Clinical performance of provisional screw‐retained metal‐free acrylic restorations in an immediate loading implant protocol: a 242 consecutive patients' report

Objective: To evaluate the clinical performance of provisional screw‐retained metal‐free acrylic restorations in an immediate loading implant protocol. Material and methods: Two hundred and forty‐two consecutive patients were selected retrospectively, who received 1011 implants and 311 immediate provisional screw‐retained implant restorations (2–4 h after implant surgery). The patients were monitored for a period of 2–3 months, until they were referred for a final restoration. The primary variables recorded include the survival time and the appearance of fractures in the provisional restoration, and the independent variables included age, sex, dental arch, type of restoration, type of attachment and components used, as well as cantilevers and opposing dentition. A survival analysis (Kaplan–Meier) and a Cox regression analysis were performed. Results: Twenty‐three restorations in 20 patients (8.26%, 95% CI 4.8–11.7) showed at least one fracture (7.39%). More than half of the new fractures (52%, 12 cases) occurred in the first 4 weeks. The cumulative survival probability observed was greater in mandible (P=0.05) and non‐cantilever restorations (P=0.001), and in those opposed by full restorations or natural teeth (P=0.001). With an opposing implant‐supported prosthesis, the risk of fracture was multiplied by 4.7, and the use of cantilevers as well as the location of the restoration in the maxilla multiply the risk by 3.4–3.5. Conclusions: Immediate provisional screw‐retained metal‐free implant‐supported restorations can be considered a reliable restoration (92.6% remain intact) for the healing period of 3 months. To cite this article:
Suarez‐Feito JM, Sicilia A, Angulo J, Banerji S, Cuesta I, Millar B. Clinical performance of provisional screw‐retained metal‐free acrylic restorations in an immediate loading implant protocol: a 242 consecutive patients' report.
Clin. Oral Impl. Res. 21 , 2010; 1360–1369.
doi: 10.1111/j.1600‐0501.2010.01956.x     

Complete Arch Monolithic Zirconia Prosthesis Supported By Cobalt Chromium Metal Bar: A Clinical Report

Complete arch fixed implant supported prosthesis made of monolithic zirconia is a popular treatment option with minimal complications, as documented in the literature over a 5‐year period. One of the limitations of this material is its inability to be used when the span between adjacent implants is excessively long. A potential solution to mitigate this problem is to support the zirconia prosthesis with a metal substructure, which intrinsically has higher tensile strength. This clinical report describes the successful use of this prosthetic design in a male patient with bruxism and history of multiple implant failures in the maxilla. This resulted in a large anterior‐posterior span between the anterior implants in the maxillary lateral incisor region and the distal implants in the pterygoid region. This article also describes the use of a split file digital workflow to scan the prototype prosthesis and then digitally design and mill the screw‐retained cobalt chromium bar, as well as the overlaying of zirconia prosthesis which was retained by separate screws. This novel approach offers promise for management of the atrophic maxilla where implants with remote anchorage are used resulting in broader distribution of implants.     

Individual Lithium Disilicate Crowns in a Full‐Arch,Implant‐Supported Rehabilitation: A Clinical Report

This clinical report presents the clinical outcome of a maxillary full‐arch implant‐supported fixed rehabilitation with lithium disilicate reinforced glass ceramic monolithic crowns opposing a mandibular metal‐acrylic implant‐supported fixed rehabilitation in a 62‐year‐old woman. Eight implants were successfully placed (four maxillary, four mandibular), and no complications occurred in the postoperative or maintenance periods. Six months after delivery, the maxillary and mandibular prostheses were found to be clinically, biologically, and mechanically stable, and the patient was satisfied with the esthetics and her ability to function. Although the present indications for the use of lithium disilicate are still restricted to tooth‐borne restorations, it is possible to successfully rehabilitate edentulous patients through implant‐supported fixed prostheses using lithium disilicate reinforced glass ceramic monolithic crowns.     

