Glycolic acid and ultrasonic activation: Effects on smear layer removal, dentin penetration, dentin structure and bond strength of the root dentin filling material.

Background: Glycolic acid (GA) has been tested as enamel and dentin etchant, and final irrigant for smear layer removal. This study evaluated the effects of GA and ultrasonic activation (US) on smear layer removal, dentin penetration, dentin structure and bond strength of the root dentin filling material.

Material And Methods: The root canals of 210 teeth were distributed into four test groups: smear layer removal (N=50), dentin penetration (N=50), dentin structure (N=10) and bond strength (N=100).

Effect of anaerobic or/and microaerophilic atmosphere on microcosm biofilm formation and tooth demineralization.

Objective: Microcosm biofilms can reproduce the complexity of a dental biofilm. However, different forms of cultivation have been used. The impact of the culture atmosphere on the development of microcosm biofilms and their potential to cause tooth demineralization has not yet been deeply studied.

Effectiveness of ultrasonic activation over glycolic acid on microhardness, cohesive strength, flexural strength, and fracture resistance of the root dentin.

Objectives: The aim of this study was to evaluate the effectiveness of ultrasonic activation (US) over glycolic acid on microhardness, cohesive strength, flexural strength, and fracture resistance of root dentin, comparing with conventional final irrigation protocols.

Methods: Samples were obtained from 140 extracted bovine teeth and distributed into four test groups: microhardness (50 teeth), cohesive strength (15 teeth), flexural strength (15 teeth), and fracture resistance (60 teeth). In all four tests, specimens were subdivided into five groups, according to final irrigation protocols: G1: distilled water (DW); G2: 17% ethylenediaminetetraacetic acid (EDTA); G3: 17% glycolic acid (GA); G4: 17% EDTA + US; and G5: 17% GA + US.

Influence of the apical limit of instrumentation and photodynamic therapy on the postoperative pain of lower molars with asymptomatic apical periodontitis.

Introduction: The aim of present study was to evaluate the influence of apical limit of instrumentation and PDT on the postoperative pain of lower molars with asymptomatic apical periodontitis.

Methods: Forty patients were included in the present study and were divided into 4 groups (n=10), according to apical limit of instrumentation and use of PDT: instrumentation at 0.0 measurement; instrumentation at 0.

Influence of a glycolic acid-based final irrigant for photosensitizer removal of photodynamic therapy on the microhardness and colour change of the dentin structure.

Introduction: This study aimed to evaluate the influence of glycolic acid-based final irrigant for photosensitizer removal of photodynamic therapy on the microhardness and colour change of the dentin structure.

Methods: Eighty extracted single-rooted human incisors were used. Sample preparation and root split resulted in 160 samples, 80 samples being used for microhardness and 80 samples for colour change evaluation.

Association of calcium hypochlorite, reciprocating instrumentation and photodynamic therapy: Antimicrobial analysis and effects on root dentin structure.

Introduction: This study aimed to evaluate the antimicrobial action of calcium hypochlorite(Ca[OCl]) and sodium hypochlorite (NaOCl) with reciprocating instrumentation and photodynamic therapy(PDT), and its influence on root dentin structure.

Methods: One hundred and ten human teeth were used to antimicrobial evaluation, inoculated with Enterococcus faecalis and divided into 11 groups (n = 10): G1 - distilled water(control); G2-1 % NaOCl; G3-5.25 % NaOCl; G4-1 % Ca(OCl); G5-5.

Influence of final irrigation protocols and type of resin cement on bond strength of glass fiber posts in root dentin previously treated with photodynamic therapy.

Introduction: This study aimed to evaluate the influence of final irrigation protocols and type of resin cement on the bond strength of glass fiber posts (GFPs) in root dentin previously treated with photodynamic therapy (PDT).

Methods: One hundred root canals were prepared up to #4 Gates Glidden drill to receive the GFPs. All samples were subjected to PDT, and randomly divided into five groups (n = 20) according to final irrigation protocol: distilled water + ultrasonic activation [US]; 17% EDTA; QMix; 17% EDTA + US; and QMix + US.

Influence of final irrigation protocols and endodontic sealer on bond strength of root filling material with root dentin previously treated with photodynamic therapy.

Introduction: The aim of this study was to evaluate the influence of final irrigation protocols and endodontic sealer on bond strength of root filling material on root dentin previously treated with photodynamic therapy (PDT).

Methods: One hundred root canals were prepared up to #F3 file of Pro-Taper system to receive the root filling material. All samples were submitted to PDT and randomly divided into five groups (n = 20) according to final irrigation protocols: Group 1-distilled water + ultrasonic activation (US); Group 2-17% EDTA; Group 3-QMix; Group 4-17% EDTA + US; Group 5-QMix + US.