Stress distribution on implant- supported zirconia crown of maxillary first molar: effect of oblique load on natural and antagonist tooth.

This study evaluated the stress distribution on an implant-supported zirconia crown of a mandibular first molar subjected to oblique loading by occlusal contact with the natural maxillary first molar by using the 3D finite element method. Two virtual models were made to simulate the following situations: (1) occlusion between maxillary and mandibular natural first molars; (2) occlusion between zirconia implant-supported ceramic crown on a mandibular first molar and maxillary natural first molar. The models were designed virtually in a modeling program or CAD (Computer Aided Design) (Rhinoceros).

Influence of the dental implant number and load direction on stress distribution in a 3-unit implant-supported fixed dental prosthesis.

Background: The choice between 2 or 3 implants to support a 3-unit implant-supported fixed dental prosthesis (FDP) still generates doubt in clinical practice.

Objectives: The aim of this study was to evaluate stress distribution in 3-unit implant-supported FDPs according to the implant number and load direction.

Material And Methods: A numerical simulation was performed to analyze stress and strain according to the implant number (2 or 3) and load direction (axial or oblique).

Effect of Framework Type on the Biomechanical Behavior of Provisional Crowns: Strain Gauge and Finite Element Analyses.

The aim of this study was to evaluate the effects of different frameworks on the biomechanical behavior of implant-supported provisional single crowns to indicate or not the use of plastic framework as infrastructure. For finite element analysis, a hemi-jaw stone model was scanned and modeled with an external hexagon implant. A framework was screwed onto the implant and a crown was constructed over it.

Evaluation of peri-implant condition in periodontally compromised patients.

Aims: The aim of the study is to evaluate the profile of peri-implant tissues in periodontally compromised patients.

Settings And Design: - cross sectional study design.

Materials And Methods: Fifty-eight implants were evaluated, clinically and radiographically, installed in seven individuals treated by the same team of professionals, during the years 1997 and 2005 in a private dental clinic in Vitória, ES, Brazil; that time of data collection, all implants were at least 10 years of functional loading.

Comparative in vivo study of alloy titanium implants with two different surfaces: biomechanical and SEM analysis.

Objectives: The purpose of this study was to evaluate the biomechanical behavior of the interface formed between bone and implants with machined surfaces (MS) and those modified by AlO sandblasting and acid etching (SBAS).

Materials And Methods: Before surgery, topographic characterization was performed by SEM-EDX and by mean roughness measurements. Ten Albinus rabbits received randomly 20 Ti-6Al-4V implants on its right and left tibiae, with one implant placed in each tibia.

Preservation of Dental Sockets Filled with Composite Bovine Bone. A Single-Blind Randomized Clinical Trial.

The purpose of this study was to evaluate the preservation of alveolar dimensions in human fresh extraction sockets filled with a composite bovine bone graft by means of design of single-blind randomized clinical trial. Forty participants had monoradicular teeth extracted (one teeth in each participant), and after were randomly divided into 2 groups: individuals whose fresh sockets were filled with the composite heterologous bone graft (Biomaterial Group), or with blood clot (Control Group). After extraction, the fresh sockets were measured at their greatest mesiodistal (MD) and bucco-lingual/palatal (BL/P) distance.

Influence of different alcohol intake frequencies on alveolar bone loss in adult rats: A sem study.

Background: Alcohol intake is associated with oral diseases and bone changes including alveolar bone loss in humans and in experimental animals. The main aim of the present study is to assess the effect of long-term alcohol intake, at different frequencies, on periodontal bone loss (PBL) in adult rats.

Material And Methods: Thirty-six (36) rats were divided into 3 groups: Control (daily water intake, n=12), daily alcohol intake (20% ethanol, n=12), and social alcohol intake (20% ethanol twice a week, n=12).

Influence of different restorative materials on the stress distribution in dental implants.

Background: To assist clinicians in deciding the most suitable restorative materials to be used in the crowns and abutment in implant rehabilitation.

Material And Methods: For finite element analysis (FEA), a regular morse taper implant was created using a computer aided design software. The implant was inserted at the bone model with 3 mm of exposed threads.

The importance of correct implants positioning and masticatory load direction on a fixed prosthesis.

Background: Through the biomechanical study of dental implants, it is possible to understand the dissipation effects of masticatory loads in different situations and prevent the longevity of osseointegration. Aims: To evaluate the microstrains generated around external hexagon implants, using axial and non-axial loads in a fixed four-element prosthesis with straight implants and implants inclined at 17°.

Material And Methods: Three implants were modeled using CAD software following the manufacturer's measurements.

Strain Gauge Evaluation of Transfer Impression Techniques of Multiple Implant-Supported Prosthesis.

Purpose: This in vitro study assessed the accuracy of multiple implant-level impression techniques (open tray and closed tray) for the fabrication of 3-unit implant prostheses with strain gauge (SG) analysis.

Materials And Methods: A polyurethane master model was designed to simulate a clinical situation. Two rigid custom trays were fabricated for the model.

Validation of a Simplified Implant-Retained Cantilever Fixed Prosthesis.

Purpose: To evaluate the stress and strain generated in a fixed four-element prosthesis under the application of axial and nonaxial loads using a simplified implant-supported fixed prosthesis model.

Materials And Methods: A 3-dimensional model was constructed containing 3 implants with a conventional anatomical prosthesis (G1). The second model with the same implant system received the simplified prosthesis (G2).

Comparative Microstrain Study of Internal Hexagon and Plateau Design of Short Implants Under Vertical Loading.

Purpose: To quantify microstrain development during axial loading using strain gauge analysis for short implants, varying the type of fixture-abutment joint and thread design.

