A Finite Element Stress Analysis of a Concical Triangular Connection in Implants: A New Proposal.

Conical implant-abutment connections are popular for their stability; however, in other conditions, such as excessive force, implants and abutments can absorb all the stress. Some connections with three points of support can resist more than conical connections. In recent years, different studies has shown that the design of a connection affects its stability.

Effect of Conditioning Protocols and Ultrasonic Application of an Infiltrant Resin in White Spot Lesions.

The aim of this study was to evaluate different conditioning protocols and sonic/ultrasonic application of an infiltrant resin (IR) in artificial white spot lesions (AWSL). the V/L surfaces of 48 molars were induced to an AWSL and divided in 6 groups, according to the conditioning protocols and application technique: 15% hydrochloric acid (HA) + manual application of the IR; HA + 37% phosphoric acid (PA) + manual application of the IR; HA + ultrasonic application (U) of the IR; HA + sonic application (S) of the IR; PA+HA+S; and PA+HA+U. For the Penetration Depth (PD), the crowns were etched with HA for 120s.

Effect of Different Adhesive Strategies on Bond Quality of Fiber Posts Cemented in Endodontically Treated Teeth.

Introduction: The purpose of this study was to assess the effects of anatomic root levels, different adhesive strategies and cementation system on bond strength (BS), nano leakage (NL) and degree of conversion (DC) after fiber posts cementation.

Methods And Materials: Sixty-six roots of human premolars were endodontically prepared and divided according to the combination of adhesive application technique (manual passive, manual active and active vibratory) and the cementation system (Adper Single Bond 2/RelyX ARC [SBAR] and Single Bond Universal/RelyX Ultimate [SBUL]). Specimens were transversally sectioned into six 1-mm-thick serial slices, which were subjected to BS testing (=7), to NL analysis using scanning electron microscopy (SEM) after slice immersion in silver nitrate (=2), and micro-Raman spectroscopy for DC (=2).

Effect of the Bis-Dimethylamino Benzydrol Coinitiator on the Mechanical and Biological Properties of a Composite.

To examine the effect of the alternative coinitiator 4,4'bis dimethylamino benzydrol (BZN) in degree of conversion (DC), mechanical and biological properties of experimental composites. The coinitiator BZN was used in three concentrations (0.2, 0.

Active and Passive Application of the Phosphoric Acid on the Bond Strength of Lithium Disilicate.

The objective of this study was to evaluate the effect of passive or active phosphoric acid (PA) application after hydrofluoric acid (HA) treatment on the microshear bond strength of lithium disilicate. Thirty ceramic discs were made with IPS Emax 2 (10 mm thick and 10 mm diameter). The specimens were divided into 3 groups, A: 9.

Alternative coinitiators applicable to photocurable resin composites.

This review aimed to examine the evolution of the composite resins`s photoinitiator system, with emphasis on those developed in recent years. This review covered literature from 1990 to 2013 and only papers with the key words of interest were included: "coinitiators", "amines", "composite resins", "photopolymerization". The search used full-text papers from PubMed and Science Direct databasis.

Influence of two different methods of delivering fluoride on bond strength and degree of conversion of an adhesive after bleaching.

Purpose: To evaluate the influence of fluoride delivery and restoration time point on the microshear bond strength (mSBS) and degree of conversion (DC) values of an adhesive applied on bleached enamel.

Materials And Methods: Fifty-four enamel specimens were submitted to bleaching and divided into 3 groups of n = 18: group HP: 35% hydrogen peroxide (HP); group HPF: HP + 1.23% sodium fluoride application (F); group PF: 38% HP with F.

Ultrastructural evaluation of enamel after dental bleaching associated with fluoride.

This study evaluated the effects on human enamel after two bleaching procedures: with a fluoridated bleaching agent and with topical fluoride application postbleaching. It used 43 enamel blocks (3 mm(2) ) that were ground flat (600-2,000 grit) and polished with polishing paste (one and one-fourth). Specimens were randomly divided into three groups according to the bleaching procedure: (1) control group, (2) hydrogen peroxide 35% (HPF) and topical application of fluoride 1.

Case-Control study of Firefighters with documented positive tuberculin skin test results using Quantiferon-TB testing in comparison with Firefighters with negative tuberculin skin test results.

Background: Phoenix Firefighters have had abnormally high rates of tuberculin skin test (TBST) results on medical surveillance. The objectives of this study were to evaluate our firefighters using QuantiFERON-TB (QFT), comparing the results to their TBST results.

Methods: Using QFT results obtained during the study, we compared previously positive TBST responders (Cases) to negative responders (Controls).