Fabrication of an Implant‐Supported Fixed Interim Prosthesis Using a Duplicate Denture: An Alternative Technique

The fabrication of an implant‐supported fixed complete denture prosthesis involves multiple clinical and laboratory steps. One of the main steps is to provide the patient with an interim fixed prosthesis to evaluate the patient's esthetic and functional needs as well as to enhance the patient's psychology before proceeding to the definitive prosthesis. Different techniques for fabricating interim prostheses have been described in the literature. This report describes an alternative technique that uses a duplicate denture made of self‐curing acrylic resin to fabricate an implant‐supported fixed interim prosthesis. The interim prosthesis was later used as a blueprint for the definitive implant‐supported hybrid prosthesis.     

The implant-supported milled-bar mandibular overdenture

Osseointegrated dental implants have been proven successful in the treatment of edentulism. The predictability of the implant‐supported prosthesis has also been established. Several techniques have been described for the successful restoration of the edentulous mandible: fixed‐detachable prostheses with either the original Brånemark hybrid prosthesis design or conventional implant‐supported fixed partial dentures, implant‐retained overdentures, and implant‐supported overdentures. However, in cases of advanced ridge resorption in which facial tissue support is needed from the flanges of the prosthesis or when a removable type of prosthesis is preferred by the patient, an implant‐supported prosthesis is indicated. Electric discharge machining is often used in the fabrication of the bar for an implant‐supported overdenture. This procedure is very costly and technique sensitive. An alternative procedure to fabricate a milled‐bar implant‐supported overdenture is described. This procedure is simple and uses inexpensive equipment and materials. The milled‐bar minimizes lateral and rotational displacement. The overdenture incorporates attachments that provide retention, minimizing possible movement along the path of insertion. This type of prosthesis is available to a broad patient population, especially those with advanced ridge resorption, providing an excellent result at a reduced cost.     

Alternative method to fabricating an immediately loaded mandibular hybrid prosthesis without impressions: a clinical report

Immediate loading procedures may cause discomfort to the patient and increase the possibility of damage to the surgical site during prosthetic restorations. The aim of this clinical report is to describe an alternative method to fabricating a mandibular hybrid prosthesis in 3 days without taking an impression. Five implants were placed in the anterior region of an edentulous mandible and restored with a definitive mandibular hybrid prosthesis using a unique acrylic resin framework. This acrylic resin framework enabled the fabrication of the metal framework of the mandibular hybrid prosthesis without taking a final impression. The step-by-step technique is described.     

Management of a Fractured Multiunit Maxillary Implant‐Supported Fixed Prosthesis with Stripped Abutment Screws Using a Hybrid Cement‐Retained and Screw‐Retained Design: A 5‐Year Follow‐Up Clinical Report

Fracture and loosening of implant‐supported prostheses (ISPs) are complications encountered in routine dental practice. In the present report, management of a fractured maxillary full‐arch cement‐retained (CR) fixed dental prosthesis supported by six implants is presented. Due to stripped screws, complications were encountered that prevented the retrieval of two of the six abutment screws, which was managed by using a hybrid retention approach, whereby a single full‐arch CR and screw‐retained (SR) ISP was used. The techniques used to successfully retrieve four of the abutment screws are described. The final retention design involved a combination of three CR and three SR restorations, which offers the advantages of both retention designs.     

Impact of implant number,distribution and prosthesis material on loading on implants supporting fixed prostheses

Summary  The purpose of this study is to evaluate axial forces and bending moments (BMs) on implants supporting a complete arch fixed implant supported prosthesis with respect to number and distribution of the implants and type of prosthesis material. Seven oral Brånemark implants with a diameter of 3.75 mm and a length of 13 and 7 mm (short distal implant) were placed in an edentulous composite mandible used as the experimental model. One all‐acrylic, one fibre‐reinforced acrylic, and one milled titanium framework prosthesis were made. A 50 N vertical load was applied on the extension 10 mm distal from the most posterior implant. Axial forces and BMs were measured by calculating signals from three strain gauges attached to each of the abutments. The load was measured using three different models with varying numbers of supporting implants (3, 4 and 5), three models with different implant distribution conditions (small, medium and large) and three models with different prosthesis materials (titanium, acrylic and fibre‐reinforced acrylic). Maximum BMs were highest when prostheses were supported by three implants compared to four and five implants (P < 0.001). The BMs were significantly influenced by the implant distribution, in that the smallest distribution induced the highest BMs (P < 0.001). Maximum BMs were lowest with the titanium prosthesis (P < 0.01). The resultant forces on implants were significantly associated with the implant number and distribution and the prosthesis material.     

