Apical periodontitis healing and postoperative pain following endodontic treatment with a reciprocating single-file, single-cone approach: A randomized controlled pragmatic clinical trial.

This trial assessed post-operative pain and healing of apical periodontitis following endodontic therapy with a reciprocating system compared to a crown-down technique with hand files and lateral compaction filling. One-hundred and twenty nonvital anterior teeth with apical periodontitis were randomly treated using either a reciprocating single file followed by matching-taper single-cone filling or a hand file and lateral compaction filling. Postoperative pain was assessed during the 7 days after the treatment, using a visual analogue scale and a verbal rating scale. Apical healing was assessed using the periapical index score after a 12-month follow-up. The hypothesis tested was that both protocols were equivalent and present similar effectiveness in healing periapical lesions. Data were analyzed through two one-sided tests, t-tests, as well as Mann-Whitney and Chi-squared tests (α = 0.05). Logistic regression was used to investigate the association of clinical and demographic factors with the success of treatment. Regardless of the assessment time, no difference in incidence (38%-43% at first 24h), intensity of postoperative pain, and incidence of flare-up (≈ 3%) was observed between the two endodontic protocols. Both protocols resulted in a similar healing rate of apical periodontitis. After 12 months, the success rate ranged from 73% to 78% and the difference between the treatments fell within the pre-established equivalence margin (-0.1; -0.41 to 0.2). Endodontic treatment combining a reciprocating single file with matching-taper single cone showed similar clinical effectiveness to the treatment using hand-file instrumentation and the lateral compaction filling.

Correction: Apical periodontitis healing and postoperative pain following endodontic treatment with a reciprocating single-file, single-cone approach: A randomized controlled pragmatic clinical trial.

[This corrects the article DOI: 10.1371/journal.pone.0227347.].

Kinetics of conversion of two dual-cured adhesive systems.

The aim of this study was to evaluate the kinetics of conversion of Scotchbond Multi-purpose Plus (3M ESPE, St Paul, MN) and Prime&Bond NT (Dentsply De Trey, Konstanz, Germany) used in light-cured, self-cured, or dual-cured versions. The adhesive systems were used in the light-cured version (without the use of chemical initiator) or mixed with its respective chemical initiator either with light activation (dual-cured) or not (self-cured). The degree of conversion (DC) was monitored as a function of time during 5 minutes with a Fourier transform infrared spectrometer equipped with an attenuated total reflectance device. Light-cured and dual-cured modes of Scotchbond Multi-purpose Plus presented the highest DC at 5 minutes. The addition of the self-cure activator (dual-cured mode) to Prime&Bond NT reduced the DC. For the self-cured versions, only the Scotchbond Multi-purpose Plus presented any polymerization reaction at 5 minutes. For the two bonding systems tested, it appears that light curing of the adhesive is important in order to reach a high DC in the first moments after the bonding procedure.

Diametral tensile strength of two brazilian resin-modified glass ionomers cements: influence of the powder/liquid ratio

The aim of this study was to evaluate the influence of powder/liquid ratio in the diametral tensile strength of two resin-modified glass ionomers cements (RMGIC). Two Brazilian brands of RMGIC: Resiglass R (RG: Biodinâmica) and Vitro Fil LC (VF: DFL) were used. Each product was mixed in two different powder/liquid ratios, (1:1) 1 scoop of powder to one drop of liquid or (1:2) 1 scoop of powder to 2 drops of liquid. The control was considered the powder/liquid ratio recommended by each manufacturer (RG 1:1 and VF 1:2 P/L). Four groups (n=5) with sample dimensions of 2.5 and 5.0 mm (thickness and diameter respectively) were tested. Diametral Tensile Test was performed in a mechanical testing machine (EMIC DL 500). Data obtained were submitted to One-way ANOVA and Tukey's multiple comparisons test (α=5%). For both national RMGICs, the experimental variations in the powder/liquid ratio led to an increase in diametral tensile strength when compared to the ratios advocated by the manufacturers. Group VL manipulated with experimental ratio1:1 showed statistically the highest (25.54±2.38 MPa) DTS mean among the tested groups whereas Resinglass R manipulated with 1:1 ratio, as advocated by manufacturer, showed statistically the lowest DTS mean (9.27±1.37 MPa). A review and further adjustments in the ratios recommended by the manufacturers of both resin-modified glass ionomers cements investigated is necessary.

Clareamento dental caseiro por meio de fitas adesivas: relato de caso / Home bleaching using whitening strips: a case report

O clareamento caseiro, com peróxido de carbamida a 10%, aplicado por meio de moldeiras personalizadas, ainda é o protocolo de tratamento mais utilizado, quando se quer branquear os dentes. No entanto, está disponível técnica mais recente, que consiste na utilização de fitas adesivas pré-contornadas, impregnadas com agente clareador, que contêm diferentes concentrações de peróxido de hidrogênio. Aplicadas uma ou duas vezes ao dia, as fitas são facilmente adaptadas aos dentes anteriores. O objetivo deste artigo é apresentar relato de clareamento dental caseiro com utilização de fitas adesivas impregnadas com peróxido de hidrogênio a 6%, abordando suas principais características, indicações e limitações.

Vital bleaching using 10% Carbamide Peroxide and custom-made trays is still the most used technique for dental bleaching. However, there is a novel technique for bleaching vital teeth using whitening strips containing different concentrations of hydrogen peroxide. The strips are easily adapted in a QD or BID regimen over the anterior teeth. The aim of this paper is to present a clinical case where 6% hydrogen peroxide strips were used, and to discuss the main characteristics, indications and limitations.