Influence of carbonated acid beverage on fracture resistance and marginal gap formation in different restorative approaches to non-carious cervical lesions.

Objective: This study is to evaluate fracture resistance, failure mode, and gap formation at the restorative interface of unrestored or restored non-carious cervical lesions (NCCLs) submitted to a short-term erosive environment.

Materials And Methods: Artificial NCCLs were produced in vitro in bovine incisors, and were randomly divided into four restorative resins groups (n = 22): nanohybrid-NR; bulk-fill-BR; flow with a nanohybrid layer-FNR; bulk-fill with a nanohybrid layer-BNR; and a group unrestored-UR (n = 16). Half of the specimens were submitted to an erosive challenge (per 5 min, 3 × a day for 7 days, before and after restoration), and the other half, was immersed in artificial saliva.

Relationship between normative and self-perceived criteria for orthodontic treatment need and satisfaction with esthetics and mastication in adolescents.

Introduction: Orthodontic treatments are performed to improve esthetics and masticatory functions. In general, clinical criteria are used to recommend such treatments without considering the opinion of the patient. This study aimed to evaluate the relationship between technically defined orthodontic need (normative criteria) and the need for treatment perceived by adolescent patients.

Microleakage at Different Implant-Abutment Connections Under Unloaded and Loaded Conditions.

Purpose: This study evaluated the microleakage at different implant-abutment (I-A) connections under unloaded and loaded conditions.

Materials And Methods: Forty implants, specially designed with an opening at the apex, were grouped according to the I-A and screw device: external hexagon implants with titanium (EH) or EH diamond-like carbon screws fixing the abutment; internal hexagon implants with titanium screws (IH); and Morse taper implants with solid (MT) or MT passing screws (MTps) abutments. The implants were fixed in a 2-compartment device, and toluidine blue solution (1.

Bacterial Adhesion and Surface Roughness for Different Clinical Techniques for Acrylic Polymethyl Methacrylate.

This study sought to assess the effect of different surface finishing and polishing protocols on the surface roughness and bacterial adhesion (S. sanguinis) to polymethyl methacrylates (PMMA). Fifty specimens were divided into 5 groups (n = 10) according to their fabrication method and surface finishing protocol: LP (3 : 1 ratio and laboratory polishing), NF (Nealon technique and finishing), NP (Nealon technique and manual polishing), MF (3 : 1 ratio and manual finishing), and MP (3 : 1 ratio and manual polishing).

Fracture Resistance of Internal Conical and External Hexagon: Regular and Narrow Implant-Abutment Assemblies.

Purpose: The aim of this study was to compare the maximum load on the elastic limit of internal conical (IC) implants with regular external hexagon (REH) and narrow external hexagon (NEH) implants.

Materials And Methods: Thirty cylindrical implants were divided in 3 groups (n = 10): REH (3.75 mm); NEH (3.

Photoelastic stress analysis of mandibular fixed prostheses supported by 3 dental implants.

Purpose: To observe the photoelastic stress patterns generated around implants in relation to variations in the diameter and total number of implants supporting fixed complete-arch mandibular frameworks.

Materials And Methods: Three different implant configurations were analyzed (n = 3): 5 standard implants with diameters of 3.75 mm (C), 3 standard implants with diameters of 3.

Stress analysis of different configurations of 3 implants to support a fixed prosthesis in an edentulous jaw.

This study's aim was to evaluate the stress distribution in a mandibular implant-supported prosthesis and peri-implant bone considering implant quantity, diameter and position using linear 3-D finite element analysis. Models of an anterior jaw comprised 4 groups according to implant quantity, diameter, and position: control group C, 5 regular implants; R, 3 regular implants; W, 3 wide implants; and DTR, 3 regular implants with the distal ones tilted 30° distally. The cantilever was loaded with an axial load of 50 N.

Influence of crown-to-implant ratio on stress around single short-wide implants: a photoelastic stress analysis.

Purpose: The aim of this study was to evaluate the photoelastic fringe patterns around two short-wide implants supporting single crowns with different crown-to-implant (C/I) ratios.

Materials And Methods: External hexagon (EH) cylindrical implants (5 × 7 mm) or Morse Taper (MT) conical implants (5 × 6 mm) were embedded individually into photoelastic resin blocks. Each implant received a single metal-ceramic crown, with a C/I ratio of 1:1 or 2:1 (n = 10).

Photoelastic stress analysis of different wide implant/abutment interfaces under oblique loading.

Purpose: There is a variety of implant/abutment (I/A) junctions for the connection of implant-supported prostheses. The aim of this work was to compare the shear stress distribution in three types of I/A interfaces after application of oblique loading on the abutments, simulating loading on an anterior tooth.

Materials And Methods: Similar wide unthreaded and cylindric implants (13.

Micro-leakage at the implant-abutment interface with different tightening torques in vitro.

Objectives: This study evaluated the microleakage at the implant/abutment interface of external hexagon (eH) implants and abutments with different amounts of bacteria and tightening torques.

Material And Methods: A bacterial suspension was prepared to inoculate the implants. The first phase of this study used nine EH implants and abutments that were divided into three groups with different amounts of bacterial suspension (n=3): V0.

Influence of methodologic aspects on the results of implant-abutment interface microleakage tests: a critical review of in vitro studies.

Purpose: This study sought to evaluate the influence of methodologic aspects on variations in the findings of in vitro microleakage studies of the implant-abutment interface.

Materials And Methods: The MEDLINE, EMBASE, and Cochrane Library databases were consulted for in vitro studies published between 1990 and August 2011. Date from the studies that met the inclusion and exclusion criteria were arranged in tables and subjected to descriptive analysis.

Comparison of implant-abutment interface misfits after casting and soldering procedures.

The aim of this study was to compare vertical and horizontal adjustments of castable abutments after conducting casting and soldering procedures. Twelve external hexagonal implants (3.75 × 10 mm) and their UCLA abutments were divided according their manufacturer and abutment type: PUN (plastic UCLA, Neodent), PUC (plastic UCLA, Conexão), PU3i (plastic UCLA, Biomet 3i), and PUTN (plastic UCLA with Tilite milled base, Neodent).

Evaluation of screw loosening on new abutment screws and after successive tightening.

This study evaluated the loss of the torque applied after use of new screws and after successive tightening. Four infrastructures (IE), using UCLA castable abutment type, were cast in cobalt-chromium alloy and new abutment screws (G1) were used in a first moment. Subsequently, the same abutment screws were used a second time (G2) and more than two times (G3).

Implant-supported prosthesis misalignment related to the dental arch: a 14-year clinical follow-up.

The purpose of this study was to warn the dental community about a possible problem in function with partial implant-supported prostheses used for long periods. The misalignment between natural teeth and the implant-supported prosthesis on teeth 11 and 12, observed in a 14-year clinical follow-up, illustrates the fact. The metal-ceramic crowns were placed in 1995 after a rigorous occlusal adjustment.