A Simplified Technique for Creating a Customized Gingival Emergence Profile for Implant‐Supported Crowns

A successful implant restoration is one that will allow adequate function and esthetics. Soft‐tissue management around implant‐supported restorations continues to present a considerable challenge for the restoring dentist as well as the laboratory technician while fabricating the final prosthesis. This article presents a simplified and economical technique to direct gingival tissue healing, as well as create a removable gingival replica of the customized gingival emergence profile. The created profile can then be used in the dental laboratory to achieve a superior and predictable esthetic outcome for implant‐supported fixed restorations.     

Zirconia in fixed implant prosthodontics

Background: CAD/CAM technology in combination with zirconia ceramic has increasingly gained popularity in implant dentistry. Purpose: This narrative review presents the current knowledge on zirconia utilized as framework material for implant‐borne restorations and implant abutments, laboratory tests and developments, clinical performance, and possible future trends for implant dentistry are addressed. Material and Methods: A review of available literature from 1990 through 2010 was conducted with search terms zirconia,”“implants,”“abutment,”“crown,” and “fixed dental prosthesis” using electronic databases (PubMed) and manual searching. Results: Latest applications of zirconia in implant dentistry include implant abutments, multiple unit and full‐arch frameworks as well as custom‐made bars to support fixed and removable prostheses. High biocompatibility, low bacterial surface adhesion as well as favorable chemical properties of zirconia ceramics are reported. Zirconia stabilized with yttrium oxide exhibits high flexural strength and fracture toughness due to a transformation toughening mechanism. Preliminary clinical data confirmed the high stability of zirconia for abutments and as a framework material for implant borne crowns and fixed dental prostheses. Zirconia abutment or framework damage has rarely been encountered. However, veneering porcelain fractures are the most common technical complication in implant‐supported zirconia restorations. These porcelain veneer failures have led to concerns regarding differences in coefficient of thermal expansions between core and veneering porcelain and their respective processing techniques. Conclusion: As presently evidence of clinical long‐term data is missing, caution with regard to especially extensive implant‐borne zirconia frameworks is recommended.     

Simplified Technique for Incorporating a Metal Mesh into Record Bases for Mandibular Implant Overdentures

Mandibular implant‐retained overdentures have become the standard of care for patients with mandibular complete edentulism. As part of the treatment, the mandibular implant‐retained overdenture may require a metal mesh framework to be incorporated to strengthen the denture and avoid fracture of the prosthesis. Integrating the metal mesh framework as part of the acrylic record base and wax occlusion rim before the jaw relation procedure will avoid the distortion of the record base and will minimize the chances of processing errors. A simplified method to incorporate the mesh into the record base and occlusion rim is presented in this technique article.     

An Alternative Technique for the Fabrication of a Metal‐Reinforced Interim Implant‐Supported Fixed Prosthesis: A Clinical Report

Despite advancements in restorative materials and techniques, complications with implant‐supported fixed prostheses such as veneer fracture and material wear are very common and present with varying frequencies. Following these complications, repair of this type of prosthesis can be time‐consuming and costly even in the hand of experience clinicians. Several techniques have proposed using the existing framework to minimize the cost of the repair for the patient; however, while the repairs are being performed, the patient will have to either wear an interim complete denture or no prosthesis, which might cause some inconvenience to the patient. This article will present a technique for the fabrication of a metal‐reinforced interim implant‐supported fixed prosthesis for patients to wear while the existing prosthesis is being repaired.     

The transmandibular implant: prosthodontic treatment considerations.

The transmandibular implant (TMI) is a type of transosteal implant designed for use in the edentulous mandible. The implant is composed of a gold-based alloy. The TMI is a loaded implant in that the prosthesis is supported by the implant. A transitional type of prosthesis, for insertion following surgery can be made either by altering the patient's existing mandibular complete denture or by making a new denture. The completed prosthesis is retained by clips held in the mandibular denture with autopolymerizing acrylic resin. The clips engage Dolder bar segments, which are a part of the implant suprastructure, and provide the necessary retention for the mandibular complete denture.     

