Does etching time affect the in vitro performance of a sealant material?

This in vitro study evaluated the shear bond strength (SBS), failure mode and microleakage of fissure sealing materials in relation to different etching times on aprismatic and prismatic enamel. Ninety-six healthy human third molars were randomly allocated to the following groups: 1) prismatic or aprismatic enamel; 2) etching: 15, 30, 45, 60 s. After 5,000-fold thermocycling SBS, failure mode and microleakage were measured.

Meta-analysis of the longevity of commonly used pit and fissure sealant materials.

Objective: This systematic literature review and meta-analysis compared the clinical retention of primed or adhesively bonded sealants to that of conventional sealant materials.

Methods: A search of the MEDLINE, EMBASE and CENTRAL databases identified 3707 abstracts published prior to 12/31/2017, of which 335 clinical publications were analysed in detail. A total of 67 studies included information about sealant retention after 24, 36, or 60 months of follow-up.

What is an Appropriate Etching Time For Sealant Application on Permanent Molars? Results from a Meta-Analysis.

Purpose: This meta-analysis investigated the influence of different acid etching times on the retention rate of pit-and-fissure sealants based on clinical trials with a minimum duration of two years.

Materials And Methods: A literature search was carried out in electronic databases along with hand searching to identify clinical trials that evaluated pit-and-fissure sealants in permanent molars. From 1280 identified abstracts, 195 studies were selected for full-text analysis, and 28 studies with 36 test groups were included in this meta-analysis.

[Bracing in Adolescent Idiopathic Scoliosis].

Scoliosis is a common medical problem, with an incidence of between 0.47% and 5.2% in the general population globally.

Which Factors Influence the Shear Bond Strength of Sealant Materials?

Purpose: This study investigated the influence of several methodological details on the shear bond strength (SBS) testing of pit and fissure sealants. The following variables were considered: type of enamel surfaces, prismatic vs aprismatic enamel, etching time, and aging and shearing procedures.

Materials And Methods: The surfaces of 180 healthy human third molars were divided into 4 different sections (mesial, distal, buccal, and oral).

Synthesis of 3-alkoxymethylcoumarin from 3-cyanochromene via a novel intermediate 2-phenylimino-3-alkoxymethylchromene.

In this paper a concise, efficient, and environmentally benign method for the synthesis of 3-alkoxymethylcoumarin is described. From the reaction of 3-cyanochromene with an alkoxide and arylamine in THF, (Z)-2-phenylimino-3-alkoxymethylchromene was obtained as a novel intermediate via an isomerization of the double bond, a 1,2-addition of alkoxide, a Michael-type addition of aniline, an another isomerization of double bond and an elimination of ammonia. Subsequently, the intermediate was converted into the desired coumarin by treatment with 15% HCl in THF in good yield.