Newsletter

The dental prostheses offered to edentulous and partially edentulous patients often reflect personal preferences rather than diagnostic factors that can lead to improved quality of life. Conventional vs implant-assisted and fixed vs removable prosthodontic therapies present advantages and disadvantages that vary broadly based on a patient’s preexisting conditions. Evidence-based decision-making is key to successful, durable and appropriate prosthodontic treatment planning for these patients. This issue of Prosthodontics Newsletter focuses on prosthodontics treatment related to our patients’ ongoing quality of life.

Using 2 anteriorly positioned dental implants to support, retain and stabilize an overdenture is a desirable, perhaps even the preferred, method to restore the edentulous mandible. Indeed, improving the diminishing prosthodontic foundation with implants facilitates mastication, phonation, esthetics, comfort and overall quality of life. Mechanical retention of these prostheses can be improved by various commercially available and laboratory-manufactured attachment systems, generally categorized as either “stud” or “bar” attachments. This issue of Prosthodontics Newsletter looks at clinical studies that compare various attachment systems to determine if any one attachment system is superior to the rest.

Management of edentulous patients with implant restorations can have a dramatic impact on the esthetic appearance of the dentofacial complex. Failure to visualize the intended result during diagnosis often renders definitive restorations inadequate structurally, functionally and esthetically. Appreciating factors that influence the esthetics of full-arch implant-supported restorations will permit their diagnostic consideration before therapy onset rather than after prosthesis placement, when it may be too late to make needed changes. In this issue of Prosthodontics Newsletter, we present a few esthetic considerations affecting the outcomes of these complicated restorations.

Although single-tooth implants have excellent survival rates, their survival is frequently accompanied by a loss of peri-implant marginal bone. Immediate implantation accompanied by restoration in the extraction socket may reduce soft and hard tissue recession of the alveolar ridge, thereby minimizing initial bone remodeling. While depth of bone support and peri-implant soft tissue are key factors in the health and function of implants, integrating peri-implant soft tissue is essential for restorations in the esthetic zone.

The clinical performance of dental implant restorations may be influenced by many factors, not the least of which is the fit/adaptation between the prosthesis and the supporting implants. In turn, implant prosthesis fit may be influenced by impression and scanning accuracy, prosthesis design, components used, a wide variety of manufacturing elements, clinical placement of the definitive restoration and subsequent prosthesis maintenance. While reams of literature have been published on the topic of implant restoration fit, this issue of the Prosthodontics Newsletter will review select studies of a few critical considerations that will help practitioners improve the delivery of care.

Central to reliable dental implant restoration is the dentist’s capacity to understand and appropriately manage prosthesis retention screws. In this respect, dentists have truly become modern-day oral engineers. Predictable therapeutic success requires an appreciation of screw-joint preload, screw-torque maintenance during function, and screw lubrication and its impact on preload, along with factors influencing the anticipated loss of preload over time and reliable mechanical generation of preload using the appropriate tools. In this issue of Prosthodontics Newsletter, we review some of the current literature detailing the application of prosthesis retention screws in successful implant dentistry.

In the past, labial implant projection in the anterior maxilla might have required prosthetic screw access through facial or incisal restoration surfaces. Introduction of the angled screw channel (ASC) concept permitted prosthetic screw tightening using a hexalobular, sphere-shaped driver that engages the screw at various angles. This allows the screwdriver and the restoration’s screw channel to follow an orientation different than the implant’s long axis to emerge more esthetically through the restoration’s palatal surface. While the ASC design may have solved the esthetic concern, other problems may arise. This issue of Prosthodontics Newsletter looks at recent research on the ASC.

The movement of teeth adjacent to dental implant restorations is a perplexing and complicated phenomenon that may relate to normal alveolar growth, functional occlusal loading or parafunctional occlusal activities, or it may have some multifactorial etiology. Although understanding the factors that may lead to adjacent tooth movement is important, the mere fact that it occurs is an essential consideration in treatment planning, restoration and maintenance protocols.

To provide optimal implant-based clinical care for partially edentulous patients missing 2 to 3 teeth, the practitioners must consider implant location and design of the restoration prior to implant surgery.

The relatively recent development of titanium base abutments for implant-supported fixed prosthodontics, particularly single implant restorations, was intended to solve key laboratory and clinical problems.