Workflow for a metal-resin-zirconia fixed complete denture: A dental technique

The hard- and soft-tissue replacement materials in the traditional workflow for an implant fixed complete denture are acrylic resin and conventional resin denture teeth supported by a rigid substructure. A novel technique is described combining a modified digital complete denture workflow with analog components and systems, allowing the use of multicolored zirconia and 3D-printed resin. In combination with an appropriate metal substructure, a high-quality prosthesis can be fabricated with reduced effort and cost.     

A 30‐Year Follow‐Up of a Patient with Mandibular Complete‐Arch Fixed Implant‐Supported Prosthesis on 4 Implants: A Clinical Report

Mandibular complete‐arch fixed implant‐supported prostheses are recognized as one of the earliest and most popular prostheses in implant dentistry. This prosthesis was the main focus in the early era of osseointegration. Despite its widespread popularity, few clinical reports have described long‐term follow‐up greater than 10 years for this type of prosthesis. This report describes a 30‐year follow‐up of a patient who underwent treatment for a mandibular complete‐arch fixed implant‐supported prosthesis with 4 machined surfaced implants, opposing a maxillary complete denture. This report documents a variety of photographs and radiographs taken over a period of 30 years to compare bone levels at various stages of care and maintenance, including de novo bone formation underneath the distal cantilevers due to functional loading. The biologic and biomechanical response to this treatment protocol and long‐term clinical observations and prosthodontic outcome and maintenance needs are also addressed.     

Syncrystallization: a technique for temporization of immediately loaded implants with metal-reinforced acrylic resin restorations

Background Rigid temporization has been recognized to have a significant impact on the peri‐implant tissue response in immediate implant loading since it reduces the mechanical stress exerted on each implant. Purpose A successful protocol for immediate loading of multiple implants depends on an adequate fixation and immobility of the implants to prevent the risk of micromovements in relation to the surrounding bone. The objective of this article was to evaluate a prosthetic concept for an accelerated rigid splinting of multiple implants for same‐day immediate loading with metal‐reinforced provisional restorations using a technique of welding temporary implant abutments with a prefabricated titanium bar directly in the oral cavity (syncrystallization). Materials and Methods Between June 2004 and January 2005, immediate loading of threaded implants with a metal‐ reinforced acrylic resin provisional restoration at stage 1 surgery was evaluated in 40 consecutive patients. A total of 192 implants were placed in selected edentulous or partially edentulous patients using the syncrystallization technique. Once the titanium bar was welded intraorally to the abutments, opaque was applied and the provisional restoration was relined and screw‐retained the same day. In addition, a comparison of deformations and stress distributions in implant‐supported, metal‐reinforced and nonmetal‐reinforced resin provisional restorations was analyzed in the edentulous mandible by a three‐dimensional finite element model (FEM). Results All of the 192 rigidly temporized immediately loaded implants osseointegrated. An implant success rate of 100% was achieved over a period of 6 months postplacement. No fracture or luting cement failure of the provisional restoration occurred during the observation time. Compared to mere acrylic superstructures, a significant reduction of deformation and strain within metal‐reinforced provisional restorations was detected by FEM analysis. Conclusion The results of this study indicate that the syncrystallization technique allows an expedite and adequate rigid splinting of multiple immediately loaded implants. The advantages of the technique are: (1) reduction of treatment time for immediate temporization at stage 1 surgery; (2) predictable fixation and immobility of implants in the early stages of bone healing; and (3) less time for repairing provisional restorations as a result of no or rare fracture.     

A multifunctional, provisional, implant-retained fixed partial denture

This article describes the modification of a procedure for fabricating a laboratory-processed, metal-reinforced, acrylic resin provisional restoration that becomes an implant-retained fixed partial denture. The modification involves the incorporation of patrix and matrix components into a cast metal framework. The prosthesis can be used as an alternative to a removable radiologic stent and surgical guide. It can function as a surgical guide during implant placement and help retract the buccal mucogingival flap during implant placement. The prosthesis also can be used as an aid in locating the implant during stage II surgery. Finally, the pontics can be converted into an implant-supported provisional restoration immediately after the implant prosthetic components are attached to the uncovered implants.     

