Comparative Analysis of Sensory Responses from Dental Implants vs Natural Teeth: An In Vivo Study.

To compare subjects' sensory responses to horizontal and vertical forces on tooth- and implant-supported restorations. In this prospective study, three protocols simulating the horizontal or vertical forces that occur during mastication were used to obtain subjective responses from subjects. These protocols included the measurement of horizontal force intensity during excursive movements and the identification of initial contact during guided and free vertical closure.

Strains in the implant collars supporting a cantilevered cross-arch bar prosthesis. An in vitro study.

Purpose: To examine the strains in the collar area of implants supporting a cantilevered cross-arch bar prosthesis during vertical load application.

Materials And Methods: A milled cross-arch metal framework supported by four implants in a trapezoidal design was supported in polymethylmethacrylate. T-strain gage rosettes were attached to the crestal areas of the implants with two grids, one recording circumference strain of the crestal area of the implant and the second recording vertical strain, torquing strains of the implant.

Fracture Strength of Implant Screw-Retained All-Ceramic Crowns with the Use of the Angulated Screw Channel: A Pilot Study.

To correct for angulation discrepancies in the maxilla, implant companies have designed angulated screw channel (ASC) abutments. The design of these abutments allows for the restorative screw channel to be placed up to 25 degrees off the center axis of the implant. Minimal independent research has been published to evaluate the fatigue resistance of this implant-abutment connection.

Efficacy of Several Retightening Protocols for Maintaining Clamping Force in the Implant-Abutment Joint: An In Vitro Pilot Study.

Purpose: Stability of an implant-supported restoration is an ultimate measure of the success of the procedure. It has been recommended by some to retighten the abutment screw for maintenance of the crown on the implant. The purpose of this study was to evaluate the usefulness of two retightening protocols to maintain the clamping force.

Retentive strength and marginal discrepancies of a ceramic-reinforced calcium phosphate luting agent: An in vitro pilot study.

Statement Of Problem: Information on the properties of a relatively new luting agent with a unique formulation (ceramic-reinforced calcium phosphate) is limited.

Purpose: The purpose of this in vitro study was to compare the retentive strengths and marginal discrepancies of a ceramic-reinforced calcium phosphate luting agent (CM) with a self-adhesive resin luting agent (RX) and to determine and compare the mode of failure of dislodged cemented copings.

Material And Methods: Forty extracted human molar teeth were prepared to receive zirconia copings.

The effects of loading on the preload and dimensions of the abutment screw for a 3-unit cantilever-fixed prosthesis design.

Objective: The purpose of this study was to use an in vitro model system to compare the effects on the screw torque and screw dimensions within 2 commercially available implant systems from occlusal loading on a cantilevered-fixed partial denture.

Materials And Methods: Cantilevered implant-supported 3-unit prostheses with 2 premolar abutments and 1 premolar pontic (7.3 mm in length) were made on resin casts containing 2 implant analogs for 2 implant systems: BioLok Silhouette Tapered Implant System (Birmingham, AL) and Zimmer Tapered Screw-Vent Implant System (Carlsbad, CA) with 10 samples in each group.

Analysis of dimensional changes in the screw and the surface topography at the interface of a titanium screw and a zirconia abutment under cyclic loading: an in vitro study.

Purpose: The purpose of this experiment was to analyze the mechanics of the ceramic abutment-implant joint and the dimensional changes in the abutment screws from cyclic loading.

Materials And Methods: Two groups of experimental assemblies were used, one with zirconia abutments and the other with titanium abutments (n = 10). Each specimen consisted of an implant, an abutment, and a metal crown affixed in an acrylic resin base.

Sensory discrimination of teeth and implant-supported restorations.

Purpose: The purpose of this study was to examine patient responses to load application on natural teeth and implants using a visual analog scale (VAS).

Materials And Methods: Ten subjects were selected from the University of Medicine and Dentistry of New Jersey patient pool who had a single implant-supported crown restoration adjacent to a natural tooth. Vibrational loads of 0.

Changes in abutment screw dimensions after off-axis loading of implant-supported crowns: a pilot study.

Introduction: Loss of screw tightness resulting in abutment movement and displacement of the crown or prosthesis may occur from plastic deformation of the screw. This study correlates changes in screw length and diameter with previously reported loss of screw tightness.

Materials And Methods: Samples consisting of a 4 × 10-mm implant (potted in polymethylmethacrylate resin), a standard abutment, and the cemented crown were loaded with a 200-N force for 1 × 10 cycles.

An in vitro analysis of implant screw torque loss with external hex and internal connection implant systems.

Purpose: The purpose of this study was to examine, in a controlled environment, effects of connection design upon screw stability. Implant fixtures have 2 types of connections to the abutment: internal connection and external hex. Four implant systems were tested: Bio-Lok (external hex; Bio-Lok International, Inc.

Analysis of changes in implant screws subject to occlusal loading: a preliminary analysis.

Loosening of the abutment screw can present a problem for the stability of the implant-supported crown or prosthesis. The purpose of this study was to understand the parameters of screw loosening, using an in vitro model, including loss of torque, screw head rotation, changes in screw dimension, and distortion of the implant-abutment joint. Implants (4 x 10 mm) were potted in autopolymerizing blocks.