgical planning, fixture installation and immediate functioning of a prefabricated fixed implant prosthesis. One hundred and seventy-six fixtures were installed to support 21 maxillary and 10 mandibular reconstructions. Patients were followed for up to 44 months.

RESULTS

Nineteen out of 176 fixtures were lost between 2 and 18 months after installation. Fixture survival rate was 89% (92% maxilla, 83% mandible). Implant-supported suprastructures remained stable during the follow-up period in 26 out of 31 jaws (90% maxilla, 70% mandible). Surgical or technical complications occurred in 42% of treated cases. Misfit of abutment-bridge appeared in five cases, resulting in disconnection of the bridge in two patients where fixtures were left for unloaded healing. Fixture losses resulted in the removal of the suprastructure in three patients, who returned to removable dentures. Extensive adjustments of occlusion were made in 10% of the immediately connected bridges. Radiographic bone defects developed in three patients after drilling, which appeared in two cases after anchor-pin drilling in the maxilla and another in a severely resorbed mandible.

CONCLUSION

The patient's post-operative discomfort such as swelling and pain was almost negligible. However, compared to conventional protocols, the occurrences of surgical and technical complications were higher, and thus this method must still be regarded to be in an exploratory phase.

The management of a completely edentulous patient using simultaneous maxillary and mandibular CAD/CAM-guided immediately loaded definitive implant-supported prostheses: a clinical report

Functional rehabilitation of a completely edentulous patient with removable prostheses is a clinical challenge. A patient with an edentulous maxilla and mandible received 6 endosseous implants in the maxilla and 5 implants in the mandible using CAD/CAM surgical templates. Definitive maxillary and mandibular implant-supported fixed complete dentures were connected immediately after implant placement using a CAD/CAM-guided implant surgical placement protocol.

The management of a severely resorbed edentulous maxilla using a bone graft and a CAD/CAM-guided immediately loaded definitive implant prosthesis: a clinical report

Functional reconstruction of an occlusion with severe residual ridge resorption is a clinical challenge. Removable prostheses are unsuccessful in situations with severe bone resorption. A patient with an edentulous maxilla received bone grafts from the anterior iliac crest to augment the maxillary alveolar residual ridges. The maxilla underwent bilateral sinus lift in the posterior area and onlay bone graft on the anterior maxilla using platelet-rich plasma. Eight endosseous implants were placed using a CAD/CAM surgical template approximately 6 months after the bone augmentation procedure. A prefabricated definitive implant-supported fixed complete denture was connected immediately after implant placement using a CAD/CAM-guided surgical implant placement protocol.