Concepts for designing and fabricating metal implant frameworks for hybrid implant prostheses

Edentulous patients have reported difficulties in managing complete dentures; they have also reported functional concerns and higher expectations regarding complete dentures than the dentists who have treated them. Some of the objectives of definitive fixed implant prosthodontic care include predictable, long-term prostheses, improved function, and maintenance of alveolar bone. One of the keys to long-term clinical success is the design and fabrication of metal frameworks that support implant prostheses. Multiple, diverse methods have been reported regarding framework design in implant prosthodontics. Original designs were developed empirically, without the benefit of laboratory testing. Prosthetic complications reported after occlusal loading included screw loosening, screw fracture, prosthesis fracture, crestal bone loss around implants, and implant loss. Numerous authors promoted accurately fitting frameworks; however, it has been noted that metal frameworks do not fit accurately. Passively fitting metal implant frameworks and implants have not been realized. Biologic consequences of ill-fitting frameworks were not well understood. Basic engineering principles were then incorporated into implant framework designs; however, laboratory testing was lacking. It has been reported that I- and L-beam designs were the best clinical option. With the advent of CAD/CAM protocols, milled titanium frameworks became quite popular in implant prosthodontics. The purpose of this article is to discuss current and past literature regarding implant-retained frameworks for full-arch, hybrid restorations. Benefits, limitations, and complications associated with this type of prosthesis will be reviewed. This discussion will include the relative inaccuracy of casting/implant fit and improved accuracy noted with CAD/CAM framework/implant fit; cantilever extensions relative to the A/P implant spread; and mechanical properties associated with implant frameworks including I- and L-beam designs. Guidelines will be proposed for use by clinicians and laboratory technicians in designing implant-retained frameworks.     

The clinical success of tooth‐ and implant‐supported zirconia‐based fixed dental prostheses. A systematic review

The aim was to make an inventory of the current literature on the clinical performance of tooth‐ or implant‐supported zirconia‐based FDPs and analyse and discuss any complications. Electronic databases, PubMed.gov, Cochrane Library and Science Direct, were searched for original studies reporting on the clinical performance of tooth‐ or implant‐supported zirconia‐based FDPs. The electronic search was complemented by manual searches of the bibliographies of all retrieved full‐text articles and reviews, as well as a hand search of the following journals: International Journal of Prosthodontics, Journal of Oral Rehabilitation, International Journal of Oral & Maxillofacial Implants and Clinical Oral Implants Research. The search yielded 4253 titles. Sixty‐eight potentially relevant full‐text articles were retrieved. After applying pre‐established criteria, 27 studies were included. Twenty‐three studies reported on tooth‐supported and 4 on implant‐supported FDPs. Five of the studies were randomised, comparing Y‐TZP‐based restorations with metal–ceramic or other all‐ceramic restorations. Most tooth‐supported FDPs were FDPs of 3–5 units, whereas most implant‐supported FDPs were full arch. The majority of the studies reported on 3‐ to 5‐year follow‐up. Life table analysis revealed cumulative 5‐year survival rates of 93·5% for tooth‐supported and 100% for implant‐supported FDPs. For tooth‐supported FDPs, the most common reasons for failure were veneering material fractures, framework fractures and caries. Cumulative 5‐year complication rates were 27·6% and 30·5% for tooth‐ and implant‐supported FDPs, respectively. The most common complications were veneering material fractures for tooth‐ as well as implant‐supported FDPs. Loss of retention occurred more frequently in FDPs luted with zinc phosphate or glass–ionomer cement compared to those luted with resin cements. The results suggest that the 5‐year survival rate is excellent for implant‐supported zirconia‐based FDPs, despite the incidence of complications, and acceptable for tooth‐supported zirconia‐based FDPs. These results are, however, based on a relatively small number of studies, especially for the implant‐supported FDPs. The vast majority of the studies are not controlled clinical trials and have limited follow‐up. Thus, interpretation of the results should be made with caution. Well‐designed studies with large patient groups and long follow‐up times are needed before general recommendations for the use of zirconia‐based restorations can be provided.