Materials And Methods: An internal hexagon implant (4 × 8 mm) and a plateau design implant (4 × 8 mm) were embedded on the center of 10 polyurethane blocks with dimensions of 190 × 30 × 12 mm. The respective abutments were screwed onto the implants.

Effect of Jig Design and Assessment of Stress Distribution in Testing Metal-Ceramic Adhesion.

Purpose: In testing adhesion using shear bond test, a combination of shear and tensile forces occur at the interface, resulting in complex stresses. The jig designs used for this kind of test show variations in published studies, complicating direct comparison between studies. This study evaluated the effect of different jig designs on metal-ceramic bond strength and assessed the stress distribution at the interface using finite element analysis (FEA).

Load-application devices: a comparative strain gauge analysis.

In view of the low loading values commonly employed in dentistry, a load-application device (LAD) was developed as option to the universal testing machine (UTM), using strain gauge analysis. The aim of this study was to develop a load-application device (LAD) and compare the LAD with the UTM apparatus under axial and non-axial loads. An external hexagonal implant was inserted into a polyurethane block and one EsthetiCone abutment was connected to the implant.

Microstrain around dental implants supporting fixed partial prostheses under axial and non-axial loading conditions, in vitro strain gauge analysis.

The current study used strain gauge analysis to perform an in vitro evaluation of the effect of axial and non-axial loading on implant-supported fixed partial prostheses, varying the implant placement configurations and the loading points. Three internal hexagon implants were embedded in the center of each polyurethane block with in-line and offset placements. Microunit abutments were connected to the implants using a torque of 20 N · cm, and plastic prosthetic cylinders were screwed onto the abutments, which received standard patterns cast in Co-Cr alloy (n = 10).

Axial loads on implant-supported partial fixed prostheses for external and internal hex connections and machined and plastic copings: strain gauge analysis.

The aim of this in vitro study was to use strain gauge (SG) analysis to compare the effects of the implant-abutment joint, the coping, and the location of load on strain distribution in the bone around implants supporting 3-unit fixed partial prostheses. Three external hexagon (EH) implants and 3 internal hexagon (IH) implants were inserted into 2 polyurethane blocks. Microunit abutments were screwed onto their respective implant groups.

Straight and offset implant placement under axial and nonaxial loads in implant-supported prostheses: strain gauge analysis.

Purpose: The aim of this in vitro study was to quantify strain development during axial and nonaxial loading using strain gauge analysis for three-element implant-supported FPDs, varying the arrangement of implants: straight line (L) and offset (O).

Materials And Methods: Three Morse taper implants arranged in a straight line and three implants arranged in an offset configuration were inserted into two polyurethane blocks. Microunit abutments were screwed onto the implants, applying a 20 Ncm torque.

Effect of axial loads on implant-supported partial fixed prostheses by strain gauge analysis.

Objectives: The present study used strain gauge analysis to perform an in vitro evaluation of the effect of axial loading on 3 elements of implant-supported partial fixed prostheses, varying the type of prosthetic cylinder and the loading points.

Material And Methods: Three internal hexagon implants were linearly embedded in a polyurethane block. Microunit abutments were connected to the implants applying a torque of 20 Ncm, and prefabricated Co-Cr cylinders and plastic prosthetic cylinders were screwed onto the abutments, which received standard patterns cast in Co-Cr alloy (n=5).

Screw spreading: technical considerations and case report.

The spreading system is an alternative technique to the Summers osteotome. The crest expansion technique is a less invasive procedure in which the facial wall expands after the medullary bone is compressed against the cortical wall. It improves the density of the maxillary bone, which allows for greater initial stability of implants.

Comparative strain gauge analysis of external and internal hexagon, Morse taper, and influence of straight and offset implant configuration.

Purpose: The present study was designed to analyze strain distributions caused by varying the fixture-abutment design and fixture alignment.

Materials And Methods: Three implants of external, internal hexagon, and Morse taper were embedded in the center of each polyurethane block in straight placement and offset placement. Four strain gauges (SGs) were bonded on the surface of polyurethane block, which was designated SG1 placed mesially adjacent to implant A, SG2 and SG3 were placed mesially and distally adjacent to the implant B and SG4 was placed distally adjacent to the implant C.

Machined and plastic copings in three-element prostheses with different types of implant-abutment joints: a strain gauge comparative analysis.

Objective: Using strain gauge (SG) analysis, the aim of this in vitro study was quantify the strain development during the fixation of three-unit screw implant-supported fixed partial dentures, varying the types of implant-abutment joints and the type of prosthetic coping. The hypotheses were that the type of hexagonal connection would generate different microstrains and the type of copings would produce similar microstrains after prosthetic screws had been tightened onto microunit abutments.

Materials And Methods: Three dental implants with external (EH) and internal (IH) hexagonal configurations were inserted into two polyurethane blocks.

Rank Protein Immunolabeling during Bone-Implant Interface Healing Process.

The purpose of this paper was to evaluate the expression of RANK protein during bone-healing process around machined surface implants. Twenty male Wistar rats, 90 days old, after having had a 2 mm diameter and 6 mm long implant inserted in their right tibias, were evaluated at 7, 14, 21, and 42 days after healing. After obtaining the histological samples, slides were subjected to RANK immunostaining reaction.

Bone spreader technique: a preliminary 3-year study.

The purpose of this study was to observe the clinical outcome of bone spreading and standardized dilation of horizontally resorbed bone during immediate implant placement using a "screw-type" configuration of expansion and threadformers. Fifty-three patients were included in this study, and 41 edentulous areas in anterior and posterior maxillas were treated. Sixty-eight implants were placed using an insertion torque of at least 40 Ncm.